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1

Zinc phosphide-zinc oxide heterojunction solar cells  

Microsoft Academic Search

Zinc phosphide-zinc oxide heterojunction solar cells have been prepared by sputter-depositing ZnO onto a Zn3P2 substrate. An active-area conversion efficiency of 2% has been obtained. In the absence of shunts and by reducing the series resistance of the device, an efficiency of 5% is achievable. The experimental results are discussed in terms of an interface recombination model. It is indicated

P. S. Nayar; A. Catalano

1981-01-01

2

Photovoltaic cells employing zinc phosphide  

DOEpatents

A photovoltaic cell having a zinc phosphide absorber. The zinc phosphide can be a single or multiple crystal slice or a thin polycrystalline film. The cell can be a Schottky barrier, heterojunction or homojunction device. Methods for synthesizing and crystallizing zinc phosphide are disclosed as well as a method for forming thin films.

Barnett, Allen M. (Newark, DE); Catalano, Anthony W. (Wilmington, DE); Dalal, Vikram L. (Newark, DE); Masi, James V. (Wilbraham, MA); Meakin, John D. (Newark, DE); Hall, Robert B. (Newark, DE)

1984-01-01

3

PLD growth of thin film Zinc Phosphide  

NASA Astrophysics Data System (ADS)

The development of efficient, low cost solar cells to meet society's growing energy needs has triggered tremendous interest in developing photovoltaics formed from earth abundant materials. Zinc phosphide (Zn3P2) is a promising earth abundant absorber layer for photovoltaic energy conversion with a nearly ideal band gap (1.5eV) and a large absorption coefficient of 10^4/cm. In this work we examine the growth parameters, electrical and optical properties of thin film zinc phosphide produced using pulsed laser deposition (PLD) from a zinc phosphide target at laser fluencies ranging from 1-3 J/cm2. For the laser fluences explored, highly resistive amorphous zinc phosphide thin films were produced with a band gap of approximately 1.7 eV. The thin films could be transformed from amorphous to polycrystalline zinc phosphide by annealing at 400C for 15mins in a N2 atmosphere. High resolution X-ray photoelectron spectroscopy (XPS) is used to examine the binding energies of Zn 2p3/2 and Phosphorous 2p3/2 signals and are in the range of 1021.6 eV and 127.5 eV. Energy Dispersive X-ray Spectroscopy (EDAX) revealed that the Zn3P2 thin films are nearly stoichiometric in composition. Hall mobility in these materials and Zn3P2/ZnS hetrojunction solar cell performance will be discussed.

Vaddi, Rajesh; Vasekar, Parag; Westgate, Charles; White, Bruce

2013-03-01

4

Indium Phosphide Solar Cells: a Materials Growth Study.  

NASA Astrophysics Data System (ADS)

The objective of this research was the fabrication and optimization of InP material to improve solar cells for space applications. The performance of solar cells is determined to a large extent by the quality of the material used to fabricate these structures. For the n ^+pp^+ cells used here, the important material properties are: lifetime in the p-type base, and dopant incorporation and heavy doping effects in the n^+ emitter. In this thesis, study of these properties and growth processes is reported. To maximize hole lifetime in undoped InP, it was studied as a function of growth conditions. The lifetime increases proportional to the growth rate, and is approximately 50 ns for a growth rate of 4.5 mum/hr. A series of experiments showed that the non-radiatively controlled lifetime is limited by impurities coming from the phosphine. This work suggests that, to get higher lifetime, an improved source of phosphine is required. The complete solar cell utilizes doped regions and its fabrication requires a series of thermal processes. The lifetime in this structure could be reduced either due to the dopant or the thermal processing. The electron lifetime was measured for solar cells with a Cd doped base, and was approximately 5 ns. The results indicate that Cd is an excellent acceptor for solar cells as it does not affect lifetime, and that the processing steps have little effect on the material. For the n^+ emitter, a study of the incorporation behaviour of S for heavy doping levels is reported. Regimes of linear, superlinear, and retrograde incorporations are observed. An incorporation model is presented to explain this behaviour. Heavy doping of semiconductor distorts the band structure and reduces the band gap. Room temperature photoluminescence is used to quantify these heavy doping effects for S doped InP.

Tyagi, Sunit Dharamveer

5

40 CFR 180.284 - Zinc phosphide; tolerances for residues.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Zinc phosphide; tolerances for residues...FOOD Specific Tolerances § 180.284 Zinc phosphide; tolerances for residues...resulting from the use of the rodenticide zinc phosphide in or on the raw...

2013-07-01

6

A review of indium phosphide space solar cell fabrication technology  

Microsoft Academic Search

A review of the status of InP cell efficiency and of approaches to the reduction of cell cost is presented. The use of heteroepitaxial techniques such as InP-on-GaAs and InP-on-Si is discussed along with the use of chemical and mechanical techniques for removal and recovery of the substrate. The efficiency ultimately obtainable with designs made possible by such an approach

M. B. Spitzer; B. Dingle; J. Dingle; R. Morrison

1990-01-01

7

Indium phosphide/cadmium sulfide thin-film solar cells  

SciTech Connect

Thin-film InP/CdS structures were prepared by depositing, in sequence, ITO on a low-cost glass substrate, CdS on the ITO by thermal evaporation, and InP on the CdS by planar reactive deposition (PRD). Films of CdS, 15 ..mu..m thick, were recrystallized in flowing H/sub 2//H/sub 2/S at 500/sup 0/C. Lateral dimensions of typical grains were 50..mu..m with values up to 200 ..mu..m. The sheet resistance of the recrystallized CdS (RXCdS) was lowered from greater than 10/sup 5/ ..cap omega../O = cm/sup 2/ to values as low as 16 ..cap omega../O = cm/sup 2/ by annealing in either H/sub 2/ Cd atmospheres. Epitaxy of InP was undertaken on (100) InP at a substrate temperature of 320/sup 0/C. Room-temperature electron mobilities of about 2000 cm/sup 2//V-sec were found. Mobilities and hole concentrations of 60 cm/sup 2//V-sec and 10/sup 17/ cm-/sup 3/, respectively, were achieved with Be-doped films. P-type films with hole concentrations as high as a few times 10/sup 18/cm-/sup 3/ were achieved with increased doping. Be-doped InP was deposited onto the RXCdS/ITO/GLASS substrate to form a thin-film cell. However, p-type InP could not be prepared with CdS as a substrat4e, presumably due to interdiffusion or vapor transport of sulfur. Consequently, blocking action and a photovoltage could only be achieved using a gold Schottky barrier on the InP/RXCdS/ITO/GLASS structure. Plans for the next quarter include determining whether n-type doping from the CdS occurs by either interdiffusion or vapor transport, characterizing InP epitaxy on the RXCdS, and preparing additional thin-film structures.

Zanio, K.

1980-02-01

8

Amorphous silicon/polycrystalline thin film solar cells.  

National Technical Information Service (NTIS)

An improved photovoltaic solar cell is described including a p-type amorphous silicon layer, intrinsic amorphous silicon, and an n-type polycrystalline semiconductor such as cadmium sulfide, cadmium zinc sulfide, zinc selenide, gallium phosphide, and gall...

H. S. Ullal

1991-01-01

9

Nickel phosphide-embedded graphene as counter electrode for dye-sensitized solar cells.  

PubMed

Nickel phosphide-embedded graphene, prepared by the hydrothermal reaction of red phosphorus, nickel chloride, and graphene oxide in a mixture of ethylene glycol-water, is investigated as the counter electrode of DSSCs. It is demonstrated that the DSSC with the nickel phosphide-embedded graphene as the new counter electrode presents an excellent performance competing with that of the Pt electrode. PMID:22160103

Dou, Y Y; Li, G R; Song, J; Gao, X P

2011-12-12

10

Responses of Siberian ferrets to secondary zinc phosphide poisoning  

USGS Publications Warehouse

The hazard of operational-type applications of zinc phosphide (Zn3P2) on a species closely related to the black-footed ferret (Mustela nigripes), was evaluated by feeding 16 Siberian ferrets (M. eversmanni) rats that had been killed by consumption of 2% zinc phosphide treated bait or by an oral dose of 40, 80, or 160 mg of Zn3P2. All ferrets accepted rats and a single emesis by each of 3 ferrets was the only evidence of acute intoxication. All ferrets learned to avoid eating gastrointestinal tracts of the rats. Subacute zinc phosphide toxicity in the ferrets was indicated by significant decreases (18-48%) in hemoglobin, increases of 35-91 % in serum iron, and elevated levels of serum globulin, cholesterol, and triglycerides. Hemoglobin/iron, urea nitrogen/creatinine, and albumin/globulin ratios also were altered by the treatments. This study demonstrated that Siberian ferrets, or other species with a sensitive emetic reflex, are afforded a degree of protection from acute zinc phosphide poisoning due to its emetic action. The importance of toxicity associated with possible respiratory, liver, and kidney damage indicated by altered blood chemistries is not known.

Hill, E.F.; Carpenter, J.W.

1982-01-01

11

Indium phosphide solar cell research in the United States: Comparison with non-photovoltaic sources  

Microsoft Academic Search

Highlights of the InP solar cell research program are presented. Homojunction cells with efficiencies approaching 19 percent are demonstrated, while 17 percent is achieved for ITO\\/InP cells. The superior radiation resistance of the two latter cell configurations over both Si and GaAs cells has been shown. InP cells aboard the LIPS3 satellite show no degradation after more than a year

I. Weinberg; C. K. Swartz; R. E. Hart Jr.

1989-01-01

12

Assessing potential risk to alligators, Alligator mississippiensis, from nutria control with zinc phosphide rodenticide baits.  

PubMed

Nutria, Myocastor coypus, populations must be reduced when they cause substantial wetland damage. Control can include the rodenticide zinc phosphide, but the potential impacts to American alligators, Alligator mississippiensis, must be assessed. The mean amount of zinc phosphide per nutria found in nutria carcasses was 50 mg. Risk assessment determined that a conservative estimate for maximum exposure would be 173 mg zinc phosphide for a 28 kg alligator, or 6.2 mg/kg. Probit analysis found an LD(50) for alligators of 28 mg/kg. Our studies suggest that the use of zinc phosphide to manage nutria populations would pose only a small risk to alligators. PMID:20431861

Witmer, Gary W; Eisemann, John D; Primus, Thomas M; O'Hare, Jeanette R; Perry, Kelly R; Elsey, Ruth M; Trosclair, Phillip L

2010-04-30

13

Junction Characteristics of Indium Tin Oxide/Indium Phosphide Solar Cells.  

National Technical Information Service (NTIS)

Efficient indium tin oxide (ITO)/p-InP solar cells have been fabricated. Typical uncorrected efficiencies range from 9 to 12% at Am1 intensities. It is shown that deposition of ITO causes a semi-insulating layer at the InP surface as determined by C-V mea...

P. Sheldon R. K. Ahrenkiel R. E. Hayes P. E. Russell R. N. Nottenburg

1982-01-01

14

Developing a full cycled silicon cathode-zinc electrolyte based solar cell using copper recovery electrodes  

Microsoft Academic Search

This work presents an effective and low cost method to develop a fully cycled photo electrochemical solar cell by incorporating a copper auxiliary electrode. The continued function of the previously demonstrated photo-electrochemical solar cells consisting of silicon and zinc electrodes, relies on the existence of a zinc source. Therefore, consumption of the zinc anode and transfer of metallic zinc to

Babak Tousifar; Willy Douglas; Siavash Pourkamali

2011-01-01

15

Assessing Potential Risk to Alligators, Alligator mississippiensis , from Nutria Control with Zinc Phosphide Rodenticide Baits  

Microsoft Academic Search

Nutria, Myocastor coypus, populations must be reduced when they cause substantial wetland damage. Control can include the rodenticide zinc phosphide,\\u000a but the potential impacts to American alligators, Alligator mississippiensis, must be assessed. The mean amount of zinc phosphide per nutria found in nutria carcasses was 50 mg. Risk assessment determined\\u000a that a conservative estimate for maximum exposure would be 173 mg zinc

Gary W. Witmer; John D. Eisemann; Thomas M. Primus; Jeanette R. O’Hare; Kelly R. Perry; Ruth M. Elsey; Phillip L. Trosclair

2010-01-01

16

Indium phosphide/cadmium sulfide thin-film solar cells. Final report, June 1980-June 1981  

SciTech Connect

Thin-films of InP were grown on recrystallized CdS (RXCdS) and InP by planar reactive deposition for the purpose of determining the factors which limit the development of InP/RXCdS thin-film solar cells. InP films were grown on RXCdS at substrate temperatures of 380/sup 0/C, 330/sup 0/C, and 280/sup 0/C; epitaxy of InP was achieved only at 280/sup 0/C. An InCdS transition layer is present at temperatures above 300/sup 0/C and may inhibit InP epitaxy. Be-doped films could not be made p-type on either RXCdS or semi-insulating (100) InP at a substrate temperature of 280/sup 0/C. P-type behavior was only occasionally obtained at 330/sup 0/C. At approximately 330/sup 0/C, MBE data shows a transition from a reconstructed surface at a higher temperature to an atomically smooth surface at a lower temperature. A change in surface kinetics at this temperature may alter the doping mechanism. Therefore, the electron concentration was examined as a function of the ratio of the phosphorus to indium fluxes for unintentionally doped films prepared on (100) semi-insulating InP substrates at 330/sup 0/C to alter the surface kinetics. No dependence of conductivity on deviations from stoichiometry was found. The growth of InP in a halide environment at reduced pressure is recommended as an alternative approach to enhance the growth of p-type InP at a lower substrate temperature. Growth of InP with PCl/sub 3/ was initiated at atmospheric pressure. Alternative device structures are presented which avoid the p-type doping problem.

Zanio, K.

1981-10-01

17

Metal site disorder in zinc tin phosphide  

SciTech Connect

The optoelectronic properties of the II--IV--V/sub 2/ semiconductor ZnSnP/sub 2/ are studied as a function of the cooling rate of the crystal growth melt. The structure of the material, as studied by x-ray diffraction, is seen to change from chalcopyrite to sphalerite as the cooling rate is increased. Photoelectrochemical measurements show that the bandgap of the material decreases from 1.64 eV for the chalcopyrite to 1.25 eV as the structure approaches sphalerite. The /sup 119/Sn Moessbauer spectroscopy shows both an isomer shift and a broadening of the /sup 119/Sn resonance as a result of new tin environments produced by disordering of zinc and tin sites at the faster cooling rates. The /sup 31/P solid-state nuclear magnetic resonance spectroscopy clearly shows new resonances associated with the additional phosphorus environments produced by metal site disordering. A model based on zinc and tin site exchange with the introduction of compensating donor and acceptor states is proposed and discussed.

Ryan, M.A.; Peterson, M.W.; Williamson, D.L.; Frey, J.S.; Maciel, G.E.; Parkinson, B.A.

1987-07-01

18

Power recovery of radiation damaged MOCVD grown indium phosphide on silicon solar cells through argon-ion laser annealing. Master`s thesis  

SciTech Connect

This thesis reports the results of a laser annealing technique used to remove defect sites from radiation damaged indium phosphide on silicon MOCVD grown solar cells. This involves the illumination of damaged solar cells with a continuous wave laser to produce a large forward-biased current. The InP/Si cells were irradiated with 1 MeV electrons to a given fluence, and tested for degradation. Light from an argon laser was used to illuminate four cells with an irradiance of 2.5 W/sq cm, producing a current density 3 to 5 times larger than AMO conditions. Cells were annealed at 19 deg C with the laser and at 25 deg C under AMO conditions. Annealing under laser illumination of n/p-type cells resulted in recovery of 48%. P/n type cells lost 4 to 12% of the assumed degradaton. Annealing under AMO conditions resulted in power recovery of 70% in n/p type cells. P/n-type cells recovered approximately 16% of lost power. Results indicate that significant power recovery results from the annealing of defects within n/p type InP/Si solar cells.

Boyer, L.L.

1996-06-01

19

Radiation and temperature effects in gallium arsenide, indium phosphide, and silicon solar cells  

NASA Astrophysics Data System (ADS)

The effects of radiation on performance are determined for both n+p and p+n GaAs and InP cells and for silicon n+p cells. It is found that the radiation resistance of InP is greater than that of both GaAs and Si under 1-MeV electron irradiation. For silicon, the observed decreased radiation resistance with decreased resistivity is attributed to the presence of a radiation-induced boron-oxygen defect. Comparison of radiation damage in both p+n and n+p GaAs cells yields a decreased radiation resistance for the n+p cell attributable to increased series resistance, decreased shunt resistance, and relatively greater losses in the cell's p-region. For InP, the n+p configuration is found to have greater radiation resistance than the p+n cell. The increased loss in this latter cell is attributed to losses in the cell's emitter region. Temperature dependency results are interpreted using a theoretical relation for dVoc/dT, which predicts that increased Voc should result in decreased numerical values for dPm/dT. The predicted correlation is observed for GaAs but not for InP, a result which is attributed to variations in cell processing.

Weinberg, I.; Swartz, C. K.; Hart, R. E., Jr.; Statler, R. L.

20

Radiation and temperature effects in gallium arsenide, indium phosphide and silicon solar cells  

NASA Astrophysics Data System (ADS)

The effects of radiation on performance are determined for both n(+)p and p(+)n GaAs and InP cells and for silicon n(+)p cells. It is found that the radiation resistance of InP is greater than that of both GaAs and Si under 1 MeV electron irradiation. For silicon, the observed decreased radiation resistance with decreased resistivity is attributed to the presence of a radiation induced boron-oxygen defect. Comparison of radiation damage in both p(+)n and n(+)p GaAs cells yields a decreased radiation resistance for the n(+)p cell attributable to increased series resistance, decreased shunt resistance, and relatively greater losses in the cell's p-region. For InP, the n(+)p configuration is found to have greater radiation resistance than the p(+)n cell. The increased loss in this latter cell is attributed to losses in the cell's emitter region. Temperature dependency results are interpreted using a theoretical relation for dVoc/cT which predicts that increased Voc should results in decreased numerical values for dPm/dT. The predicted correlation is observed for GaAs but not for InP a result which is attributed to variations in cell processing.

Weinberg, I.; Swartz, C. K.; Hart, R. E., Jr.; Statler, R. L.

21

Amorphous silicon\\/polycrystalline thin film solar cells  

Microsoft Academic Search

An improved photovoltaic solar cell is described including a p-type amorphous silicon layer, intrinsic amorphous silicon, and an n-type polycrystalline semiconductor such as cadmium sulfide, cadmium zinc sulfide, zinc selenide, gallium phosphide, and gallium nitride. The polycrystalline semiconductor has an energy bandgap greater than that of the amorphous silicon. The solar cell can be provided as a single-junction device or

Ullal

1991-01-01

22

Investigation on Zinc Sulphide Nanoparticles in Dye Sensitized Solar Cell  

NASA Astrophysics Data System (ADS)

Nanoparticles of zinc sulphide in cubic sphalerite phase are synthesized by aqueous chemical method. UV-Vis absorption spectrum of nano ZnS is blue shifted from the bulk by 50 nm and methyl blue sensitized nano ZnS shows a strong visible absorption at 600 nm. PL spectrum of methyl blue sensitized ZnS shows two broad emission at 402 nm and 510 nm which are compared with earlier investigations and discussed. The solar conversion efficiency (?) of this dye sensitized solar cell (DSSC) was found to have enhanced due to charge transfer from dye molecules.

Ragam, M.; Sankar, N.; Ramachandran, K.

2011-07-01

23

Identification of phases in thin amorphous films of zinc phosphides  

SciTech Connect

Analysis of the experimental atomic radial distribution functions for thin amorphous films of zinc phosphides obtained by explosive laser sputtering has been performed within a fragmentary model. The experiment was carried out with an Emp-10a electron diffractometer in transmitted light at accelerating voltages of 50 and 75 kV. The films obtained by sputtering of {beta}-ZnP{sub 2} single crystals contained nanoparticles of this phase. The films based on Zn{sub 3}P{sub 2} turned out to be two-phase and consisted of dispersed Zn{sub 3}P{sub 2} and {beta}-ZnP{sub 2} nanoparticles. The composition of the film obtained on the basis of {alpha}-ZnP{sub 2} corresponded neither to any one of the known phases in the Zn-P system nor to any mixture of these phases. Crystallization of films in a divergent electron beam confirmed the results of the phase analysis performed using the model atomic radial distribution functions.

Aleinikova, K. B.; Zinchenko, E. N., E-mail: zinchenko@phys.vsu.ru; Lesovoi, M. V. [Voronezh State University (Russian Federation)

2007-03-15

24

Doped zinc oxide window layers for dye sensitized solar cells  

NASA Astrophysics Data System (ADS)

The present paper reports the fabrication of dye sensitized solar cell (DSSC), where boron doped ZnO (BZO) and aluminum-boron co-doped ZnO (AZB) thin films were used as front window electrodes. The highly crystalline zinc oxide (ZnO) nanoparticles (NPs) synthesized by the sol-gel route were used as host material for the dye. The efficiencies of the DSSCs formed using the BZO and AZB as window layers were obtained to be 1.56 and 1.84%, respectively. The enhanced efficiency in the case of an AZB window layer based DSSC is attributed to the increase in conductivity induced by co-doping of Al and B and an increase in the number of conducting pathways between the window layer and NPs provided by the nanorods. This facilitates a new approach in the window layer (doped ZnO) for DSSC application.

Kumar, Vinod; Singh, Neetu; Kumar, Vijay; Purohit, L. P.; Kapoor, Avinashi; Ntwaeaborwa, Odireleng M.; Swart, Hendrik C.

2013-10-01

25

Preparation and Study of the Properties of Indium Phosphide Thin Films Impregnated with Cadmium and Zinc.  

National Technical Information Service (NTIS)

Indium phosphide thin films were deposited by vacuum evaporation of indium and phosphorous, using the three-temperature method. The effects of the introduction of cadmium and zinc, group II impurities, on the properties of these films were studied. The in...

H. R. Moutinho

1984-01-01

26

CdS/CdTe Thin-Film Solar Cell with a Zinc Stannate Buffer Layer.  

National Technical Information Service (NTIS)

This paper describes an improved CdS/CdTe polycrystalline thin-film solar-cells device structure that integrates a zinc stannate (Zn2SnO4 or ZTO) buffer layer between the transparent conductive oxide (TCO) layer and the CdS window layer. Zinc stannate fil...

A. Mason H.R. Moutinho P. Sheldon R. Ribelin T.J. Coutts

1998-01-01

27

Effect of Ultraviolet Light on Hybrid Zinc Oxide Polymer Bulk Heterojunction Solar Cells  

Microsoft Academic Search

Compared to conjugated polymer poly[2-methoxy-5-(3',7'-dimethyloctyloxy)-1,4-phenylenevinylene] (MDMO-PPV) solar cells, bulk heterojunction solar cells composed of zinc oxide (ZnO) nanocrystals and MDMO-PPV have a better energy conversion efficiency. However, ultraviolet (UV) light deteriorates the performance of solar cells composed of ZnO and MDMO-PPV. We propose a model to explain the effect of UV illumination on these ZnO:MDMO-PPV solar cells. According to this

Jun-Peng Liu; Sheng-Chun Qu; Yong-Hai Chen; Ying Xu; Xiang-Bo Zeng; Ling-Yan Liang; Zhi-Jie Wang; Hui-Ying Zhou; Zhan-Guo Wang

2007-01-01

28

Organic solar cells on indium tin oxide and aluminum doped zinc oxide anodes  

Microsoft Academic Search

The authors compare organic solar cells using two different transparent conductive oxides as anode: indium tin oxide (ITO) and three kinds of aluminum doped zinc oxide (ZAO). These anodes with different work functions are used for small molecule photovoltaic devices based on an oligothiophene derivative as donor and fullerene C60 as acceptor molecule. It turns out that cells on ITO

Kerstin Schulze; Bert Maennig; Karl Leo; Yuto Tomita; Christian May; Jürgen Hüpkes; Eduard Brier; Egon Reinold; Peter Bäuerle

2007-01-01

29

Indium phosphide/cadmium sulfide thin-film solar cells. Final report, May 1979 through July 1980  

SciTech Connect

Thin-film InP/RXCdS/ITO/GLASS devices were prepared by depositing ITO on low-cost glass substrate, depositing CdS on the ITO by thermal evaporation, increasing the CdS lateral grain size by recrystallization, and depositing p-type InP by planar reactive deposition (PRD) on the recrystallized CdS (RXCdS). Yields of the RXCdS/ITO/GLASS substrates were increased to 90% with lateral dimensions of the RXCdS grains as large as 0.3 mm. P-type InP layers were obtained with Be doping. S-doping via vapor transport from the CdS was eliminated by capping the entire RXCdS substrate with InP. For InP deposited on RXCdS at 380/sup 0/C, devices showed blocking action with a barrier height of about 0.5 V but no light response, possibly due to an intermediate approx. 3-..mu..m-thick n-InP layer from diffusion of S from the RXCdS. These results were achieved despite poor InP epitaxy due to an approx. 0.5-..mu..m-thick In-Cd-S transition layer between the InP and the RXCdS. InP films were subsequently deposited on RXCdS at the reduced substrate temperature of 280/sup 0/C to reduce S-diffusion and improve the quality of the epitaxy. Complete InP epitaxy on RXCdS was achieved with the lateral dimensions of the InP (approx. = 40 ..mu..m) replicating that of the RXCdS. Given the increase in the concentration of n-type native defects as substrate temperature is decreased, the present lower limit for obtaining p-type InP by vacuum technologies appears to be about 300/sup 0/C. A 300 to 350/sup 0/C range of substrate temperature appears to befeasible for preparing large-grained p-type InP for both frontwall and backwall cell. However, if the thickness of the n-type layer due to S diffusion cannot be kept to less than a few thousand Angstroms, then development must be restricted to the frontwall cells.

Zanio, K.

1980-09-01

30

Zinc-doped gallium phosphide nanowires for photovoltaic structures  

NASA Astrophysics Data System (ADS)

The GaP-ZnO core-shell nanowire (NW) heterojunction integrated on top of a multi-junction solar cell can extend its spectral sensitivity region toward shorter wavelengths, enhance the photon absorption, and reduce the surface light reflection. We report on the preparation of the Zn-doped GaP cores for such heterostructure NWs. Problems with NW Zn doping are addressed. A small amount of diethylzinc (DEZn) vapor added to the reactor slightly increased the axial and radial growth rates, which resulted in moderate increase in NW tapering. A further increase in the DEZn molar fraction in the reactor suppressed the tapering (lower radial growth rate) but the axial growth rate was increased. When the DEZn molar fraction exceeded 9 × 10-6, the NW growth was hindered; only small stumps and kinked wires grew. The measurement of NW electrical transport parameters showed that DEZn compensated native n-type impurities at small vapor pressures (?DEZn ˜ 1 × 10-8 to 1 × 10-7); the NWs exhibited n-type conductivity or were compensated. GaP NWs of p-type with a hole concentration p ˜ 1 × 1018 cm-3 were grown only in a very narrow interval of DEZn vapor pressures (?DEZn ˜ 1-6 × 10-6).

Hasenöhrl, Stanislav; Eliáš, Peter; Šoltýs, Ján; Stoklas, Roman; Dujavová-Lauren?íková, Agáta; Novák, Jozef

2013-03-01

31

Microcrystalline single and double junction silicon based solar cells entirely prepared by HWCVD on textured zinc oxide substrate  

Microsoft Academic Search

Microcrystalline silicon based single junction pin and amorphous-microcrystalline double junction pinpin solar cells were fabricated entirely by hot-wire chemical vapor deposition on textured zinc oxide substrates. The short circuit current density for microcrystalline pin cells shows an increase of 20–25% compared to unetched zinc oxide, indicating a better light trapping on textured zinc oxide substrate. The best initial conversion efficiency

P. Kumar; M. Kupich; W. Bock; R. O. Dusane; B. Schroeder

2006-01-01

32

Small molecule solar cells based on a series of water-soluble zinc phthalocyanine donors.  

PubMed

Organic solar cells based on a series of water-soluble zinc phthalocyanines (wsZnPc) with varying numbers of sulfonate peripheral substituents and a C60 donor have been fabricated and characterised. We find that the number of substituents affects both the V(oc) and J(sc) of the devices, with the disulfonated wsZnPc devices performing best. PMID:22433974

Ryan, James William; Anaya-Plaza, Eduardo; de la Escosura, Andrés; Torres, Tomas; Palomares, Emilio

2012-03-20

33

Computational screening of functionalized zinc porphyrins for dye sensitized solar cells.  

PubMed

An efficient dye sensitized solar cell (DSSC) is one possible solution to meet the world's rapidly increasing energy demands and associated climate challenges. This requires inexpensive and stable dyes with well-positioned frontier energy levels for maximal solar absorption, efficient charge separation, and high output voltage. Here we demonstrate an extensive computational screening of zinc porphyrins functionalized with electron donating side groups and electron accepting anchoring groups. The trends in frontier energy levels versus side groups are analyzed and a no-loss DSSC level alignment quality is estimated. Out of the initial 1029 molecules, we find around 50 candidates with level alignment qualities within 5% of the optimal limit. We show that the level alignment of five zinc porphyrin dyes which were recently used in DSSCs with high efficiencies can be further improved by simple side group substitutions. All frontier energy levels, gaps and level alignment quality values are stored in a database publicly available. PMID:24129651

Ornsø, Kristian B; Garcia-Lastra, Juan M; Thygesen, Kristian S

2013-10-23

34

Thin film cadmium telluride, zinc telluride, and mercury zinc telluride solar cells  

Microsoft Academic Search

The first year was covered of a program to investigate: (1) the deposition of CdTe films by various techniques; (2) the deposition of transparent conducting semiconductor (TCS) films by various techniques; (3) the preparation and evaluation of thin film CdTe solar cells; and (4) the deposition and characterization of ZnTe films and heterojunctions. CdTe films were deposited on glass and

T. L. Chu

1989-01-01

35

Thin film cadmium telluride, zinc telluride, and mercury zinc telluride solar cells  

SciTech Connect

This report covers the first year of a program to investigate (1) the deposition of CdTe films by various techniques, (2) the deposition of transparent conducting semiconductor (TCS) films by various techniques, (3) the preparation and evaluation of thin-film CdTe solar cells, and (4) the deposition and characterization of ZnTe films and heterojunctions. CdTe films were deposited on glass and SnO{sub 2}/glass substrates by metal-organic chemical vapor deposition (MOCVD) by reacting dimethylcadmium (DMCd) with diisopropyltellurium (DITe) in H{sub 2}. The optical bandgap was 1.50 eV. The conductivity type of the films could be controlled by controlling the DMCd/DITe molar ratio in the reaction mixture. This is a promising technique for the preparation of thin-film CdTe homojunction solar cells. CdS films were deposited from aqueous solutions by reacting thiourea and cadmium acetate in an ammonical solution. The films show good optical transmission in the above-bandgap region but are porous and impure. The photovoltaic characteristics of cells employing solution-grown CdS films are therefore inferior to those employing vacuum-evaporated CdS films. Films of ZnO, ZnS, and ZnTe were deposited, via MOCVD, on glass and SnO{sub 2}/glass substrates, and ZnO/ZnTe heterojunctions were produced. Open-circuit voltages of 0.6--0.7 V were measured for ZnS/ZnTe heterojunctions. 14 refs., 21 figs., 3 tabs.

Chu, T.L. (University of South Florida, Tampa, FL (USA))

1989-10-01

36

Pulse-reverse electrodeposition of transparent nickel phosphide film with porous nanospheres as a cost-effective counter electrode for dye-sensitized solar cells.  

PubMed

A Ni2P nanolayer with porous nanospheres was directly coated on fluorine-doped tin oxide glass by pulse-reverse deposition as a low-cost counter electrode catalyst for dye-sensitized solar cells, and the photoelectron conversion efficiency of the cell was increased to 7.32% by using a porous nanosphere catalyst due to the significantly improved ion transport. PMID:24132176

Wu, Mao-Sung; Wu, Jia-Fang

2013-10-29

37

CdS/CdTe thin-film solar cell with a zinc stannate buffer layer  

NASA Astrophysics Data System (ADS)

This paper describes an improved CdS/CdTe polycrystalline thin-film solar-cell device structure that integrates a zinc stannate (Zn2SnO4 or ZTO) buffer layer between the transparent conductive oxide (TCO) layer and the CdS window layer. Zinc stannate films have a high bandgap, high transmittance, low absorptance, and low surface roughness. In addition, these films are chemically stable and exhibit higher resistivities that are roughly matched to that of the CdS window layer in the device structure. Preliminary device results have demonstrated that by integrating a ZTO buffer layer in both SnO2-based and Cd2SnO4 (CTO)-based CdS/CdTe devices, performance and reproducibility can be significantly enhanced.

Wu, X.; Sheldon, P.; Mahathongdy, Y.; Ribelin, R.; Mason, A.; Moutinho, H. R.; Coutts, T. J.

1999-03-01

38

Chemical Etching of Zinc Oxide for Thin-Film Silicon Solar Cells  

PubMed Central

Abstract Chemical etching is widely applied to texture the surface of sputter-deposited zinc oxide for light scattering in thin-film silicon solar cells. Based on experimental findings from the literature and our own results we propose a model that explains the etching behavior of ZnO depending on the structural material properties and etching agent. All grain boundaries are prone to be etched to a certain threshold, that is defined by the deposition conditions and etching solution. Additionally, several approaches to modify the etching behavior through special preparation and etching steps are provided.

Hupkes, Jurgen; Owen, Jorj I; Pust, Sascha E; Bunte, Eerke

2012-01-01

39

Highly efficient inverted polymer solar cells with reduced graphene-oxide-zinc-oxide nanocomposites buffer layer  

NASA Astrophysics Data System (ADS)

In this study, we reported a 36% improvement in the performance of inverted solar cells as a result of increased short-circuit current (JSC) obtained using a composition of zinc oxide (ZnO) and reduced graphene oxide (RGO) as an n-type buffer layer. RGO-ZnO nanocomposites show higher electron conductivity than intrinsic ZnO; moreover, they show reduced contact resistance at the interface between the active layer and n-type buffer layer. These factors prevent carrier loss resulting from defects and recombinations in the device, thereby significantly increasing the JSC value for the device. Thus, an efficiency of 4.15% was achieved for inverted solar cells with a controlled RGO-ZnO nanocomposites layer.

Woo Lee, Hyun; Young Oh, Jin; Il Lee, Tae; Soon Jang, Woo; Bum Yoo, Young; Sang Chae, Soo; Ho Park, Jee; Min Myoung, Jae; Moon Song, Kie; Koo Baik, Hong

2013-05-01

40

Development of Novel Aluminum-Doped Zinc Oxide Film and Its Application to Solar Cells  

NASA Astrophysics Data System (ADS)

We have developed novel aluminum-doped zinc oxide films (AZO-X and AZO-HX films) with a high haze value using wet-chemical etching for various times after dc magnetron sputtering, and have investigated their electrical and optical properties, durability under high-humidity condition, and surface morphology. The AZO-X and AZO-HX films showed good balance between transmittance in the near-infrared area and durability under 85 °C--85%RH condition. These novel films also had a higher haze value after wet chemical etching than normal AZO films. The crater size and haze value of the AZO-HX film increased with increasing etching time in comparison with those of the AZO-X film. The haze value of the AZO-HX film was higher than that of the AZO-X film; their values are 90% at 550 nm and 60% at 800 nm. Furthermore, the AZO-HX film was applied in amorphous silicon (a-Si) single-type solar cells as the front electrode. The short-circuit current of the solar cell using the AZO-HX film was higher than that of the solar cell using the AZO-X film. As an optimization-based result, an efficiency as high as 10.2% was obtained, showing that the new AZO-HX film is a promising material for the front electrode of a-Si solar cells.

Kuramochi, Hideto; Akiike, Ryo; Iigusa, Hitoshi; Tamano, Kimiaki; Utsumi, Kentaro; Shibutami, Tetsuo; Sichanugrist, Porponth; Konagai, Makoto

2012-10-01

41

Enhanced performance by incorporation of zinc oxide nanowire array for organic-inorganic hybrid solar cells  

NASA Astrophysics Data System (ADS)

We study the solar power conversion efficiency in hybrid solar cells based on zinc oxide (ZnO)/antimony trisulfide (Sb2S3)/poly-3(hexylthiophene) heterojunctions. The incorporation of ZnO nanowire arrays (NAs) structure results in power conversion efficiency of 2.9%, or 20% higher than the control device. Absorption spectra and numerical simulation analysis provide strong evidence revealing that the enhanced performance is mainly induced by (1) enhanced optical absorption from light-trapping effect of NAs and (2) reduced bulk recombination rate in Sb2S3 from shortened electron injection pathway into ZnO. Significantly, numerical simulations show that the expected interface recombination increase from larger interfacial area effects is negligible.

Liu, C. P.; Chen, Z. H.; Wang, H. E.; Jha, S. K.; Zhang, W. J.; Bello, I.; Zapien, J. A.

2012-06-01

42

Synthesis of titanium dioxide and zinc oxide nanowires for excitonic solar cells  

NASA Astrophysics Data System (ADS)

Dye-sensitized, quantum-dot sensitized, quantum-dot, and hybrid organic/inorganic solar cells are promising excitonic photovoltaic devices for the generation of low cost, carbon free energy. Wide-band gap semiconductor nanowire photoanodes have the potential to increase the efficiencies of these excitonic solar cells. Controlling and tailoring the dimensions of the nanowires (i.e. nanowire height, diameter, and planar number density) for each solar cell type is important for efficiency improvement. Obtaining such control will require a detailed and fundamental understanding of the nanowire growth process. Towards this end, the synthesis of TiO2 and ZnO nanowire films in aqueous solutions was studied. Anatase TiO2 nanowire films were grown on flexible titanium foil substrates using a three step hydrothermal synthesis. First, the top surface of the titanium foil was transformed to Na2Ti2O 4(OH)2 nanotubes through hydrothermal oxidation in NaOH. Next, the Na2Ti2O4(OH)2 nanotubes were converted to H2Ti2O4(OH)2 nanotubes by ion exchange. Finally, the H2Ti2O 4(OH)2 nanotubes were converted to polycrystalline anatase nanowires through a topotactic transformation. The film morphology evolution, crystal structure transformations, and growth mechanism were examined in detail. Dye-sensitized solar cells (DSSCs) were assembled from these TiO 2 nanowire films. Transient photocurrent and photovoltage spectroscopies were used to measure the electron transport and recombination rates in these solar cells. Compared to TiO2 nanoparticle DSSCs the electron collection efficiency in the TiO2 nanowire DSSCs was increased due to decreased electron recombination. However, the electron transport in the nanowire DSSCs was similar to that of TiO2 nanoparticle DSSCs. The synthesis of ZnO nanowires from aqueous solutions of methenamine (HMT) and zinc nitrate hexahydrate on substrates was studied in detail. A ZnO nanowire growth mechanism was proposed which predicts that the precursor is a zinc-methenamine complex (Zn-HMT2+ and Zn-HMT-Zn 4+) which reacts at the hydroxyl terminated nanowire surface. This growth mechanism was supported by examining the growth with several experimental techniques, kinetic modeling, and thermodynamic calculations. In addition, the ZnO nanowire film growth, on ZnO seeded substrates, was found to be mass transport limited. This results in an inverse relationship between the nanowire planar number density and the height and diameter of the nanowires. By stirring the solution the growth rate is increased by approximately a factor of four.

Boercker, Janice Elaine

43

Structure-function relationships in unsymmetrical zinc phthalocyanines for dye-sensitized solar cells.  

PubMed

A series of unsymmetrical zinc phthalocyanines bearing an anchoring carboxylic function linked to the phthalocyanine ring through different spacers were designed for dye-sensitised solar cells (DSSC). The modification of the spacer group allows not only a variable distance between the dye and the nanocrystalline TiO(2), but also a distinct orientation of the phthalocyanine on the semiconductor surface. The photovoltaic data show that the nature of the spacer group plays a significant role in the electron injection from the photo-excited dye into the nanocrystalline TiO(2) semiconductor, the recombination rates and the efficiency of the cells. The incident monochromatic photon-to-current conversion efficiency (IPCE) for phthalocyanines bearing an insulating spacer is as low as 9%, whereas for those with a conducting spacer an outstanding IPCE 80% was obtained. PMID:19338034

Cid, Juan-José; García-Iglesias, Miguel; Yum, Jun-Ho; Forneli, Amparo; Albero, Josep; Martínez-Ferrero, Eugenia; Vázquez, Purificación; Grätzel, Michael; Nazeeruddin, Mohammad K; Palomares, Emilio; Torres, Tomás

2009-01-01

44

Property control of expanding thermal plasma deposited textured zinc oxide with focus on thin film solar cell applications  

Microsoft Academic Search

Property control of expanding thermal plasma deposited textured zinc oxide is demonstrated considering intrinsic, i.e. bulk, and extrinsic transparent conducting oxide quality relevant for application in thin film amorphous silicon pin solar cells. Particularly the interdependence of electrical conductivity, film composition and film morphology, i.e. structure, feature shape and roughness of the surface, is addressed. Control of film composition is

R. Groenen; J. Loffler; J. L. Linden; R. E. I. Schropp

2005-01-01

45

Photoelectrochemical cell having photoanode with thin boron phosphide coating as a corrosion resistant layer  

SciTech Connect

A surface prone to corrosion in corrosive environments is rendered anticorrosive by CVD growing a thin continuous film, e.g., having no detectable pinholes, thereon, of boron phosphide. In one embodiment, the film is semiconductive. In another aspect, the invention is an improved photoanode, and/or photoelectrochemical cell with a photoanode having a thin film of boron phosphide thereon rendering it anticorrosive, and providing it with unexpectedly improved photoresponsive properties.

Baughman, R.S.; Ginley, D.S.

1984-03-20

46

Photoelectrochemical cell having photoanode with thin boron phosphide coating as a corrosion resistant layer  

DOEpatents

A surface prone to corrosion in corrosive environments is rendered anticorrosive by CVD growing a thin continuous film, e.g., having no detectable pinholes, thereon, of boron phosphide. In one embodiment, the film is semiconductive. In another aspect, the invention is an improved photoanode, and/or photoelectrochemical cell with a photoanode having a thin film of boron phosphide thereon rendering it anitcorrosive, and providing it with unexpectedly improved photoresponsive properties.

Baughman, Richard J. (Albuquerque, NM); Ginley, David S. (Albuquerque, NM)

1984-01-01

47

Zinc-porphyrin based dyes for dye-sensitized solar cells.  

PubMed

We have designed seven efficient sensitizers based on the zinc-porphyrin structure for dye sensitized solar cells (DSSCs). The geometries, electronic properties, light harvesting efficiency (LHE), and electronic absorption spectra of these sensitizers are studied using density functional theory (DFT) and time-dependent density functional theory (TD-DFT) calculations. We found that the designed sensitizers have smaller HOMO-LUMO energy with broadened and red-shifted absorption bands (300-1100 nm) having high molar extinction coefficient compared to the so far known best sensitizer (YD2-o-C8). The position of HOMO-LUMO energy level of these sensitizers ensures a positive effect on the process of electron injection and dye regeneration. Our theoretical calculations reveal that the new sensitizer can be used as a potential sensitizer for DSSCs compared to YD2-o-C8. PMID:24090130

Karthikeyan, S; Lee, Jin Yong

2013-10-14

48

Design and fabrication of anti-reflection coating on Gallium Phosphide, Zinc Selenide and Zinc Sulfide substrates for visible and infrared application  

NASA Astrophysics Data System (ADS)

Results of design and fabrication of a dual-band anti-reflection coating on a gallium phosphide (GaP), zinc selenide (ZnSe) and zinc sulfide (ZnS) substrates are presented. A multilayer stack structure of antireflection coatings made of zinc sulfide and yttrium fluoride (YF3) was theoretically designed for optical bands between 0.8 and 0.9 ?m and between 9.5 and 10.5 ?m. This stack was designed as efficient for these materials (GaP, ZnS, ZnSe) together. Multilayer stack structure was deposited using thermal evaporation method. Theoretically predicted transmittance spectra were compared with transmitted spectra measured on coated substrates. Efficiency of anti-reflection coating is estimated and discrepancies are analyzed and discussed.

Vápenka, D.; Václavík, J.; Mokrý, P.

2013-04-01

49

Synthesis of high quality zinc-blende CdSe nanocrystals and their application in hybrid solar cells  

Microsoft Academic Search

Oleic acid (OA) modified zinc-blende cadmium selenium nanocrystals (NCs) with different diameters, 3–5 nm, have been prepared. We find that the morphology and fluorescent properties of the samples are related to the preparation conditions such as the chain-length and concentration of the cadmium precursor as well as the concentration of OA. The hybrid solar cells based on the obtained spherical

Lili Han; Donghuan Qin; Xi Jiang; Yanshan Liu; Li Wang; Junwu Chen; Yong Cao

2006-01-01

50

Zinc oxide multilayers for solar collector coatings  

Microsoft Academic Search

A solar selective coating has been fabricated by capping black zinc oxide with a transparent zinc oxide heat mirror film. Deposition onto glass substrates was accomplished by reactive bias sputtering. The zinc oxide multilayer structure had a solar absorptance of 0.90 and an IR emittance of 0.26. Suggestions are made for significant improvement of solar selective performance.

M. J. Brett; R. R. Parsons; H. P. Baltes

1986-01-01

51

Synthesis of titanium dioxide and zinc oxide nanowires for excitonic solar cells  

Microsoft Academic Search

Dye-sensitized, quantum-dot sensitized, quantum-dot, and hybrid organic\\/inorganic solar cells are promising excitonic photovoltaic devices for the generation of low cost, carbon free energy. Wide-band gap semiconductor nanowire photoanodes have the potential to increase the efficiencies of these excitonic solar cells. Controlling and tailoring the dimensions of the nanowires (i.e. nanowire height, diameter, and planar number density) for each solar cell

Janice Elaine Boercker

2009-01-01

52

Novel nanostructure zinc zirconate, zinc oxide or zirconium oxide pastes coated on fluorine doped tin oxide thin film as photoelectrochemical working electrodes for dye-sensitized solar cell.  

PubMed

Zinc zirconate (ZnZrO(3)) (ZZ), zinc oxide (ZnO) (ZO) and zirconium oxide (ZrO(2)) (ZRO) nano-particles were synthesized by simple sol-gel method. ZZ, ZO and ZRO nano-particles were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD) and UV-Vis diffuse reflectance spectrum (DRS). Nanoporous ZZ, ZO and ZRO thin films were prepared doctor blade technique on the fluorine-doped tin oxide (FTO) and used as working electrodes in dye sensitized solar cells (DSSC). Their photovoltaic behavior were compared with standard using D35 dye and an electrolyte containing [Co(bpy)(3)](PF(6))(2), [Co(pby)(3)](PF(6))(3), LiClO(4), and 4-tert-butylpyridine (TBP). The properties of DSSC have been studied by measuring their short-circuit photocurrent density (Jsc), open-circuit voltage (VOC) and fill factor (ff). The application of ZnZrO(3) as working electrode produces a significant improvement in the fill factor (ff) of the dye-sensitized solar cells (ff=56%) compared to ZnO working electrode (ff=40%) under the same condition. PMID:23266694

Hossein Habibi, Mohammad; Askari, Elham; Habibi, Mehdi; Zendehdel, Mahmoud

2012-12-05

53

Novel nanostructure zinc zirconate, zinc oxide or zirconium oxide pastes coated on fluorine doped tin oxide thin film as photoelectrochemical working electrodes for dye-sensitized solar cell  

NASA Astrophysics Data System (ADS)

Zinc zirconate (ZnZrO3) (ZZ), zinc oxide (ZnO) (ZO) and zirconium oxide (ZrO2) (ZRO) nano-particles were synthesized by simple sol-gel method. ZZ, ZO and ZRO nano-particles were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD) and UV-Vis diffuse reflectance spectrum (DRS). Nanoporous ZZ, ZO and ZRO thin films were prepared doctor blade technique on the fluorine-doped tin oxide (FTO) and used as working electrodes in dye sensitized solar cells (DSSC). Their photovoltaic behavior were compared with standard using D35 dye and an electrolyte containing [Co(bpy)3](PF6)2, [Co(pby)3](PF6)3, LiClO4, and 4-tert-butylpyridine (TBP). The properties of DSSC have been studied by measuring their short-circuit photocurrent density (Jsc), open-circuit voltage (VOC) and fill factor (ff). The application of ZnZrO3 as working electrode produces a significant improvement in the fill factor (ff) of the dye-sensitized solar cells (ff = 56%) compared to ZnO working electrode (ff = 40%) under the same condition.

Hossein Habibi, Mohammad; Askari, Elham; Habibi, Mehdi; Zendehdel, Mahmoud

2013-03-01

54

The kinetics of oxidative alcoholysis of zinc phosphide in the presence of oxygen and the FeCl3-I2 mixed catalyst in solution in butanol  

NASA Astrophysics Data System (ADS)

The oxidative alkoxylation of zinc phosphide to tributyl phosphate occurred at a high rate and with high selectivity in a solution of FeCl3-I2 in butanol at 50-70°C. The kinetic characteristics and optimum conditions of the process were determined. The experimental and literature data were used to identify key stages of the formation of tributyl phosphate in the presence of the mixed catalytic system.

Ibraimova, Zh. U.; Polimbetova, G. S.; Aleshkova, M. M.; Borangazieva, A. K.

2009-05-01

55

Air-stable inverted flexible polymer solar cells using zinc oxide nanoparticles as an electron selective layer  

NASA Astrophysics Data System (ADS)

The performance and stability of unencapsulated inverted bulk-heterojunction solar cells with zinc oxide (ZnO) made by different processes as the electron selective contact are compared to conventional bulk-heterojunction solar cells. The low temperature processed inverted devices using ZnO nanoparticles on indium tin oxide plastic substrates showed high power conversion efficiency of ~3.3%. This inverted device structure possessed much better stability under ambient conditions retaining over 80% of its original conversion efficiency after 40 days while the conventional one showed negligible photovoltaic activity after 4 days. This is due to the improved stability at the poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate)/Ag interface.

Hau, Steven K.; Yip, Hin-Lap; Baek, Nam Seob; Zou, Jingyu; O'Malley, Kevin; Jen, Alex K.-Y.

2008-06-01

56

Oxide Solar Cells Fabricated Using Zinc Oxide and Plasma-Oxidized Cuprous Oxide  

NASA Astrophysics Data System (ADS)

Oxide heterojunction solar cells composed of an n-type Al-doped ZnO (AZO) thin film on the surfaces of p-type Cu2O films were fabricated. The Cu2O films of about 0.34 to 1.67 ?m thickness were grown by partial oxidation of a Cu sheet using microwave plasma. The AZO film of 400 nm thickness was deposited by magnetron sputtering. Energy conversion efficiencies of 0.12 to 0.30% were obtained in AZO/Cu2O cells under AM1.5 solar illumination.

Chan, Yi-Ming; Wu, Ya-Ting; Jou, Shyankay

2012-12-01

57

A review of episodes of zinc phosphide toxicosis in wild geese (Branta spp.) in Oregon (2004?2011)  

USGS Publications Warehouse

Epizootic mortality in several geese species, including cackling geese (Branta hutchinsii) and Canada geese (Branta canadensis), has been recognized in the Willamette Valley of Oregon for over a decade. Birds are generally found dead on a body of water or are occasionally observed displaying neurologic clinical signs such as an inability to raise or control the head prior to death. Investigation of these epizootic mortality events has revealed the etiology to be accidental poisoning with the rodenticide zinc phosphide (Zn3P2). Gross and histologic changes are restricted to acute pulmonary congestion and edema, sometimes accompanied by distension of the upper alimentary tract by fresh grass. Geese are unusually susceptible to this pesticide; when combined with an epidemiologic confluence of depredation of specific agricultural crops by rodents and seasonal avian migration pathways, epizootic toxicosis may occur. Diagnosis requires a high index of suspicion, appropriate sample collection and handling, plus specific test calibration for this toxicant. Interagency cooperation, education of farmers regarding pesticide use, and enforcement of regulations has been successful in greatly decreasing these mortality events since 2009.

Bildfell, Rob J.; Rumbeiha, Wilson K.; Schuler, Krysten L.; Meteyer,Carol U.; Wolff, Peregrine L.; Gillin, Colin M.

2013-01-01

58

Enhancing the efficiency of SnS solar cells via band-offset engineering with a zinc oxysulfide buffer layer  

NASA Astrophysics Data System (ADS)

SnS is a promising earth-abundant material for photovoltaic applications. Heterojuction solar cells were made by vapor deposition of p-type tin(II) sulfide, SnS, and n-type zinc oxysulfide, Zn(O,S), using a device structure of soda-lime glass/Mo/SnS/Zn(O,S)/ZnO/ITO. A record efficiency was achieved for SnS-based thin-film solar cells by varying the oxygen-to-sulfur ratio in Zn(O,S). Increasing the sulfur content in Zn(O,S) raises the conduction band offset between Zn(O,S) and SnS to an optimum slightly positive value. A record SnS/Zn(O,S) solar cell with a S/Zn ratio of 0.37 exhibits short circuit current density (Jsc), open circuit voltage (Voc), and fill factor (FF) of 19.4 mA/cm2, 0.244 V, and 42.97%, respectively, as well as an NREL-certified total-area power-conversion efficiency of 2.04% and an uncertified active-area efficiency of 2.46%.

Sinsermsuksakul, Prasert; Hartman, Katy; Bok Kim, Sang; Heo, Jaeyeong; Sun, Leizhi; Hejin Park, Helen; Chakraborty, Rupak; Buonassisi, Tonio; Gordon, Roy G.

2013-02-01

59

A DFT study of the regeneration process of zinc porphyrin analogues in dye-sensitized solar cells.  

PubMed

The regeneration reaction of sensitizers in dye-sensitized solar cells is one of the critical steps in photonic chemical circuits. In this report, the two-step regeneration reaction of a series of zinc porphyrin sensitizers with a variety of substituent groups, i.e., CN-, F-, Cl-, H-, PhCH3-, OH- and NH2- groups, has been studied using density functional theory (DFT). The effects of the substituent groups on the structures of zinc porphyrin sensitizers, the regeneration intermediates and the reaction thermodynamics and kinetics have been explored. It is found that substituent groups at meso-position of zinc porphyrins strongly influenced the mode of two-step regeneration. For Por-CN, Por-F and Por-Cl, the formation of DyeI(Zn) and DyeI(Zn)-I intermediates are dominant, whereas for Por-H, Por-PhCH3 and Por-OH, the formation of DyeI(Py) and DyeI(Py)-I intermediates predominate. Due to the stronger electron-withdrawing effect of CN- and F-, the corresponding Por-CN and Por-F have no energy barrier in reaction. This suggests that their regeneration should be faster than the others. Besides two-step regeneration, alternative regenerations including one-step regeneration and reductive quenching reaction of excited dye and the influences of substituent groups on the electron injection efficiency are also estimated. These results provide valuable information for the design of novel zinc porphyrin analogues for DSCs. PMID:23913241

Yang, Fan; Zhang, Zidan; He, Xuehao

2013-08-02

60

Nitrogen Doped Zinc Telluride Back Contact to CdS/CdTe Solar Cells  

NASA Astrophysics Data System (ADS)

We describe the development of the Nitrogen doped ZnTe for the back contacts of CdS/CdTe solar cell. Reproducible p-ZnTe films were obtained using RF magnetron sputtering technique with Ar/N2 gas mixture. Both, intrinsic and nitrogen doped, ZnTe films were investigated for electronic properties. The conductivity of the N:ZnTe films was about five orders of magnitude higher than that of intrinsic ones. A bilayer of intrinsic and doped ZnTe films were used in back contact structure of CdS/CdTe solar cells. The ZnTe/N:ZnTe/Ni structure showed slightly lower initial performance but better stability in comparison to evaporated Cu/Au back contacts.

Drayton, J.; Makhratchev, K.; Price, K. J.; Ma, X.; Simmons, D. A.; Ludwig, K.; Gupta, A.; Bohn, R. G.; Compaan, A. D.

2000-10-01

61

Effect of coadsorbent on the photovoltaic performance of zinc pthalocyanine-sensitized solar cells.  

PubMed

The effect of chenodeoxycholic acid as a coadsorbent on TiO 2 nanocrystalline solar cells incorporating phthalocyanine sensitizers was studied under various conditions. Adding chenodeoxycholic acid onto TiO 2 nanoparticles not only reduces the adsorption of phthalocyanine sensitizers but also prevents sensitizer aggregation, leading to different photovoltaic performance. The inspection of IPCE and absorption spectra showed that the load of phthalocyanine sensitizers is strongly dependent on the molar concentration of chenodeoxycholic acid coadsorbent. The open circuit voltage of the solar cells with chenodeoxycholic acid coadsorbent increases due to the enhanced electron lifetime in TiO 2 nanoparticles coupled with the band edge shift of TiO 2 to negative potentials. PMID:18435553

Yum, Jun-Ho; Jang, Song-Rim; Humphry-Baker, Robin; Grätzel, M; Cid, Juan-José; Torres, Tomas; Nazeeruddin, Md K

2008-04-25

62

Solution-processable zinc oxide for the polymer solar cell based on P3HT:PCBM.  

PubMed

The device performance of polymer solar cells with zinc oxide (ZnO) nanoparticles inserted as an electron injection layer between the poly(3-hexylthiopene) (P3HT):phenyl-C60-butyric acid methyl ester (PCBM) active layer and the Al electrode was studied. The polymer solar cell consists of molybdenum-oxide (MoO3) as a hole injection layer, P3HT:PCBM bulk heterojunction as an active layer, and ZnO NPs as an electron injection layer. The ZnO layer was formed from a precursor solution on the top part of the P3HT:PCBM film (1:0.8 weight ratio) via sol-gel spin-coating, and was annealed at a low temperature (150 degrees C). The crystallinity, the atomic ratio of Zn and O, the absorption spectra, and the surface morphology of the ZnO thin films were studied. The device with a ZnO layer showed 9-11% higher J(SC) and 8-9% higher PCE compared to the devices without a ZnO layer. These improved device properties are attributed to the efficient electron extraction and the decreased reflectivity owing to the use of a ZnO layer. PMID:22121646

Kim, Jun Young; Noh, Seunguk; Lee, Donggu; Nayak, Pradipta K; Hong, Yongtaek; Lee, Changhee

2011-07-01

63

High efficiency cadmium telluride and zinc telluride based thin-film solar cells  

SciTech Connect

This report describes work to improve the basic understanding of CdTe and ZnTe alloys by growing and characterizing these films along with cell fabrication. The major objective was to develop wide-band-gap (1.6--1.8 eV) material for the top cell, along with compatible window material and transparent ohmic contacts, so that a cascade cell design can be optimized. Front-wall solar cells were fabricated with a glass/SnO{sub 2}/CdS window, where the CdS film is thin to maximize transmission and current. Wide-band-gap absorber films (E{sub g} = 1.75 eV) were grown by molecular beam epitaxy (MBE) and metal-organic chemical vapor deposition (MOCVD) techniques, which provided excellent control for tailoring the film composition and properties. CdZnTe films were grown by both MBE and MOCVD. All the as-grown films were characterized by several techniques (surface photovoltage spectroscopy, Auger electron spectroscopy (AES), and x-ray photoelectron spectroscopy (XPS)) for composition, bulk uniformity, thickness, and film and interface quality. Front-wall-type solar cells were fabricated in collaboration with Ametek Materials Research Laboratory using CdTe and CdZnTe polycrystalline absorber films. The effects of processing on ternary film were studied by AES and XPS coupled with capacitance voltage and current voltage measurements as a function of temperature. Bias-dependent spectral response and electrical measurements were used to test some models in order to identify and quantify dominant loss mechanisms.

Rohatgi, A.; Sudharsanan, R.; Ringel, S.A.; Chou, H.C. (Georgia Inst. of Tech., Atlanta, GA (United States))

1992-10-01

64

Growth of chalcopyrite-structure semiconductors zinc tin arsenide and zinc tin phosphide by molecular beam epitaxy  

NASA Astrophysics Data System (ADS)

Present work is focused on the epitaxial growth of two closely related compounds: ZnSnAS2 and ZnSnP2. We focus on two structural modifications in which these materials can be obtained---the ordered structure (known as chalcopyrite) and the disordered (sphalerite) equivalent with the same macroscopic composition. To our knowledge no one has applied modern growth techniques to the epitaxial growth of AIIBIVCV2 materials in order to obtain high quality thin films. We decided to investigate the growth of thin films of ZnSnAs2 and ZnSnP2 using gas source molecular beam epitaxy (GS MBE). The most interesting property of ZnSnP2 is a large difference in the bandgap of material depending on the degree of ordering. The bandgap of bulk crystal can change by up to 0.42 eV simply by variation of the growth conditions. Custom designed MBE system was constructed to provide the necessary growth precursors. Conventional Knudsen cells were build to evaporate zinc, tin and arsenic. Gas lines were added later to supply phosphorus and arsenic. To determine the initial growth condition evaporation experiments were carried out using small pieces of bulk ZnSnP2. Optimum growth temperature was determined be in the range of 300--350°C. After the optimization of the growth process high quality epitaxial layers of ZnSnAs2 were grown on InP(001) substrates with the lattice mismatch of 3.4·10--4 . Following the developed procedures epitaxial ZnSnP2 was grown on GaAs(001) substrates. We observed a transition from the sphalerite to the chalcopyrite structure with increasing Sn/Zn flux ratio. This transition was investigated in detail by high resolution X-ray diffraction. Room temperature luminescence was observed on partially ordered samples at 1.35 eV. The growth model of ordered and disordered materials was suggested. High quality superlattices containing sphalerite structure ZnSnP 2 layers and GaAs spacers were grown to demonstrate the possibility of the epitaxial regrowth. In order to obtain quaternary compounds a mixture of arsine and phosphine was used to obtain ZnSn(AsxP1-x) 2 in a wide range of compositions.

Seryogin, Georgiy A.

2000-10-01

65

High-efficiency cadmium and zinc-telluride-based thin-film solar cells  

SciTech Connect

This report describes research into polycrystalline CdTe solar cells grown by metal-organic chemical vapor deposition. Efficiencies of {approximately}10% were achieved using both p-i-n and p-n structures. A pre-heat treatment of CdS/SnO{sub 2}/glass substrates at 450{degrees}C in hydrogen atmosphere prior to the CdTe growth was found to be essential for high performance because this heat treatment reduces oxygen-related defects from the CdS surface. However, this treatment also resulted in a Cd-deficient CdS surface, which may in part limit the CdTe cell efficiency to 10% due to Cd vacancy-related interface defects. Preliminary model calculations suggest that removing these states can increase the cell efficiency from 10% to 13.5%. Photon absorption in the CdS film also limits the cell performance, and eliminating this loss mechanism can result in CdTe efficiencies in excess of 18%. Polycrystalline, 1.7-e, CdZnTe films were also grown for tandem-cell applications. CdZnTe/CdS cells processed using the standard CdTe cell fabrication procedure resulted in 4.4% efficiency, high series resistance, and a band-gap shift to 1.55 eV. The formation of Zn-O at and near the CdZnTe surface is the source of high contact resistance. A saturated dichromate each prior to contact deposition was found to solve the contact resistance problem. The CdCl{sub 2} treatment was identified as the cause of the observed band-gap shift due to the preferred formation of ZnCl{sub 2}. 59 refs.

Rohatgi, A.; Sudharsanan, R.; Ringel, S. (Georgia Inst. of Tech., Atlanta, GA (United States))

1992-02-01

66

Electrochemical deposition of zinc oxide films from non-aqueous solution: a new buffer\\/window process for thin film solar cells  

Microsoft Academic Search

Zinc oxide is a wide band gap semiconductor with wide application in thin film devices such as n-type window layers for thin film solar cells, piezoelectric and luminescent devices, and for catalytic applications. We have cathodically electrodeposited films of ZnO by reduction of dissolved oxygen in a non-aqueous solution (dimethylsulfoxide) containing a Zn salt. This method allows a large deposition

D. Gal; G Hodes; D Lincot; H.-W Schock

2000-01-01

67

Convergent synthesis of near-infrared absorbing, "push-pull", bisthiophene-substituted, zinc(II) phthalocyanines and their application in dye-sensitized solar cells.  

PubMed

Zinc(II) phthalocyanine dyes that contain triarylamine-terminated bisthiophene and hexylbisthiophene groups have been synthesized by a convergent approach by using carboxytriiodo-ZnPc as a precursor. Further transformation of the iodo groups by a Pd-catalyzed reaction allowed easy preparation of further extended ?-conjugated carboxy-ZnPcs. These dyes have been used as sensitizers in dye-sensitized solar cells, which exhibit a panchromatic response and moderate overall efficiencies. PMID:22473900

Ince, Mine; Cardinali, François; Yum, Jun-Ho; Martínez-Díaz, M Victoria; Nazeeruddin, Mohammad K; Grätzel, Michael; Torres, Tomás

2012-03-30

68

P/N Inp Solar Cells on Ge Wafers.  

National Technical Information Service (NTIS)

Indium phosphide (InP) P-on-N one-sun solar cells were epitaxially grown using a metalorganic chemical vapor deposition process on germanium (Ge) wafers. The motivation for this work is to replace expensive InP wafers, which are fragile and must be thick ...

S. Wojtczuk S. Vernon E. A. Burke

1994-01-01

69

Dye-sensitized solar cell characteristics of nanocomposite zinc ferrite working electrode: effect of composite precursors and titania as a blocking layer on photovoltaic performance.  

PubMed

This research investigates the performance of a zinc ferrite (ZF) as working electrodes in a dye-sensitized solar cell (DSSC). This ZF working electrode was prepared by sol-gel and thermal decomposition of four different precursors including: zinc acetate dihydrate (Zn(CH3COO)2·2H2O), ferric nitrate nonahydrate (Fe(NO3)3·9H2O), iron(III) acetate; Fe(C2H3O2)3, and zinc nitrate hexahydrate, Zn(NO3)2·6H2O. The effects of annealing temperature and precursors on the structural, morphological, and optical properties were investigated. The field emission scanning electron microscope images (FESEM) and scanning electron microscopy (SEM) show that ZFe films are polycrystalline in nature and homogeneous with densely packed grains. Nanoporous zinc ferrite coatings were prepared by doctor blade technique on the fluorine-doped tin oxide (FTO) and used as working electrodes in DSSC. In all DSSCs, platinized FTO and [Co(bpy)3](2+/3+) in 3-methoxy proponitrile were used as counter electrode and redox mediator system respectively. Comparing the fill factors of four different zinc ferrite nanocomposites, the highest fill factor was for ZnFe2O4-TBL sample. Cell fabricated with ZnFeA working electrode shows relatively higher Jsc. PMID:23571086

Habibi, Mohammad Hossein; Habibi, Amir Hossein; Zendehdel, Mahmoud; Habibi, Mehdi

2013-03-21

70

Dye-sensitized solar cell characteristics of nanocomposite zinc ferrite working electrode: Effect of composite precursors and titania as a blocking layer on photovoltaic performance  

NASA Astrophysics Data System (ADS)

This research investigates the performance of a zinc ferrite (ZF) as working electrodes in a dye-sensitized solar cell (DSSC). This ZF working electrode was prepared by sol-gel and thermal decomposition of four different precursors including: zinc acetate dihydrate (Zn(CH3COO)2?2H2O), ferric nitrate nonahydrate (Fe(NO3)3?9H2O), iron(III) acetate; Fe(C2H3O2)3, and zinc nitrate hexahydrate, Zn(NO3)2?6H2O. The effects of annealing temperature and precursors on the structural, morphological, and optical properties were investigated. The field emission scanning electron microscope images (FESEM) and scanning electron microscopy (SEM) show that ZFe films are polycrystalline in nature and homogeneous with densely packed grains. Nanoporous zinc ferrite coatings were prepared by doctor blade technique on the fluorine-doped tin oxide (FTO) and used as working electrodes in DSSC. In all DSSCs, platinized FTO and [Co(bpy)3]2+/3+ in 3-methoxy proponitrile were used as counter electrode and redox mediator system respectively. Comparing the fill factors of four different zinc ferrite nanocomposites, the highest fill factor was for ZnFe2O4-TBL sample. Cell fabricated with ZnFeA working electrode shows relatively higher Jsc.

Habibi, Mohammad Hossein; Habibi, Amir Hossein; Zendehdel, Mahmoud; Habibi, Mehdi

2013-06-01

71

Aggregation of zinc oxide nanoparticles: From non-aqueous dispersions to composites used as photoactive layers in hybrid solar cells  

Microsoft Academic Search

Hybrid solar cells are third-generation solar cells that are colloidal in nature. The composites used as photoactive layers within hybrid solar cells comprise conjugated polymers and inorganic semiconductor nanoparticles (e.g., nanocrystals and nanorods). The composites are usually prepared by spin casting non-aqueous dispersions consisting of polymer, nanoparticles and a co-solvent blend. The factors governing colloidal stability of the dispersions used

R. Rhodes; M. Horie; H. Chen; Z. Wang; M. L. Turner; B. R. Saunders

2010-01-01

72

InP Solar Cell Development on Inexpensive Si Substrates. Phase 1.  

National Technical Information Service (NTIS)

Indium phosphide (InP) solar cells were made on silicon (Si) wafers to take advantage of both the radiation-hardness properties of the InP solar cell and the light weight and cost savings of Si wafers compared to either InP or germanium (Ge) wafers. Calcu...

S. J. Wojtczuk

1995-01-01

73

Cost-Effective and Self-Textured Gallium-Doped Zinc Oxide Front Contacts for Hydrogenated Amorphous Silicon Thin-Film Solar Cells  

NASA Astrophysics Data System (ADS)

We adopt a economical and original method to fabricate self-textured gallium-doped zinc oxide (GZO) front contacts for hydrogenated amorphous silicon (a-Si:H) single-junction solar cells. This technique involves an atmospheric-pressure plasma jet (APPJ) and a dc sputtering process. The electro-optical characteristics of the textured GZO films are mainly controlled by the haze of organosilicon underlayers deposited by the APPJ. The films exhibit an average optical transmittance of about 80% and resistivity below 9.91× 10-4 ? cm. Moreover, compared with flat solar cells, textured cells fabricated on moderate GZO front contacts show 7.9 and 10.9% enhancements in conversion efficiency and short-circuit current density, respectively.

Yu, Shu-Hung; Ho, Po-Ching; Lee, Chia-Ling; Bi, Chien-Chung; Yeh, Chih-Hung; Chang, Chun-Yen

2013-02-01

74

Development of highly efficient thin film silicon solar cells on texture-etched zinc oxide-coated glass substrates  

Microsoft Academic Search

ZnO films prepared by magnetron sputtering on glass substrates and textured by post-deposition chemical etching are applied as substrates for p–i–n solar cells. Using both rf and dc sputtering, similar surface textures can be achieved upon etching. Excellent light trapping is demonstrated by high quantum efficiencies at long wavelengths for microcrystalline silicon solar cells. Applying an optimized microcrystalline\\/amorphous p-layer design,

J Müller; O Kluth; S Wieder; H Siekmann; G Schöpe; W Reetz; O Vetterl; D Lundszien; A Lambertz; F Finger; B Rech; H Wagner

2001-01-01

75

Solar cells  

Microsoft Academic Search

Solar cells are based on the photovoltaic effect of converting solar energy into electric energy. The mechanism for solar cells is divided into steps, that is, electron-hole pair generation by absorption of light in semiconductors, separation of electron-hole pairs by built-in potential, electron-hole recombination, collection of charge carriers by metal electrodes, etc. In this article, the principle and the theories

Hiroshi Tsubomura; Hikaru Kobayashi

1993-01-01

76

Efficient and ultraviolet durable inverted organic solar cells based on an aluminum-doped zinc oxide transparent cathode  

NASA Astrophysics Data System (ADS)

High performance inverted bulk heterojunction organic solar cells (OSCs), based on the blend of poly[[4,8-bis[(2-ethylhexyl)oxy] benzo [1,2-b:4,5-b'] dithiophene-2,6-diyl][3-fluoro-2-[(2-ethylhexyl)carbonyl]thieno[3,4-b]thiophenediyl

Liu, Hanxiao; Wu, Zhenghui; Hu, Jianqiao; Song, Qunliang; Wu, Bo; Lam Tam, Hoi; Yang, Qingyi; Hong Choi, Wing; Zhu, Furong

2013-07-01

77

Chemical Bath Deposited Zinc Sulfide Buffer Layers for Copper Indium Gallium Sulfur-selenide Solar Cells and Device Analysis  

SciTech Connect

Cd free CIGSS thin film solar cell structures with a MgF2/TCO/CGD-ZnS/CIGSS/Mo/SLG structure have been fabricated using chemical bath deposited (CBD)-ZnS buffer layers and high quality CIGSS absorber layers supplied from Shell Solar Industries. The use of CBD-ZnS, which is a higher band gap materials than CdS, improved the quantum efficiency of fabricated cells at lower wavelengths, leading to an increase in short circuit current. The best cell to date yielded an active area (0.43 cm2) efficiency of 13.3%. This paper also presents a discussion of the issues relating to the use of the CBD-ZnS buffer materials for improving device performance.

Kundu, Sambhu N.; Olsen, Larry C.

2005-01-03

78

Effect of textured tin oxide and zinc oxide substrates on the current generation in amorphous silicon solar cells  

Microsoft Academic Search

The authors evaluate material properties of a number of textured SnO2 and ZnO substrates and their effect on current generation in a-Si. Most of these TCOs have been used by others for a-Si solar cell research or module fabrication. Bulk optoelectronic and structural properties are reported for seven TCO films with haze from 1 to 14%. Their results show that

S. Hegedus; W. Buchanan; X. Liu; R. Gordon

1996-01-01

79

Process optimization of Al-doped zinc oxide films as a window layer for Cu(In,Ga)Se2 thin film solar cells  

NASA Astrophysics Data System (ADS)

Al-doped zinc oxide (AZO) thin film was deposited by an in-line pulsed-DC magnetron sputtering system for Cu(In, Ga)Se2 (CIGS) solar cell and optimum process conditions were analyzed. Of several process parameters, oxygen ratio to argon gas in the sputtering ambient was intensively investigated. As increasing the oxygen concentration from 0% to 2%, carrier concentration decreased from 4.8 × 1020 to 9.7 × 1017 cm-3 and Hall mobility reduced from 6.1 to 1.1 cm2/Vs. Resultantly, the resistivity of the AZO film increased significantly from 2.2 × 10-3 up to 5.9 × 10-1 ? cm as increasing the oxygen concentration. This was due to the effect of the scattering mechanism depending on the role of the oxygen in the AZO film. The average transmittance in the range of visible light was lowest as about 74% in the film deposited without oxygen. By the way, the optical band gap was obtained with the most large value of 3.6 eV in the film deposited without oxygen. For examining the feasibility as a window layer, the optimal AZO film deposited without oxygen was applied for making the CIGS solar cell. In this CIGS solar cell, the absorber layer was formed by using the rapid thermal annealing method of CuGa/In metal precursors. The cell was satisfactorily operated with the efficiency of 7.69% even though the cell was not optimized for the buffer layer and the composition of the absorber, and had no metal grids and anti-reflection layer.

Li, Zhao-Hui; Kwon, Sang Jik

2013-11-01

80

Aluminium phosphide-induced leukopenia.  

PubMed

Acute intoxication from the pesticide aluminium phosphide is a relatively rare, life-threatening condition in which cardiovascular decompensation is the most feared problem. We report the case of a patient exposed to aluminium phosphide-liberated phosphine gas. It resulted in the development of a gastroenteritis-like syndrome accompanied by severe reduction in white blood cell numbers as an early and prominent manifestation. By affecting important physiological processes such as mitochondrial function and reactive oxygen species homeostasis, phosphine could cause severe toxicity. After presenting the characteristics of certain leucocyte subpopulations we provide the current molecular understanding of the observed leukopenia which in part seems paradoxical. PMID:24172776

Ntelios, Dimitrios; Mandros, Charalampos; Potolidis, Evangelos; Fanourgiakis, Panagiotis

2013-10-30

81

Characterization testing of dual junction GaInP2\\/GaAs\\/Ge solar cell assemblies  

Microsoft Academic Search

The first commercial communications satellite with dual junction solar arrays was launched in August of 1997. The satellite is an HS 601HP series spacecraft built by Hughes Space and Communications Company (HSC). The solar cell assemblies consist of large area gallium-indium-phosphide on gallium-arsenide on germanium (GaInP2 \\/GaAs\\/Ge) solar cells with active GaInP2 and GaAs junctions. The cells were developed by

Michael R. Brown; Leland J. Goldhammer; George S. Goodelle; Charlene U. Lortz; John N. Perron; Joseph S. Powe; Joel A. Schwartz; B. Terence Cavicchi; Mark S. Gillanders; Dmitri D. Krut

1997-01-01

82

Low temperature electrodeposition of zinc oxide layers as transparent conducting oxide window layers for CIGS solar cells  

Microsoft Academic Search

Electrodeposition of zinc oxide layers has been carried out in simple aqueous solutions at 80°C in presence of zinc ions and dissolved oxygen. Extrinsic n type doping has been proven to be effective by anionic substitution of oxygen by chlorine, using chloride containing electrolytes. Doping level upper values up to 9.1019 cm-3 have been obtained, associated with lateral resistivies in

Jean ROUSSET; Daniel LINCOT

2009-01-01

83

Novel zinc porphyrin sensitizers for dye-sensitized solar cells: Synthesis and spectral, electrochemical, and photovoltaic properties  

NASA Astrophysics Data System (ADS)

Two donor-?-spacer-acceptor porphyrin dyes were synthesized for use in dye-sensitized solar cells. The dyes comprised the same donor (porphyrin derivative) consisting of 3,4,5-trimethoxybenzaldehyde and acceptor/anchoring group (carboxyl group) but varying ?-spacer consisting of a Schiff base structure. Each of the dyes displayed different adsorption behavior and coverage on the TiO2 surface. The porphyrin dyes PZnBIACOOH studied in this work exhibit red-shifted and broadened electronic spectra respect to the reference PZnCOOH as expected. By the introduction of Schiff base unit at the meso positions, the energy level of Eox (excited-state oxidation potentials) is significantly shifted to the positive compared with the reference PZnCOOH, indicating a decreased HOMO-LUMO gap. The highest power conversion efficiency of the two dyes based on DSSCs reached 1.75% under AM 1.5 G irradiation.

Tan, Qinglong; Zhang, Xuejun; Mao, Lijun; Xin, Guanqiong; Zhang, Shuanfen

2013-03-01

84

Solar Cells and Solar Panels.  

National Technical Information Service (NTIS)

The bibliography is a selection of unclassified and unlimited distribution references on Solar Cells and Solar Panels. These citations of reports present information on performance characteristics, fabrication, development of power levels, degradation stu...

1973-01-01

85

High rate direct current magnetron sputtered and texture-etched zinc oxide films for silicon thin film solar cells  

Microsoft Academic Search

Aluminum-doped zinc oxide (AZO) films were prepared by in-line direct current (dc) magnetron sputtering on glass substrates. Four types of ceramic targets with 0.5 wt.% or 1 wt.% of aluminum oxide and different preparation methods, namely normal sintered, soft sintered and hot pressed, were employed. The influence of different target manufacturing processes, aluminum concentration and sputtering conditions on AZO films were investigated.

T. Tohsophon; J. Hupkes; H. Siekmann; B. Rech; M. Schultheis; N. Sirikulrat

2008-01-01

86

Zinc, alpha cells and glucagon secretion.  

PubMed

Zinc concentrates in islet cells and is related to insulin secretion. Islet cells act as a unit within islets and hormone secretion in the islets is profoundly influenced by paracrine and autocrine regulation. Zinc has been recognised as a candidate paracrine inhibitor of glucagon secretion in alpha-cells. Further zinc fluxes may contribute to regulation of cell mass, Zn2+ may be cytotoxic and Zn2+ depletion by itself can cause cell death induced by oxidative stress. Recently, both free zinc ions and a number of zinc transporters have been localized in alpha-cells. These include zinc importers, ZIP1, ZIP10, and ZIP14 of the SLC39A family and zinc exporters, ZnT1, and ZnT4-8 of the SLC30A family. Furthermore, the redox state of thiol groups and Voltage Gated Ca2+ Channels (VGCC) add to the maintenance of a tight cytoplasmatic zinc homeostasis in the alpha-cells. The ZnT8 protein has emerged as particularly interesting since this zinc transporter has been identified as a genetic risk factor for the development of both type 1 and type 2 diabetes in which both alpha- and beta-cell functions are affected. Recent data discussed here suggest specific effects of Zn2+ on glucagon secretion and other alpha-cell functions. PMID:20034370

Egefjord, Laerke; Petersen, Andreas B; Rungby, Jørgen

2010-01-01

87

Nanowire-based All Oxide Solar Cells  

SciTech Connect

We present an all-oxide solar cell fabricated from vertically oriented zinc oxide nanowires and cuprous oxide nanoparticles. Our solar cell consists of vertically oriented n-type zinc oxide nanowires, surrounded by a film constructed from p-type cuprous oxide nanoparticles. Our solution-based synthesis of inexpensive and environmentally benign oxide materials in a solar cell would allow for the facile production of large-scale photovoltaic devices. We found that the solar cell performance is enhanced with the addition of an intermediate oxide insulating layer between the nanowires and the nanoparticles. This observation of the important dependence of the shunt resistance on the photovoltaic performance is widely applicable to any nanowire solar cell constructed with the nanowire array in direct contact with one electrode.

Yang*, Benjamin D. Yuhas and Peidong; Yang, Peidong

2008-12-07

88

Tapered aluminum-doped vertical zinc oxide nanorod arrays as light coupling layer for solar energy applications  

Microsoft Academic Search

Tapered aluminum-doped vertical zinc oxide nanorod arrays have been prepared by using simple electrodeposition at 75°C from an aqueous solution of zinc nitrate and aluminum nitrate. Two substrates were used, i.e., copper indium gallium (di)selenide solar cells and a solar thermal absorber. The resulting nanorod arrays were of high optical quality, indicting their applicability as a light coupling layer via

Jie Chen; Hong Ye; Lorenz Aé; Yang Tang; David Kieven; Thorsten Rissom; Julia Neuendorf; Martha Ch. Lux-Steiner

2011-01-01

89

Anodic Oxidation of Zinc Phosphide  

Microsoft Academic Search

Initial stages of a native oxidation on Zn3P2 by anodization have been investigated for the first time using 3% tartaric acid\\/propylene glycol electrolyte. A constant-current anodization is found to be superior to a constant-voltage anodization because of the rapid growth of the initial stage in the constant-voltage mode in view of controlling thin oxide layers. The surface composition of anodized

Toshikazu Suda; Yoshitada Murata; Shoichi Kurita

1986-01-01

90

Anodic Oxidation of Zinc Phosphide  

NASA Astrophysics Data System (ADS)

Initial stages of a native oxidation on Zn3P2 by anodization have been investigated for the first time using 3% tartaric acid/propylene glycol electrolyte. A constant-current anodization is found to be superior to a constant-voltage anodization because of the rapid growth of the initial stage in the constant-voltage mode in view of controlling thin oxide layers. The surface composition of anodized Zn3P2 was examined by AES and XPS. The oxide layer was identified as a mixture of ZnO, P2O5, and P2O3: the increased [P2O5+P2O3]/[ZnO] ratio of ˜ 1.3 was obtained at acidic and basic pH values, whereas the composition ratio was ˜ 0.2 near a neutral pH value as a result of selective dissolution of either ZnO or POx.

Suda, Toshikazu; Murata, Yoshitada; Kurita, Shoichi

1986-02-01

91

The production of zinc by thermal dissociation of zinc oxide—solar chemical reactor design  

Microsoft Academic Search

We describe the design, fabrication, and preliminary test of a novel solar chemical reactor for conducting the thermal dissociation of ZnO into zinc and oxygen at above 2000 K. The reactor configuration features a windowed rotating cavity-receiver lined with ZnO particles that are held by centrifugal force. With this arrangement, ZnO is directly exposed to high-flux solar irradiation and serves

P. Haueter; S. Moeller; R. Palumbo; A. Steinfeld

1999-01-01

92

Gallium phosphide nanowires as a substrate for cultured neurons.  

PubMed

Dissociated sensory neurons were cultured on epitaxial gallium phosphide (GaP) nanowires grown vertically from a gallium phosphide surface. Substrates covered by 2.5 microm long, 50 nm wide nanowires supported cell adhesion and axonal outgrowth. Cell survival was better on nanowire substrates than on planar control substrates. The cells interacted closely with the nanostructures, and cells penetrated by hundreds of wires were observed as well as wire bending due to forces exerted by the cells. PMID:17880143

Hällström, Waldemar; Mårtensson, Thomas; Prinz, Christelle; Gustavsson, Per; Montelius, Lars; Samuelson, Lars; Kanje, Martin

2007-09-19

93

Solar Cell Radiation Handbook.  

National Technical Information Service (NTIS)

The handbook to predict the degradation of solar cell electrical performance in any given space radiation environment is presented. Solar cell theory, cell manufacturing and how they are modeled mathematically are described. The interaction of energetic c...

B. E. Anspaugh H. Y. Tada J. R. Carter R. G. Downing

1982-01-01

94

The current distribution and shape change of zinc electrodes in secondary silver-zinc cells  

Microsoft Academic Search

The current and potential distributions of zinc electrodes in secondary zinc-silver oxide cells during cycling were studied using a sectioned electrode technique. The shape change occurring in zinc electrodes resulting from cell cycling was examined. The zinc electrodes used for this study were of a conventional type of design and were fabricated by a slurry paste method. The positive electrodes

S.-P. Poa; C. H. Wu

1978-01-01

95

Solar Cell Radiation Handbook.  

National Technical Information Service (NTIS)

A method is presented for predicting the degradation of a solar array in a space radiation environment. Solar cell technology which emphasizes the cell parameters that degrade in a radiation environment, is discussed along with the experimental techniques...

J. R. Carter H. Y. Tada

1973-01-01

96

Flexible Solar Cells.  

National Technical Information Service (NTIS)

Solar cell 'modules' are plastic strips coated with thin films of photovoltaic silicon that collect solar energy for instant conversion into electricity. Lasers divide the thin film coating into smaller cells to build up voltage. Developed by Iowa Thin Fi...

1994-01-01

97

Zinc-bromine cell design  

SciTech Connect

A set of slides is reproduced which illustrates the design of a zinc-bromine circulating battery. Low-cost manufacturing techniques and scale-up rationale are outlined, and design parameters are listed. Also outlined is a computer model of the zinc-bromine battery. (LEW)

Bellows, R.

1983-11-30

98

Zinc-bromine cell design  

NASA Astrophysics Data System (ADS)

A set of slides is reproduced which illustrates the design of a zinc-bromine circulating battery. Low cost manufacturing techniques and scale up rationale are outlined, and design parameters are listed. A computer model of the zinc-bromine battery is outlined.

Bellows, R.

1983-11-01

99

Zinc-bromine cell design  

Microsoft Academic Search

A set of slides is reproduced which illustrates the design of a zinc-bromine circulating battery. Low cost manufacturing techniques and scale up rationale are outlined, and design parameters are listed. A computer model of the zinc-bromine battery is outlined.

R. Bellows

1983-01-01

100

Solar Photovoltaic Cells.  

ERIC Educational Resources Information Center

|Reviews information on solar radiation as an energy source. Discusses these topics: the key photovoltaic material; the bank theory of solids; conductors, semiconductors, and insulators; impurity semiconductors; solid-state photovoltaic cell operation; limitations on solar cell efficiency; silicon solar cells; cadmium sulfide/copper (I) sulfide…

Mickey, Charles D.

1981-01-01

101

Temperature-stable and optically transparent thin-film zinc oxide aerogel electrodes as model systems for 3D interpenetrating organic-inorganic heterojunction solar cells.  

PubMed

Novel, nanostructured electrode materials comprising porous ZnO films with aerogel morphology are presented. Almost any substrate including polymers, metals, or ceramics can be coated using a method that is suitable for mass production. The thin, porous films can be prepared from the wet gels via conventional drying, supercritical drying is not necessary. The filigree ZnO network is thermally very stable and exhibits sufficient electrical conductivity for advanced electronic applications. The latter was tested by realizing a highly desired architecture of organic-inorganic hybrid solar cells. After sensitizing of the ZnO with a purely organic squarine dye (SQ2), a nanostructured, interpenetrating 3D network of the inorganic semiconductor (ZnO) and organic semiconductor (P3HT) was prepared. The solar cell device was tested under illumination with AM 1.5G solar light (100 mW/cm(2)) and exhibited an energy conversion efficiency (?(eff)) of 0.69%. PMID:23194020

Krumm, Michael; Pawlitzek, Fabian; Weickert, Jonas; Schmidt-Mende, Lukas; Polarz, Sebastian

2012-12-07

102

Effects of exogenous zinc on the cellular zinc distribution and cell cycle of A549 cells.  

PubMed

As the second most abundant transition metal in humans, zinc plays essential roles in normal cellular biological functions, including metabolism, signalling, proliferation, gene expression and apoptosis. We use ZnSO(4) as a stressor in this study to investigate for the first time the effects of exogenous Zn(2+) on both the cellular distribution of zinc and zinc-related proteins and the cell cycle of human lung adenocarcinoma (A549) cells. The cellular distribution of zinc and soluble proteins was determined in the whole cell as well as in the cytoplasmic and nuclear fractions. Exogenous zinc in the tested exposure range (0-100 µM) resulted in an altered cellular distribution of both zinc and the soluble proteins, together with total glutathione (GSx), the ratio of glutathione (GSH) to glutathione disulfide (GSSG) and non-protein sulphydryl (NPSH). Surprisingly, a turning point was observed in the re-distribution trend at a concentration of approximately 50 µM ZnSO(4). It is concluded that there exists a regulatory system in A549 cells that maintains the cellular zinc content stable in the presence of a certain range of extracellular zinc concentration. In addition, an MTT assay and flow cytometric analysis showed that the ZnSO(4) treatment led to a bi-phasic variation in viability and a slight fluctuation in the apoptosis of A549 cells. Our results will help to further elucidate zinc-related cell biology and biochemistry. PMID:23132559

Yuan, Na; Wang, Yan-Hong; Li, Ke-Jin; Zhao, Yue; Hu, Xin; Mao, Li; Zhao, Wen-Jie; Lian, Hong-Zhen; Zheng, Wei-Juan

2012-11-07

103

Zinc Deficiency and Microtubule Function in Prostate Cells.  

National Technical Information Service (NTIS)

Zinc deficiency is surprisingly common in the US. One organ expected to suffer during zinc deficiency is the prostate, since it is the greatest tissue accumulator of zinc in men. Zinc uptake in prostate epithelial cells is higher than most other cells typ...

B. N. Ames

2006-01-01

104

High energy density zinc-air cells for portable electronics  

Microsoft Academic Search

A basic overview of zinc-air technology, performance features, electrochemistry, and ACTIVAIR cell construction and unique cell selection criteria is presented. A cell selection example is provided and major zinc-air applications are highlighted. 10 refs.

S. F. Bender; D. W. Biegger

1980-01-01

105

Gallium Phosphide Photodiode Development.  

National Technical Information Service (NTIS)

The specific objectives of this program were to fabricate, test and deliver five single-element (detector size 0.01 x 0.01 inch) gallium phosphide (GaP) photovoltaic detectors with performance design goals (for each element) of eta > 30% and NEP < or = 2....

A. M. Chiang R. Rotolante

1977-01-01

106

Thin boron phosphide coating as a corrosion-resistant layer  

DOEpatents

A surface prone to corrosion in corrosive environments is rendered anticorrosive by CVD growing a thin continuous film, e.g., having no detectable pinholes, thereon, of boron phosphide. In one embodiment, the film is semiconductive. In another aspect, the invention is an improved photoanode, and/or photoelectrochemical cell with a photoanode having a thin film of boron phosphide thereon rendering it anticorrosive, and providing it with unexpectedly improved photoresponsive properties.

Not Available

1982-08-25

107

Study on the Realization of Zinc Point and the Zinc-Point Cell Comparison  

Microsoft Academic Search

Continuing our study on aluminum, tin, and silver points, a study on the realization of the zinc point was conducted. Zinc-point\\u000a cells were newly fabricated using 6N-nominal grade zinc samples, impurity elements of which were analyzed extensively based\\u000a on glow-discharge mass spectrometry (GDMS). The present paper reports the temperature measurements done using the newly fabricated\\u000a cells during the zinc freezing

J. V. Widiatmo; M. Sakai; K. Satou; K. Yamazawa; J. Tamba; M. Arai

2011-01-01

108

Reaction in the silver zinc cell  

Microsoft Academic Search

An adiabatic calorimeter was used to measure the thermodynamics of the silver zinc cell. The charge and discharge reactions were shown to take place in two stages involving the production of argentous oxide and argentic oxide respectively. No thermal evidence was found to suggest the existence of a higher oxide of silver. The cell reactions were

M. I. Gillibrand; L. Langrish; G. R. Lomax

1971-01-01

109

Solar cell encapsulation  

SciTech Connect

A polymer syrup for encapsulating solar cell assemblies. The syrup includes uncrosslinked poly(n-butyl)acrylate dissolved in n-butyl acrylate monomer. Preparation of the poly(n-butyl)acrylate and preparation of the polymer syrup is disclosed. Methods for applying the polymer syrup to solar cell assemblies as an encapsulating pottant are described. Also included is a method for solar cell construction utilizing the polymer syrup as a dual purpose adhesive and encapsulating material.

Gupta, A.; Ingham, J.D.; Yavrouian, A.H.

1983-05-10

110

Nanocrystal solar cells  

Microsoft Academic Search

This dissertation presents the results of a research agenda aimed at improving integration and stability in nanocrystal-based solar cells through advances in active materials and device architectures. The introduction of 3-dimensional nanocrystals illustrates the potential for improving transport and percolation in hybrid solar cells and enables novel fabrication methods for optimizing integration in these systems. Fabricating cells by sequential deposition

Ilan Gur; Ilan

2006-01-01

111

Solar Cells and Solar Panels. Volume I.  

National Technical Information Service (NTIS)

An annotated bibliography is provided of documents in which performance characteristics of various solar cells, particularly types containing gallium arsenides, silicon, or cadmium sulfides, are evaluated. Other reports include solar-cell fabrication, dev...

1970-01-01

112

Twinning superlattices in indium phosphide nanowires.  

PubMed

Semiconducting nanowires offer the possibility of nearly unlimited complex bottom-up design, which allows for new device concepts. However, essential parameters that determine the electronic quality of the wires, and which have not been controlled yet for the III-V compound semiconductors, are the wire crystal structure and the stacking fault density. In addition, a significant feature would be to have a constant spacing between rotational twins in the wires such that a twinning superlattice is formed, as this is predicted to induce a direct bandgap in normally indirect bandgap semiconductors, such as silicon and gallium phosphide. Optically active versions of these technologically relevant semiconductors could have a significant impact on the electronics and optics industry. Here we show first that we can control the crystal structure of indium phosphide (InP) nanowires by using impurity dopants. We have found that zinc decreases the activation barrier for two-dimensional nucleation growth of zinc-blende InP and therefore promotes crystallization of the InP nanowires in the zinc-blende, instead of the commonly found wurtzite, crystal structure. More importantly, we then demonstrate that we can, once we have enforced the zinc-blende crystal structure, induce twinning superlattices with long-range order in InP nanowires. We can tune the spacing of the superlattices by changing the wire diameter and the zinc concentration, and we present a model based on the distortion of the catalyst droplet in response to the evolution of the cross-sectional shape of the nanowires to quantitatively explain the formation of the periodic twinning. PMID:19020617

Algra, Rienk E; Verheijen, Marcel A; Borgström, Magnus T; Feiner, Lou-Fé; Immink, George; van Enckevort, Willem J P; Vlieg, Elias; Bakkers, Erik P A M

2008-11-20

113

Ingestion of gallium phosphide nanowires has no adverse effect on Drosophila tissue function.  

PubMed

Engineered nanoparticles have been under increasing scrutiny in recent years. High aspect ratio nanoparticles such as carbon nanotubes and nanowires have raised safety concerns due to their geometrical similarity to asbestos fibers. III-V epitaxial semiconductor nanowires are expected to be utilized in devices such as LEDs and solar cells and will thus be available to the public. In addition, clean-room staff fabricating and characterizing the nanowires are at risk of exposure, emphasizing the importance of investigating their possible toxicity. Here we investigated the effects of gallium phosphide nanowires on the fruit fly Drosophila melanogaster. Drosophila larvae and/or adults were exposed to gallium phosphide nanowires by ingestion with food. The toxicity and tissue interaction of the nanowires was evaluated by investigating tissue distribution, activation of immune response, genome-wide gene expression, life span, fecundity and somatic mutation rates. Our results show that gallium phosphide nanowires applied through the diet are not taken up into Drosophila tissues, do not elicit a measurable immune response or changes in genome-wide gene expression and do not significantly affect life span or somatic mutation rate. PMID:23787695

Adolfsson, Karl; Schneider, Martina; Hammarin, Greger; Häcker, Udo; Prinz, Christelle N

2013-06-20

114

Porphyrin-sensitized solar cells.  

PubMed

Nature has chosen chlorophylls in plants as antennae to harvest light for the conversion of solar energy in complicated photosynthetic processes. Inspired by natural photosynthesis, scientists utilized artificial chlorophylls - the porphyrins - as efficient centres to harvest light for solar cells sensitized with a porphyrin (PSSC). After the first example appeared in 1993 of a porphyrin of type copper chlorophyll as a photosensitizer for PSSC that achieved a power conversion efficiency of 2.6%, no significant advance of PSSC was reported until 2005; beta-linked zinc porphyrins were then reported to show promising device performances with a benchmark efficiency of 7.1% reported in 2007. Meso-linked zinc porphyrin sensitizers in the first series with a push-pull framework appeared in 2009; the best cell performed comparably to that of a N3-based device, and a benchmark 11% was reported for a porphyrin sensitizer of this type in 2010. With a structural design involving long alkoxyl chains to envelop the porphyrin core to suppress the dye aggregation for a push-pull zinc porphyrin, the PSSC achieved a record 12.3% in 2011 with co-sensitization of an organic dye and a cobalt-based electrolyte. The best PSSC system exhibited a panchromatic feature for light harvesting covering the visible spectral region to 700 nm, giving opportunities to many other porphyrins, such as fused and dimeric porphyrins, with near-infrared absorption spectral features, together with the approach of molecular co-sensitization, to enhance the device performance of PSSC. According to this historical trend for the development of prospective porphyrin sensitizers used in PSSC, we review systematically the progress of porphyrins of varied kinds, and their derivatives, applied in PSSC with a focus on reports during 2007-2012 from the point of view of molecular design correlated with photovoltaic performance. PMID:23023240

Li, Lu-Lin; Diau, Eric Wei-Guang

2012-10-01

115

Zinc air fuel cell for industrial and specialty vehicles  

Microsoft Academic Search

Metallic Power has demonstrated a regenerative zinc air fuel cell for applications in industrial and specialty vehicles. The fuel cell uses zinc pellets and atmospheric oxygen to generate electric current; the reaction product is zinc oxide, which is collected in a tank. In its present stage of development the 36 V fuel cell will deliver approximately 6 kWh, with a

S. Smedley

2000-01-01

116

High efficiency cadmium telluride and zinc telluride based thin-film solar cells. Annual subcontract report, 1 March 1990--28 February 1992  

SciTech Connect

This report describes work to improve the basic understanding of CdTe and ZnTe alloys by growing and characterizing these films along with cell fabrication. The major objective was to develop wide-band-gap (1.6--1.8 eV) material for the top cell, along with compatible window material and transparent ohmic contacts, so that a cascade cell design can be optimized. Front-wall solar cells were fabricated with a glass/SnO{sub 2}/CdS window, where the CdS film is thin to maximize transmission and current. Wide-band-gap absorber films (E{sub g} = 1.75 eV) were grown by molecular beam epitaxy (MBE) and metal-organic chemical vapor deposition (MOCVD) techniques, which provided excellent control for tailoring the film composition and properties. CdZnTe films were grown by both MBE and MOCVD. All the as-grown films were characterized by several techniques (surface photovoltage spectroscopy, Auger electron spectroscopy (AES), and x-ray photoelectron spectroscopy (XPS)) for composition, bulk uniformity, thickness, and film and interface quality. Front-wall-type solar cells were fabricated in collaboration with Ametek Materials Research Laboratory using CdTe and CdZnTe polycrystalline absorber films. The effects of processing on ternary film were studied by AES and XPS coupled with capacitance voltage and current voltage measurements as a function of temperature. Bias-dependent spectral response and electrical measurements were used to test some models in order to identify and quantify dominant loss mechanisms.

Rohatgi, A.; Sudharsanan, R.; Ringel, S.A.; Chou, H.C. [Georgia Inst. of Tech., Atlanta, GA (United States)

1992-10-01

117

Zinc-doping in TiO2 films to enhance electron transport in dye-sensitized solar cells under low-intensity illumination.  

PubMed

A nanocrystalline TiO(2) film with highly dispersed Zn-doping shows its capability for efficient electron transport in dye-sensitized solar cells (DSSCs). The Zn-doping is conducted via Zn(2+) introduction into a layered titanate followed by hydrothermal treatment and calcination. The Zn-doped films exhibit an elevated electron Fermi level, which may enhance band bending to lower the density of empty trap states. Because of this Zn-doping, the consequent DSSCs can alleviate the decay of light-to-electric energy conversion efficiency due to light intensity reduction. Intensity-modulated spectroscopic analysis reveals that enhanced transport of photogenerated electrons as a result of the trap density minimization is responsible for the high cell performance under low-intensity illumination. A Zn-doping content of ca. 0.4 at% Zn/Ti can enhance the light conversion efficiency by 23% at a solar light intensity as low as 11 mW cm(-2). This technique can significantly extend the indoor application of DSSCs. PMID:19830333

Wang, Kai-Ping; Teng, Hsisheng

2009-08-18

118

3. Right side of Zinc Plant, from Cell Room midpoint ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

3. Right side of Zinc Plant, from Cell Room midpoint to Plant Office (foreground) and #5 Roaster and Concentrate Handling (background). View is to the east. - Sullivan Electrolytic Zinc Plant, Government Gulch, Kellogg, Shoshone County, ID

119

Systems analysis of Mars solar electric propulsion vehicles  

Microsoft Academic Search

Mission performance, mass, initial power, and cost are determined for solar electric propulsion vehicles across a range of payload masses, reference powers, and mission trajectories. Thick radiation shielding is added to arrays using indium phosphide or III-V multijunction solar cells to reduce the damage incurred through the radiation belts. Special assessments of power management and distribution systems, atmospheric drag, and

J. M. Hickman; H. B. Curtis; B. H. Kenny; R. J. Sefcik

1990-01-01

120

Investigation of surface phase formation during tin-rich growth of Copper2ZincTinSulfer4 polycrystlalline thin films for solar cells  

NASA Astrophysics Data System (ADS)

Cu2ZnSnS4 (CZTS) is a semiconductor material made of nontoxic, earth abundant elements, making it a promising topic of research for absorber layers in thin film solar cells. We observed that rapid thermal annealing of tin (Sn)-rich co-sputtered CZTS films resulted in crystalline, hexagonal platelets of tin-disulfide (SnS2) 5-30 µm long at the surface of the film. In this work, the formation mechanisms of these surface crystallites and their implications for CZTS absorber layer processing were investigated. The formation and decomposition of these platelets were studied by observing the changes in their structural, morphological, compositional, and vibrational properties accompanying the imposition of lateral temperature gradients as well as different annealing atmospheres. The homogeneous co-sputtered films were annealed in a graphite boat in a quartz reactor using a base heater and halogen lamp. Interrupting annealings to examine stages of crystal formation showed at around 400 °C SnS2 began to form on the surface of films. Near the edges of the film, where temperatures were found to be higher, crystals melted into an amorphous unknown tin-sulfide phase. Diffusion of species from the film into the base of the crystals formed long CZTS grains of which the amorphous phase left behind as it coalesced. Annealing without sulfur (S) increased Sn and S losses from the film and increased the number of crystals nucleated on the surface of the film. For solar cell device applications of CZTS thin films, removal of these SnS2 surface crystallites is necessary; thus wet chemical and thermal decomposition etching techniques were studied. Wet etching attempts with KCN and NH4OH solutions did little to etch crystals. HCl solution damaged the CZTS film as much as the crystals and therefore was also unsuitable. Thermal etching by evacuating the chamber near the end of annealing transformed the SnS2 crystals into a grainy, S-poor Sn phase via the decomposition of SnS2 by removing the vapor species with which it is in equilibrium. Understanding the role of Sn species during annealing is important for the complex CZTS system because small deviations from Sn stoichiometry results in drastic changes in the secondary phases and microstructure of the film. The experiments and insight provided in this thesis represent unexplored unconventional methods toward CZTS growth and different approaches for CZTS processing for development of thin film solar cell technology.

Bolke, Joseph Glenn

121

Colloidal nanocrystal solar cells  

Microsoft Academic Search

.  Colloidal nanocrystal based organic solar cells are envisaged to be a cost effective alternative to conventional inorganic\\u000a cells. A variety of studies have been reported recently with the goal to increases energy conversion efficiencies, which must\\u000a be pushed towards 10% for devices to be practical. We review the status of this work, critically examining the factors affecting\\u000a hybrid solar cell

Sandeep Kumar; Gregory D. Scholes

2008-01-01

122

Dye Sensitized Solar Cells  

PubMed Central

Dye sensitized solar cell (DSSC) is the only solar cell that can offer both the flexibility and transparency. Its efficiency is comparable to amorphous silicon solar cells but with a much lower cost. This review not only covers the fundamentals of DSSC but also the related cutting-edge research and its development for industrial applications. Most recent research topics on DSSC, for example, applications of nanostructured TiO2, ZnO electrodes, ionic liquid electrolytes, carbon nanotubes, graphene and solid state DSSC have all been included and discussed.

Wei, Di

2010-01-01

123

Solar cell power supply circuit  

SciTech Connect

A solar cell power supply circuit for use in a calculator or equipment is disclosed. It includes a solar cell or cells, a back-up capacitor connected to the solar cells, and a circuit element connected to be responsive whether the electromotive force from the solar cells lies within a range of operation for a load element of the solar cells, typically an LSI semiconductor device. The back-up capacitor starts charging when the electromotive force of the solar cells falls out of the range of operation for the load element. Preferably, an alarm sound is delivered when the electromotive force of the solar cells is poor.

Higuchi, M.

1984-02-28

124

Synthesis and optical properties of gallium phosphide nanotubes.  

PubMed

Gallium phosphide nanotubes with zinc blende structure were synthesized for the first time. The as-prepared GaP nanotubes are polycrystalline with diameters of 30-120 nm and occasionally partially filled. The growth has been reasonably proposed to follow vapor-liquid-solid (VLS) mechanism. The integration of the nanotubular structure with the unique intrinsic semiconducting properties of GaP might bring GaP nanotubes some novel optical and electronic properties and applications. PMID:16853550

Wu, Qiang; Hu, Zheng; Liu, Chun; Wang, Xizhang; Chen, Yi; Lu, Yinong

2005-10-27

125

ZINC  

Technology Transfer Automated Retrieval System (TEKTRAN)

Increasing interest by the public in components of the diet that promote health and well being prompt many questions about zinc. This mineral is a nutrient that plays key roles in regulating many biological functions ranging from cell development to brain function. Concern about the importance of zi...

126

Vertical Multijunction Solar Cells.  

National Technical Information Service (NTIS)

A theoretical analysis of the vertical multijunction (VMJ) solar cell was performed which indicated that using silicon certain configurations could be fabricated to satisfy the program objectives. Results indicate that initial AMO efficiencies of 15% can ...

P. M. Stella

1973-01-01

127

Solar cell array interconnects  

DOEpatents

Electrical interconnects are disclosed for solar cells or other electronic components using a silver-silicone paste or a lead-tin (Pb-Sn) no-clean fluxless solder cream, whereby the high breakage of thin (<6 mil thick) solar cells using conventional solder interconnect is eliminated. The interconnects of this invention employs copper strips which are secured to the solar cells by a silver-silicone conductive paste which can be used at room temperature, or by a Pb-Sn solder cream which eliminates undesired residue on the active surfaces of the solar cells. Electrical testing using the interconnects of this invention has shown that no degradation of the interconnects developed under high current testing, while providing a very low contact resistance value. 4 figs.

Carey, P.G.; Thompson, J.B.; Colella, N.J.; Williams, K.A.

1995-11-14

128

Silicon for Solar Cells.  

National Technical Information Service (NTIS)

This report is an introduction to silicon solar cell technology and photovoltaic device operation. The conventional semiconductor industry techniques for extraction of Si from quartz, purification of silanes, chemical vapor deposition of polycrystalline s...

T. F. Ciszek

1984-01-01

129

Thin silicon solar cells  

SciTech Connect

The silicon-film design achieves high performance by using a dun silicon layer and incorporating light trapping. Optimally designed thin crystalline solar cells (<50 microns thick) have performance advantages over conventional thick devices. The high-performance silicon-film design employs a metallurgical barrier between the low-cost substrate and the thin silicon layer. Light trapping properties of silicon-film on ceramic solar cells are presented and analyzed. Recent advances in process development are described here.

Hall, R.B.; Bacon, C.; DiReda, V.; Ford, D.H.; Ingram, A.E.; Cotter, J.; Hughes-Lampros, T.; Rand, J.A.; Ruffins, T.R.; Barnett, A.M. [Astro Power Inc., Solar Park, Newark, DE (United States)

1992-12-01

130

Properties of double-layered Ga-doped Al-zinc-oxide/titanium-doped indium-tin-oxide thin films prepared by dc magnetron sputtering applied for Si-based thin film solar cells  

SciTech Connect

In this article, Ga-doped Al-zinc-oxide (GAZO)/titanium-doped indium-tin-oxide (ITIO) bi-layer films were deposited onto glass substrates by direct current (dc) magnetron sputtering. The bottom ITIO film, with a thickness of 200 nm, was sputtered onto the glass substrate. The ITIO film was post-annealed at 350 deg. C for 10-120 min as a seed layer. The effect of post-annealing conditions on the morphologies, electrical, and optical properties of ITIO films was investigated. A GAZO layer with a thickness of 1200 nm was continuously sputtered onto the ITIO bottom layer. The results show that the properties of the GAZO/ITIO films were strongly dependent on the post-annealed conditions. The spectral haze (T{sub diffuse}/T{sub total}) of the GAZO/ITIO bi-layer films increases upon increasing the post-annealing time. The haze and resistivity of the GAZO/ITIO bi-layer films were improved with the post-annealed process. After optimizing the deposition and annealing parameters, the GAZO/ITIO bi-layer film has an average transmittance of 83.20% at the 400-800 nm wavelengths, a maximum haze of 16%, and the lowest resistivity of 1.04 x 10{sup -3}{Omega} cm. Finally, the GAZO/ITIO bi-layer films, as a front electrode for silicon-based thin film solar cells, obtained a maximum efficiency of 7.10%. These encouraging experimental results have potential applications in GAZO/ITIO bi-layer film deposition by in-line sputtering without the wet-etching process and enable the production of highly efficient, low-cost thin film solar cells.

Wang, Chao-Chun; Wuu, Dong-Sing; Lin, Yang-Shih; Lien, Shui-Yang; Huang, Yung-Chuan; Liu, Chueh-Yang; Chen, Chia-Fu; Nautiyal, Asheesh; Lee, Shuo-Jen [Department of Materials Science and Engineering, National Chung Hsing University, Taichung 40227, Taiwan (China); Department of Materials Science and Engineering, MingDao University, Changhua 52345, Taiwan (China); Department of Mechanical Engineering, Yuan Ze University, Taoyuan 320, Taiwan (China)

2011-11-15

131

Nanocrystal Solar Cells  

SciTech Connect

This dissertation presents the results of a research agenda aimed at improving integration and stability in nanocrystal-based solar cells through advances in active materials and device architectures. The introduction of 3-dimensional nanocrystals illustrates the potential for improving transport and percolation in hybrid solar cells and enables novel fabrication methods for optimizing integration in these systems. Fabricating cells by sequential deposition allows for solution-based assembly of hybrid composites with controlled and well-characterized dispersion and electrode contact. Hyperbranched nanocrystals emerge as a nearly ideal building block for hybrid cells, allowing the controlled morphologies targeted by templated approaches to be achieved in an easily fabricated solution-cast device. In addition to offering practical benefits to device processing, these approaches offer fundamental insight into the operation of hybrid solar cells, shedding light on key phenomena such as the roles of electrode-contact and percolation behavior in these cells. Finally, all-inorganic nanocrystal solar cells are presented as a wholly new cell concept, illustrating that donor-acceptor charge transfer and directed carrier diffusion can be utilized in a system with no organic components, and that nanocrystals may act as building blocks for efficient, stable, and low-cost thin-film solar cells.

Gur, Ilan

2006-12-15

132

Zinc and Copper Status in Patients with Sickle Cell Anemia  

Microsoft Academic Search

Plasma zinc and copper concentrations were determined by atomic absorption spectroscopy in 57 patients with sickle cell anemia and in 45 control subjects from the Eastern Province of Saudi Arabia. Plasma zinc and copper levels in patients were found to be close to those of the control subjects. Similarly, there was a difference neither in urinary zinc level nor in

A. I. Alayash; A. Dafallah; A. A. Al-Quorain; A. H. S. Omer; M. T. Wilson

1987-01-01

133

Photoelectrochemical Solar Cells.  

ERIC Educational Resources Information Center

|This introduction to photoelectrochemical (PEC) cells reviews topics pertaining to solar energy conversion and demonstrates the ease with which a working PEC cell can be prepared with n-type silicon as the photoanode and a platinum counter electrode (both immersed in ethanolic ferrocene/ferricenium solutions). Experiments using the cell are…

McDevitt, John T.

1984-01-01

134

Parameterization of Solar Cells.  

National Technical Information Service (NTIS)

The aggregation (sorting) of the individual solar cells into an array is commonly based on a single operating point on the current-voltage (I-V) characteristic curve. An alternative approach for cell performance prediction and cell screening is provided b...

J. Appelbaum A. Chait D. Thompson

1992-01-01

135

Integrated solar cell array  

Microsoft Academic Search

An integrated array of solar cells, each cell having a positive and a negative electrode, is disclosed. A first grid comprising a plurality of non-intersecting electrically conductive members is affixed to an insulating substrate. Each single individual member of this grid forms the negative electrode of an individual cell of the array. Overlying and affixed to the negative electrodes and

W. J. Biter; F. A. Shirland

1980-01-01

136

High efficiency thin film cadmium telluride solar cells  

NASA Astrophysics Data System (ADS)

Cadmium sulfide (CdS), grown from an aqueous solution, and zinc oxide (ZnO), cadmium zinc sulfide (Cd1-xZnxS), and zinc selenide (ZnSe), deposited by metalorganic chemical vapor deposition (MOCVD), have been used as the window for thin film cadmium telluride (CdTe) solar cells. Thin film solar cells were prepared by the successive deposition of the window and p-CdTe (by MOCVD and close-spaced sublimation, CSS) on SnO2:F/glass substrates. CdS/CdTe(CSS) solar cells show considerably better characteristics than CdS/CdTe(MOCVD) solar cells because of the better microstructure of CSS CdTe films. Total area conversion efficiency of 14.6%, verified by the National Renewable Energy Laboratory, has been achieved for solar cells of about 1 cm2 area. Solar cell prepared by using ZnO, ZnSe, or Cd1-xZnxS as window have significantly lower photovoltage than CdS/CdTe solar cells.

Chu, T. L.; Chu, Shirley S.; Britt, J.; Chen, G.; Ferekides, C.; Schultz, N.; Wang, C.; Wu, C. Q.

1992-12-01

137

Sliver solar cells  

NASA Astrophysics Data System (ADS)

Sliver solar cells are thin, mono-crystalline silicon solar cells, fabricated using micro-machining techniques combined with standard solar cell fabrication technology. Sliver solar modules can be efficient, low cost, bifacial, transparent, flexible, shadow-tolerant, and lightweight. Sliver modules require only 5 to 10% of the pure silicon and less than 5% of the wafer starts per MWp of factory output when compared with conventional photovoltaic modules. At ANU, we have produced 20% efficient Sliver solar cells using a robust, optimised cell fabrication process described in this paper. We have devised a rapid, reliable and simple method for extracting Sliver cells from a Sliver wafer, and methods for assembling modularised Sliver cell sub-modules. The method for forming these Sliver sub-modules, along with a low-cost method for rapidly forming reliable electrical interconnections, are presented. Using the sub-module approach, we describe low-cost methods for assembling and encapsulating Sliver cells into a range of module designs.

Franklin, Evan; Blakers, Andrew; Everett, Vernie; Weber, Klaus

2007-12-01

138

Solar cell window fitting  

SciTech Connect

A window fitting is described comprising: (a) a frame structure dimensioned to fit in a window opening of a building; (b) a pair of transparent panes supported by the frame structure in substantially parallel disposition with respect to each other to define a space there between; a window blind secured to the frame structure so as to be disposed in the space between the transparent panes, the window blind comprising a plurality of slats mounted in generally parallel disposition with respect to each other for substantially simultaneous rotation of the slats so that each of the slats moves through an angular range from a CLOSED configuration in which the slats overlap each other so as to block passage of sunlight through the window opening to a fully OPEN configuration in which a maximum amount of sunlight can pass through the window opening; (d) a plurality of solar-chargeable batteries for storing electrical energy, the batteries being mounted on the slats; (e) a plurality of solar cells mounted on the batteries so as to be exposed to sunlight incident upon the slats, the batteries thereby being sandwiched between the solar cells and the slats, the solar cells being electrically connected to the batteries so that the batteries can be electrically charged by the solar cells; and means for removing from the batteries the stored electrical energy that has been generated by the solar cells.

Gillard, C.W.

1993-06-22

139

Large Retractable Solar Cell Array.  

National Technical Information Service (NTIS)

Presented are detailed drawings of the orientation mechanism in corporation of reference solar cell and solar cell modules of 8 and 12-mil cells in the solar panel design, detail drawings of the drum mechanism and solar array, and all electronic circuit d...

E. O. Felkel G. Wolff

1969-01-01

140

Study on the Realization of Zinc Point and the Zinc-Point Cell Comparison  

NASA Astrophysics Data System (ADS)

Continuing our study on aluminum, tin, and silver points, a study on the realization of the zinc point was conducted. Zinc-point cells were newly fabricated using 6N-nominal grade zinc samples, impurity elements of which were analyzed extensively based on glow-discharge mass spectrometry (GDMS). The present paper reports the temperature measurements done using the newly fabricated cells during the zinc freezing process, under which the zinc fixed point is defined, and the analysis of the freezing curve obtained. Comparisons of zinc-point temperatures realized by the newly fabricated cells (cell-to-cell comparisons) were also conducted. Zinc-point depression due to impurity elements was calculated based on the sum of individual estimates and the impurity element analysis. One of the cells evaluated was drawn out from its crucible and analyzed by GDMS at four points, namely, at around the center of the top, of the middle, of the bottom, and around the outer part of the middle area. The purpose of this cell disassembly is to see whether or not there has been some difference before and after cell fabrication, as well as difference in impurity element distribution within the ingot. From the aforementioned studies, some findings were obtained. First finding is that the homogeneity of the zinc ingot was within 30%, except for Pb, which was more concentrated in the center part. Second finding is that the cell-to-cell temperature difference changes along with the progressing solidification process. As a consequence, for an accurate cell-to-cell comparison, the locus in the freezing plateau where the comparison is done should be determined. Third finding is that the slope analysis estimates accurately the cell-to-cell comparison, and is consistent with the impurity analysis. This shows that the slope analysis gives extensive information about the effect of impurity to the zinc-point realization, especially after the cell fabrication.

Widiatmo, J. V.; Sakai, M.; Satou, K.; Yamazawa, K.; Tamba, J.; Arai, M.

2010-11-01

141

Study on the Realization of Zinc Point and the Zinc-Point Cell Comparison  

NASA Astrophysics Data System (ADS)

Continuing our study on aluminum, tin, and silver points, a study on the realization of the zinc point was conducted. Zinc-point cells were newly fabricated using 6N-nominal grade zinc samples, impurity elements of which were analyzed extensively based on glow-discharge mass spectrometry (GDMS). The present paper reports the temperature measurements done using the newly fabricated cells during the zinc freezing process, under which the zinc fixed point is defined, and the analysis of the freezing curve obtained. Comparisons of zinc-point temperatures realized by the newly fabricated cells (cell-to-cell comparisons) were also conducted. Zinc-point depression due to impurity elements was calculated based on the sum of individual estimates and the impurity element analysis. One of the cells evaluated was drawn out from its crucible and analyzed by GDMS at four points, namely, at around the center of the top, of the middle, of the bottom, and around the outer part of the middle area. The purpose of this cell disassembly is to see whether or not there has been some difference before and after cell fabrication, as well as difference in impurity element distribution within the ingot. From the aforementioned studies, some findings were obtained. First finding is that the homogeneity of the zinc ingot was within 30%, except for Pb, which was more concentrated in the center part. Second finding is that the cell-to-cell temperature difference changes along with the progressing solidification process. As a consequence, for an accurate cell-to-cell comparison, the locus in the freezing plateau where the comparison is done should be determined. Third finding is that the slope analysis estimates accurately the cell-to-cell comparison, and is consistent with the impurity analysis. This shows that the slope analysis gives extensive information about the effect of impurity to the zinc-point realization, especially after the cell fabrication.

Widiatmo, J. V.; Sakai, M.; Satou, K.; Yamazawa, K.; Tamba, J.; Arai, M.

2011-01-01

142

Photocatalytic degradation of phenol under solar radiation using microwave irradiated zinc oxide  

Microsoft Academic Search

The effect of preparation method on the photocatalytic degradation of phenol using zinc oxides under solar radiation was studied in batch reactors. Zinc oxide was prepared by different methods by varying precipitating agents and the source of precursors and microwave irradiation time and characterized by XRD, surface area, acid sites and crystallite sizes. The photocatalytic reactions were carried out by

K. M. Parida; S. Parija

2006-01-01

143

Zinc air refuelable battery: alternative zinc fuel morphologies and cell behavior  

SciTech Connect

Multicell zinc/air batteries have been tested previously in the laboratory and as part of the propulsion system of an electric bus; cut zinc wire was used as the anode material. This battery is refueled by a hydraulic transport of 0.5-1 mm zinc particles into hoppers above each cell. We report an investigation concerning alternative zinc fuel morphologies, and energy losses associated with refueling and with overnight or prolonged standby. Three types of fuel pellets were fabricated, tested and compared with results for cut wire: spheres produced in a fluidized bed electrolysis cell; elongated particles produced by gas-atomization; and pellets produced by chopping 1 mm porous plates made of compacted zinc fines. Relative sizes of the particles and cell gap dimensions are critical. All three types transported within the cell 1553 and showed acceptable discharge characteristics, but a fluidized bed approach appears especially attractive for owner/user recovery operations.

Cooper, J.F.; Krueger, R.

1997-01-01

144

Modeling of high efficiency solar cells under laser pulse for power beaming applications  

NASA Astrophysics Data System (ADS)

Solar cells have been used to convert sunlight to electrical energy for many years and also offer great potential for non-solar energy conversion applications. Their greatly improved performance under monochromatic light compared to sunlight, makes them suitable as photovoltaic (PV) receivers in laser power beaming applications. Laser beamed power to a PV array receiver could provide power to satellites, an orbital transfer vehicle, or a lunar base. Gallium arsenide (GaAs) and indium phosphide (InP) solar cells have calculated efficiencies of more than 50 percent under continuous illumination at the optimum wavelength. Currently high power free-electron lasers are being developed which operate in pulsed conditions. Understanding cell behavior under a laser pulse is important in the selection of the solar cell material and the laser. An experiment by NAsA lewis and JPL at the AVLIS laser facility in Livermore, CA presented experimental data on cell performance under pulsed laser illumination. Reference 5 contains an overview of technical issues concerning the use of solar cells for laser power conversion, written before the experiments were performed. As the experimental results showed, the actual effects of pulsed operation are more complicated. Reference 6 discusses simulations of the output of GaAs concentrator solar cells under pulsed laser illumination. The present paper continues this work, and compares the output of Si and GaAs solar cells.

Jain, Raj K.; Landis, Geoffrey A.

1994-09-01

145

Fabrication and testing of sealed silver-zinc cells  

Microsoft Academic Search

A number of Type HS40-7 sealed silver-zinc cells and experimental 40AH sealed silver-zinc cells were fabricated. Cells of each experimental group contained one variation from the standard configuration (HS40-7) cell. Cells from each of five experimental cell groups and cells of the standard configuration were tested to characterize voltage and capacity performance at various discharge rates. The test cells were

C. P. Donnel III

1976-01-01

146

Terrestrial solar spectra, solar simulation and solar cell efficiency measurement  

NASA Astrophysics Data System (ADS)

Fundamentals of light transmittance and, both measured and modeled atmospheric effects (i.e., air mass, molecular and aerosal scattering, and absorption) on terrestrial solar spectra are discussed. Geometric effects, such as global rather than direct beam measurements, and detector orientation are also reviewed. The SERI proposed ASTM global and direct beam terrestrial solar spectra are also presented. A detailed review/evaluation of the spectral characteristics of a number of solar simulators is given. Methods of calibrating the short circuit current of a solar cell with respect to a given irradiance spectrum are discussed. In conclusion, the need for a sophisticated solar simulator is proportional to the spectral mismatch betwen the spectral response of the reference cell used to set the solar simulator and that of the test cell. The ASTM terrestrial solar irradiance spectrum is recommended as a reference, spectrum and, the used either filtered xenon arc or dichroic filtered tungsten halogen lamps for solar simulation is also recommended.

Matson, R.; Bird, R.; Emery, K.

1981-09-01

147

Nanocrystalline metal electrodes for high-efficiency organic solar cells  

Microsoft Academic Search

We demonstrate that indium (In) nanocrystals can be used as efficient small-work function electrodes for organic solar cells. A Schottky-barrier solar cell consisting of the In nanoelectrodes, a zinc phthalocyanine (ZnPc) film as a p-type organic semiconductor, and a gold counterelectrode were assembled by vacuum evaporation on an indium-tin-oxide substrate. Nanoscopic Schottky barriers, which are the origins of photovoltaic effects,

Tetsuya Taima; Masayuki Chikamatsu; Yuji Yoshida; Kazuhiro Saito; Kiyoshi Yase

2004-01-01

148

Parameterization of solar cells  

NASA Astrophysics Data System (ADS)

The aggregation (sorting) of the individual solar cells into an array is commonly based on a single operating point on the current-voltage (I-V) characteristic curve. An alternative approach for cell performance prediction and cell screening is provided by modeling the cell using an equivalent electrical circuit, in which the parameters involved are related to the physical phenomena in the device. These analytical models may be represented by a double exponential I-V characteristic with seven parameters, by a double exponential model with five parameters, or by a single exponential equation with four or five parameters. In this article we address issues concerning methodologies for the determination of solar cell parameters based on measured data points of the I-V characteristic, and introduce a procedure for screening of solar cells for arrays. We show that common curve fitting techniques, e.g., least squares, may produce many combinations of parameter values while maintaining a good fit between the fitted and measured I-V characteristics of the cell. Therefore, techniques relying on curve fitting criteria alone cannot be directly used for cell parameterization. We propose a consistent procedure which takes into account the entire set of parameter values for a batch of cells. This procedure is based on a definition of a mean cell representing the batch, and takes into account the relative contribution of each parameter to the overall goodness of fit. The procedure is demonstrated on a batch of 50 silicon cells for Space Station Freedom.

Appelbaum, J.; Chait, A.; Thompson, D.

1992-10-01

149

Redistribution of NAVSEC-1 composition on zinc anodes during silver-zinc cell cycling  

Microsoft Academic Search

The present study consisted of analyzing zinc plates for the distribution of the NAVSEC-1 mixture. The mixture consists of 2% cadmium oxide and 1% lead oxide. The effectiveness of these additives to reduce hydrogen evolution and minimize shape change depends on the distribution of the components. Comparisons of virgin zinc plates with baseline and 50 cycle cell plates were made

V. L. Hammersley; S. P. Wharton; B. T. Winter

1997-01-01

150

Zinc and silver migration during rechargeable silver-zinc cell cycling  

Microsoft Academic Search

A study has been established to obtain zinc and silver migration rate data on cellulosic separators derived from a variety of cellulose and cellophane sources in silver-zinc alkaline rechargeable cells. The purpose of the study is to utilize the cycle and wet life data which are, in part, a function of the formation of soft and hard shorting in the

Harlan L. Lewis; Steven P. Wharton

1997-01-01

151

Thin film solar cells  

SciTech Connect

Written for graduate students and R and D scientists and engineers, this text provides a lucid treatment of many facets of materials, technologies, and solid-state physics of thin film solar cell devices. The various types of homo-, hetero-, barrier, and liquid junction solar cells involving amorphous, polycrystalline, and epitaxial semiconductor thin films are all covered. The volume details the basic solid-state physics of junction devices and describes thin film materials and associated preparation, measurement, and analysis techniques, as well as device technology. The authors present a critical comparative analysis of the performance of various types of thin film solar cells in order to focus on the present status of the field and to project future developments.

Chopra, K.L.; Das, S.R.

1983-01-01

152

High Efficiency Multijunction Solar Cells with Finely-Tuned Quantum Wells  

NASA Astrophysics Data System (ADS)

The field of high efficiency (inorganic) photovoltaics (PV) is rapidly maturing in both efficiency goals and cover all cost reduction of fabrication. On one hand, know-how from space industry in new solar cell design configurations and on the other, fabrication cost reduction challenges for terrestrial uses of solar energy, have paved the way to a new generation of PV devices, capable of capturing most of the solar spectrum. For quite a while now, the goal of inorganic solar cell design has been the total (if possible) capture-absorption of the solar spectrum from a single solar cell, designed in such a way that a multiple of incident wavelengths could be simultaneously absorbed. Multi-absorption in device physics indicates parallel existence of different materials that absorb solar photons of different energies. Bulk solid state devices absorb at specific energy thresholds, depending on their respective energy gap (EG). More than one energy gaps would on principle offer new ways of photon absorption: if such a structure could be fabricated, two or more groups of photons could be absorbed simultaneously. The point became then what lattice-matched semiconductor materials could offer such multiple levels of absorption without much recombination losses. It was soon realized that such layer multiplicity combined with quantum size effects could lead to higher efficiency collection of photo-excited carriers. At the moment, the main reason that slows down quantum effect solar cell production is high fabrication cost, since it involves primarily expensive methods of multilayer growth. Existing multi-layer cells are fabricated in the bulk, with three (mostly) layers of lattice-matched and non-lattice-matched (pseudo-morphic) semiconductor materials (GaInP/InGaN etc), where photo-carrier collection occurs in the bulk of the base (coming from the emitter which lies right under the window layer). These carriers are given excess to conduction via tunnel junction (grown between at each interface and connecting the layers in series). This basic idea of a design has proven very successful in recent years, leading to solar cells of efficiency levels well above 30% (Fraunhofer Institute's multi-gap solar cell at 40.8%, and NREL's device at 40.2% respectively). Successful alloys have demonstrated high performance, such as InxGa1 - xP alloys (x (%) of gallium phosphide and (1 - x) (%) of indium phosphide). Other successful candidates, in current use and perpetual cell design consideration, are the lattice-matched GaAs/AlGaAs and InP/GaAs pairs or AlAs/GaAs/GaAs triple layers and alloys, which are heavily used in both solar and the electronics industry.

Varonides, Argyrios C.

153

Solar PV- How A Solar Cell Works  

NSDL National Science Digital Library

The Advanced Technology Environmental and Energy Center (ATEEC) provides this document which will help instructors or anyone who would like to understand the basics of solar power and solar cells. Users must download this resource for viewing, which requires a free log-in. There is no cost to download the item.

Levander, Alejandro

2011-03-03

154

Solar-cell panel simulator  

Microsoft Academic Search

The energy generated by solar cells can be transformed into ac power by means of inverters. In most cases these inverters cannot be tested under real conditions, since large solar-cell arrays are not yet available at reasonable prices. Therefore, a circuit that simulates a solar-cell array has been developed.

D. Baert

1979-01-01

155

Advanced solar cell concepts1  

Microsoft Academic Search

In order to ensure the widespread use of solar photovoltaic technology for terrestrial applications, cost per unit watt must be significantly lower than 1$\\/Watt level. Material limitation of wafer based Si cell technology and efficiency limitation of thin-film solar cell technologies needs to overcome in order to achieve the above- mentioned cost goal. Thermodynamically solar cell efficiencies can be as

C. S. Solanki; G. Beaucarne

2007-01-01

156

NASA Facts, Solar Cells.  

ERIC Educational Resources Information Center

|The design and function of solar cells as a source of electrical power for unmanned space vehicles is described in this pamphlet written for high school physical science students. The pamphlet is one of the NASA Facts Science Series (each of which consists of four pages) and is designed to fit in the standard size three-ring notebook. Review…

National Aeronautics and Space Administration, Washington, DC.

157

Amorphous semiconductor solar cell  

DOEpatents

A solar cell comprising a back electrical contact, amorphous silicon semiconductor base and junction layers and a top electrical contact includes in its manufacture the step of heat treating the physical junction between the base layer and junction layer to diffuse the dopant species at the physical junction into the base layer.

Dalal, Vikram L. (Newark, DE)

1981-01-01

158

ZINC  

EPA Science Inventory

This report summarizes the available information on zinc as it relates to its effects on man and his environment. Zinc is found in most soils, but some areas are deficient in it. Metallurgic operations contribute to zinc contamination in air, water and soil. Trace amounts of zinc...

159

Polymer solar cells.  

PubMed

This article reviews the motivations for developing polymer-based photovoltaics and describes some of the material systems used. Current challenges are identified, and some recent developments in the field are outlined. In particular, recent work to image and control nanostructure in polymer-based solar cells is reviewed, and very recent progress is described using the unique properties of organic semiconductors to develop strategies that may allow the Shockley-Queisser limit to be broken in a simple photovoltaic cell. PMID:23816905

Greenham, Neil C

2013-07-01

160

Controlling the directionality of charge transfer in phthalocyaninato zinc sensitizer for a dye-sensitized solar cell: density functional theory studies.  

PubMed

Density functional theory (DFT) calculation on the molecular structures, charge distribution, molecular orbitals, electronic absorption spectra of a series of eight unsymmetrical phthalocyaninato zinc complexes with one peripheral (E)-2-cyano-3-(5-vinylthiophen-2-yl) acrylic acid substituent at 2 or 3 position as an electron-withdrawing group and a different number of electron-donating amino groups at the remaining peripheral positions (9, 10, 16, 17, 23, 24) of the phthalocyanine ring, namely ZnPc-?-A, ZnPc-?-A-I-NH(2), ZnPc-?-A-II-NH(2), ZnPc-?-A-III-NH(2), ZnPc-?-A-I,II-NH(2), ZnPc-?-A-I,III-NH(2), ZnPc-?-A-II,III-NH(2), and ZnPc-?-A-I,II,III-NH(2), reveals the effects of amino groups on the charge transfer properties of these phthalocyanine derivatives with a typical D-?-A electronic structure. The introduction of amino groups was revealed altering of the atomic charge distribution, lifting the frontier molecular orbital level, red-shift of the near-IR bands in the electronic absorption spectra, and finally resulting in enhanced charge transfer directionality for the phthalocyanine compounds. Along with the increase of the peripheral amino groups at the phthalocyanine ring from 0, 2, 4, to 6, the dihedral angle between the phthalocyanine ring and the average plane of the (E)-2-cyano-3-(5-vinylthiophen-2-yl) acrylic acid substituent increases from 0 to 3.3° in an irregular manner. This is in good contrast to the regular and significant change in the charge distribution, destabilization of frontier orbital energies, and red shift of near-IR bands of phthalocyanine compounds along the same order. In addition, comparative studies indicate the smaller effect of incorporating two amino groups onto the 16 and 17 than on 9 and 10 or 23 and 24 peripheral positions of the phthalocyanine ring onto the aforementioned electronic properties, suggesting the least effect on tuning the charge transfer property of the phthalocyanine compound via introducing two electron-donating amino groups onto the 16 and 17 peripheral positions. As expected, compound ZnPc-?-A-I,III-NH(2) with four amino groups at 9, 10, 23, and 24 positions of the phthalocyanine ring shows the best charge transfer directionality among the three phthalocyaninato zinc complexes with four peripheral amino groups. PMID:21103486

Wan, Liang; Qi, Dongdong; Zhang, Yuexing; Jiang, Jianzhuang

2010-11-22

161

Improved silver\\/zinc secondary cells for underwater applications  

Microsoft Academic Search

Performance improvements in silver\\/zinc technology have been achieved with new developments in additives and separator coatings. These improvements, aimed at increasing the cycle life and energy density of silver\\/zinc cells, were realized through advances in the stateof the-art of the zinc electrode and of the separators, which are the major limitations to this electrochemical couple. To achieve these objectives, two

James Skelton; Roberto Serenyi

1997-01-01

162

Phosphidation of Li4Ti5O12 nanoparticles and their electrochemical and biocompatible superiority for lithium rechargeable batteries.  

PubMed

Phosphidated-Li(4)Ti(5)O(12) shows high capacity with a significantly enhanced kinetics opening new possibilities for ultra-fast charge/discharge of lithium rechargeable batteries. The in vitro cytotoxicity test proves its fabulous cell viability, indicating that the toxicity problem of nanoparticles can be also solved by phosphidation. PMID:21952411

Jo, Mi Ru; Nam, Ki Min; Lee, Youngmin; Song, Kyeongse; Park, Joon T; Kang, Yong-Mook

2011-09-26

163

GRID-CONNECTED SOLAR ENERGY STORAGE USING THE ZINC-BROMINE FLOW BATTERY  

Microsoft Academic Search

The zinc-bromine battery is an emerging energy storage technology, ideally suited for solar load-shifting applications requiring 2 to 10 hours of energy storage. The energy density and cycle life of this advanced battery makes it attractive for applications where conventional lead-acid batteries face limitations due to size, weight, or cycle life. To test the viability of the zinc-bromine battery for

Benjamin L. Norris; Greg J. Ball; Peter Lex; Scaini Vince

164

EDITORIAL: Nanostructured solar cells Nanostructured solar cells  

NASA Astrophysics Data System (ADS)

Conversion into electrical power of even a small fraction of the solar radiation incident on the Earth's surface has the potential to satisfy the world's energy demands without generating CO2 emissions. Current photovoltaic technology is not yet fulfilling this promise, largely due to the high cost of the electricity produced. Although the challenges of storage and distribution should not be underestimated, a major bottleneck lies in the photovoltaic devices themselves. Improving efficiency is part of the solution, but diminishing returns in that area mean that reducing the manufacturing cost is absolutely vital, whilst still retaining good efficiencies and device lifetimes. Solution-processible materials, e.g. organic molecules, conjugated polymers and semiconductor nanoparticles, offer new routes to the low-cost production of solar cells. The challenge here is that absorbing light in an organic material produces a coulombically bound exciton that requires dissociation at a donor-acceptor heterojunction. A thickness of at least 100 nm is required to absorb the incident light, but excitons only diffuse a few nanometres before decaying. The problem is therefore intrinsically at the nano-scale: we need composite devices with a large area of internal donor-acceptor interface, but where each carrier has a pathway to the respective electrode. Dye-sensitized and bulk heterojunction cells have nanostructures which approach this challenge in different ways, and leading research in this area is described in many of the articles in this special issue. This issue is not restricted to organic or dye-sensitized photovoltaics, since nanotechnology can also play an important role in devices based on more conventional inorganic materials. In these materials, the electronic properties can be controlled, tuned and in some cases completely changed by nanoscale confinement. Also, the techniques of nanoscience are the natural ones for investigating the localized states, particularly at surfaces and interfaces, which are often the limiting factor in device performance. This issue provides concrete examples of how the techniques of nanoscience and nanotechnology can be used to understand, control and optimize the performance of novel photovoltaic devices. We are grateful to the contributors for submitting high-quality papers around a common theme, even though they may not normally consider their work to fall under the banner of 'nanotechnology'. We would also like to thank the editorial and production staff at Nanotechnology for their efficient and speedy work in putting this issue together.

Greenham, Neil C.; Grätzel, Michael

2008-10-01

165

Large Retractable Solar Cell Array.  

National Technical Information Service (NTIS)

The main activities on the Large Retractable Solar Cell Array(LRSCA) program during the fifth quarterly reporting period consisted of completion of the detailed drawings of the solar array, drum mechanism, and control electronics unit (CEU). Circuit desig...

E. O. Felkel G. Wolff M. C. Olson W. N. Turner R. E. Daniel

1969-01-01

166

Silicon Solar Cell Turns 50  

SciTech Connect

This short brochure describes a milestone in solar (or photovoltaic, PV) research-namely, the 50th anniversary of the invention of the first viable silicon solar cell by three researchers at Bell Laboratories.

Perlin, J.

2004-08-01

167

Separation composition evaluation in model rechargeable silver-zinc cells  

Microsoft Academic Search

In previous reports, the evaluation of Viskase sausage casings (SCs) in a variety of configurations for silver\\/zinc rechargeable cells has been reported. The conclusions have been that several layers of SC, while providing improved resistance to silver migration acid zinc dendrite growth compared to standard cellophane film, also impart increased internal impedance which leads to faster capacity loss in comparison

H. Lewis; S. Henderson; T. Danko

2001-01-01

168

Gallium Phosphide and the Gallium Arsenide-Gallium Phosphide System, Data Sheets.  

National Technical Information Service (NTIS)

These data sheets present a compilation of a wide range of electrical, optical and energy values for gallium phosphide and the gallium arsenidegallium phosphide system in bulk and film form. Electrical properties include lifetime and thermoelectric effect...

M. Neuberger

1965-01-01

169

Fundamental Studies of the Metallurgical, Electrical, and Optical Properties of Gallium Phosphide and Gallium Phosphide Alloys.  

National Technical Information Service (NTIS)

Abstracts, bibliographic data, oral presentations, and published papers on (1) Diffusion of Sulfur in Gallium Phosphide and Gallium Arsenide, and (2) Properties of Gallium Phosphide Schottky Barrier Rectifiers for Use at High Temperature are presented.

1972-01-01

170

Radiation Effects on Gallium Arsenide Phosphide and Gallium Phosphide Schottky Barrier Diodes.  

National Technical Information Service (NTIS)

Gallium arsenide phosphide (GaAsP) and gallium phosphide (GaP) Schottky barrier diodes were fabricated and the transient ionizing and stable fast neutron radiation effects on these diodes were determined. (Author)

D. A. Neamen W. W. Grannemann

1971-01-01

171

Zinc.  

National Technical Information Service (NTIS)

This report summarizes the available information on zinc as it relates to its effects on man and his environment. Zinc is found in most soils, but some areas are deficient in it. Metallurgic operations contribute to zinc contamination in air, water and so...

1978-01-01

172

Prion protein facilitates uptake of zinc into neuronal cells  

PubMed Central

Zinc is released into the synaptic cleft upon exocytotic stimuli, although the mechanism for its reuptake into neurons is unresolved. Here we show that the cellular prion protein enhances the uptake of zinc into neuronal cells. This prion-protein-mediated zinc influx requires the octapeptide repeats and amino-terminal polybasic region in the prion protein, but not its endocytosis. Selective antagonists of ?-amino-3-hydroxy-5-methyl-4-isoxazolepropionate (AMPA) receptors block the prion protein-mediated zinc uptake, and the prion protein co-immunoprecipitates with both GluA1 and GluA2 AMPA receptor subunits. Zinc-sensitive intracellular tyrosine phosphatase activity is decreased in cells expressing prion protein and increased in the brains of prion-protein-null mice, providing evidence of a physiological consequence of this process. Prion protein-mediated zinc uptake is ablated in cells expressing familial associated mutants of the protein and in prion-infected cells. These data suggest that alterations in the cellular prion protein-mediated zinc uptake may contribute to neurodegeneration in prion and other neurodegenerative diseases.

Watt, Nicole T.; Taylor, David R.; Kerrigan, Talitha L.; Griffiths, Heledd H.; Rushworth, Jo V.; Whitehouse, Isobel J.; Hooper, Nigel M.

2012-01-01

173

Heteroepitaxial growth of gallium phosphide on silicon  

Microsoft Academic Search

A new method of growing gallium phosphide on a silicon substrate is presented. The method includes an extra but simple process\\u000a of depositing a thin phosphorus layer on a silicon substrate prior to the growth of gallium phosphide by a so-called halide\\u000a transport method. Electronic and optical properties of the heterojunctions indicate that the interfaces between the gallium\\u000a phosphide layers

T. Katoda; M. Kishi

1980-01-01

174

Effect of zinc supplementation on incidence of infections and hospital admissions in sickle cell disease (SCD)  

Microsoft Academic Search

Zinc deficiency is a common nutritional problem in adult sickle-cell disease (SCD) pa- tients. Hyperzincuria and increased requirement of zinc due to continued hemolysis in SCD are probable bases for zinc deficiency in these patients. Zinc deficiency affects adversely T-helper1 (TH1) functions and cell mediated immunity and interleukin (IL)-2 production is decreased in zinc deficient subjects. We hypothesized that zinc

Ananda S. Prasad; Frances W. J. Beck; Joseph Kaplan; Pranatharthi H. Chandrasekar; Jesus Ortega; James T. Fitzgerald; Paul Swerdlow

1999-01-01

175

Evaluation of methods for analyzing silver-zinc cells  

Microsoft Academic Search

Various methods of analyzing silver-zinc cells have been evaluated by application of the test methods to a failure-analysis program for large primary silver-zinc cells. The analysis methods included physical examination, wet chemical methods, and instrumental chemical techniques. The analysis methods have been evaluated in terms of labor required, problems encountered, and in terms of usefulness, accuracy, and precision. Physical examination

D. P. Hafen

1978-01-01

176

Amorphous silicon solar cells  

NASA Astrophysics Data System (ADS)

The photoconductive response of Schottky-barrier and p-i-n solar cell structures was analyzed. It shows that the photoconductivity determines the fill factor, rather than the dark current, as in crystalline silicon cells. An analysis of the I-V curves of p-i-n cells shows that the electron and hole drift lengths are comparable. High conductivity p and n type films (sigma = 1-10 (LAMBDA) (+1).cm(+1)) were produced in an rf discharge for T/sub s/ 4000 C and in a dc cathodic discharge for T/sub s/ 3500 C. Diffusion lengths of approx. 0.8 (SIGMA)m were measured in undoped a-Si:H films at illumination levels of approx. 0.1 Sun. The activation energy of the diffusion length is 0.28 eV. The technique for measuring the diffusion length was improved by a liquid Schottky-barrier contact. It is confirmed that carbon alloying of the p layer improves the performance of p-i-n cells illuminated through that layer and also that the stability is better for cells illuminated through the p layer. It is indicated that a major factor determining the efficiency of ITO/n-i-p cells is the ITC/n contact. Several parameters were determined that affect device stability. A gradual boron profile enhances stability, as does a thin, undoped layer. Increased oxygen contamination increases the degradation of a-Si:H p-i-n cells.

Carlson, D. E.; Crandall, R. S.; Dresner, J.; Goldstein, D.; Hanak, J. J.; Moore, A. R.; Schade, R. E.; Staebler, D. L.; Weakliem, H. A.; Williams, R.

1981-05-01

177

Development and fabrication of large vented nickel-zinc cells  

Microsoft Academic Search

A preliminary cell design for a 300AH vented nickel-zinc cell was established based on volume requirements and cell component materials selected by NASA Lewis Research Center. A 100AH cell configuration was derived from the 300AH cell design utilizing the same size electrodes, separators, and cell terminal hardware. The first cells fabricated were four groups of three cells each in the

C. P. Donnel III

1975-01-01

178

A simple route for photocatalytic degradation of phenol in aqueous zinc oxide suspension using solar energy  

Microsoft Academic Search

In a laboratory study, the effectiveness of zinc oxide-mediated solar photocatalytic degradation of phenol was examined. The effect of various parameters like concentration of substrate, amount of photocatalyst, pH and irradiation time on the efficiency of photocatalytic degradation was studied. The demineralization of substrate was checked by Chemical Oxygen Demand (COD) reduction method. The photocatalytic degradation of phenol was found

S. K. Pardeshi; A. B. Patil

2008-01-01

179

Life cycle assessment of the conventional and solar thermal production of zinc and synthesis gas  

Microsoft Academic Search

The current industrial productions of zinc and synthesis gas are characterized by their high energy consumption and their concomitant environmental pollution. Emissions of greenhouse gases (GHG) could be reduced substantially by combining both productions and by replacing fossil fuels with concentrated solar energy as the source of high-temperature process heat. The extent of such a GHG mitigation has been quantified

Miriam Werder; Aldo Steinfeld

2000-01-01

180

Improved bulk heterojunction organic solar cells employing C70 fullerenes  

NASA Astrophysics Data System (ADS)

We show that the fullerene C70 is suitable to replace fullerene C60, which is commonly used as electron transporter and acceptor in small-molecule organic solar cells. It is shown that the higher absorption of C70 leads to high external quantum efficiencies of over 50% in the spectral range of 500-700 nm. By optimizing the energy level alignment to hole transport layers, the absorption, and the ratio of C70:zinc phthalocyanine (ZnPc) in a bulk heterojunction solar cell, an efficiency of ?=2.87% is achieved. This is a substantial improvement over an identical solar cell employing C60 having ?=2.27%. The efficiency increase is due to a higher photocurrent, while fill factor and open-circuit voltage for C70 and C60-containing organic solar cells remain comparable.

Pfuetzner, Steffen; Meiss, Jan; Petrich, Annette; Riede, Moritz; Leo, Karl

2009-06-01

181

Quantum junction solar cells.  

PubMed

Colloidal quantum dot solids combine convenient solution-processing with quantum size effect tuning, offering avenues to high-efficiency multijunction cells based on a single materials synthesis and processing platform. The highest-performing colloidal quantum dot rectifying devices reported to date have relied on a junction between a quantum-tuned absorber and a bulk material (e.g., TiO(2)); however, quantum tuning of the absorber then requires complete redesign of the bulk acceptor, compromising the benefits of facile quantum tuning. Here we report rectifying junctions constructed entirely using inherently band-aligned quantum-tuned materials. Realizing these quantum junction diodes relied upon the creation of an n-type quantum dot solid having a clean bandgap. We combine stable, chemically compatible, high-performance n-type and p-type materials to create the first quantum junction solar cells. We present a family of photovoltaic devices having widely tuned bandgaps of 0.6-1.6 eV that excel where conventional quantum-to-bulk devices fail to perform. Devices having optimal single-junction bandgaps exhibit certified AM1.5 solar power conversion efficiencies of 5.4%. Control over doping in quantum solids, and the successful integration of these materials to form stable quantum junctions, offers a powerful new degree of freedom to colloidal quantum dot optoelectronics. PMID:22881834

Tang, Jiang; Liu, Huan; Zhitomirsky, David; Hoogland, Sjoerd; Wang, Xihua; Furukawa, Melissa; Levina, Larissa; Sargent, Edward H

2012-08-16

182

An Introduction to Solar Cells  

ERIC Educational Resources Information Center

|Most likely, solar cells will play a significant role in this country's strategy to address the two interrelated issues of global warming and dependence on imported oil. The purpose of this paper is to present an explanation of how solar cells work at an introductory high school, college, or university physics course level. The treatment…

Feldman, Bernard J.

2010-01-01

183

Flexible solar cells for clothing  

Microsoft Academic Search

Integration of flexible solar cells into clothing can provide power for portable electronic devices. Photovoltaics is the most advanced way of providing electricity far from any mains supply, although it suffers from the limits of ambient light intensity. But the energy demand of portable devices is now low enough that clothing-integrated solar cells are able to power most mobile electronics.

Markus B. Schubert; Jürgen H. Werner

2006-01-01

184

Colloidal quantum dot solar cells  

NASA Astrophysics Data System (ADS)

Solar cells based on solution-processed semiconductor nanoparticles -- colloidal quantum dots -- have seen rapid advances in recent years. By offering full-spectrum solar harvesting, these cells are poised to address the urgent need for low-cost, high-efficiency photovoltaics.

Sargent, Edward H.

2012-03-01

185

Carbon Nanotube Solar Cells  

PubMed Central

We present proof-of-concept all-carbon solar cells. They are made of a photoactive side of predominantly semiconducting nanotubes for photoconversion and a counter electrode made of a natural mixture of carbon nanotubes or graphite, connected by a liquid electrolyte through a redox reaction. The cells do not require rare source materials such as In or Pt, nor high-grade semiconductor processing equipment, do not rely on dye for photoconversion and therefore do not bleach, and are easy to fabricate using a spray-paint technique. We observe that cells with a lower concentration of carbon nanotubes on the active semiconducting electrode perform better than cells with a higher concentration of nanotubes. This effect is contrary to the expectation that a larger number of nanotubes would lead to more photoconversion and therefore more power generation. We attribute this to the presence of metallic nanotubes that provide a short for photo-excited electrons, bypassing the load. We demonstrate optimization strategies that improve cell efficiency by orders of magnitude. Once it is possible to make semiconducting-only carbon nanotube films, that may provide the greatest efficiency improvement.

Klinger, Colin; Patel, Yogeshwari; Postma, Henk W. Ch.

2012-01-01

186

Lunar production of solar cells  

NASA Astrophysics Data System (ADS)

The feasibility of manufacturing of solar cells on the moon for spacecraft applications is examined. Because of the much lower escape velocity, there is a great advantage in lunar manufacture of solar cells compared to Earth manufacture. Silicon is abundant on the moon, and new refining methods allow it to be reduced and purified without extensive reliance on materials unavailable on the moon. Silicon and amorphous silicon solar cells could be manufactured on the moon for use in space. Concepts for the production of a baseline amorphous silicon cell are discussed, and specific power levels are calculated for cells designed for both lunar and Earth manufacture.

Landis, Geoffrey A.; Perino, Maria Antonietta

1989-05-01

187

Thin Film Solar Cell Workshop.  

National Technical Information Service (NTIS)

A summation of responses to questions posed to the thin-film solar cell workshop and the ensuing discussion is provided. Participants in the workshop included photovoltaic manufacturers (both thin film and crystalline), cell performance investigators, and...

J. Armstrong F. Jeffrey

1993-01-01

188

Silver--zinc electric storage cells. [semipermeable membrane as separator  

Microsoft Academic Search

A rechargeable silver--zinc electric storage cell is described which comprises a casing enclosing a silver electrode and a zinc electrode, a separator comprising an imperforate semi-permeable membrane disposed between the electrodes, and an electrolyte. The membrane is sealed to the casing so that the only ion path between the electrodes is through the membrane. The imperforate semi-permeable membrane comprises a

H. T. Mote; L. Hajdu; B. Ronay

1974-01-01

189

Fabrication of boron-phosphide neutron detectors  

SciTech Connect

Boron phosphide is a potentially viable candidate for high neutron flux neutron detectors. The authors have explored chemical vapor deposition methods to produce such detectors and have not been able to produce good boron phosphide coatings on silicon carbide substrates. However, semi-conducting quality films have been produced. Further testing is required.

Fitzsimmons, M.; Pynn, R.

1997-07-01

190

Upconversion in solar cells  

PubMed Central

The possibility to tune chemical and physical properties in nanosized materials has a strong impact on a variety of technologies, including photovoltaics. One of the prominent research areas of nanomaterials for photovoltaics involves spectral conversion. Modification of the spectrum requires down- and/or upconversion or downshifting of the spectrum, meaning that the energy of photons is modified to either lower (down) or higher (up) energy. Nanostructures such as quantum dots, luminescent dye molecules, and lanthanide-doped glasses are capable of absorbing photons at a certain wavelength and emitting photons at a different (shorter or longer) wavelength. We will discuss upconversion by lanthanide compounds in various host materials and will further demonstrate upconversion to work for thin-film silicon solar cells.

2013-01-01

191

Germanium Nanocrystal Solar Cells  

NASA Astrophysics Data System (ADS)

Greenhouse gas concentrations in the atmosphere are approaching historically unprecedented levels from burning fossil fuels to meet the ever-increasing world energy demand. A rapid transition to clean energy sources is necessary to avoid the potentially catastrophic consequences of global warming. The sun provides more than enough energy to power the world, and solar cells that convert sunlight to electricity are commercially available. However, the high cost and low efficiency of current solar cells prevent their widespread implementation, and grid parity is not anticipated to be reached for at least 15 years without breakthrough technologies. Semiconductor nanocrystals (NCs) show promise for cheap multi-junction photovoltaic devices. To compete with photovoltaic materials that are currently commercially available, NCs need to be inexpensively cast into dense thin films with bulk-like electrical mobilities and absorption spectra that can be tuned by altering the NC size. The Group II-VI and IV-VI NC communities have had some success in achieving this goal by drying and then chemically treating colloidal particles, but the more abundant and less toxic Group IV NCs have proven more challenging. This thesis reports thin films of plasma-synthesized Ge NCs deposited using three different techniques, and preliminary solar cells based on these films. Germanium tetrachloride is dissociated in the presence of hydrogen in a nonthermal plasma to nucleate Ge NCs. Transmission electron microscopy and X-ray diffraction indicate that the particles are nearly monodisperse (standard deviations of 10-15% the mean particle diameter) and the mean diameter can be tuned from 4-15 nm by changing the residence time of the Ge NCs in the plasma. In the first deposition scheme, a Ge NC colloid is formed by reacting nanocrystalline powder with 1-dodecene and dispersing the functionalized NCs in a solvent. Films are then formed on substrates by drop-casting the colloid and allowing it to dry. As-deposited films are electrically insulating due to the long hydrocarbon molecules separating neighboring particles; however, mass spectrometry shows that annealing treatments successfully decompose these molecules. After annealing at 250 °C, Ge NC films exhibit conductivities as large as 10-6 S/cm. In the second film deposition scheme, a Ge NC colloid is formed by dispersing Ge NCs in select solvents without further surface modification. While these "bare" NCs quickly agglomerate and flocculate in nearly all non-polar solvents, they remain stable in benzonitrile and 1,2-dichlorobenzene, among others. Thin-film field-effect transistors have been fabricated by spinning Ge NC colloids onto substrates and the films have been subjected to various annealing procedures. The devices show n-type, p -type, or ambipolar behavior depending on the annealing conditions, with Ge NC films annealed at 300°C exhibiting electron saturation mobilities greater than 10-2 cm2/Vs and on-to-off ratios of 104. The final film deposition scheme involves the impaction of Ge NCs onto substrates downstream of the synthesis plasma via acceleration of the NCs through an orifice. This technique produces highly uniform films with densities greater than 50% of the density of bulk Ge. By varying the size of the Ge NCs, we have measured films with band gaps ranging from the bulk value of 0.7 eV to over 1.1 eV for films of 4 nm Ge NCs. Having deposited dense thin films with tunable band gaps and respectable mobilities, we have begun fabricating bilayer solar cells consisting of heterojunctions between Ge NC films and P3HT, Si NCs, or Si wafers. Preliminary devices exhibit opencircuit voltages and short-circuit currents as large as 0.3 V and 4 mA/cm 2, respectively.

Holman, Zachary Charles

192

Multiple Exciton Generation Solar Cells  

SciTech Connect

Heat loss is the major factor limiting traditional single junction solar cells to a theoretical efficiency of 32%. Multiple Exciton Generation (MEG) enables efficient use of the solar spectrum yielding a theoretical power conversion efficiency of 44% in solar cells under 1-sun conditions. Quantum-confined semiconductors have demonstrated the ability to generate multiple carriers but present-day materials deliver efficiencies far below the SQ limit of 32%. Semiconductor quantum dots of PbSe and PbS provide an active testbed for developing high-efficiency, inexpensive solar cells benefitting from quantum confinement effects. Here, we will present recent work of solar cells employing MEG to yield external quantum efficiencies exceeding 100%.

Luther, J. M.; Semonin, O. E.; Beard, M. C.; Gao, J.; Nozik, A. J.

2012-01-01

193

Lithium counterdoped silicon solar cell  

Microsoft Academic Search

The resistance to radiation damage of an n(+)p boron doped silicon solar cell is improved by lithium counterdoping. Even though lithium is an n-dopant in silicon, the lithium is introduced in small enough quantities so that the cell base remains p-type. The lithium is introduced into the solar cell wafer by implantation of lithium ions whose energy is about 50

I. Weinberg; H. W. Brandhorst Jr.

1986-01-01

194

Lithium counterdoped silicon solar cell  

Microsoft Academic Search

The resistance to radiation damage of an n(+)p boron doped silicon solar cell is improved by lithium counterdoping. Even though lithium is an n-dopant in silicon, the lithium is introduced in small enough quantities so that the cell base remains p-type. The lithium is introduced into the solar cell wafer by implantation of lithium ions whose energy is about 50

I. Weinberg; Brandhorst H. W. Jr

1984-01-01

195

Zinc  

MedlinePLUS

... ulcers and promoting weight gain in people with eating disorders such as anorexia nervosa. Some people use zinc ... weight gain and improving depression in people with eating disorders such as anorexia nervosa. Treating hypogeusia, a rare ...

196

Panel for solar energy cells  

Microsoft Academic Search

A panel for mounting solar energy cells, and particularly those cells upon which light is to be concentrated, includes an enclosure for holding the cells and has at least one wall formed from a good conductor of heat. The cells are mounted within the enclosure on a resinous cushion that is a relatively good conductor of heat and a poor

Varadi

1977-01-01

197

Inhibitory effect of zinc on glucose-stimulated zinc/insulin secretion in an insulin-secreting ?-cell line.  

PubMed

Diminished or inappropriate secretion of insulin is associated with type II diabetes. The cellular/molecular mechanism coupled with the regulation of insulin secretion is still under intense investigation. Divalent ion zinc (Zn(2+)) is co-packaged and co-secreted with insulin and is intimately involved in the process of insulin biosynthesis and the maturation of insulin secretory granules. The study reported here investigated glucose-stimulated zinc secretion (GSZS) and the effect of zinc on glucose-stimulated insulin secretion (GSIS) in the HIT-T15 pancreatic ?-cell line. Zinc secretion was measured using a newly developed fluorescent zinc imaging approach, and the insulin secretion was measured using an enzyme-linked immunosorbent assay. There was apparent granular-like zinc staining in ?-cells. The application of glucose induced detectable zinc secretion or GSZS. Like GSIS, GSZS was dependent on the glucose concentration (5-20 mm) and the presence of extracellular calcium. The application of a zinc chelator enhanced GSZS. When brief paired-pulse glucose stimulations, which involve the initial glucose stimulation followed by a second round of glucose stimulation, were applied, zinc secretion or GSZS that followed the first pulse was inhibited. This inhibition was reversed by zinc chelation, suggesting a feedback mechanism on GSZS by zinc secreted from ?-cells. Finally, the application of zinc (50 ?m) strongly inhibited GSIS as measured by enzyme-linked immunosorbent assay. The present study suggests that insulin secretion is regulated by co-secreted zinc that may act as an autocrine inhibitory modulator. PMID:23603373

Slepchenko, Kira G; James, Calvin B L; Li, Yang V

2013-04-19

198

Toll-like receptor–mediated regulation of zinc homeostasis influences dendritic cell function  

Microsoft Academic Search

Zinc is a trace element that is essential for the function of many enzymes and transcription factors. Zinc deficiency results in defects in innate and acquired immune responses. However, little is known about the mechanism(s) by which zinc affects immune cell function. Here we show that stimulation with the Toll-like receptor 4 agonist lipopolysaccharide (LPS) altered the expression of zinc

Hidemitsu Kitamura; Hideyuki Morikawa; Hokuto Kamon; Megumi Iguchi; Shintaro Hojyo; Toshiyuki Fukada; Susumu Yamashita; Tsuneyasu Kaisho; Shizuo Akira; Masaaki Murakami; Toshio Hirano

2006-01-01

199

Programmed cell death (apoptosis) in lymphoid and myeloid cell lines during zinc deficiency.  

PubMed Central

Three human cell lines of lymphoid (Molt-3 and Raji) or myeloid (HL-60) origin were maintained in vitro under zinc-sufficient or zinc-deficient conditions. Under these conditions, cell proliferation, viability and mode of death (apoptotic or necrotic) were assessed. All three cell types decreased their proliferative capacity and viability under conditions of zinc deficiency. Cell death in the HL-60 and Raji cultures occurred primarily via apoptosis, while most cells in zinc-deficient Molt-3 cultures died via necrosis. Apoptosis in zinc-deficient cultures of HL-60 and Raji cells was characterized by a slow decline in culture viability as cells with condensed and fragmented nuclear DNA appeared. These morphological changes were accompanied by an increase in cell buoyant density, which allowed separation of viable apoptotic cells from their non-apoptotic counterparts by means of percoll stepdensity gradients. Necrosis in zinc-deficient Molt-3 cultures was characterized by rapid loss of cell culture viability as these cells underwent direct lysis. Intact necrotic cells were easily identified by the flocculated state of their chromatin as well as the decreased basophilia of their cytoplasm. Analysis of DNA from apoptotic HL-60 and Raji cells revealed that internucleosomal DNA degradation, indicative of endogenous endonuclease activation, had occurred, whereas the nuclear DNA of necrotic Molt-3 cells remained relatively unfragmented. The different modes of cell death evoked may reflect the relative sensitivities of cells of these lineages to zinc levels in vivo. Images Fig. 4

Martin, S J; Mazdai, G; Strain, J J; Cotter, T G; Hannigan, B M

1991-01-01

200

Mechanically refuelable zinc/air electric vehicle cells  

NASA Astrophysics Data System (ADS)

Refuelable zinc/air batteries have long been considered for motive as well as stationary power because of a combination of high specific energy, low initial cost, and the possibility of mechanical recharge by electrolyte exchange and additions of metallic zinc. In this context, advanced slurry batteries, stationary packed bed cells, and batteries offering replaceable cassettes have been reported recently. The authors are developing self-feeding, particulate-zinc/air batteries for electric vehicle applications. Emissionless vehicle legislation in California motivated efforts to consider a new approach to providing an electric vehicle with long range (400 km), rapid refueling (10 minutes) and highway safe acceleration - factors which define the essential functions of common automobiles. Such an electric vehicle would not compete with emerging secondary battery vehicles in specialized applications (commuting vehicles, delivery trucks). Rather, different markets would be sought where long range or rapid range extension are important. Examples are: taxis, continuous-duty fork-lift trucks and shuttle busses, and general purpose automobiles having modest acceleration capabilities. In the long range, a mature fleet would best use regional plants to efficiently recover zinc from battery reaction products. One option would be to use chemical/thermal reduction to recover the zinc. The work described focuses on development of battery configurations which efficiently and completely consume zinc particles, without clogging or changing discharge characteristics.

Noring, J.; Gordon, S.; Maimoni, A.; Spragge, M.; Cooper, J. F.

1992-12-01

201

Large Retractable Solar Cell Array.  

National Technical Information Service (NTIS)

The main activity on the Large Retractable Solar Cell Array (LRSCA) program during the third quarterly reporting period consisted of the completion of the analysis of a majority of the major subsystem components, start of detailed drawings, completion of ...

G. Wolff E. O. Felkel

1969-01-01

202

Lithium Implanted Solar Cells, Data.  

National Technical Information Service (NTIS)

The report contains the identification and processing description of all samples processed and the tabulated measurement data obtained on phosphorus diffused, lithium implanted, p-type silicon solar cell blanks. (Author)

D. A. Smith J. L. Hartke

1973-01-01

203

Thin-film solar cells  

Microsoft Academic Search

The rapid progress that is being made with inorganic thin-film photovoltaic (PV) technologies, both in the laboratory and in industry, is reviewed. While amorphous silicon based PV modules have been around for more than 20 years, recent industrial developments include the first polycrystalline silicon thin-film solar cells on glass and the first tandem solar cells based on stacks of amorphous and

Armin G. Aberle

2009-01-01

204

CCMR: Nanocrystal Sensitized Solar Cells  

NSDL National Science Digital Library

Nanocrystal sensitized solar cells demonstrate a possible cheap solution to practical device manufacture. This research examined the feasibility of using lead sulfide nanocrystals to sensitize tin dioxide and titanium dioxide substrates for the purpose of making a functioning photovoltaic device. Challenges included optimizing the substrate materials as well as the thin films made from them. Results indicate that titanium dioxide produces more suitable thin films than tin dioxide. Also, the methods employed did produce a functioning solar cell after optimization.

Perry, Alexis

2009-08-15

205

Thermophotovoltaic Cells on Zinc Diffused Polycrystalline GaSb  

SciTech Connect

For the first time, it has been demonstrated that thermophotovoltaic cells made of polycrystalline GaSb with small grain sizes (down to 100 x 100 {micro}m) have similar characteristics to the best Zinc diffused single crystal GaSb cells with identified device parameters. The grain boundaries in polycrystalline GaSb do not degrade TPV cell parameters, indicating that such material can be used for high-efficiency thermophotovoltaic cells.

Sulima, O.V.; Bett, A.W.; Dutta, P.S.; Ehsani, H.; Gutmann, R.J.

2000-05-01

206

Properties of zinc phosphide\\/zinc oxide heterojunctions  

Microsoft Academic Search

The properties of p-ZnâPâ\\/n-ZnO heterojunctions prepared by sputter deposition of ZnO onto ZnâPâ substrate are investigated. Analysis of the experimental data indicates an interface state density greater than 10¹² cm⁻² and a capture cross section on the order of 10⁻¹³ cm². Using the experimental data a band diagram for ZnâPâ\\/ZnO heterojunction is proposed. Mechanisms responsible for the low, open-circuit voltage

P. S. Nayar

1982-01-01

207

Properties of zinc phosphide\\/zinc oxide heterojunctions  

Microsoft Academic Search

The properties of p-Zn3P2\\/n-ZnO heterojunctions prepared by sputter deposition of ZnO onto Zn3P2 substrate are investigated. Analysis of the experimental data indicates an interface state density greater than 1012 cm?2 and a capture cross section on the order of 10?13 cm2. Using the experimental data a band diagram for Zn3P2\\/ZnO heterojunction is proposed. Mechanisms responsible for the low, open-circuit voltage

P. S. Nayar

1982-01-01

208

Radiation effects in solar cells  

NASA Astrophysics Data System (ADS)

Two types of space solar cells, silicon single-junction and InGaP/GaAs/Ge triple-junction (3J) solar cells, have been primarily adopted for spacecraft. The conversion efficiencies of the solar cells under AM0, 1 sun condition are ~17% for silicon and ~30% for 3J cells. Radiation degradation occurs in space due to high-energy electrons and protons existing in space environment. The degradation is caused by radiation induced crystal defects which act as minority-carrier recombination centers and majority-carrier trap centers. The 3J cells are superior radiation resistant to the silicon cells, and this is mainly because the InGaP top-subcell has property of very high radiation resistance.

Imaizumi, Mitsuru; Ohshima, Takeshi

2013-05-01

209

Crystal and electronic structures of CaAl{sub 2}Si{sub 2}-type rare-earth copper zinc phosphides RECuZnP{sub 2} (RE=Pr, Nd, Gd-Tm, Lu)  

SciTech Connect

The quaternary rare-earth phosphides RECuZnP{sub 2} (RE=Pr, Nd, Gd-Tm, Lu) have been prepared by reaction of the elements at 900 {sup o}C, completing this versatile series which forms for nearly all RE metals. They adopt the trigonal CaAl{sub 2}Si{sub 2}-type structure (Pearson symbol hP5, space group P3-bar m1, Z=1), as confirmed by single-crystal X-ray diffraction analysis on ErCuZnP{sub 2} and powder X-ray diffraction analysis on the remaining members. The Cu and Zn atoms are assumed to be disordered over the single transition-metal site. Band structure calculations on a hypothetically ordered YCuZnP{sub 2} model suggest a semimetal, with a zero band gap between the valence and conduction bands. This electronic structure is supported by XPS valence band spectra for RECuZnP{sub 2} (RE=Gd-Er), in which the intensity drops off smoothly at the Fermi edge. The absence of a band gap permits the electron count to deviate from the precise value of 16 e{sup -} per formula unit, as demonstrated by the formation of a solid solution in GdCu{sub x}Zn{sub 2-x}P{sub 2} (1.0{<=}x{<=}1.3), while still retaining the CaAl{sub 2}Si{sub 2}-type structure. Because the Cu 2p XPS spectra indicate that the Cu atoms are always monovalent, the substitution of Cu for Zn leads to a decrease in electron count and a lowering of the Fermi level in the valence band. The magnetic susceptibility of RECuZnP{sub 2} (RE=Gd-Er), which obeys the Curie-Weiss law, confirms the presence of trivalent RE atoms. -- Graphical abstract: The absence of a band gap in the semimetallic quaternary rare-earth phosphides RECuZnP{sub 2} permits the formation of a solid solution such as GdCu{sub x}Zn{sub 2-x}P{sub 2} through hole-doping of the valence band. Display Omitted

Blanchard, Peter E.R.; Stoyko, Stanislav S.; Cavell, Ronald G. [Department of Chemistry, University of Alberta, Edmonton, Alberta, Canada T6G 2G2 (Canada); Mar, Arthur, E-mail: arthur.mar@ualberta.c [Department of Chemistry, University of Alberta, Edmonton, Alberta, Canada T6G 2G2 (Canada)

2011-01-15

210

Silver Electrode as a Sensor for Determination of Zinc in Cell Cultivation Medium  

Microsoft Academic Search

Use of the silver electrode as a sensor for the monitoring of zinc in cell growth medium is described. Zinc at silver electrodes provides specific voltammetric signal, which is affected by solution components. Signals of zinc ions in phosphate buffer solutions with and without cell growth medium were compared. Common DMEM cell culture medium was used for the cultivation of

René Kizek; Libuše Trnková; Sabina Šev???ková; Jan Šmarda; František Jelen

2002-01-01

211

A regenerative zinc air fuel cell for industrial and specialty vehicles  

Microsoft Academic Search

Metallic Power has demonstrated a regenerative zinc\\/air fuel cell for applications in industrial and specialty vehicles. The fuel cell uses zinc pellets and atmospheric oxygen to generate electric current. The reaction product is zinc oxide, which is collected in a tank. In its present stage of development, the 36 V fuel cell will deliver approximately 6 kWh, with a maximum

S. Smedley

2000-01-01

212

Establishment of NIMT Zinc Fixed-Point Cell  

NASA Astrophysics Data System (ADS)

One of the research programs for the Thermometry Metrology Department at the National Institute of Metrology (Thailand), NIMT, is establishment of its own fixed-point cells. Among the fixed-point cells adopted for the realization of the International Temperature Scale of 1990 (ITS-90), NIMT has chosen the zinc fixed point to start the program. The fabrication and the initial evaluation of the zinc fixed-point cell were conducted at the National Metrology Institute of Japan, NMIJ. The cell fabrication was following the design and procedures developed by the NMIJ. In the cell fabrication, a 6N nominal purity zinc metal cylinder ingot was used. The metal ingot was collected in a graphite crucible under an argon gas atmosphere. The new fixed-point cell was compared with the old fixed-point cells already owned by NIMT, namely, one open-type cell and one sealed-type cell by direct cell comparisons. Since the ingot was equipped with a detail impurity element analysis, it is possible to calculate the effect coming from the existence of the impurities based on, for example, the sum of individual estimates (SIE) method. This effect can then be used to correct for the influence impurities on the realization of the temperature fixed point.

Yaokulbodee, C.; Norranim, U.; Widiatmo, J. V.; Yamazawa, K.; Tamba, J.

2010-09-01

213

Terrestrial concentrator solar cell module  

SciTech Connect

This patent describes a solar cell module having a plurality of discrete cell units wherein each cell unit constitutes a tandem cell comprising an upper cell of a first semiconductive material and a lower cell of a second semiconductive material. It comprises a housing having a base and an upper portion; primary outer lens elements supported by the housing upper portion; a secondary radiant energy concentrating element associated with each primary lens element for protecting the carrier tape against incident light; each of the solar cell units being thermally coupled to the base; and parallel spaced strips of conductive material carried by the tape with means for separately connecting the strips to predetermined contact surfaces of the upper and lower cells of each cell unit.

Fraas, L.M.; Mansoori, N.; Kim, N.B.; Avery, J.E.

1992-06-02

214

Comparative in vitro toxicity of seven zinc-salts towards neuronal PC12 cells.  

PubMed

Currently much attention has been given to the neurotoxicity of zinc, yet little is known about the influence of the counterions present. Therefore, we investigated the influence of different Zn(2+)-salts (concentrations range 0.05-0.3 mM) on cell viability, ATP and glutathione concentration and caspase activation in differentiated PC12 cells as a model for neuronal cells. Generally, at concentrations of 0.05 mM most Zn(2+)-salts were not cytotoxic except for zinc-citrate. At concentrations between 0.1 and 0.3 mM Zn(2+) a significant decrease in GSH and ATP levels preceded cell death induced by all salts, except of zinc-histidinate. Zinc-citrate and zinc-sulphate turned out to be the most toxic salts particularly at low concentrations. Analyses of caspase 3/7 activity showed that dependent on the concentration and the type of the salt used cell death may show more or less signs of both, necrosis and apoptosis. Interestingly, the uptake of Zn(2+) from zinc-sulphate and zinc-citrate was significantly higher than that of other salts, implicating a correlation between uptake and toxicity. In conclusion, Zn(2+)-salts could be divided into three categories with high (zinc-citrate, zinc-sulphate), moderate (zinc-orotate, zinc-acetate, zinc-chloride(,) zinc-gluconate) and low cytotoxicity (zinc-histidinate). PMID:19306923

Pavlica, Sanja; Gaunitz, Frank; Gebhardt, Rolf

2009-03-21

215

Regulation of T cell receptor signaling by activation-induced zinc influx  

PubMed Central

Zinc is a trace element that is essential for innate and adaptive immune responses. In addition to being a structural element of many proteins, zinc also functions as a neurotransmitter and an intracellular messenger. Temporal or spatial changes in bioavailable zinc may influence the activity of several enzymes, including kinases and phosphatases. We provide evidence that zinc functions as an ionic signaling molecule after T cell activation. Cytoplasmic zinc concentrations increased within 1 min after T cell receptor (TCR) triggering, in particular in the subsynaptic compartment. The increase depended on the extracellular zinc concentrations and was inhibited by silencing zinc transporter Zip6. Increased zinc influx reduced the recruitment of SHP-1 to the TCR activation complex, augmented ZAP70 phosphorylation and sustained calcium influx. By calibrating TCR activation thresholds, increased extracellular zinc bioavailability facilitated the induction of T cell proliferative responses to suboptimal stimuli.

Yu, Mingcan; Lee, Won-Woo; Tomar, Deepak; Pryshchep, Sergey; Czesnikiewicz-Guzik, Marta; Lamar, David L.; Li, Guangjin; Singh, Karnail; Tian, Lu; Weyand, Cornelia M.

2011-01-01

216

Effect of zinc on haemoglobin binding by red blood cell membranes  

Microsoft Academic Search

RESULTS of recent studies in our laboratory have suggested that zinc plays an important role in sickle cell anaemia. A significant proportion of sickle cell patients are zinc deficient1. Zinc binds to haemoglobin and increases oxygen affinity2,3. Sickle cells treated in vitro with zinc show markedly improved filterability at concentrations too low to be explained on an oxygen affinity basis4,

Sumitra Dash; George J. Brewer; Fred J. Oelshlegel

1974-01-01

217

Surface-passivated GaAsP single-nanowire solar cells exceeding 10% efficiency grown on silicon  

NASA Astrophysics Data System (ADS)

Continued development of high-efficiency multi-junction solar cells requires growth of lattice-mismatched materials. Today, the need for lattice matching both restricts the bandgap combinations available for multi-junctions solar cells and prohibits monolithic integration of high-efficiency III-V materials with low-cost silicon solar cells. The use of III-V nanowires is the only known method for circumventing this lattice-matching constraint, and therefore it is necessary to develop growth of nanowires with bandgaps >1.4?eV. Here we present the first gold-free gallium arsenide phosphide nanowires grown on silicon by means of direct epitaxial growth. We demonstrate that their bandgap can be controlled during growth and fabricate core-shell nanowire solar cells. We further demonstrate that surface passivation is of crucial importance to reach high efficiencies, and present a record efficiency of 10.2% for a core-shell single-nanowire solar cell.

Holm, Jeppe V.; Jørgensen, Henrik I.; Krogstrup, Peter; Nygård, Jesper; Liu, Huiyun; Aagesen, Martin

2013-02-01

218

Interdigitated back contact solar cells  

NASA Astrophysics Data System (ADS)

The interdigitated back contact solar cell (IBC cell) was shown to possess a number of advantages for silicon solar cells, which operate at high concentration. A detailed discussion of the factors which need to be considered in the analysis of semiconducting devices which utilize heavily doped regions such as those which are found in solar cells in both the emitter and in the back surface field regions is given. This discussion covers the questions of: how to handle degeneracy, how to compute carrier concentrations in the absence of knowledge of the details of the band structure under heavily doped conditions, and how to reconcile the usual interpretation of heavy doping as a rigid shift of the bands with the band tailing and impurity level conduction models. It also discusses the reasons for the observed discrepancies between various experimental measurements of bandgap narrowing.

Lundstrom, M. S.; Schwartz, R. J.

1980-08-01

219

Lithium counterdoped silicon solar cell  

SciTech Connect

The resistance to radiation damage of an n(+)p boron doped silicon solar cell is improved by lithium counterdoping. Even though lithium is an n-dopant in silicon, the lithium is introduced in small enough quantities so that the cell base remains p-type. The lithium is introduced into the solar cell wafer by implantation of lithium ions whose energy is about 50 keV. After this lithium implantation, the wafer is annealed in a nitrogen atmosphere at 375 C for two hours. NASA

Weinberg, I.; Brandhorst, H.W., Jr.

1984-11-01

220

Lithium Counterdoped Silicon Solar Cell.  

National Technical Information Service (NTIS)

The resistance to radiation damage of an n(+)p boron doped silicon solar cell is improved by lithium counterdoping. Even though lithium is an n-dopant in silicon, the lithium is introduced in small enough quantities so that the cell base remains p-type. T...

I. Weinberg H. W. Brandhorst

1984-01-01

221

Functions of zinc in signaling, proliferation and differentiation of mammalian cells  

Microsoft Academic Search

Zinc is essential for cell proliferation and differentiation, especially for the regulation of DNA synthesis and mitosis. On the molecular level, it is a structural constituent of a great number of proteins, including enzymes of cellular signaling pathways and transcription factors. Zinc homeostasis in eukaryotic cells is controlled on the levels of uptake, intracellular sequestration in zinc storing vesicles (`zincosomes'),

Detmar Beyersmann; Hajo Haase

2001-01-01

222

A study of rechargeable zinc electrodes for alkaline cells requiring anodic limitation  

Microsoft Academic Search

Problems associated with the cyclic operation of zinc electrodes in rechargeable alkaline cells for which anodic limitation is required are investigated. Experiments were conducted to determine the influence of electrolyte additives and cell construction on the capacity loss of limited zinc electrodes during cycling; current-voltage diagrams for zinc electrodes within the potential range of passivation and of hydrogen evolution were

L. Binder; W. Odar; K. Kordesch

1981-01-01

223

Photon upconversion for thin film solar cells  

Microsoft Academic Search

In this research one of the many possible methods to increase the efficiency of solar cells is described. The method investigated is based on adapting the solar light in such a way that the solar cell can convert more light into electricity. The part of the solar spectrum that is adapted is the part that cannot be absorbed by the

J. de Wild

2012-01-01

224

Investigation of Sustained Arc under Solar Cell  

Microsoft Academic Search

We have so far studied the sustained arc between solar array strings using solar array coupons. The solar cells are connected electrically in series by interconnectors. The interconnector is conductor and is weld at both backside and top of cells. The solar array paddle undergoes the mechanical stress due to thermal cycles in orbit. This stress may cause the separation

Kazuhiro Toyoda; Mengu Cho; Shirou Kawakita; Masato Takahashi

2010-01-01

225

Solar thermal, decomposition kinetics of zinc sulfate at high heating rates  

SciTech Connect

This paper describes the experimental and analytical methods required to study decomposition of zinc sulfate in a simulated solar environment. Experiments were conducted at sample heating rates greater than 2K/s and temperatures in excess of 1400 K in a specially designed thermogravimetric system which employed a 30-kW/sub e//2-kW/sub th/ downward-facing beam, arc-image furnace. The zinc sulfate decomposition took place almost exclusively through the high-temperature ZnSO/sub 4/..beta.. phase under experimental conditions of this study. The kinetic parameters were determined from the thermogravimetric data by using a nonlinear least-squares optimization algorithm. An apparent activation energy, E, between 210 and 250 kJ/mol and an apparent reaction order, n, between 0 and 0.3 were obtained for ..beta..-phase ZnSO/sub 4/ decomposition reaction. The comparison of these results with those from lower temperature and lower heating rate zinc sulfate decomposition tends to suggest a change in reaction mechanism at the high heating rates expected in a concentrated solar environment.

Tabatabaie-Raissi, A.; Narayan, R.; Mok, W.S.L.; Antal, M.J. Jr.

1989-03-01

226

Performance of porous plastic separators in zinc/bromine cells  

NASA Astrophysics Data System (ADS)

Bromine transport through various acetone-extracted microporous plastic materials is studied with attention given to their use as separators in zinc/bromine cells. Given the porosity and tortuosity of the materials, the samples that were acetone-extracted and then either air-dried or hot-water-quenched showed equivalent thicknesses were far less than would be expected. The measured faradaic efficiencies of cells are in good agreement with those calculated from the bromine transport properties of the chosen separators.

Cathro, K. J.; Constable, D. C.; Hoobin, P. M.

1988-01-01

227

A validated mathematical model for a zinc electrowinning cell  

Microsoft Academic Search

A set of (95) equations forming a dynamic, nonlinear model of an industrial pilot-plant scale zinc electrowinning cell fed with high purity electrolyte is presented. Only the solution of the steady-state model is considered in this paper. Values for unknown model parameters have either been obtained from the literature or else estimated using experimental data taken from the pilot-plant cell.

G. W. Barton; A. C. Scott

1992-01-01

228

Life testing of secondary silver-zinc cells  

Microsoft Academic Search

Testing on a variety of secondary silver-zinc (Ag-Zn) cells has been in progress at the Marshall Space Flight Center (MSFC) for over six years. The latest test involves a 350-Ah cell design that has been cycled at 10 C for 16 months. This design has achieved over 7200 low-earth-orbit (LEO) cycles as well as 17 deep discharges at an 85

Jeffrey C. Brewer; Rajiv Doreswamy

1991-01-01

229

Development of concentrator solar cells  

SciTech Connect

A limited pilot production run on PESC silicon solar cells for use at high concentrations (200 to 400 suns) is summarized. The front contact design of the cells was modified for operation without prismatic covers. The original objective of the contract was to systematically complete a process consolidation phase, in which all the, process improvements developed during the contract would be combined in a pilot production run. This pilot run was going to provide, a basis for estimating cell costs when produced at high throughput. Because of DOE funding limitations, the Photovoltaic Concentrator Initiative is on hold, and Applied Solar`s contract was operated at a low level of effort for most of 1993. The results obtained from the reduced scope pilot run showed the effects of discontinuous process optimization and characterization. However, the run provided valuable insight into the technical areas that can be optimized to achieve the original goals of the contract.

Not Available

1994-08-01

230

Silicon concentrator solar cell research  

SciTech Connect

This report describes work conducted between December 1990 and May 1992 continuing research on silicon concentrator solar cells. The objectives of the work were to improve the performance of high-efficiency cells upon p-type substrates, to investigate the ultraviolet stability of such cells, to develop concentrator cells based on n-type substrates, and to transfer technology to appropriate commercial environments. Key results include the identification of contact resistance between boron-defused areas and rear aluminum as the source of anomalously large series resistance in both p- and n-type cells. A major achievement of the present project was the successful transfer of cell technology to both Applied Solar Energy Corporation and Solarex Corporation.

Green, M.A.; Zhao, J.; Wang, A.; Dai, X.; Milne, A.; Cai, S.; Aberle, A.; Wenham, S.R. [Univ. of New South Wales, Kensington, NSW (AU). Centre for Photovoltaic Devices and Systems

1993-06-01

231

Stray thermal influences in zinc fixed-point cells  

NASA Astrophysics Data System (ADS)

The influence of thermal effects is a major uncertainty contribution to the calibration of Standard Platinum Resistance Thermometers (SPRTs) in fixed-point cells. Axial heat losses strongly depend on the fixed-point temperature, constructional details of cells and SPRTs and the resulting heat transfer between cell, thermometer, furnace and environment. At the zinc point contributions by heat conduction and thermal radiation must be considered. Although the measurement of temperature gradients in the re-entrant well of a fixed-point cell provides very important information about the influence of axial heat losses, further investigations are required for a reliable estimate of the resulting uncertainty contribution. It is shown that specific modifications of a zinc fixed-point cell, following generally accepted principles, may result in systematic deviations of the measured fixed-point temperatures larger than typically stated in the uncertainty budget of National Metrology Institutes (NMIs). The underlying heat transport processes are investigated and the consequences for the construction of zinc cells are discussed.

Rudtsch, S.; Aulich, A.; Monte, C.

2013-09-01

232

TRPM3 channels provide a regulated influx pathway for zinc in pancreatic beta cells  

Microsoft Academic Search

Zinc is stored in insulin-containing dense core vesicles of pancreatic ?-cells where it forms crystals together with insulin\\u000a and calcium ions. Zinc ions are therefore released together with insulin upon exocytosis of these vesicles. Consequently,\\u000a pancreatic ?-cells need to take up large amounts of zinc from the extracellular space across their plasma membrane. The pathways\\u000a for zinc uptake are only

Thomas F. J. Wagner; Anna Drews; Sabine Loch; Florian Mohr; Stephan E. Philipp; Sachar Lambert; Johannes Oberwinkler

2010-01-01

233

New methods for solar cells measurement by LED solar simulator  

Microsoft Academic Search

A solar simulator for solar cells is an important tool to measure their performance. At present, xenon and halogen lamp is used at most laboratories. It is considerably accurate, but the facility is so large and so expensive. Therefore, a solar simulator using LED (light-emitting diode) lamps is proposed, that is low-cost and portable, and was invented to its capability.

S. Kohraku; K. Kurokawa

2003-01-01

234

Solar cell array  

Microsoft Academic Search

An array of photovoltaic cells in a back wall-type configuration supported by a rigid transparent vitreous substrate, such as glass, for admitting incident radiation to the cells is described. A plurality of cells are interconnected into a desired electrical configuration by one or more layers of electrically conducting materials which overlie the entire heterojunction of each cell to minimize the

J. F. Jordan; C. M. Lampkin

1982-01-01

235

Solar cell array  

Microsoft Academic Search

An array of photovoltaic cells in a back wall-type configuration supported by a rigid transparent vitreous substrate, such as glass, for admitting incident radiation to the cells is described. A plurality of cells are interconnected into a desired electrical configuration by one or more layers of electrically conducting materials which overlie substantially the entire heterojunction of each cell to minimize

J. F. Jordan; C. M. Lampkin

1981-01-01

236

Solar thermal decomposition of zinc oxide: an initial investigation of the recombination reaction in the temperature range 1100– 1250 K  

Microsoft Academic Search

We present an experimental and theoretical study that explores the zinc vapour and O2 reaction under laminar flow conditions similar to those that may exist at the exit of a high temperature solar reactor used to decompose ZnO(s). The zinc vapour and O2 reaction was experimentally studied in an electrically heated tubular furnace. A finite difference mass transfer model for

M. Keunecke; A. Meier; R. Palumbo

2004-01-01

237

Key Physical Mechanisms in Nanostructured Solar Cells  

SciTech Connect

The objective of the project was to study both theoretically and experimentally the excitation, recombination and transport properties required for nanostructured solar cells to deliver energy conversion efficiencies well in excess of conventional limits. These objectives were met by concentrating on three key areas, namely, investigation of physical mechanisms present in nanostructured solar cells, characterization of loss mechanisms in nanostructured solar cells and determining the properties required of nanostructured solar cells in order to achieve high efficiency and the design implications.

Dr Stephan Bremner

2010-07-21

238

Titania solar cells: new photovoltaic technology  

Microsoft Academic Search

Titania solar cells are a new type of photovoltaic device invented by Professor Michael Grätzel at Ecole Polytechnique Federale de Lausanne (Switzerland). Titania solar cells convert sunlight directly into electricity through a process similar to photosynthesis. It has performance advantages over other solar cells, which include the ability to perform well in low light and shade, and to perform consistently

George Phani; Gavin Tulloch; David Vittorio; Igor Skryabin

2001-01-01

239

Method of fabricating solar cell modules  

Microsoft Academic Search

The solar cell module of this invention is fabricated by placing an array of solar cells in a suitable mold having a bottom surface, an entry port and an exit port. A light transparent superstrate effectively serves as the top for the mold and is placed over the array of solar cells in the mold. The superstrate is spaced from

W. B. Andrulitis; W. T. Kurth; S. G. Miles

1980-01-01

240

Concentrator solar cell array module  

Microsoft Academic Search

A concentrator solar cell array module is described having a metallic heat sink with a planar mounting surface. A semiconductor spacer is provided. The semiconductor spacer is provided with a layer of insulating material in the form of silicon oxide. The silicon oxide surface is secured to the mounting surface of the heat sink by a thermally conductive adhesive. A

R. M. Diamond; K. S. Ling; A. G. Winterer

1979-01-01

241

Periodic light coupler gratings in amorphous thin film solar cells  

SciTech Connect

Efficient light trapping structures for amorphous hydrogenated silicon (a-Si:H) solar cells have been realized using periodically structured aluminum doped zinc oxide (ZnO:Al) with periods between 390 and 980 nm as a transparent front contact. Atomic force microscopy, optical reflection, and diffraction efficiency measurements were applied to characterize solar cells deposited on such gratings. A simple formula for the threshold wavelength of total internal reflection is derived. Periodic light coupler gratings reduce the reflectance to a value below 10% in the wavelength range of 400{endash}800 nm which is comparable to cells with an optimized statistical texture. Diffraction efficiency measurements and theoretical considerations indicate that a combination of transmission and reflection gratings contribute to the observed reduction of the reflectance. {copyright} 2001 American Institute of Physics.

Eisele, C.; Nebel, C. E.; Stutzmann, M.

2001-06-15

242

Impedance of silver oxide-zinc cells  

Microsoft Academic Search

Over 100 sealed AgO-Zn cells were subjected to prolonged periods of storage over a range of temperatures and storage modes including open circuit, trickle charge, and float charge. Impedances of these cells were monitored throughout, and at the end of the storage period their transient voltage characteristics were observed at the onset of discharge. Results revealed that the impedances of

H. A. Frank; W. L. Long; A. A. Uchiyama

1976-01-01

243

Alterations in protein kinase C activity and processing during zinc-deficiency-induced cell death  

PubMed Central

Protein kinases C (PKCs) are a family of serine/threonine kinases that are critical for signal transduction pathways involved in growth, differentiation and cell death. All PKC isoforms have four conserved domains, C1–C4. The C1 domain contains cysteine-rich finger-like motifs, which bind two zinc atoms. The zinc-finger motifs modulate diacylglycerol binding; thus, intracellular zinc concentrations could influence the activity and localization of PKC family members. 3T3 cells were cultured in zinc-deficient or zinc-supplemented medium for up to 32 h. Cells cultured in zinc-deficient medium had decreased zinc content, lowered cytosolic classical PKC activity, increased caspase-3 processing and activity, and reduced cell number. Zinc-deficient cytosols had decreased activity and expression levels of PKC-?, whereas PKC-? phosphorylation was not altered. Inhibition of PKC-? with Gö6976 had no effect on cell number in the zinc-deficient group. Proteolysis of the novel PKC family member, PKC-?, to its 40-kDa catalytic fragment occurred in cells cultured in the zinc-deficient medium. Occurrence of the PKC-? fragment in mitochondria was co-incident with caspase-3 activation. Addition of the PKC-? inhibitor, rottlerin, or zinc to deficient medium reduced or eliminated proteolysis of PKC-?, activated caspase-3 and restored cell number. Inhibition of caspase-3 processing by Z-DQMD-FMK (Z-Asp-Gln-Met-Asp-fluoromethylketone) did not restore cell number in the zinc-deficient group, but resulted in processing of full-length PKC-? to a 56-kDa fragment. These results support the concept that intracellular zinc concentrations influence PKC activity and processing, and that zinc-deficiency-induced apoptosis occurs in part through PKC-dependent pathways.

2004-01-01

244

A novel chlorophyll solar cell  

NASA Astrophysics Data System (ADS)

The photosynthetic process is reviewed in order to produce a design for a chlorophyll solar cell. In a leaf, antenna chlorophyll absorbs light energy and conducts it to an energy trap composed of a protein and two chlorophyll molecules, which perform the oxidation-reduction chemistry. The redox potential of the trap changes from 0.4 to -0.6 V, which is sufficient to reduce nearby molecules with redox potentials in that range. The reduction occurs by transfer of an electron, and a chlorophyll solar cell would direct the transferred electron to a current carrier. Chlorophyll antenna and traps are placed on a metallic support immersed in an electron acceptor solution, and resulting electrons from exposure to light are gathered by a metallic current collector. Spinach chlorophyll extracted, purified, and applied in a cell featuring a Pt collector and an octane water emulsion resulted in intensity independent voltages.

Ludlow, J. C.

245

Mixed ternary heterojunction solar cell  

DOEpatents

A thin film heterojunction solar cell and a method of making it has a p-type layer of mixed ternary I-III-VI.sub.2 semiconductor material in contact with an n-type layer of mixed binary II-VI semiconductor material. The p-type semiconductor material includes a low resistivity copper-rich region adjacent the back metal contact of the cell and a composition gradient providing a minority carrier mirror that improves the photovoltaic performance of the cell. The p-type semiconductor material preferably is CuInGaSe.sub.2 or CuIn(SSe).sub.2.

Chen, Wen S. (Seattle, WA); Stewart, John M. (Seattle, WA)

1992-08-25

246

Solar cell calibration by balloon flight  

Microsoft Academic Search

An overview of the manufacture and calibration by balloon flight of primary standard solar batteries is presented as follows. Primary standard solar battery cells of micro N electrode Back Surface Reflector (BSR) and micro N electrode Back Surface Field and Reflector (BSFR) type were produced, and primary solar battery modules of both types were assembled each with four cells selected

Sumio Matsuda; Takashi Tamura; Masato Uesugi

1992-01-01

247

A mathematical model of a zinc/bromine flow cell  

SciTech Connect

A mathematical model is presented for a zinc/bromine flow cell. The model includes a thin porous layer on the bromine electrode and a porous separator. The independent parameters of the porous layer are defined, and their effect on cell performance during charge and discharge is investigated. The dependence of the round trip energy efficiency on the thickness of the porous layer and mode of discharge is presented. The predictions of the model show that a maximum round trip energy efficiency of 70% should be possible under the design conditions considered.

Evans, T.I.; White, R.E.

1987-04-01

248

Zinc at Cytotoxic Concentrations Affects Posttranscriptional Events of Gene Expression in Cancer Cells  

PubMed Central

Zinc at cytotoxic concentrations has been shown to regulate gene transcription in cancer cells, though zinc's involvement in posttranscriptional regulation is less characterized. In this study, we investigated the involvement of cytotoxic zinc in the posttranscriptional steps of gene expression. Clioquinol, a well-established zinc ionophore, was used to raise intracellular zinc to reported cytotoxic levels. The MCF-7 human cancer cell line was applied as a cell model system. Several parameters were used as indictors of posttranscriptional regulation, including p-body formation, microRNA profiling, expression level of proteins known to regulate mRNA degradation, microRNA processing, and protein translation. p-body formation was observed in MCF-7 cells using several molecules known as p-body components. Clioquinol plus zinc enhanced p-body assembly in MCF-7 cells. This enhancement was zinc-specific and could be blocked by a high affinity zinc chelator. The enhancement does not seem to be due to a stress response, as paclitaxel, a commonly used chemotherapeutic, did not cause enhanced p-body formation at a highly cytotoxic concentration. microRNA profiling indicated that clioquinol plus zinc globally down-regulates microRNA expression in this model system, which is associated with the reduced expression of Dicer, an enzyme key to microRNA maturation, and Ago2, a protein essential for microRNA stability. This study demonstrates that ionophoric zinc can induce cytotoxicity in cancer cells by globally regulating posttranscriptional events.

Zheng, Jie; Zhang, Xiao-Xi; Yu, Haijun; Taggart, Jori E.; Ding, Wei-Qun

2012-01-01

249

Solar cell junction processing system  

Microsoft Academic Search

An integrated system and process for the continuous formation of p-n junctions in solar cells in a cost-effective manner and under computer control. The integrated system essentially comprises an ion beam implanter, an electron beam annealer and a combination vacuum lock-and-wafer transport system, all disposed within a unitary housing maintained under a common vacuum environment. The integrated system employs no

A. J. Armini; R. G. Little

1982-01-01

250

Fabrication and testing of sealed silver--zinc cells. Final report  

Microsoft Academic Search

A number of Type HS40-7 sealed silver--zinc cells and experimental 40-Ah sealed silver--zinc cells were fabricated. Cells of each experimental group contained one variation from the standard configuration (HS40-7) cell. Cells from each of five experimental cell groups and cells of the standard configuration were tested to characterize voltage and capacity performance at various discharge rates. The test cells were

Donnel; C. P. I

1976-01-01

251

New reactions involving the oxidative O-, N-, and C-phosphorylation of organic compounds by phosphorus and phosphides in the presence of metal complexes  

NASA Astrophysics Data System (ADS)

The mechanisms of new catalytic reactions leading to the formation of di-, and tri-alkyl phosphates, di- and tri-alkyl phosphites, phosphoramidites, phosphazenes, phosphines, and phosphine oxides from hydrogen, copper, and zinc phosphides and white and red phosphorus are analysed. The mechanisms of the activation of the reactants by metal complexes and of the reactions involving the oxidative P-O, P-N, and P-C coupling of organic compounds to phosphorus and phosphides are considered. The bibliography includes 124 references.

Dorfman, Ya A.; Aleshkova, M. M.; Polimbetova, G. S.; Levina, L. V.; Petrova, T. V.; Abdreimova, R. R.; Doroshkevich, D. M.

1993-09-01

252

Current status of silicon solar cell technology  

Microsoft Academic Search

In quest of higher efficiency, major progress has occurred in solar cell technology during the last five years. In this period cell efficiency has climbed about 50 percent. Technical approaches leading to increased output include back surface fields (n+-p-p+structures), shallow junctions, improved antireflection coatings, surface texturizing, and fine grid patterns on the cell surface. The status of current solar cell

H. W. Jr

1975-01-01

253

Silicon concentrator solar cell development  

NASA Astrophysics Data System (ADS)

This project involved the development and supply of 550 silicon concentrator solar cells for use in prototype point-focus concentrator modules. The cells were to have a designed illumination area of 12.5 by 12.5 mm and to be designed for use with prismatic covers at a geometric concentration ratio of 200X. The target efficiency of 24 percent was comfortably exceeded, with efficiencies as high as 25.2 percent reached in the designed concentration ratio range. A combined lens/cell efficiency of 24.4 percent was measured at Sandia using a cell supplied during this project and a point focus Fresnel lens. Subsequently, a peak module efficiency of 20.3 percent was achieved at Sandia using 12 cells and lenses. This is believed to be the first photovoltaic module to surpass the 20 percent efficiency milestone.

Green, Martin A.; Jianhua, Zhao; Aihua, Wang; Blakers, A. W.

1990-05-01

254

Free zinc inhibits transport of vitamin C in differentiated HL60 cells during respiratory burst  

Microsoft Academic Search

Zinc is an essential trace element for the immune system. It is known to be essential for highly proliferating cells, especially for cells of the immune system. However, zinc and other divalent cations are known to inhibit the human neutrophilic NADPH oxidase. Differentiated HL-60 cells were found to accumulate large quantities of vitamin C (ascorbate) after activation of the NADPH

Hildegard Laggner; Katharina Phillipp; Hans Goldenberg

2006-01-01

255

The cytotoxic effects of titanium oxide and zinc oxide nanoparticles oh Human Cervical Adenocarcinoma cell membranes  

NASA Astrophysics Data System (ADS)

The importance of titanium dioxide (TiO2) and zinc oxide (ZnO), inorganic metal oxides nanoparticles (NPs) stems from their ubiquitous applications in personal care products, solar cells and food whitening agents. Hence, these NPs come in direct contact with the skin, digestive tracts and are absorbed into human tissues. Currently, TiO2 and ZnO are considered safe commercial ingredients by the material safety data sheets with no reported evidence of carcinogenicity or ecotoxicity, and do not classify either NP as a toxic substance. This study examined the direct effects of TiO2 and ZnO on HeLa cells, a human cervical adenocarcinonma cell line, and their membrane mechanics. The whole cell patch-clamp technique was used in addition to immunohistochemistry staining, TEM and atomic force microscopy (AFM). Additionally, we examined the effects of dexamethasone (DXM), a glucocorticoid steroid known to have an effect on cell membrane mechanics. Overall, TiO2 and ZnO seemed to have an adverse effect on cell membrane mechanics by effecting cell proliferation, altering cellular structure, decreasing cell-cell adhesion, activating existing ion channels, increasing membrane permeability, and possibly disrupting cell signaling.

Mironava, Tatsiana; Applebaum, Ariella; Applebaum, Eliana; Guterman, Shoshana; Applebaum, Kayla; Grossman, Daniel; Gordon, Chris; Brink, Peter; Wang, H. Z.; Rafailovich, Miriam

2013-03-01

256

A global view of the selectivity of zinc deprivation and excess on genes expressed in human THP-1 mononuclear cells  

PubMed Central

Among the micronutrients required by humans, zinc has particularly divergent modes of action. cDNA microarray and quantitative PCR technologies were used to investigate the zinc responsiveness of known genes that influence zinc homeostasis and to identify, through global screening, genes that may relate to phenotypic outcomes of altered dietary zinc intake. Human monocytic/macrophage THP-1 cells were either acutely zinc depleted, using a cell-permeable zinc-specific chelator, or were supplemented with zinc to alter intracellular zinc concentrations. Initially, genes associated with zinc homeostasis were evaluated by quantitative PCR to establish ranges for fold changes in transcript abundance that might be expected with global screening. Zinc transporter-1 and zinc transporter-7 expression increased when cellular zinc increased, whereas Zip-2 expression, the most zinc-responsive gene examined, was markedly increased by zinc depletion. Microarrays composed of ?22,000 elements were used to identify those genes responsive to either zinc depletion, zinc supplementation, or both conditions. Hierarchal clustering and ANOVA revealed that ?5% or 1,045 genes were zinc responsive. Further sorting based on this pattern of the zinc responsiveness of these genes into seven groups revealed that 104 genes were linearly zinc responsive in a positive mode (i.e., increased expression as cellular zinc increases) and 86 genes that were linearly zinc responsive in a negative mode (i.e., decreased expression as cellular zinc increases). Expression of some genes was responsive to only zinc depletion or supplementation. Categorization by function revealed numerous genes needed for host defense were among those identified as zinc responsive, including cytokine receptors and genes associated with amplification of the Th1 immune response.

Cousins, Robert J.; Blanchard, Raymond K.; Popp, Michael P.; Liu, Li; Cao, Jay; Moore, J. Bernadette; Green, Calvert L.

2003-01-01

257

Development of Single Cell Protectors for Sealed Silver-Zinc Cells, Phase 1.  

National Technical Information Service (NTIS)

A single cell protector (SCP) assembly capable of protecting a single silver-zinc (Ag Zn) battery cell was designed, fabricated, and tested. The SCP provides cell-level protection against overcharge and overdischarge by a bypass circuit. The bypass circui...

B. Murray J. W. Lear M. S. Imamura R. L. Donovan

1976-01-01

258

Cell type-specific action of seizure-induced intracellular zinc accumulation in the rat hippocampus  

PubMed Central

Increased levels of intracellular zinc have been implicated in neuronal cell death in ischaemia, epilepsy and traumatic brain damage. However, decreases in zinc levels also lead to increased neuronal death and lowered seizure threshold. In the present study we investigated the physiological role of zinc in neurodegeneration and protection following epileptic seizures. Cells located in the strata oriens and lucidum of the CA3 region accumulated high concentrations of zinc and died. A decrease in zinc level could prevent the death of these neurones after seizures. Most of these cells were GABAergic interneurones. In contrast, neurones in the CA3 pyramidal cell layer accumulated moderate amounts of zinc and survived. Zinc chelation led to an increase in the mortality rate of these cells. Furthermore, in these cells low concentrations of intracellular zinc activated Akt (protein kinase B), thus providing protection against neurodegeneration. These results demonstrate that intracellularly accumulated zinc can be neurotoxic or neuroprotective depending on its concentration. This dual action is cell type specific.

Cote, Amelie; Chiasson, Marilou; Peralta, Modesto R; Lafortune, Kathleen; Pellegrini, Luca; Toth, Katalin

2005-01-01

259

Screen-printable silver pastes with metallic nano-zinc and nano-zinc alloys for crystalline silicon photovoltaic cells.  

PubMed

Silver metallization pastes for crystalline silicon PV cells containing nanosized metallic zinc were found to be superior to commercial pastes containing micrometer-sized metallic zinc and micrometer sized zinc oxide in terms of efficiency and firing window. Efficiency performance decreases as the size of the particles increases: nano-Zn > 3.6 ?m Zn > 4.4 ?m Zn. Advanced electron microscopy techniques were used to investigate the interfacial microstructure between the front-side contact and the Si emitter of nanosized zinc additive based cells fired at temperatures from below to above optimal. These microstructural observations confirmed the possibility of a tunneling mechanism of current flow (a "nano-Ag colloid assisted tunneling" model) in the absence of Ag crystallites. Contact resistance maps were used to guide sampling, leading to a better understanding of the relationship between microstructure and contact resistance. Low contact resistance and higher cell efficiency, especially at under- and overfiring temperature conditions, are due to more uniform silicon nitride etching obtained through the use of nanosized metallic zinc additives. PMID:21291277

Ionkin, Alex S; Fish, Brian M; Li, Zhigang Rick; Lewittes, Mark; Soper, Paul D; Pepin, John G; Carroll, Alan F

2011-02-03

260

Regeneration of T-Cell Helper Function in Zinc-Deficient Adult Mice  

Microsoft Academic Search

Diets deficient in zinc cause rapid atrophy of the thymus and loss of T-cell helper function in the young adult A\\/J mouse. Because zinc deficiency, as well as other nutritional deficiencies, causes extensive damage to the immune system, the question arose as to whether zinc-deficient mice could repair the thymus and fully regenerate T-cell helper function if returned to diets

Pamela J. Fraker; Paula Depasquale-Jardieu; Craig M. Zwicki; Richard W. Luecke

1978-01-01

261

Investigation of Sustained Arc under Solar Cell  

NASA Astrophysics Data System (ADS)

We have so far studied the sustained arc between solar array strings using solar array coupons. The solar cells are connected electrically in series by interconnectors. The interconnector is conductor and is weld at both backside and top of cells. The solar array paddle undergoes the mechanical stress due to thermal cycles in orbit. This stress may cause the separation of interconnector welding backside of cells. If the interconnector is separated from the cell, the string circuit is opened. However solar cells can generate voltage. If the separated interconnector attached to the cell again, the current can flow. If the path between interconnector and cell is formed by insulated adhesive, sustained arc can occur between the separated interconnector and cell. In this paper, the sustained arc between interconnector and cells was investigated experimentally.

Toyoda, Kazuhiro; Cho, Mengu; Kawakita, Shirou; Takahashi, Masato

262

Pleural effusion in aluminum phosphide poisoning  

PubMed Central

Aluminium phosphide (ALP) is a common agrochemical pesticide poisoning with high mortality rate. Primary manifestations are due to myocardial and gastrointestinal involvement. Pleural effusion in ALP poisoning is occasionally reported. We report a case of pleural effusion that developed after ALP ingestion and resolved along with recovery from poisoning.

Garg, Kranti; Mohapatra, Prasanta R.; Sodhi, Mandeep K.; Janmeja, Ashok K.

2012-01-01

263

An algebraic model for a zinc/bromine flow cell  

NASA Astrophysics Data System (ADS)

An algebraic model for a parallel plate, zinc/bromine flow cell is presented and used to predict various performance quantities, which are compared to those predicted by using previously published differential equation models. The results presented compare well with previous work. The model is based on the concept of using well-mixed zones and linear concentration and potential profiles for the diffusion layers and the separator. The Butler-Volmer equation is used for the electrochemical reactions, and the homogeneous reaction between bromine and bromide is included.

Simpson, G. D.; White, R. E.

1989-08-01

264

Photoelectrochemical reduction of aqueous carbon dioxide on p-type gallium phosphide in liquid junction solar cells  

Microsoft Academic Search

Not Available Bibtex entry for this abstract Preferred format for this abstract (see Preferences) Find Similar Abstracts: Use: Authors Title Keywords (in text query field) Return: Query Results Return items starting with number Query Form Database: Astronomy Physics arXiv e-prints

M. Halmann

1978-01-01

265

Indium phosphide/cadmium sulfide thin-film solar cells. Quarterly technical progress report No. 3, December 1979-April 1980  

SciTech Connect

Thin films (approx. 1 ..mu..m thick) and large grains (approx. 40 x 40 ..mu..m) of InP were epitaxially deposited on low-cost recrystallized CdS (RXCdS) substrates at 280/sup 0/C by planar reactive deposition. At 380/sup 0/C, a 0.4- to 1.0-..mu..m-thick In-Cd-S transition layer between the InP and the RXCdS degrades the quality of the InP epitaxy. However, p-type InP films were prepared at this temperature by Be-doping and capping the entire RXCdS substrate with InP. Large grains of CdTe (approx. 40 ..mu..m) were also deposited on RXCdS substrates at 460/sup 0/C by physical vapor deposition. The grain size of the RXCdS is typically 40 ..mu..m. However, during this period we prepared RXCdS with grains having dimensions up to 300 ..mu..m.

Zanio, K.

1980-06-01

266

Energy Conversion: Nano Solar Cell  

NASA Astrophysics Data System (ADS)

Problems of fossil-fuel-induced climate change have sparked a demand for sustainable energy supply for all sectors of economy. Most laboratories continue to search for new materials and new technique to generate clean energy at affordable cost. Nanotechnology can play a major role in solving the energy problem. The prospect for solar energy using Si-based technology is not encouraging. Si photovoltaics can produce electricity at 20-30 cslash/kWhr with about 25% efficiency. Nanoparticles have a strong capacity to absorb light and generate more electrons for current as discovered in the recent work of organic and dye-sensitized cell. Using cheap preparation technique such as screen-printing and self-assembly growth, organic cells shows a strong potential for commercialization. Thin Films research group at National University Malaysia has been actively involved in these areas, and in this seminar, we will present a review works on nanomaterials for solar cells and particularly on hybrid organic solar cell based on ZnO nanorod arrays. The organic layer consisting of poly[2-methoxy-5-(2-ethylhexyloxy)-1, 4-phenylenevinylene] (MEHPPV) and [6, 6]-phenyl C61-butyric acid 3-ethylthiophene ester (PCBE) was spin-coated on ZnO nanorod arrays. ZnO nanorod arrays were grown on FTO glass substrates which were pre-coated with ZnO nanoparticles using a low temperature chemical solution method. A gold electrode was used as the top contact. The device gave a short circuit current density of 2.49×10-4 mA/cm2 and an open circuit voltage of 0.45 V under illumination of a projector halogen light at 100 mW/cm2.

Yahaya, Muhammad; Yap, Chi Chin; Mat Salleh, Muhamad

2009-09-01

267

Optimization of transparent and reflecting electrodes for amorphous silicon solar cells. Annual subcontract report, April 1, 1994--March 31, 1995  

SciTech Connect

Transparent and reflecting electrodes are important parts of the structure of amorphous silicon solar cells. We report improved methods for depositing zinc oxide, deposition of tin nitride as a potential reflection-enhancing diffusion barrier between the a-Si and back metal electrodes. Highly conductive and transparent fluorine-doped zinc oxide was successfully produced on small areas by atmospheric pressure CVD from a less hazardous zinc precursor, zinc acetylacetonate. The optical properties measured for tin nitride showed that the back-reflection would be decreased if tin nitride were used instead of zinc oxide as a barrier layer over silver on aluminum. Niobium-doped titanium dioxide was produced with high enough electrical conductivity so that normal voltages and fill factors were obtained for a-Si cells made on it.

Gordon, R.G. [Harvard Univ., Cambridge, MA (United States)

1995-10-01

268

Epitaxial thin-film Si solar cells  

Microsoft Academic Search

Most types of thin-film solar cells imply a radical departure from the dominant bulk crystalline Si technology. This is not the case for epitaxial thin-film solar cells. In this technology, a high quality Si layer is deposited epitaxially on a low-cost Si substrate (e.g. cast Upgraded Metallurgical Grade silicon or high-throughput Si ribbons) and processed into a solar cell. This

G. Beaucarne; F. Duerinckx; I. Kuzma; K. Van Nieuwenhuysen; H. J. Kim; J. Poortmans

2006-01-01

269

Bypass diode for a solar cell  

DOEpatents

Bypass diodes for solar cells are described. In one embodiment, a bypass diode for a solar cell includes a substrate of the solar cell. A first conductive region is disposed above the substrate, the first conductive region of a first conductivity type. A second conductive region is disposed on the first conductive region, the second conductive region of a second conductivity type opposite the first conductivity type.

Rim, Seung Bum (Palo Alto, CA); Kim, Taeseok (San Jose, CA); Smith, David D. (Campbell, CA); Cousins, Peter J. (Menlo Park, CA)

2012-03-13

270

New materials for nanocrystal solar cells  

Microsoft Academic Search

New organic and inorganic materials for nanocrystal solar cells are reported with descriptions and basic characterization of their applicability. Brief background is presented regarding the fundamental operation of nanocrystal-polymer solar cells as context for the body of this work. New colloidal nanocrystals synthesized for solar cells include CdTe tetrapods for improved light absorption and electron transport, and Type II core\\/shell

Delia Jane Milliron

2004-01-01

271

Angiotensin II Requires Zinc and Downregulation of the Zinc Transporters ZnT3 and ZnT10 to Induce Senescence of Vascular Smooth Muscle Cells  

PubMed Central

Senescence, a hallmark of mammalian aging, is associated with the onset and progression of cardiovascular disease. Angiotensin II (Ang II) signaling and zinc homeostasis dysfunction are increased with age and are linked to cardiovascular disease, but the relationship among these processes has not been investigated. We used a model of cellular senescence induced by Ang II in vascular smooth muscle cells (VSMCs) to explore the role of zinc in vascular dysfunction. We found that Ang II-induced senescence is a zinc-dependent pathway mediated by the downregulation of the zinc transporters ZnT3 and ZnT10, which work to reduce cytosolic zinc. Zinc mimics Ang II by increasing reactive oxygen species (ROS), activating NADPH oxidase activity and Akt, and by downregulating ZnT3 and ZnT10 and inducing senescence. Zinc increases Ang II-induced senescence, while the zinc chelator TPEN, as well as overexpression of ZnT3 or ZnT10, decreases ROS and prevents senescence. Using HEK293 cells, we found that ZnT10 localizes in recycling endosomes and transports zinc into vesicles to prevent zinc toxicity. Zinc and ZnT3/ZnT10 downregulation induces senescence by decreasing the expression of catalase. Consistently, ZnT3 and ZnT10 downregulation by siRNA increases ROS while downregulation of catalase by siRNA induces senescence. Zinc, siZnT3 and siZnT10 downregulate catalase by a post-transcriptional mechanism mediated by decreased phosphorylation of ERK1/2. These data demonstrate that zinc homeostasis dysfunction by decreased expression of ZnT3 or ZnT10 promotes senescence and that Ang II-induced senescence is a zinc and ROS-dependent process. Our studies suggest that zinc might also affect other ROS-dependent processes induced by Ang II, such as hypertrophy and migration of smooth muscle cells.

Patrushev, Nikolay; Seidel-Rogol, Bonnie; Salazar, Gloria

2012-01-01

272

Interdigitated Back Contact Solar Cells. Annual Report.  

National Technical Information Service (NTIS)

The interdigitated back-contact solar cell (IBC cell) has been shown to possess a number of advantages for silicon solar cells, which operate at high concentration. The purpose of the present program is to support the Sandia Laboratory effort to optimize ...

M. S. Lundstrom R. J. Schwartz

1980-01-01

273

The MIS and MISIM solar cell  

Microsoft Academic Search

The insertion of a very thin insulating layer (less than 20 A) between the metal and the semiconductor of a Schottky solar cell can dramatically improve the open circuit voltage of the cell. The resulting MIS structure is shown to be electronically equivalent to a p-n junction device, provided that minority current flow is dominant. The MISIM solar cell, a

M. A. Green; R. B. Godfrey

1978-01-01

274

Interconnect for electrically connecting solar cells  

SciTech Connect

This paper describes a solar cell array. It comprises: solar cells arranged in an array, each the solar cell having an upper electrical contact and a lower electrical contact; interconnects for electrically connecting the solar cells, each the interconnect comprising: a stress relief part comprised of a single longitudinally extended member having a central portion and first and second end portions defining a planar surface; a first connecting part attached to the upper contact of a respective one of the solar cells; a second connecting part attached to the lower contact of a solar cell adjacent to the respective one of the solar cells; means for joining the first and second connecting parts to respective first and second end portions of the stress relief part such that the central portion of the stress relief part is disposed substantially parallel to adjacent edges of the solar cells which are electrically connected by the interconnect and such that the planar surface defined by the stress relief part extends substantially perpendicularly relative to the top surface of the solar cell array.

Gaddy, E.M.

1991-04-09

275

Very High Efficiency Solar Cell Modules  

SciTech Connect

The Very High Efficiency Solar Cell (VHESC) program is developing integrated optical system - PV modules for portable applications that operate at greater than 50% efficiency. We are integrating the optical design with the solar cell design, and have entered previously unoccupied design space. Our approach is driven by proven quantitative models for the solar cell design, the optical design, and the integration of these designs. Optical systems efficiency with an optical efficiency of 93% and solar cell device results under ideal dichroic splitting optics summing to 42.7 {+-} 2.5% are described.

Barnett, A.; Kirkpatrick, D.; Honsberg, C.; Moore, D.; Wanlass, M.; Emery, K.; Schwartz, R.; Carlson, D.; Bowden, S.; Aiken, D.; Gray, A.; Kurtz, S.; Kazmerski, L., et al

2009-01-01

276

Luminescence radiation spectroscopy of silicon solar cells  

NASA Astrophysics Data System (ADS)

At present there are known many of diagnostic methods of detection large crystal lattice defects of silicon solar cells. This paper deals about results of new potential in to use one of characteristics luminescence radiation for detection defects of solar cells. So polarization spectroscopy of defect in solar cells may be used to fitting characterization of silicon solar cells. And this can lead to understand the electrical properties of defects in silicon solar cells and study of really formation defects. We used extending existing electroluminescence technology about polarization spectroscopy to yield the polarization of luminescence radiation by defect in solar cells. Radiation emitted by the solar cell has a wave character that can interact with the silicon structures or hypothetically thin reflectance layer of solar cells. In our research we can observed the linear partially polarization luminescence light on poly-silicon crack defect. Spectral response of using CCD camera is approximately 300 to 1100 nm. Sinusoid dependence of luminescence intensity on the angle of linear polarization analyzer rotation shown this fact. The degree of polarization depends on the material, in this case the character of defect. Polarized light can be obtained in various ways. This fact opens up for potential next new questions in this widely course of study diagnostics defects silicon solar cells.

Stojan, R.; Van?k, J.; Malý, M.; Gvritishvili, R.; Tománek, P.; Frantík, O.

2013-09-01

277

Plasmonic silicon solar cells: impact of material quality and geometry.  

PubMed

We study n-i-p amorphous silicon solar cells with light-scattering nanoparticles in the back reflector. In one configuration, the particles are fully embedded in the zinc oxide buffer layer; In a second configuration, the particles are placed between the buffer layer and the flat back electrode. We use stencil lithography to produce the same periodic arrangement of the particles and we use the same solar cell structure on top, thus establishing a fair comparison between a novel plasmonic concept and its more traditional counterpart. Both approaches show strong resonances around 700 nm in the external quantum efficiency the position and intensity of which vary strongly with the nanoparticle shape. Moreover, disagreement between simulations and our experimental results suggests that the dielectric data of bulk silver do not correctly represent the reality. A better fit is obtained by introducing a porous interfacial layer between the silver and zinc oxide. Without the interfacial layer, e.g. by improved processing of the nanoparticles, our simulations show that the nanoparticles concept could outperform traditional back reflectors. PMID:24104574

Pahud, Celine; Isabella, Olindo; Naqavi, Ali; Haug, Franz-Josef; Zeman, Miro; Herzig, Hans Peter; Ballif, Christophe

2013-09-01

278

A review of mathematical modelling of the zinc/bromine flow cell and stack of cells  

NASA Astrophysics Data System (ADS)

Macroscopic mathematical models for investigating various aspects of the zinc/bromine cell and stack of cells are reviewed. The general material balance equation for each species, in addition to the general expressions describing both transport in a parallel plate electrochemical reactor and the electrode kinetics, are first given. Partial differential equation models predicting current and potential distributions, an algebraic model including shunt currents and associated energy losses, and ordinary differential equation models predicting energy efficiency of the cell as a function of the state-of-charge are discussed. Microscopic models which describe the initiation and subsequent growth of zinc dendrites are also considered.

Evans, T. I.; White, R. E.

279

Solar cells using quantum funnels.  

PubMed

Colloidal quantum dots offer broad tuning of semiconductor bandstructure via the quantum size effect. Devices involving a sequence of layers comprised of quantum dots selected to have different diameters, and therefore bandgaps, offer the possibility of funneling energy toward an acceptor. Here we report a quantum funnel that efficiently conveys photoelectrons from their point of generation toward an intended electron acceptor. Using this concept we build a solar cell that benefits from enhanced fill factor as a result of this quantum funnel. This concept addresses limitations on transport in soft condensed matter systems and leverages their advantages in large-area optoelectronic devices and systems. PMID:21827197

Kramer, Illan J; Levina, Larissa; Debnath, Ratan; Zhitomirsky, David; Sargent, Edward H

2011-08-11

280

Lithium counterdoped silicon solar cell  

SciTech Connect

A radiation damage resistant solar cell is described comprising a wafer of p-type boron doped silicon having lithium ions implanted therein in small enough quantities such that the wafer remains p-type after lithium addition. The wafer has an n/sup +/ region formed by phosphorus ions implanted therein adjacent to a surface of the wafer, a first electrical contact on the surface adjacent to the n/sup +/ region, and a second electrical contact on an opposite surface of the wafer.

Weinberg, I.; Brandhorst, H.W. Jr.

1986-08-26

281

Improved monolithic tandem solar cell  

DOEpatents

A single-crystal, monolithic, tandem, photovoltaic solar cell is described which includes (a) an InP substrate having upper and lower surfaces, (b) a first photoactive subcell on the upper surf ace of the InP substrate, (c) a second photoactive subcell on the first subcell; and (d) an optically transparent prismatic cover layer over the second subcell. The first photoactive subcell is GaInAsP of defined composition. The second subcell is InP. The two subcells are lattice matched.

Wanlass, M.W.

1991-04-23

282

Investigation of polycrystalline thin film CuInSe2 solar cells based on ZnSe windows  

Microsoft Academic Search

This report concerns studies of CIS solar cells based on ZnSe window layers. ZnSe\\/CIS devices are fabricated by growing ZnSe films by MOCVD onto Siemens CIS and graded absorber substrates. ZnSe films are grown by reacting H2Se with a zinc adduct. ZnSe\\/CIS heterojunctions have been studied by depositing transparent aluminum contacts onto ZnSe. These studies indicate that ZnSe\\/CIS solar cells

L. C. Olsen

1995-01-01

283

High-Efficiency PIN Microcrystalline and Micromorph Thin Film Silicon Solar Cells Deposited on LPCVD Zno Coated Glass Substrates  

Microsoft Academic Search

The authors report on the fabrication of microcrystalline silicon p-i-n solar cells with efficiencies close to 10%, using glass coated with zinc oxide (ZnO) deposited by low pressure chemical vapor deposition (LPCVD). LPCVD front contacts were optimized for p-i-n microcrystalline silicon solar cells by decreasing the free carrier absorption of the layers and increasing the surface roughness. These modifications resulted

J. Bailat; D. Domine; R. Schluchter; J. Steinhauser; S. Fay; F. Freitas; C. Bucher; L. Feitknecht; X. Niquille; T. Tscharner; A. Shah; C. Ballif

2006-01-01

284

Nanosized Zinc Oxide Induces Toxicity in Human Lung Cells  

PubMed Central

Zinc oxide nanoparticles (ZnO-NPs) are increasingly used in sunscreens, biosensors, food additives, pigments, rubber manufacture, and electronic materials. With the wide application of ZnO-NPs, concern has been raised about its unintentional health and environmental impacts. This study investigates the toxic effects of ZnO-NPs in human lung cells. In order to assess toxicity, human lung epithelial cells (L-132) were exposed to dispersion of 50?nm ZnO-NPs at concentrations of 5, 25, 50, and 100??g/mL for 24?h. The toxicity was evaluated by observing changes in cell morphology, cell viability, oxidative stress parameters, DNA damage analysis, and gene expression. Exposure to 50?nm ZnO-NPs at concentrations between 5 and 100??g/mL decreased cell viability in a concentration-dependent manner. Morphological examination revealed cell shrinkage, nuclear condensation, and formation of apoptotic bodies. The oxidative stress parameters revealed significant depletion of GSH level and increase in ROS levels suggesting generation of oxidative stress. ZnO-NPs exposure caused DNA fragmentation demonstrating apoptotic type of cell death. ZnO-NPs increased the expression of metallothionein gene, which is considered as a biomarker in metal-induced toxicity. To summarize, ZnO-NPs cause toxicity in human lung cells possibly through oxidative stress-induced apoptosis.

Sahu, Devashri; Kannan, G. M.; Vijayaraghavan, R.; Anand, T.; Khanum, Farhath

2013-01-01

285

Polyphenol-rich beverages enhance zinc uptake and metallothionein expression in Caco-2 cells.  

PubMed

The effect of red wine (RW), red grape juice (RGJ), green tea (GT), and representative polyphenols on Caco-2 cell (65)Zn uptake was explored. RW, RGJ, and GT enhanced the uptake of zinc from rice matrix. Fractionation of RW revealed that enhancing activity of zinc uptake was exclusively resided in the polyphenol fraction. Among the polyphenols tested, only tannic acid and quercitin stimulated the uptake of zinc while others did not influence the uptake. In tune with these results, only tannic acid and quercitin competed with zinquin (a zinc selective fluorophore) for zinc in vitro. Although all the polyphenols tested appear to enhance the expression of metallothionein (MT), the induction was higher with tannic acid, quercitin, and RW extract. Furthermore, phytic acid abrogated the tannic acid-induced MT expression. These results suggest that polyphenol-rich beverages, tannic acid, and quercitin bind and stimulate the zinc uptake and MT expression in Caco-2 cells. PMID:20546406

Sreenivasulu, Kilari; Raghu, Pullakhandam; Nair, K Madhavan

2010-05-01

286

Enhancement of oxygen vacancies and solar photocatalytic activity of zinc oxide by incorporation of nonmetal  

NASA Astrophysics Data System (ADS)

B-doped ZnO and N-doped ZnO powders have been synthesized by mechanochemical method and characterized by TG-DTA, XRD, SEM-EDX, XPS, UV-visible and photoluminescence (PL) spectra. X-ray diffraction data suggests the hexagonal wurtzite structure for modified ZnO crystallites and the incorporation of nonmetal expands the lattice constants of ZnO. The room temperature PL spectra suggest more number of oxygen vacancies exist in nonmetal-doped ZnO than that of undoped zinc oxide. XPS analysis shows the substitution of some of the O atoms of ZnO by nonmetal atoms. Solar photocatalytic activity of B-doped ZnO, N-doped ZnO and undoped ZnO was compared by means of oxidative photocatalytic degradation (PCD) of Bisphenol A (BPA). B-doped ZnO showed better solar PCD efficiency as compare to N-doped ZnO and undoped ZnO. The PCD of BPA follows first order reaction kinetics. The detail mechanism of PCD of Bisphenol A was proposed with the identification of intermediates such as hydroquinone, benzene-1,2,4-triol and 4-(2-hydroxypropan-2-yl) phenol.

Patil, Ashokrao B.; Patil, Kashinath R.; Pardeshi, Satish K.

2011-12-01

287

The effects of transformation and ZnT-1 silencing on zinc homeostasis in cultured cells.  

PubMed

We have previously demonstrated that reducing the availability of zinc with the extracellular chelator diethylenetriaminepentaacetic acid (DTPA) promotes efflux of (65)Zn from rat primary hepatocytes and pituitary cells, but increases retention of label in rat hepatoma (H4IIE) and anterior pituitary tumor (GH3) cell lines. To further understand this differential response between primary cells and the corresponding cancer cell lines, we investigated the effects of immortalizing primary cells on their zinc homeostasis. Rat primary hepatocytes were electroporated with the SV40 large T-antigen-coding plasmid pSV3-neo and selected for neomycin resistance. This resulted in cell division of the normally quiescent hepatocytes. When these cells were prelabeled with (65)Zn, DTPA decreased efflux of (65)Zn, similarly to hepatoma cells and differently from primary hepatocytes. This homeostatic change may be required to account for the greater zinc requirements of dividing cells and be mediated by alterations in the activity of zinc transporter ZnT-1, which is responsible for zinc efflux. To further understand the mechanism of DTPA-induced zinc retention, we down-regulated the expression of ZnT-1 in rat hepatoma cells using vector-based short hairpin RNA interference. Expression of ZnT-1 protein was reduced to approximately 50%. Down-regulation of ZnT-1 resulted in greater retention of (65)Zn in control cells. However, DTPA increased rather than decreased efflux of label from knockdown cells, suggesting that functional ZnT-1 is required for the decreased efflux in response to DTPA. We conclude that ZnT-1 expression is crucial for maintaining zinc homeostasis, in particular, for the enhanced retention of zinc in transformed cells when subjected to zinc deprivation. PMID:21775119

Sankavaram, Kavitha; Freake, Hedley C

2011-07-19

288

Development of single cell protectors for sealed silver-zinc cells, phase 1  

Microsoft Academic Search

A single cell protector (SCP) assembly capable of protecting a single silver-zinc (Ag Zn) battery cell was designed, fabricated, and tested. The SCP provides cell-level protection against overcharge and overdischarge by a bypass circuit. The bypass circuit consists of a magnetic-latching relay that is controlled by the high and low-voltage limit comparators. Although designed specifically for secondary Ag-Zn cells, the

M. S. Imamura; R. L. Donovan; J. W. Lear; B. Murray

1976-01-01

289

Upconverter solar cells: materials and applications  

Microsoft Academic Search

Spectral conversion of sunlight is a promising route to reduce spectral mismatch losses that are responsible for the major part of the efficiency losses in solar cells. Both upconversion and downconversion materials are presently explored. In an upconversion process, photons with an energy lower than the band gap of the solar cell are converted to higher energy photons. These higher

J. de Wild; A. Meijerink; J. K. Rath; W. G. J. H. M. van Sark; R. E. I. Schropp

2011-01-01

290

Calibration of Solar Cells in Terrestrial Sunlight.  

National Technical Information Service (NTIS)

A method of calibrating solar cells in sunlight is described. This method has been used for at least 15 years, and produces a value of the solar cell's short circuit current for any predetermined space of terrestrial condition. The main advantage of this ...

M. A. H. Davies C. Goodbody

1991-01-01

291

Solar cell parameter extraction using genetic algorithms  

Microsoft Academic Search

In this paper, a technique based on genetic algorithms is proposed for improving the accuracy of solar cell parameters extracted using conventional techniques. The approach is based on formulating the parameter extraction as a search and optimization problem. Current-voltage data used were generated by simulating a two-diode solar cell model of specified parameters. The genetic algorithm search range that simulates

Joseph A. Jervase; Hadj Bourdoucen; Ali Al-Lawati

2001-01-01

292

Si concentrator solar cell development. [Final report  

SciTech Connect

This is the final report of a program to develop a commercial, high-efficiency, low-cost concentrator solar cell compatible with Spectrolab`s existing manufacturing infrastructure for space solar cells. The period covered is between 1991 and 1993. The program was funded through Sandia National Laboratories through the DOE concentrator initiative and, was also cost shared by Spectrolab. As a result of this program, Spectrolab implemented solar cells achieving an efficiency of over 19% at 200 to 300X concentration. The cells are compatible with DOE guidelines for a cell price necessary to achieve a cost of electricity of 12 cents a kilowatthour.

Krut, D.D. [Spectrolab, Inc., Sylmar, CA (United States)

1994-10-01

293

US Polycrystalline Thin Film Solar Cells Program.  

National Technical Information Service (NTIS)

The Polycrystalline Thin Film Solar Cells Program, part of the United States National Photovoltaic Program, performs R and D on copper indium diselenide and cadmium telluride thin films. The objective of the Program is to support research to develop cells...

H. S. Ullal K. Zweibel R. L. Mitchell

1989-01-01

294

Multiple quantum well top cells for multijunction concentrator solar cells  

Microsoft Academic Search

High efficiency quantum well GaAs solar cells have been successfully applied in commercial multijunction concentrator cells to increase the absorption in the infrared and provide variability of the absorption edge to optimise energy harvesting. Multiple quantum well (MQW) top cells can further improve the performance of multijunction solar cells since the absorption edge of top and middle subcells can be

Kan-Hua Lee; Keith W. J. Barnham; Benjamin C. Browne; James P. Connolly; Jessica G. J. Adams; Rob J. Airey; Nicholas J. Ekins-Daukes; Markus Fuhrer; Victoria Rees; Mathew Lumb; Alison L. Dobbin; Massimo Mazzer; John S. Roberts; Thomas N. D. Tibbits

2011-01-01

295

Shelf and cycle life evaluation of silver--zinc cells. [Various separators  

Microsoft Academic Search

Sterilized and control silver--zinc cells with various separator systems were given extended shelf and cycle life tests. Only cells with a separator system of methacrylic acid graft on cross-linked polyethylene were not sterilized. The data showed that the open-circuit voltage cannot be used to predict the capacity of a silver--zinc cell; but, if the open-circuit voltage of a cell drops

R. S. Bogner; A. A. Uchiyama

1969-01-01

296

Monolithic Cascade-Type Solar Cells.  

National Technical Information Service (NTIS)

Solar cells consist of a semiconductor base, a bottom cell with a band-gap energy of E1, and a top cell with a band-gap energy of E2, and 0.96 E1 1.36 eV and (0.80 E + 0.77) eV E2 (0.80 E1 + 0.92) eV. A monolithic cascade-type solar cell was prepared with...

S. Yamamoto A. Shibukawa M. Yamaguchi

1985-01-01

297

Induction of Apoptosis of Bladder Cancer Cells by Zinc-Citrate Compound  

PubMed Central

Purpose Zinc is one of the trace minerals in the body and is known to have an anticancer effect by inducing apoptosis in prostate cancer. We aimed to investigate the antiproliferative effects of a zinc-citrate compound in bladder cancer. Materials and Methods A bladder cancer cell line (MBT-2) was treated with a zinc-citrate compound at different time intervals and concentrations. Mitochondrial (m)-aconitase activity was determined by use of the aconitase assay. DNA laddering analysis was performed to investigate apoptosis of MBT-2 cells. The molecular mechanism of apoptosis was investigated by Western blot analysis of p53, p21waf1, Bcl-2, Bcl-xL, and Bax and also by caspase-3 activity analysis. Results Treatment with the zinc-citrate compound resulted in a time- and dose-dependent decrease in cell number of MBT-2 cells. M-aconitase activity was significantly decreased. DNA laddering analysis indicated apoptosis of MBT-2 cells. The zinc-citrate compound increased the expression of p21waf1 and p53 and reduced the expression of Bcl-2 and Bcl-xL proteins but induced expression of Bax protein. The zinc-citrate compound induced apoptosis of MBT-2 cells by activation of the caspase-3 pathway. Conclusions We have shown that a zinc-citrate compound induces apoptotic cell death in a bladder cancer cell line, MBT-2, by caspase-3 activation through up-regulation of apoptotic proteins and down-regulation of antiapoptotic proteins.

Hong, Sung-Hoo; Choi, Yong Sun; Cho, Hyuk Jin; Lee, Ji Youl; Hwang, Tae-Kon

2012-01-01

298

Early Hematopoietic Zinc Finger Protein Prevents Tumor Cell Recognition by Natural Killer Cells1  

PubMed Central

Early hematopoietic zinc finger/zinc finger protein 521 (EHZF/ZNF521) is a novel zinc finger protein expressed in hematopoietic stem and progenitor cells and is down-regulated during their differentiation. Its transcript is also abundant in some hematopoietic malignancies. Analysis of the changes in the antigenic profile of cells transfected with EHZF cDNA revealed up-regulation of HLA class I cell surface expression. This phenotypic change was associated with an increased level of HLA class I H chain, in absence of detectable changes in the expression of other Ag-processing machinery components. Enhanced resistance of target cells to NK cell-mediated cytotoxicity was induced by enforced expression of EHZF in the cervical carcinoma cell line HeLa and in the B lymphoblastoid cell line IM9. Preincubation of transfected cells with HLA class I Ag-specific mAb restored target cell susceptibility to NK cell-mediated lysis, indicating a specific role for HLA class I Ag up-regulation in the NK resistance induced by EHZF. A potential clinical significance of these findings is further suggested by the inverse correlation between EHZF and MHC class I expression levels, and autologous NK susceptibility of freshly explanted multiple myeloma cells.

La Rocca, Rosanna; Fulciniti, Mariateresa; Lakshmikanth, Tadepally; Mesuraca, Maria; Ali, Talib Hassan; Mazzei, Valerio; Amodio, Nicola; Catalano, Lucio; Rotoli, Bruno; Ouerfelli, Ouathek; Grieco, Michele; Gulletta, Elio; Bond, Heather M.; Morrone, Giovanni; Ferrone, Soldano; Carbone, Ennio

2009-01-01

299

Phosphates, phosphites, and phosphides in environmental samples.  

PubMed

The common assumption that phosphorus occurs exclusively as phosphate in the environment is deserving of increased scrutiny. If a sample contained reduced phosphorus compounds (P in an oxidation state of less than +5), standard methods of phosphorus determination would incorrectly classify the compounds mostly as organic P, although significant fractions were sometimes misclassified as orthophosphates and condensed P. The disappearance of gaseous hydrogen phosphide (PH3) from samples was a function of solution composition, in that certain acids and metals enhanced removal whereas other constituents increased PH3 stability. No previously used extraction method could detect a significant portion of reduced phosphorus in representative samples by measuring PH3 evolution, particularly for highly recalcitrant iron phosphides. Despite analytical limitations, clear evidence was gathered that reduced phosphorus compounds can be leached from cast iron to water and that reduced phosphorus is also present in the scale (rust) that forms on the metal. PMID:12680671

Morton, Siyuan C; Glindemann, Dietmar; Edwards, Marc A

2003-03-15

300

Effects of electronic correlations on the mechanical properties of Gallium Phosphide using density functional theory (DFT+U)  

NASA Astrophysics Data System (ADS)

Developing an efficient material for solar energy conversion and storage has been an important task for many scientists working on renewable energy technology. Gallium phosphide (GaP) alloys are among the materials that have potential to be used in the solar technology. Hence, we investigate the elastic property, mainly the bulk modulus, and electronic properties of GaP. The goal of this work is to study the effect of electron correlation on the mechanical stability of GaP. The calculation of energy as a function of cell volume has been performed using density functional theory with U-parameter (DFT+U) The Birch-Murnaghan equation of state is used to calculate equilibrium cell volume, total energy, bulk modulus, B0, and its first pressure derivative, B0^'. The bulk modulus obtained using different U-parameter was compared with published experimental values. The use of U-parameter in Gallium d-orbital has increased the theoretical value of bulk modulus, making it closer to the experimental value. On the other hand, increasing values of U on Phosphorus p-orbital decreases the bulk modulus further. The physical consequences of these results will be discussed.

Khatri, Prashant; Butler, Brandon; Turner, John A.; Huda, Muhammad N.

2011-10-01

301

Strongly Photonic Macroporous Gallium Phosphide Networks  

Microsoft Academic Search

A photo-assisted electrochemical etching technique to fabricate macropores in single-crystalline gallium phosphide (GaP) with variable porosity has been developed. Scanning electron microscopy and x-ray diffraction experiments confirm that the material consists of three-dimensional, interconnected ran- dom networks with pore sizes of about 150 nanometers. Optical transmission measurements demonstrate that the nonabsorbing disordered structures strongly scatter light. The photonic strength is

Frank J. P. Schuurmans; Jao van de Lagemaat

1999-01-01

302

Aluminium phosphide poisoning: a case report.  

PubMed

This paper reports the case of a family in which three children were presented at Emergency Room (ER) with poisoning after the use of a pesticide at home. Initially, the cases were managed as routine cases of organophosphorus poisoning; however, the death of two children made the health team members realise that the poison's effects were delayed and devastating. Later, the compound was identified as Aluminium Phosphide (ALP), and the life of the last surviving child in the family was saved. PMID:22455303

Hirani, Shela Akbar Ali; Rahman, Arshalooz

303

Evaluation of critical materials in five additional advance design photovoltaic cells  

NASA Astrophysics Data System (ADS)

Potential material supply constraints due to the large scale deployment of five advanced photovoltaic (PV) cell designs were identified and strategies to reduce the impacts of these production capacity limitations and potential future material are suggested. The Critical Materials Assessment Program (CMAP) screens the designs and their supply chains and identifies potential shortages which might preclude large scale use of the technologies. The results of the screening of five advanced v cell designs are presented: (1) indium phosphide/cadmium sulfide; (2) zinc phosphide; (3) cadmium telluride/cadmium sulfide; (4) copper indium selenium; and (5) cadmium selenide photoelectrochemical. Each of these five cells is screened individually. The CMAP methodology, used to identify critical materials, is described. Detailed characterizations of the advanced photovoltaic cell designs, descriptions of additional cell production processes, and the results are presented.

Smith, S. A.; Watts, R. L.; Martin, P.; Gurwell, W. E.

1981-02-01

304

Gassing characteristics of high capacity, high energy density rechargeable silver zinc cells  

Microsoft Academic Search

Silver zinc batteries have been used safely for many years in a myriad of applications. With the advent of high energy density, semi-closed propulsion systems, the gassing characteristics of silver zinc cells have come under closer scrutiny from both a quantity standpoint as well as quality. A body of work was undertaken to characterize the gassing of a high energy

Z. Adamedes

1998-01-01

305

Divalent silver oxide-zinc cell having a unipotential discharge level  

Microsoft Academic Search

An alkaline silver oxide--zinc cell is described which has a negative electrode, an alkaline electrolyte, a positive electrode comprising divalent silver oxide housed in a positive terminal container, and a separator disposed between the negative electrode and the positive electrode. A discontinuous oxidizable metal, such as a zinc screen, is interposed between the positive electrode and the inner wall of

Kozawa

1975-01-01

306

Postnatal development of zinc-containing cells and neuropil in the visual cortex of the mouse  

Microsoft Academic Search

The postnatal development of zinc-containing synaptic boutons and their cells of origin in the visual cortex of a pigmented mouse is described. Two phases can be distinguished. During the early phase zinc-containing neuropil is first apparent by postnatal day 3. By day 7 a light, but distinct neuropil staining sketches the primary and secondary visual cortices. The primary visual area

B. Garrett; L. Slomianka

1992-01-01

307

Zinc transporter 7 is located in the cis-Golgi apparatus of mouse choroid epithelial cells  

Technology Transfer Automated Retrieval System (TEKTRAN)

The cellular localization of zinc transporter 7 protein in the mouse choroid plexus, an area on the ventricles of the brain where cerebrospinal fluid (CSF) is produced, was examined in this study. Zinc transporter 7 expressing cells were detected in the third, lateral, and fourth ventricles of the m...

308

Subendocardial infarction in a young survivor of aluminium phosphide poisoning  

Microsoft Academic Search

Aluminium phosphide is a solid fumigant pesticide and has systemic toxicity due to liberation of phosphine gas. We report a case of aluminium phosphide poisoning with systemic toxicity in a 16-year-old patient who developed previously undocumented complication of subendocardial infarction, with characteristic electrocardiographic changes reverting back to normal after a period of 10 weeks, even though the patient had clinical

Rajeev M Kaushik; Reshma Kaushik; Sukhdev K Mahajan

2007-01-01

309

Integration of Solar Cells on Top of CMOS Chips Part I: aSi Solar Cells  

Microsoft Academic Search

We present the monolithic integration of deep- submicrometer complementary metal-oxide-semiconductor (CMOS) microchips with a-Si:H solar cells. Solar cells are manufactured directly on the CMOS chips. The microchips maintain comparable electronic performance, and the solar cells show efficiency values above 7%. The yield of photovoltaic cells on planarized CMOS chips is 92%. This integration allows integrated energy harvesting using established process

Jiwu Lu; Alexey Y. Kovalgin; Karine H. M. van der Werf; Ruud E. I. Schropp; Jurriaan Schmitz

2011-01-01

310

Efficient direct ZnO/CIS solar cells  

NASA Astrophysics Data System (ADS)

This paper describes investigations of CIS solar cells with ZnO window layers deposited by MOCVD. These studies have been conducted with graded absorber CIS substrates obtained from Siemens Solar. Cell fabrication involves surface preparation of the Siemens substrate, growth of 200 to 400 A? of undoped ZnO by MOCVD, deposition of a highly conducting ZnO top contact layer and deposition of a Ni/Ag collector grid. MOCVD growth of ZnO is accomplished in a SPIRE 500XT reactor by reacting a zinc adduct and tetrahydrofuran. Processing development has been conducted by forming test cells on ZnO/CIS structures by depositing thin, transparent Al contacts 2.8 mm in diameter on top of the ZnO window layer to serve as contacts. Several cells have been completed with a total area efficiency >=11.0%, with the best result being 11.3%. The best active area efficiency is approximately 12%. Other topics discussed include current-voltage characteristics of direct ZnO/CIS cells.

Olsen, Larry C.; William Addis, F.; Lei, Wenhua; Li, Jun

1996-01-01

311

Heat-sterilized silver oxide--zinc cells cycle life studies. [4. 2 Ah  

Microsoft Academic Search

A JPL study was conducted to evaluate the cell design parameters that contribute to the cycle life of sealed, heat-sterilized silver oxide--zinc cells. Test cells having a rated capacity of 4.2 Ah were fabricated from zinc oxide electrodes prepared by the sintered Teflon process. Two separator variations were evaluated, one having acrylic acid and the other, methacrylic acid, grafted to

Arms

1973-01-01

312

Enhancement of oxygen vacancies and solar photocatalytic activity of zinc oxide by incorporation of nonmetal  

SciTech Connect

B-doped ZnO and N-doped ZnO powders have been synthesized by mechanochemical method and characterized by TG-DTA, XRD, SEM-EDX, XPS, UV-visible and photoluminescence (PL) spectra. X-ray diffraction data suggests the hexagonal wurtzite structure for modified ZnO crystallites and the incorporation of nonmetal expands the lattice constants of ZnO. The room temperature PL spectra suggest more number of oxygen vacancies exist in nonmetal-doped ZnO than that of undoped zinc oxide. XPS analysis shows the substitution of some of the O atoms of ZnO by nonmetal atoms. Solar photocatalytic activity of B-doped ZnO, N-doped ZnO and undoped ZnO was compared by means of oxidative photocatalytic degradation (PCD) of Bisphenol A (BPA). B-doped ZnO showed better solar PCD efficiency as compare to N-doped ZnO and undoped ZnO. The PCD of BPA follows first order reaction kinetics. The detail mechanism of PCD of Bisphenol A was proposed with the identification of intermediates such as hydroquinone, benzene-1,2,4-triol and 4-(2-hydroxypropan-2-yl) phenol. - Graphical Abstract: B-doped ZnO and N-doped ZnO synthesized by mechanochemical method were characterized by various techniques. Solar photocatalytic degradation of Bisphenol-A is in the order of B-ZnO>N-ZnO>ZnO. Highlights: Black-Right-Pointing-Pointer B-doped ZnO and N-doped ZnO powders have been synthesized by mechanochemical method. Black-Right-Pointing-Pointer PL spectra suggest oxygen vacancies are in order of B-doped ZnO>N-doped ZnO>ZnO. Black-Right-Pointing-Pointer Solar PCD efficiency is in order of B-doped ZnO>N-doped ZnO>ZnO for Bisphenol A.

Patil, Ashokrao B. [Department of Chemistry, University of Pune, Ganeshkhind, Pune 411007 (India); Patil, Kashinath R. [Center for Materials Characterization, National Chemical Laboratory, Pune 411008 (India); Pardeshi, Satish K., E-mail: skpar@chem.unipune.ac.in [Department of Chemistry, University of Pune, Ganeshkhind, Pune 411007 (India)

2011-12-15

313

ZnSe Window Layers for GaAs and GaInP2 Solar Cells.  

National Technical Information Service (NTIS)

This report concerns studies of the use of ZnSe as a window layer for GaAs solar cells. Well-oriented crystalline ZnSe films on (100) single crystal GaAs substrates were grown by MOCVD. In particular, ZnSe films were grown by reacting a zinc adduct with h...

L. C. Olsen

1995-01-01

314

Effect of improved zinc status on T helper cell activation and TH1\\/TH2 ratio in healthy elderly individuals  

Microsoft Academic Search

Mild zinc deficiency is a common condition in healthy elderly individuals leading to impaired cell-mediated immune response. Here we report the effect of improved zinc status on TH1\\/TH2 balance and on the activation status of T helper cells in 19 healthy elderly subjects aged 69.8 ± 5.1 years. Our investigations revealed a mild zinc deficiency which was adjusted by oral zinc supplementation for

Laura Kahmann; Peter Uciechowski; Sabine Warmuth; Marco Malavolta; Eugenio Mocchegiani; Lothar Rink

2006-01-01

315

Characterising dye-sensitized solar cells  

NASA Astrophysics Data System (ADS)

With growing energy and environmental concerns due to fossil fuel depletion and global warming there is an increasing attention being attracted by alternative and/or renewable sources of power such as biomass, hydropower, geothermal, wind and solar energy. In today's society there is a vast and in many cases not fully appreciated dependence on electrical power for everyday life and therefore devices such as PV cells are of enormous importance. The more widely used and commercially available silicon (semiconductor) based cells currently have the greatest efficiencies, however the manufacturing of these cells is complex and costly due to the cost and difficulty of producing and processing pure silicon. One new direction being explored is the development of dye-sensitised solar cells (DSSC). The SFI Strategic Research Centre for Solar Energy Conversion is a new research cluster based in Ireland, formed with the express intention of bringing together industry and academia to produce renewable energy solutions. Our specific area of research is in biomimetic dye sensitised solar cells and their electrical properties. We are currently working to develop test equipment, and optoelectronic models describing the performance and behaviors of dye-sensitised solar cells (Grätzel Cells). In this paper we describe some of the background to our work and also some of our initial experimental results. Based on these results we intend to characterise the opto-electrical properties and bulk characteristics of simple dye-sensitised solar cells and then to proceed to test new cell compositions.

Tobin, Laura L.; O'Reilly, Thomas; Zerulla, Dominic; Sheridan, John T.

2009-08-01

316

Solar cells based on gallium antimonide  

SciTech Connect

Liquid-phase epitaxy and diffusion from the gas phase have been used to create various kinds of GaSb-based solar cell structures intended for use in cascaded solar-radiation converters. A narrow-gap (GaSb) solar cell was studied in tandem based on a combination of semiconductors GaAs-GaSb (two p-n junctions) and GaInP/GaAs-GaSb (three p-n junctions). The maximum efficiency of photovoltaic conversion in GaSb behind the wide-gap cells is {eta} = 6.5% (at sunlight concentration ratio of 275X, AM1.5D Low AOD spectrum)

Andreev, V. M.; Sorokina, S. V.; Timoshina, N. Kh.; Khvostikov, V. P., E-mail: vikhv@scell.ioffe.ru; Shvarts, M. Z. [Russian Academy of Sciences, Ioffe Physicotechnical Institute (Russian Federation)

2009-05-15

317

Present status of buried contact solar cells  

Microsoft Academic Search

Recent years have seen substantially increased performance for laboratory Silicon solar cells. The standard commercial screen-printing cell process sequence appears unable to take advantage of many of these improvements. Consequently, until recently, the efficiency of commercial cells has lagged considerably. The buried contact cell provides a commercial approach able to bridge this gap. During 1990 and 1991, the first results

M. A. Green; S. R. Wenham; J. Zhao; S. Bowden; A. M. Milne; M. Taouk; F. Zhang

1991-01-01

318

Solar Cell Calibration Experiments on Les-6.  

National Technical Information Service (NTIS)

The sixth Lincoln Laboratory Experimental Satellite (LES-6) was placed in a synchronous orbit on 26 September 1968. Among instrumentation on board is a solar cell calibration experiment to measure the V-I characteristics at various angles of solar inciden...

F. W. Sarles A. G. Stanley C. Burrowes

1968-01-01

319

High transmittance and low resistive ZnO:Al films for thin film solar cells  

Microsoft Academic Search

Transparent conductive oxides (TCO) are indispensable as front electrode for most of the thin film solar cells. Thin films of aluminum-doped zinc oxide (ZnO:Al), one of the promising TCOs, were prepared by radio frequency (rf) magnetron sputtering on glass (Corning 1737) substrates as a function of the deposition condition. Argon gas pressure during deposition was kept in the range 0.04–1.33

Jinsu Yoo; Jeonghul Lee; Seokki Kim; Kyunghoon Yoon; I. Jun Park; S. K. Dhungel; B. Karunagaran; D. Mangalaraj; Junsin Yi

2005-01-01

320

Final Report: Sintered CZTS Nanoparticle Solar Cells on Metal Foil; July 26, 2011 - July 25, 2012  

SciTech Connect

This is the final report covering 12 months of this subcontract for research on high-efficiency copper zinc tin sulfide (CZTS)-based thin-film solar cells on flexible metal foil. Each of the first three quarters of the subcontract has been detailed in quarterly reports. In this final report highlights of the first three quarters will be provided and details will be given of the final quarter of the subcontract.

Leidholm, C.; Hotz, C.; Breeze, A.; Sunderland, C.; Ki, W.; Zehnder, D.

2012-09-01

321

Panchromatic trichromophoric sensitizer for dye-sensitized solar cells using antenna effect.  

PubMed

The first trichromophoric sensitizer, consisting of covalently linked boradiazaindacene (BODIPY), zinc porphyrin (ZnP), and squaraine (SQ) units, has been synthesized by Heck alkynylation to obtain a panchromatic dye, for dye sensitized solar cells (DSSCs). Efficient intramolecular energy transfers (ET) were observed between all chromophoric subunits and enhance the overall conversion efficiency by 25%. The antenna effect is demonstrated by the photoaction spectrum which features all of a chromophore's absorption bands. PMID:21721515

Warnan, Julien; Buchet, Fabien; Pellegrin, Yann; Blart, Errol; Odobel, Fabrice

2011-07-01

322

Surfactant-aided solvothermal synthesis of dinickel phosphide nanocrystallites using red phosphorus as starting materials  

Microsoft Academic Search

A surfactant-aided solvothermal synthesis route has been proposed to produce well-dispersed dinickel phosphide nanocrystallites by using nickel dichloride and nontoxic red phosphorus as starting materials. It was found that the polymeric surfactant polyacrylamide played a crucial role in the reaction dynamic process. X-ray powder diffraction pattern indicated that the products were hexagonal phase with cell constants a=0.5846nm, c=0.3368nm, which was

Jianwei Liu; Xiangyang Chen; Mingwang Shao; Changhua An; Weichao Yu; Yitai Qian

2003-01-01

323

Inkjet printing of carrier transport layers for inverted organic solar cells  

NASA Astrophysics Data System (ADS)

Inverted organic solar cells, which utilize a transparent cathode and a high work function metal anode, have been the subject of extensive research. Their advantages over conventional organic solar cells include increased resistance to environmental degradation and compatibility with large area fabrication techniques. Carrier transport layers are essential for achieving high power conversion efficiencies in inverted organic solar cells and therefore need to be compatible with these large area fabrication techniques. Inkjet printing is one such technique that can be integrated into the low cost mass production of these cells via roll to roll fabrication. N-type metal oxides such as ZnO or zinc tin oxide (ZTO) have been previously used as electron transport layers for inverted cells, but only as spin coated films. We have developed inkjet printable ZTO solutions for use as electron transport layers in inverted organic solar cells, and achieve power conversion efficiencies of over 3% in inverted P3HT:PC71BM solar cells. We also discuss the effect of printing parameters on the electrical performance of these layers in inverted organic solar cells.

Danielson, Eric; Subbaraman, Harish; Dodabalapur, Ananth

2013-09-01

324

Upregulation of haeme oxygenase-1 by zinc in HCT-116 cells.  

PubMed

Haeme oxygenase-1 (HO-1) is often viewed as a cytoprotective gene. Toxic heavy metals induce HO-1, but it is unclear whether particular metal micronutrients also induce HO-1. Hence, the ability of exogenously-added copper, iron and zinc to influence HO-1 expression in HCT-116 cells was evaluated. Under the chosen experimental conditions, only zinc noticeably increased the expression of HO-1 mRNA and protein. Concurrently, zinc decreased non-protein thiol levels to a certain extent, but zinc did not increase the production of reactive oxygen species (ROS). Moreover, ascorbate and Trolox did not inhibit zinc-induced HO-1 upregulation. In contrast, deferoxamine blunted the induction of HO-1 mRNA, protein, and enzymatic activity caused by zinc. Additionally, N-acetylcysteine and Tiron inhibited zinc-induced HO-1 upregulation and also nuclear translocation of nuclear factor erythroid 2-related factor 2 (Nrf2). Collectively, these findings suggest that zinc at above normal levels upregulates HO-1 expression in HCT-116 cells in a ROS-independent manner. PMID:22564156

Smith, Abigail F; Loo, George

2012-06-08

325

Zinc induces cell cycle arrest and apoptosis by upregulation of WIG-1 in esophageal squamous cancer cell line EC109.  

PubMed

Zinc deficiency was implicated in the etiologies of human esophageal squamous cell carcinoma (ESCC). Wild-type p53-induced gene 1 (WIG-1), a kind of zinc finger protein, was cloned from the human 3q26.3 region and encoded a putative polypeptide of 289 amino acids. Our previous studies have demonstrated that the expression of WIG-1 was downregulated in ESCC tissues. Herein, we investigated the effect of zinc on cell proliferation, apoptosis, as well as expression of WIG-1 in EC109 cells. Meanwhile, an RNAi vector of WIG-1 was transfected into EC109 cells and the effect of zinc on WIG-1 expression was investigated. We found that zinc could suppress cell proliferation and induce G0/G1 cell cycle arrest and apoptosis of EC109, and this efficacy might result from the expression altering of several apoptosis-related genes, such as Bax, p21 ( WAF ), and cyclin D1. In particular, upregulation of WIG-1 was observed after zinc supplementation, indicating that WIG-1 might be involved in the zinc-induced cell cycle arrest and apoptosis of EC109 cells by regulating the expression of Bax, p21 ( WAF ), and cyclin D1. PMID:21559779

Guo, Wei; Zou, Ying-Bo; Jiang, Yao-Guang; Wang, Ru-Wen; Zhao, Yun-Ping; Ma, Zheng

2011-05-11

326

Nanocomposites for organic and hybrid organic-inorganic solar cells  

Microsoft Academic Search

The importance of nanocomposites materials such as carbon nanotubes-polymers composites for the efficient realization of innovative solar cells based on organic as well hybrid organic-inorganic solar cells is more and more evident. We present a study on the realization of dye sensitized solar cells (DSSC) and sublimation deposited solar cells, considering the impact of using nanocomposite materials in the different

A. Reale; T. M. Brown; A. Di Carlo; F. Giannini; F. Brunetti; E. Leonardi; M. Lucci; M. L. Terranova; S. Orlanducci; E. Tamburri; F. Toschi; V. Sessa

2006-01-01

327

Zinc Regulation of Neural Stem Cell Proliferation and Antidepressant Efficacy  

Microsoft Academic Search

Changes in zinc homeostasis are strongly associated with abnormal brain function and a variety of neurological and neuropsychiatric disorders, including depression. It is hypothesized that the neurogenic potential of chronic antidepressant administration contributes to its therapeutic effects in depression. Thus, the goal of this work was to determine the extent to which zinc is needed for antidepressant drug induction of

Tatyana Mullin

2008-01-01

328

Opposite effects of electroporation of red blood cell membranes under the influence of zinc ions.  

PubMed

The goal of the study was to investigate the effects of zinc ions of various concentrations on the nanostructure of membrane of red blood cells in in vitro experiment. The suspension of red blood cells extracted from whole human blood was used. The calibrated electroporation and the atomic force microscopy (AFM) were used to analyse damage to membrane nanostructure. We studied the haemolysis after the electroporation at different zinc concentrations. A low concentration of zinc (0.15-0.5 mM) increased significantly the rate of haemolysis and reduced the residual level of non-haemolyzed cells. At high concentrations of zinc ions (0.5-10 mM), the rate constant was sharply reduced, at the same time the residual level increased. The relationship between haemoglobin coagulants and the zinc concentration was examined. High concentration of zinc caused haemoglobin aggregation. It was shown by AFM that the membrane nanostructure was essentially changed. It was experimentally established that there existed a special point of zinc concentration C = 0.5±0.1 mM at which the course of the conjugate processes on the membranes of red blood cells was changed. PMID:22741531

Kozlova, Elena; Chernysh, Alexander; Moroz, Victor; Sergunova, Victoria; Gudkova, Olga; Fedorova, Mayya; Kuzovlev, Artem

2012-01-01

329

Simple Ion Implantation System for Solar Cells.  

National Technical Information Service (NTIS)

A project has been initiated to investigate simple but effective ion implantation and pulsed annealing techniques for the fabrication of high efficiency silicon solar cells. In particular, the method aims to eliminate the mass analyser and associated comp...

M. J. Kenny J. R. Bird H. G. Broe

1982-01-01

330

Advanced Silicon Space Solar Cells Using Nanotechnology  

SciTech Connect

Application of nanotechnology and advanced optical structures offer new possibilities for improved radiation tolerance in silicon solar cells. We describe the application of subwavelength diffractive structures to enhance optical absorption near the surface, and thereby improve the radiation tolerance.

Gee, J.M.; Ruby, D.S.; Zaidi, S.H.

1999-03-31

331

Screen Printed Interdigitated Back Contact Solar Cell.  

National Technical Information Service (NTIS)

Interdigitated back contact solar cells were made by screen printing dopant materials onto the back surface of a semiconductor substrate in a pair of interdigitated patterns. These dopant materials were then diffused into the substrate to form junctions h...

C. R. Baraona G. A. Mazaris A. T. Chai

1983-01-01

332

Solar Cell Efficiency Tables (Version 34)  

SciTech Connect

Consolidated tables showing an extensive listing of the highest independently confirmed efficiencies for solar cells and modules are presented. Guidelines for inclusion of results into these tables are outlined and new entries since January, 2009 are reviewed.

Green, M. A.; Emery, K.; Hishikawa, Y.; Warta, W.

2009-01-01

333

Solar-cell testing and evaluation  

SciTech Connect

A two year study of the degradation effects in AlGaAs/GaAs solar cells is described. Illuminated current-voltage measurements were made during temperature and humidity cycling and time dependent degradation measurements were recorded.

Stefanakos, E.K.; Collis, W.J.

1982-04-01

334

Effect of zinc deficiency on betacyanin production in a cell suspension culture of table beet (Beta vulgaris L.).  

PubMed

The effect of microelements in the Linsmaier-Skoog (LS) medium on betacyanin production was investigated in suspension cultures of table beet (Beta vulgaris L.). Removing zinc from the medium resulted in a high betacyanin content of the cells, the betacyanin content of the cells decreasing with increasing zinc concentration in the medium. The betacyanin content of cells cultured in the medium without zinc was twice as high as that in the medium containing 0.03 mM of zinc. In the revised LS medium without zinc, the maximum betacyanin yield was obtained of 590 mg/l from a 21-day culture. PMID:11388482

Akita, T; Hina, Y; Nishi, T

2001-04-01

335

Cascade solar cell having conductive interconnects  

DOEpatents

Direct ohmic contact between the cells in an epitaxially grown cascade solar cell is obtained by means of conductive interconnects formed through grooves etched intermittently in the upper cell. The base of the upper cell is directly connected by the conductive interconnects to the emitter of the bottom cell. The conductive interconnects preferably terminate on a ledge formed in the base of the upper cell.

Borden, Peter G. (Menlo Park, CA); Saxena, Ram R. (Saratoga, CA)

1982-10-26

336

Zinc-specific autometallographic in vivo selenium methods: tracing of zinc-enriched (ZEN) terminals, ZEN pathways, and pools of zinc ions in a multitude of other ZEN cells.  

PubMed

In vivo-applied sodium selenide or sodium selenite causes the appearance of zinc-selenium nanocrystals in places where free or loosely bound zinc ions are present. These nanocrystals can in turn be silver enhanced by autometallographic (AMG) development. The selenium method was introduced in 1982 as a tool for zinc-ion tracing, e.g., in vesicular compartments such as synaptic vesicles of zinc-enriched (ZEN) terminals in the central nervous system, and for visualization of zinc ions in ZEN secretory vesicles of, e.g., somatotrophic cells in the pituitary, zymogene granules in pancreatic acinar cells, beta-cells of the islets of Langerhans, Paneth cells of the crypts of Lieberkühn, secretory cells of the tubuloacinar glands of prostate, epithelium of parts of ductus epididymidis, and osteoblasts. If sodium selenide/selenite is injected into brain, spinal cord, spinal nerves containing sympathetic axons, or intraperitoneally, retrograde axonal transport of zinc-selenium nanocrystals takes place in ZEN neurons, resulting in accumulation of zinc-selenium nanocrystals in lysosomes of the neuronal somata. The technique is, therefore, also a highly specific tool for tracing ZEN pathways. The present review includes an update of the 1982 paper and presents evidence that only zinc ions are traced with the AMG selenium techniques if the protocols are followed to the letter. PMID:15684327

Danscher, Gorm; Stoltenberg, Meredin

2005-02-01

337

Evaluation of carbon cryogels used as cathodes for non-flowing zinc–bromine storage cells  

Microsoft Academic Search

Monolithic megaloporous carbon cryogels were examined for their potential applications as cathodic electrodes in secondary zinc–bromine cells. This work investigates the possibility of using their particular macroporous texture as microscopic bromine tanks in a zinc\\/bromine battery. The electrochemical behaviour of a cell based upon such a Br2 electrode was studied and discussed in terms of energy yields, energy storage capability

David Aymé-Perrot; Serge Walter; Zelimir Gabelica; Sabine Valange

2008-01-01

338

Status of polycrystalline solar cell technologies  

Microsoft Academic Search

Thin-film cadmium telluride (CdTe) and thin-film copper indium diselenide (CIS) solar cells are discussed. The issues these technologies face before commercialization are addressed. The authors conclude that high-efficiency (15-18%) polycrystalline silicon modules will dominate the market in the near future, and impressive results for thin-film CdTe and CIS solar cells and their outdoor stability will attract increased interest in these

Vijay K. Kapur; Bulent M. Basol

1991-01-01

339

Towards upconversion for amorphous silicon solar cells  

Microsoft Academic Search

Upconversion of subbandgap light of thin film single junction amorphous silicon solar cells may enhance their performance in the near infrared (NIR). In this paper we report on the application of the NIR–vis upconverter ?-NaYF4:Yb3+(18%) Er3+(2%) at the back of an amorphous silicon solar cell in combination with a white back reflector and its response to infrared irradiation. Current–voltage measurements

J. de Wild; A. Meijerink; J. K. Rath; W. G. J. H. M. van Sark; R. E. I. Schropp

2010-01-01

340

Efficient semitransparent small-molecule organic solar cells  

NASA Astrophysics Data System (ADS)

We present semitransparent small-molecule organic solar cells (OSC) deposited by thermal evaporation onto indium tin oxide (ITO)-coated glass substrates. The devices employ ITO-free ultrathin metal layers as top electrodes, containing 1 nm metal surfactant interlayer for improved morphology. Using a bulk heterojunction of zinc phthalocyanine and C60, sandwiched in between doped dedicated transport layers for efficient charge carrier extraction, power conversion efficiencies comparable to conventional OSC with an intransparent thick back electrode and similar device layout are achieved: the semitransparent OSC yield power conversion efficiencies well above 2% with external quantum efficiencies above 30%-40%. Organic light incoupling layers improve the transmission to up to 50% in the visible part of the optical spectrum.

Meiss, Jan; Leo, Karl; Riede, Moritz K.; Uhrich, Christian; Gnehr, Wolf-Michael; Sonntag, Stefan; Pfeiffer, Martin

2009-11-01

341

Simplified solar cell material tester  

SciTech Connect

A method is described for testing quality of photovoltaic semiconductor material having a thickness of less than one minority carrier diffusion length, for use as solar cells, by determining the minority carrier diffusion length, comprising the steps of: preparing a thin slice of semiconductor material by polishing one side thereof, and preparing the other side thereof with a predetermined surface finish; coupling to both sides of the thin slice of semiconductor material with electrodes; directing lighting having a first predetermined wavelength onto the polished surface of the sice; measuring a first photovoltage developed at the electrodes while light at the first wavelength is applied to the slice; directing light having a second different predetermined wavelength onto the slice; adjusting the light intensity so that the photovoltage developed at the electrodes while light at the second wavelength is applied to the slice is substantially the same as the first photovoltage at the first wavelength; measuring a second intensity of illumination applied to the slice at the second wavelength; determining the ratio of the light intensity at one of the first and second wavelengths relative to the light intensity at the other of the first and second wavelengths; and ascertaining the minority carrier diffusion length from the ratio.

Garlick, G.F.J.

1987-04-07

342

Investigating dye-sensitised solar cells  

NASA Astrophysics Data System (ADS)

At present there is considerable global concern in relation to environmental issues and future energy supplies, for instance climate change (global warming) and the rapid depletion of fossil fuel resources. This trepidation has initiated a more critical investigation into alternative and renewable sources of power such as geothermal, biomass, hydropower, wind and solar energy. The immense dependence on electrical power in today's society has prompted the manufacturing of devices such as photovoltaic (PV) cells to help alleviate and replace current electrical demands of the power grid. The most popular and commercially available PV cells are silicon solar cells which have to date the greatest efficiencies for PV cells. The drawback however is that the manufacturing of these cells is complex and costly due to the expense and difficulty of producing and processing pure silicon. One relatively inexpensive alternative to silicon PV cells that we are currently studying are dye-sensitised solar cells (DSSC or Grätzel Cells). DSSC are biomimetic solar cells which are based on the process of photosynthesis. The SFI Strategic Research Centre for Solar Energy Conversion is a research cluster based in Ireland formed with the express intention of bringing together industry and academia to produce renewable energy solutions. Our specific research area is in DSSC and their electrical properties. We are currently developing testing equipment for arrays of DSSC and developing optoelectronic models which todescribe the performance and behaviour of DSSCs.

Tobin, Laura L.; O'Reilly, Thomas; Zerulla, Dominic; Sheridan, John T.

2010-04-01

343

New reactions involving the oxidative O-, N-, and C-phosphorylation of organic compounds by phosphorus and phosphides in the presence of metal complexes  

Microsoft Academic Search

The mechanisms of new catalytic reactions leading to the formation of di-, and tri-alkyl phosphates, di- and tri-alkyl phosphites, phosphoramidites, phosphazenes, phosphines, and phosphine oxides from hydrogen, copper, and zinc phosphides and white and red phosphorus are analysed. The mechanisms of the activation of the reactants by metal complexes and of the reactions involving the oxidative P-O, P-N, and P-C

Ya A. Dorfman; M. M. Aleshkova; G. S. Polimbetova; L. V. Levina; T. V. Petrova; R. R. Abdreimova; D. M. Doroshkevich

1993-01-01

344

Histiocytic and dendritic reticulum cells shown by a zinc iodide-osmium technique.  

PubMed Central

Structures corresponding to histiocytic and dendritic reticulum cells have been shown in human tonsillar tissue, "reactive" lymph nodes and spleens by means of a zinc iodide-osmium technique. These cell types have been shown in various locations in these tissues using paraffin and resin embedded sections produced after fixation/staining of the tissue in zinc iodide-osmium. The quality of morphology attained by this procedure is much improved compared with the demonstration of the two cell types by means of alpha-naphthyl acetate esterase reactions performed on frozen sections. The zonal architecture of the lymphoid follicle is emphasised by this technique. In lymph nodes, sinus lining cells are also shown. Lymphoid cells, polymorphs, fibroblasts, and endothelial cells are negative with the zinc iodide-osmium method. In addition, interdigitating cells are not stained. The results of this procedure are compared with those with those of other methods for the demonstration of histiocytic and dendritic reticulum cells. Images

Crocker, J; Hopkins, M

1984-01-01

345

Incorporating multiple energy relay dyes in liquid dye-sensitized solar cells.  

PubMed

Panchromatic response is essential to increase the light-harvesting efficiency in solar conversion systems. Herein we show increased light harvesting from using multiple energy relay dyes inside dye-sensitized solar cells. Additional photoresponse from 400-590 nm matching the optical window of the zinc phthalocyanine sensitizer was observed due to Förster resonance energy transfer (FRET) from the two energy relay dyes to the sensitizing dye. The complementary absorption spectra of the energy relay dyes and high excitation transfer efficiencies result in a 35% increase in photovoltaic performance. PMID:21344598

Yum, Jun-Ho; Hardin, Brian E; Hoke, Eric T; Baranoff, Etienne; Zakeeruddin, Shaik M; Nazeeruddin, Mohammad K; Torres, Tomas; McGehee, Michael D; Grätzel, Michael

2011-01-05

346

Incorporating Multiple Energy Relay Dyes in Liquid Dye-Sensitized Solar Cells.  

PubMed

Panchromatic response is essential to increase the light-harvesting efficiency in solar conversion systems. Herein we show increased light harvesting from using multiple energy relay dyes inside dye-sensitized solar cells. Additional photoresponse from 400-590?nm matching the optical window of the zinc phthalocyanine sensitizer was observed due to Förster resonance energy transfer (FRET) from the two energy relay dyes to the sensitizing dye. The complementary absorption spectra of the energy relay dyes and high excitation transfer efficiencies result in a 35?% increase in photovoltaic performance. PMID:21210404

Yum, Jun-Ho; Hardin, Brian E; Hoke, Eric T; Baranoff, Etienne; Zakeeruddin, Shaik M; Nazeeruddin, Mohammad K; Torres, Tomas; McGehee, Michael D; Grätzel, Michael

2011-01-01

347

Pyrrolidine dithiocarbamate-zinc(II) and -copper(II) complexes induce apoptosis in tumor cells by inhibiting the proteasomal activity  

Microsoft Academic Search

Zinc and copper are trace elements essential for proper folding, stabilization and catalytic activity of many metalloenzymes in living organisms. However, disturbed zinc and copper homeostasis is reported in many types of cancer. We have previously demonstrated that copper complexes induced proteasome inhibition and apoptosis in cultured human cancer cells. In the current study we hypothesized that zinc complexes could

Vesna Milacic; Di Chen; Lorena Giovagnini; Alejandro Diez; Dolores Fregona; Q. Ping Dou

2008-01-01

348

Solar energy-conversion processes in organic solar cells  

NASA Astrophysics Data System (ADS)

Organic semiconducting materials have demonstrated attractive light-absorption and photocurrent-generation functions due to their delocalized ? electrons as well as intra-molecular and inter-molecular charge separation processes. On the other hand, organic semiconducting materials have easy property tuning, are mechanically flexible, and have large-area thin film formation properties. As a result, organic materials have become potential candidates in solar energy applications. This article will review critical energy-conversion processes in organic solar cells with the focus on singlet and triplet photovoltaic responses.

Xu, Zhihua; Zang, Huidong; Hu, Bin

2008-09-01

349

Monolithic solar cell panel of amorphous silicon  

Microsoft Academic Search

A monolithic solar cell panel has been fabricated using hydrogenated amorphous silicon (a-Si:H) as the semiconductor material. This device consists of a plate glass substrate bearing a number of long, narrow, parallel cells electrically connected in series along the lengths of the cells. It features several characteristics which make it uniquely attractive for large area devices (up to several sq

J. J. Hanak

1979-01-01

350

Development and fabrication of large vented nickel--zinc cells. Final report. [300 Ah  

Microsoft Academic Search

A preliminary cell design for a 300-Ah vented nickel--zinc cell was established based on volume requirements and cell component materials selected by NASA Lewis Research Center. A 100-Ah cell configuration was derived from the 300-Ah cell design utilizing the same size electrodes, separators, and cell terminal hardware. The first cells fabricated were four groups of three cells each in the

Donnel; C. P. I

1975-01-01

351

Effects of the Ca ionophore A23187 on zinc-induced apoptosis in C6 glioma cells  

Microsoft Academic Search

Zinc ions are essential, but at elevated concentrations, they also have toxic effects on mammalian cells. Zinc plays a crucial\\u000a role in cell proliferation and differentiation and it even protects cells against apoptosis caused by various reagents. On\\u000a the other hand, zinc at high concentrations causes cell death that was characterized as apoptotic by internucleosomal DNA\\u000a fragmentation, formation of apoptotic

Sven Jansen; Jürgen Arning; Detmar Beyersmann

2003-01-01

352

Human fetal endothelial cells acquire Zinc(II) from both the protein bound and nonprotein bound pools in serum  

Microsoft Academic Search

To help determine physiologically important routes by which zinc (Zn) is acquired by human fetal vascular endothelium, the\\u000a authors incubated cultured umbilical vein endothelial cells with65Zn(II)-tracer labeled human fetal whole serum, ultrafiltrate (containing low molecular mass serum zinc complexes), and dialyzed\\u000a serum (containing protein-bound zinc). Zinc from whole serum and from both serum fractions entered a rapidly labeled cellular\\u000a compartment

Christopher M. R. Bax; David L. Bloxam

1997-01-01

353

Hydrothermal synthesis method of nickel phosphide nanoparticles  

NASA Astrophysics Data System (ADS)

Nanometer nickel phosphide compounds (Ni2P and Ni12P5) were synthesized via a mild hydrothermal method with red phosphor and nickel chloride as raw materials. XRD, EDS, TEM and SEM analysis were employed to characterize the obtained products. The results showed that the as-prepared products were well crystallized and particle sizes ranged from 10 to 40 nm. Effects of raw material ratios and initial pH of reaction system on the final products were investigated. The result showed that increased P/Ni ratio benefited the formation of Ni2P but went against obtaining Ni12P5 and nanoparticles were obtained only in alkaline environment.

Wang, Bo; Huang, Xiang; Zhu, Zhibin; Huang, He; Dai, Jinhui

2012-12-01

354

P/N InP solar cells on Ge wafers  

NASA Astrophysics Data System (ADS)

Indium phosphide (InP) P-on-N one-sun solar cells were epitaxially grown using a metalorganic chemical vapor deposition process on germanium (Ge) wafers. The motivation for this work is to replace expensive InP wafers, which are fragile and must be thick and therefore heavy, with less expensive Ge wafers, which are stronger, allowing use of thinner, lighter weight wafers. An intermediate InxGs1-xP grading layer starting as In(0.49)Ga(0.51) at the GaAs-coated Ge wafer surface and ending as InP at the top of the grading layer (backside of the InP cell) was used to attempt to bend some of the threading dislocations generated by lattice-mismatch between the Ge wafer and InP cell so they would be harmlessly confined in this grading layer. The best InP/Ge cell was independently measured by NASA-Lewis with a one-sun 25 C AMO efficiently measured by NASA-Lewis with a one-circuit photocurrent 22.6 mA/sq cm. We believe this is the first published report of an InP cell grown on a Ge wafer. Why get excited over a 9 percent InP/Ge cell? If we look at the cell weight and efficiency, a 9 percent InP cell on an 8 mil Ge wafer has about the same cell power density, 118 W/kg (BOL), as the best InP cell ever made, a 19 percent InP cell on an 18 mil InP wafer, because of the lighter Ge wafer weight. As cell panel materials become lighter, the cell weight becomes more important, and the advantage of lightweight cells to the panel power density becomes more important. In addition, although InP/Ge cells have a low beginning-of-life (BOL) efficiency due to dislocation defects, the InP/Ge cells are very radiation hard (end-of-life power similar to beginning-of-life). We have irradiated an InP/Ge cell with alpha particles to an equivalent fluence of 1.6 x 10(exp 16) 1 MeV electrons/sq cm and the efficiency is still 83 percent of its BOL value. At this fluence level, the power output of these InP/Ge cells matches the GaAs/Ge cell data tabulated in the JPL handbook. Data are presented indicating InP/Ge has more power output than GaAs/Ge cells at fluences in excess of this value.

Wojtczuk, Steven; Vernon, Stanley; Burke, Edward A.

1994-09-01

355

Alveolar Epithelial Cell Injury Due to Zinc Oxide Nanoparticle Exposure  

PubMed Central

Rationale: Although inhalation of zinc oxide (ZnO) nanoparticles (NPs) is known to cause systemic disease (i.e., metal fume fever), little is known about mechanisms underlying injury to alveolar epithelium. Objectives: Investigate ZnO NP–induced injury to alveolar epithelium by exposing primary cultured rat alveolar epithelial cell monolayers (RAECMs) to ZnO NPs. Methods: RAECMs were exposed apically to ZnO NPs or, in some experiments, to culture fluid containing ZnCl2 or free Zn released from ZnO NPs. Transepithelial electrical resistance (RT) and equivalent short-circuit current (IEQ) were assessed as functions of concentration and time. Morphologic changes, lactate dehydrogenase release, cell membrane integrity, intracellular reactive oxygen species (ROS), and mitochondrial activity were measured. Measurements and Main Results: Apical exposure to 176 ?g/ml ZnO NPs decreased RT and IEQ of RAECMs by 100% over 24 hours, whereas exposure to 11 ?g/ml ZnO NPs had little effect. Changes in RT and IEQ caused by 176 ?g/ml ZnO NPs were irreversible. ZnO NP effects on RT yielded half-maximal concentrations of approximately 20 ?g/ml. Apical exposure for 24 hours to 176 ?g/ml ZnO NPs induced decreases in mitochondrial activity and increases in lactate dehydrogenase release, permeability to fluorescein sulfonic acid, increased intracellular ROS, and translocation of ZnO NPs from apical to basolateral fluid (most likely across injured cells and/or damaged paracellular pathways). Conclusions: ZnO NPs cause severe injury to RAECMs in a dose- and time-dependent manner, mediated, at least in part, by free Zn released from ZnO NPs, mitochondrial dysfunction, and increased intracellular ROS.

Kim, Yong Ho; Fazlollahi, Farnoosh; Kennedy, Ian M.; Yacobi, Nazanin R.; Hamm-Alvarez, Sarah F.; Borok, Zea; Kim, Kwang-Jin; Crandall, Edward D.

2010-01-01

356

High efficiency amorphous silicon germanium solar cells  

Microsoft Academic Search

We report high-efficiency single-junction a-SiGe n-i-p solar cells deposited using rf PECVD on stainless steel (SS) substrates coated with metal\\/ZnO back-reflector (BR). The initial and stabilized active-area efficiencies have been improved to 12.5-13.0% and 10.4%, respectively, for 0.25 cm2 a-SiGe cells. The achievement of single-junction cells with such high efficiencies, equivalent to those for the state-of-the-art triple-junction solar cells, are

X. Liao; W. Du; X. Yang; H. Povolny; X. Xiang; X. Deng

2005-01-01

357

Ethambutol-induced toxicity is mediated by zinc and lysosomal membrane permeabilization in cultured retinal cells  

SciTech Connect

Ethambutol, an efficacious antituberculosis agent, can cause irreversible visual loss in a small but significant fraction of patients. However, the mechanism of ocular toxicity remains to be established. We previously reported that ethambutol caused severe vacuole formation in cultured retinal cells, and that the addition of zinc along with ethambutol aggravated vacuole formation whereas addition of the cell-permeable zinc chelator, N,N,N',N'-tetrakis (2-pyridylmethyl) ethylenediamine (TPEN), reduced vacuole formation. To investigate the origin of vacuoles and to obtain an understanding of drug toxicity, we used cultured primary retinal cells from newborn Sprague-Dawley rats and imaged ethambutol-treated cells stained with FluoZin-3, zinc-specific fluorescent dye, under a confocal microscope. Almost all ethambutol-induced vacuoles contained high levels of labile zinc. Double staining with LysoTracker or MitoTracker revealed that almost all zinc-containing vacuoles were lysosomes and not mitochondria. Intracellular zinc chelation with TPEN markedly blocked both vacuole formation and zinc accumulation in the vacuole. Immunocytochemistry with antibodies to lysosomal-associated membrane protein-2 (LAMP-2) and cathepsin D, an acid lysosomal hydrolase, disclosed lysosomal activation after exposure to ethambutol. Immunoblotting after 12 h exposure to ethambutol showed that cathepsin D was released into the cytosol. In addition, cathepsin inhibitors attenuated retinal cell toxicity induced by ethambutol. This is consistent with characteristics of lysosomal membrane permeabilization (LMP). TPEN also inhibited both lysosomal activation and LMP. Thus, accumulation of zinc in lysosomes, and eventual LMP, may be a key mechanism of ethambutol-induced retinal cell death.

Chung, Hyewon; Yoon, Young Hee [Department of Ophthalmology, Asan Medical Center, University of Ulsan, College of Medicine, 388-1 Pungnab-dong, Songpa-gu, Seoul, 138-736 (Korea, Republic of); Hwang, Jung Jin [Institute for Innovative Cancer Research, Asan Medical Center, University of Ulsan, College of Medicine, Seoul (Korea, Republic of); Cho, Kyung Sook [Department of Ophthalmology, Asan Medical Center, University of Ulsan, College of Medicine, 388-1 Pungnab-dong, Songpa-gu, Seoul, 138-736 (Korea, Republic of); Koh, Jae Young [NRL Neural Injury Research Center and the Department of Neurology, Asan Medical Center, University of Ulsan, College of Medicine, Seoul (Korea, Republic of); Kim, June-Gone [Department of Ophthalmology, Asan Medical Center, University of Ulsan, College of Medicine, 388-1 Pungnab-dong, Songpa-gu, Seoul, 138-736 (Korea, Republic of)], E-mail: junekim@amc.seoul.kr

2009-03-01

358

Nanoparticle Solar Cell Final Technical Report  

SciTech Connect

The purpose of this work was to demonstrate all-inorganic nanoparticle-based solar cells with photovoltaic performance extending into the near-IR region of the solar spectrum as a pathway towards improving power conversion efficiencies. The field of all-inorganic nanoparticle-based solar cells is very new, with only one literature publication in the prior to our project. Very little is understood regarding how these devices function. Inorganic solar cells with IR performance have previously been fabricated using traditional methods such as physical vapor deposition and sputtering, and solution-processed devices utilizing IR-absorbing organic polymers have been investigated. The solution-based deposition of nanoparticles offers the potential of a low-cost manufacturing process combined with the ability to tune the chemical synthesis and material properties to control the device properties. This work, in collaboration with the Sue Carter research group at the University of California, Santa Cruz, has greatly expanded the knowledge base in this field, exploring multiple material systems and several key areas of device physics including temperature, bandgap and electrode device behavior dependence, material morphological behavior, and the role of buffer layers. One publication has been accepted to Solar Energy Materials and Solar Cells pending minor revision and another two papers are being written now. While device performance in the near-IR did not reach the level anticipated at the beginning of this grant, we did observe one of the highest near-IR efficiencies for a nanoparticle-based solar cell device to date. We also identified several key parameters of importance for improving both near-IR performance and nanoparticle solar cells in general, and demonstrated multiple pathways which showed promise for future commercialization with further research.

Breeze, Alison, J; Sahoo, Yudhisthira; Reddy, Damoder; Sholin, Veronica; Carter, Sue

2008-06-17

359

Role of a disperse carbon interlayer on the performances of tandem a-Si solar cells  

NASA Astrophysics Data System (ADS)

We report the effect of a disperse carbon interlayer between the n-a-Si:H layer and an aluminium zinc oxide (AZO) back contact on the performance of amorphous silicon solar cells. Carbon was incorporated to the AZO film as revealed by x-ray photoelectron spectroscopy and energy-dispersive x-ray analysis. Solar cells fabricated on glass substrates using AZO in the back contact performed better when a disperse carbon interlayer was present in their structure. They exhibited an initial efficiency of 11%, open-circuit voltage Voc = 1.6 V, short-circuit current JSC = 11 mA cm-2 and a filling factor of 63%, that is, a 10% increase in the JSC and 20% increase in the efficiency compared to a standard solar cell.

Araújo, Andreia; Barros, Raquel; Mateus, Tiago; Gaspar, Diana; Neves, Nuno; Vicente, António; Filonovich, Sergej A.; Barquinha, Pedro; Fortunato, Elvira; Ferraria, Ana M.; Botelho do Rego, Ana M.; Bicho, Ana; Águas, Hugo; Martins, Rodrigo

2013-08-01

360

Optimization of transparent and reflecting electrodes for amorphous-silicon solar cells. Final subcontract report, 1 May 1991--30 April 1994  

SciTech Connect

Fluorine-doped zinc oxide was shown to have the lowest absorption loss of any of the known transparent conductors. An apparatus was constructed to deposit textured, transparent, conductive, fluorine-doped zinc oxide layers with uniform thickness over a 10 cm by 10 cm area, using inexpensive, high-productivity atmospheric pressure chemical vapor deposition. Amorphous silicon solar cells grown on these textured films show very high peak quantum efficiencies (over 90%). However, a significant contact resistance develops at the interface between the amorphous silicon and the zinc oxide. Transparent, conductive gallium-doped zinc oxide films were grown by APCVD at a low enough temperature (260{degree}C) to be deposited on amorphous silicon as a final conductive back contact to solar cells. A quantum-mechanical theory of bonding was developed and applied to some metal oxides; it forms a basis for understanding TCO structures and the stability of their interfaces with silicon.

Gordon, R.G.; Hu, J.; Lacks, D.; Musher, J.; Thornton, J.; Liang, H. [Harvard Univ., Cambridge, MA (United States)

1994-07-01

361

A silicon/zinc 2,9,16,23-tetraaminophthalocyanine coaxial core-shell nanowire array as an efficient solar hydrogen generation photocatalyst  

NASA Astrophysics Data System (ADS)

In this work, we have demonstrated that a silicon nanowire (SiNW) array can be an efficient visible light photocatalyst for hydrogen generation after being modified by the 2,9,16,23-tetraaminophthalocyanine of zinc (ZnTAPc). A photoelectrochemical (PEC) cell employing a ZnTAPc modified SiNW array as photoanode was found to be able to effectively produce hydrogen at a rate of 13 µmol (cm2 h)-1 under 100 mw cm-2 irradiation from a xenon lamp. It is believed that the loading of ZnTAPc can enhance the efficiency of hydrogen generation and the stability of the SiNW array. This demonstrates that the ZnTAPc modified SiNW is a promising material for solar hydrogen generation.

Liu, Zhen; Wang, Hui; Ou, Xue-Mei; Lee, Chun-Sing; Li, Fan; Zhang, Xiao-Hong

2012-05-01

362

Quantum molecular dynamics simulations of hydrogen production and solar cells  

NASA Astrophysics Data System (ADS)

The global energy crisis presents two major challenges for scientists around the world: Producing cleaner energy which is sustainable for the environment; And improving the efficiency of energy production as well as consumption. It is crucial and yet elusive to understand the atomistic mechanisms and electronic properties, which are needed in order to tackle those challenges. Quantum molecular dynamics simulations and nonadiabatic quantum molecular dynamics are two of the dominant methods used to address the atomistic and electronic properties in various energy studies. This dissertation is an ensemble of three studies in energy research: (1) Hydrogen production from the reaction of aluminum clusters with water to provide a renewable energy cycle; (2) The photo-excited charge transfer and recombination at a quaterthiophene/zinc oxide interface to improve the power conversion efficiency of hybrid poly(3-hexylthiophene) (P3HT) /ZnO solar cells; and (3) the charge transfer at a rubrene/C60 interface to understand why phenyl groups in rubrene improve the performance of rubrene/C60 solar cells.

Mou, Weiwei

363

Thin-Film Technology in Intermediate Band Solar Cells: Advanced Concepts for Chalcopyrite Solar Cells  

NASA Astrophysics Data System (ADS)

Combining the two key factors of high performance and low cost into a single solar cell is the major challenge of research on photovoltaics. It is not easy to conceive a practical approach to such a device if not based on thin-film technology. Yet, it appears equally clear that current thin-film solar cells must upgrade their performance by some means in order to meet satisfactory energy conversion efficiencies. The incorporation of novel photovoltaic concepts, particularly the intermediate band solar cell, into thin-film technologies is expected to cross-fertilize both fields. In this chapter, we will outline the potential benefits ofthin-film intermediate band solar cells (TF-IBSC) and describe two different approaches toward its practical implementation. Particular attention will be devoted to devices based on chalcopyrite absorbers, currently leading the efficiency records of thin-film solar cells, and characterized by material properties well suited for this purpose.

Marrón, David Fuertes

364

A systematic review of aluminium phosphide poisoning.  

PubMed

Every year, about 300,000 people die because of pesticide poisoning worldwide. The most common pesticide agents are organophosphates and phosphides, aluminium phosphide (AlP) in particular. AlP is known as a suicide poison that can easily be bought and has no effective antidote. Its toxicity results from the release of phosphine gas as the tablet gets into contact with moisture. Phosphine gas primarily affects the heart, lungs, gastrointestinal tract, and kidneys. Poisoning signs and symptoms include nausea, vomiting, restlessness, abdominal pain, palpitation, refractory shock, cardiac arrhythmias, pulmonary oedema, dyspnoea, cyanosis, and sensory alterations. Diagnosis is based on clinical suspicion, positive silver nitrate paper test to phosphine, and gastric aspirate and viscera biochemistry. Treatment includes early gastric lavage with potassium permanganate or a combination with coconut oil and sodium bicarbonate, administration of charcoal, and palliative care. Specific therapy includes intravenous magnesium sulphate and oral coconut oil. Moreover, acidosis can be treated with early intravenous administration of sodium bicarbonate, cardiogenic shock with fluid, vasopresor, and refractory cardiogenic shock with intra-aortic baloon pump or digoxin. Trimetazidine may also have a useful role in the treatment, because it can stop ventricular ectopic beats and bigeminy and preserve oxidative metabolism. This article reviews the epidemiological, toxicological, and clinical/pathological aspects of AlP poisoning and its management. PMID:22450207

Mehrpour, Omid; Jafarzadeh, Mostafa; Abdollahi, Mohammad

2012-03-01

365

Zinc uptake into endothelial cells involves a carrier mediated component  

SciTech Connect

The mechanism of zinc (Zn) uptake by endothelial cells was examined. Bovine pulmonary endothelial cells were grown to a confluent monolayer in T-25 flasks with minimum essential medium (MEM) containing 10% fetal bovine serum. Zn uptake was studied by replacing the growth medium with experimental media of MEM, 14% EDTA dialyzed serum, and 250 nCi {sup 65}Zn/mL. The transport mechanism was studied by manipulating the composition of the experimental media and measuring the accumulation of {sup 65}Zn by the cells during a 10 min incubation period at 37C, 90% relative humidity, and 5% CO{sub 2}. The rate of Zn uptake increased as the Zn concentration in the media increased from 1 to 26 {mu}M. The data were described by a rectangular hyperbola with V{sub max} = 27.2 {plus minus} 0.84 pmoles Zn and K{sub m} = 4.1 {plus minus} 0.46 {mu}M Zn. The mechanism was studied further with 6 {mu}M added Zn (ZnCl{sub 2}) in the experimental media. Zn uptake was temperature dependent; the rate was less than 6C than at 24C, which was less than at 33C. The Zn uptake rate was reduced by the metabolic inhibitors iodoacetate, sodium fluoride, and N-ethylmaleimide. Cadmium competitively inhibited Zn uptake; copper and manganese had no effect. Increasing the concentration of albumin tin the media reduced the Zn uptake rate over the range from 0 to 40 {mu}M albumin in the media reduced the Zn uptake rate over the range from 0 to 40 {mu}M albumin, but not at 50 {mu}M albumin, with 10 {mu}M Zn. The addition of Zn binding ligands decreased the Zn uptake rate in the absence of serum, but increased the rate when serum was present. These results demonstrate that Zn uptake into endothelial cells is facilitated by a transporter possessing a recognition site that is saturable and at least partially energy dependent. Additionally, the uptake rate apparently is influenced by the ligand to which Zn is bound in the extracellular fluid.

Bobilya, D.J.; Briske-Anderson, M.; Reeves, P.G. (USDA-ARS Human Nutrition Center, Grand Forks, ND (United States))

1991-03-15

366

Glass-Si Heterojunction Solar Cells.  

National Technical Information Service (NTIS)

Measurements on SnO2/n-Si heterojunction solar cells indicate the electron affinity of SnO2 about 0.85 eV greater than of Si. The principal dark current mechanism is electron emission; the operation is evidently similar to Schottky barrier cells. Rapid de...

R. L. Anderson G. Kent

1975-01-01

367

High-efficiency concentrator silicon solar cells  

SciTech Connect

This report presents results from extensive process development in high-efficiency Si solar cells. An advanced design for a 1.56-cm{sup 2} cell with front grids achieved 26% efficiency at 90 suns. This is especially significant since this cell does not require a prismatic cover glass. New designs for simplified backside-contact solar cells were advanced from a status of near-nonfunctionality to demonstrated 21--22% for one-sun cells in sizes up to 37.5 cm{sup 2}. An efficiency of 26% was achieved for similar 0.64-cm{sup 2} concentrator cells at 150 suns. More fundamental work on dopant-diffused regions is also presented here. The recombination vs. various process and physical parameters was studied in detail for boron and phosphorous diffusions. Emitter-design studies based solidly upon these new data indicate the performance vs design parameters for a variety of the cases of most interest to solar cell designers. Extractions of p-type bandgap narrowing and the surface recombination for p- and n-type regions from these studies have a generality that extends beyond solar cells into basic device modeling. 68 refs., 50 figs.

Sinton, R.A.; Cuevas, A.; King, R.R.; Swanson, R.M. (Stanford Univ., CA (USA). Solid-State Electronics Lab.)

1990-11-01

368

Thin-Film Amorphorus Silicon Solar Cells.  

National Technical Information Service (NTIS)

The research programme on amorphous silicon solar cells with the structure Ni/TiOx/undoped amorphous silicon/'n+' amorphous silicon/stainless steel, was divided into three phases, the target being an 8% efficient 1 cm2 cell. It dealt with the growth of am...

R. J. Holwill J. McGill F. Riddoch P. Robinson S. D. Smith

1982-01-01

369

Automatic laser scanner for solar cells  

SciTech Connect

An instrument is described which controls a two-mirror scanning arrangement to raster a laser beam on a large-area solar cell. The short circuit current thus produced is plotted on an X--Y recorder, or recorded on a storage oscilloscope to study the spatial inhomogeneities of the cell.

Khanna, V.; Sastry, O.S.; Mukerjee, A.K.; Chopra, K.L.

1984-10-01

370

Thin Film Solar Cells for Terrestrial Applications.  

National Technical Information Service (NTIS)

The goals of the project are to develop a terrestrial version of the CdS thin film solar cell that is demonstrably amenable to low cost mass production, and to establish data on the lifetime of such cells under the expected conditions of terrestrial use. ...

F. A. Shirland W. J. Biter E. W. Greeneigh T. P. Brody

1975-01-01

371

Recovery of Metal Values from Spent Zinc-Carbon Dry Cell Batteries  

NASA Astrophysics Data System (ADS)

Spent zinc-carbon dry cell batteries were characterized in the process of recovery of metal values. Zinc, manganese and steel were the major metallic materials constituting 63 % of the weight of spent batteries. Different components of the spent batteries were separately processed to extract the metallic values. A maximum of 92 % of total amount of zinc contained in the anodes could be extracted with a purity of over 99.0 % from the anodes by heating at 600 °C for 10 min in presence of 12 % NH4Cl flux. Spent electrolyte paste containing manganese and zinc as major metallic elements, was leached in sulfuric acid solution in presence of hydrogen peroxide as a reducing agent. The optimum condition for leaching was found to be concentration of sulfuric acid: 2.5 M, concentration of hydrogen peroxide: 10 %, temperature: 60 °C, stirring speed: 600 rpm and solid/liquid ratio 1:12. A maximum of 88 % manganese contained in the paste could be dissolved within 27 min of leaching under the optimized conditions. Dissolution of zinc under the same conditions was 97 %. A maximum of 69.89 % of manganese and 83.29 % of zinc contained in the leach liquor could be precipitated in the form of manganese carbonate and zinc oxalate.

Khan, Majharul Haque; Gulshan, Fahmida; Kurny, A. S. W.

2013-04-01

372

Effect of Zinc and Nitric Oxide on Monocyte Adhesion to Endothelial Cells under Shear Stress  

PubMed Central

This study describes the effect of zinc on monocyte adhesion to endothelial cells under different shear stress regimens, which may trigger atherogenesis. Human umbilical vein endothelial cells were exposed to steady shear stress (15 dynes/cm2 or 1 dyne/cm2) or reversing shear stress (time average 1 dyne/cm2) for 24 hours. In all shear stress regimes, zinc deficiency enhanced THP-1 cell adhesion, while heparinase III reduced monocyte adhesion following reversing shear stress exposure. Unlike other shear stress regimes, reversing shear stress alone enhanced monocyte adhesion, which may be associated with increased H2O2 and superoxide together with relatively low levels of nitric oxide (NO) production. L-NG-Nitroarginine methyl ester (L-NAME) treatment increased monocyte adhesion under 15 dynes/cm2 and under reversing shear stress. After reversing shear stress monocyte adhesion dramatically increased with heparinase III treatment followed by a zinc scavenger. Static culture experiments supported the reduction of monocyte adhesion by zinc following endothelial cell cytokine activation. These results suggest that endothelial cell zinc levels are important for the inhibition of monocyte adhesion to endothelial cells, and may be one of the key factors in the early stages of atherogenesis.

Lee, Sungmun; Eskin, Suzanne G.; Shah, Ankit K.; Schildmeyer, Lisa A.; McIntire, Larry V.

2011-01-01

373

Characterization of ZnS-layer-inserted bulk-heterojunction organic solar cells by ac impedance spectroscopy  

Microsoft Academic Search

A fluorine-doped tin oxide (FTO)\\/zinc sulfide (ZnS)\\/[6,6]-phenyl C61 butyric acid methyl ester (PCBM): regioregular poly(3-hexylthiophene) (P3HT)\\/poly(3,4-ethylenedioxylenethiophene): poly(4-styrene sulfonic acid) (PEDOT:PSS)\\/Au type organic solar cell (FTO\\/ZnS\\/PCBM:P3HT\\/PEDOT:PSS\\/Au, ZnS cell) with a 1 cm2 active area was first developed using transparent ZnS prepared on a FTO electrode by a chemical bath deposition method. The ZnS inserted solar cells were investigated by photocurrent-voltage (I-V)

Takayuki Kuwabara; Masayuki Nakamoto; Yoshitaka Kawahara; Takahiro Yamaguchi; Kohshin Takahashi

2009-01-01

374

Investigation of polycrystalline thin film CuInSeâ solar cells based on ZnSe windows. Annual subcontract report, 15 February, 1993--14 February, 1994  

Microsoft Academic Search

This report concerns studies of CIS solar cells based on ZnSe window layers. ZnSe\\/CIS devices are fabricated by growing ZnSe films by MOCVD onto Siemens CIS and graded absorber substrates. ZnSe films are grown by reacting HâSe with a zinc adduct. ZnSe\\/CIS heterojunctions have been studied by depositing transparent aluminum contacts onto ZnSe. These studies indicate that ZnSe\\/CIS solar cells

1995-01-01

375

Surface plasmon enhanced silicon solar cells  

NASA Astrophysics Data System (ADS)

Thin-film solar cells have the potential to significantly decrease the cost of photovoltaics. Light trapping is particularly critical in such thin-film crystalline silicon solar cells in order to increase light absorption and hence cell efficiency. In this article we investigate the suitability of localized surface plasmons on silver nanoparticles for enhancing the absorbance of silicon solar cells. We find that surface plasmons can increase the spectral response of thin-film cells over almost the entire solar spectrum. At wavelengths close to the band gap of Si we observe a significant enhancement of the absorption for both thin-film and wafer-based structures. We report a sevenfold enhancement for wafer-based cells at ?=1200 nm and up to 16-fold enhancement at ?=1050 nm for 1.25 ?m thin silicon-on-insulator (SOI) cells, and compare the results with a theoretical dipole-waveguide model. We also report a close to 12-fold enhancement in the electroluminescence from ultrathin SOI light-emitting diodes and investigate the effect of varying the particle size on that enhancement.

Pillai, S.; Catchpole, K. R.; Trupke, T.; Green, M. A.

2007-05-01

376

Towards highly efficient solar cells  

NASA Astrophysics Data System (ADS)

Suntech Power is the world's largest producer of solar panels and has delivered more than 20 million photovoltaic panels to more than 80 countries around the globe. Nature Photonics spoke with Stuart Wenham, chief technology officer at Suntech Power, to find out more about its activities and visions.

2012-03-01

377

Nanocrystal-polymer solar cells  

Microsoft Academic Search

The ability to structure materials on a nanometer dimension enables the processes of solar energy conversion to be optimized at their most fundamental length scale. In semiconducting nanocrystals, optical absorption and electrical transport can be tailored by changing their radius and length, respectively. The unique features of quantum confinement and shape manipulation characteristic for inorganic nanocrystals can be utilized to

Wendy Uyen Huynh

2002-01-01

378

Fill factor in organic solar cells.  

PubMed

The fill factor (FF) is an important parameter that determines the power conversion efficiency of an organic solar cell. There are several factors that can significantly influence FF, and these factors interact with each other very intricately. Due to this reason, a deep understanding of FF is quite difficult. Based on the three fundamental elements in the solar cell equivalent circuit, namely series resistance, shunt resistance and diode, we reviews the research progress in understanding on FF in organic solar cells. Physics lying behind the often-observed undesirable S-shaped J-V curves is also summarized. This paper aims to give a brief and comprehensive summary on FF from a fundamental point of view. PMID:23652780

Qi, Boyuan; Wang, Jizheng

2013-05-07

379

Solar cell parameter extraction using genetic algorithms  

NASA Astrophysics Data System (ADS)

In this paper, a technique based on genetic algorithms is proposed for improving the accuracy of solar cell parameters extracted using conventional techniques. The approach is based on formulating the parameter extraction as a search and optimization problem. Current-voltage data used were generated by simulating a two-diode solar cell model of specified parameters. The genetic algorithm search range that simulates the error in the extracted parameters was varied from ±5 to ±100% of the specified parameter values. Results obtained show that for a simulated error of ±5% in the solar cell model values, the deviation of the extracted parameters varied from 0.1 to 1% of the specified values. Even with a simulated error of as high as ±100%, the resulting deviation only varied from 2 to 36%. The performance of this technique is also shown to surpass the quasi-Newton method, a calculus-based search and optimization algorithm.

Jervase, Joseph A.; Bourdoucen, Hadj; Al-Lawati, Ali

2001-11-01

380

Investigation of polycrystalline thin-film CuInSe2 solar cells based on ZnSe windows  

Microsoft Academic Search

Investigations of ZnSe\\/CIS solar cells are being carried out in an effort to improve the efficiencies CIS cells and to determine if ZnSe is a viable alternative to CdS as a window material. MOCVD growth of ZnSe is accomplished in a SPIRE 500XT reactor housed in the Electronic Materials Laboratory at WSU Tri-Cities by reacting a zinc adduct with H2Se.

L. C. Olsen

1994-01-01

381

The characteristics of solar cells exposed to ?-radiation  

Microsoft Academic Search

We have investigated the characteristics of solar cells exposed to ?-radiation from the standpoint of developing such gamma cells utilizing nuclear spent fuels. The examination was performed for three representative types of solar cells, i.e. amorphous, monocrystalline and polycrystalline types. These solar cells were remotely irradiated using a highly intensive 60Co ?-source instead of spent fuels, and the induced current

Norikazu Horiuchi; Koichi Taniguchi; Masaki Kamiki; Takashi Kondo; Masanori Aritomi

1997-01-01

382

A zinc-resistant human epithelial cell line is impaired in cadmium and manganese import  

SciTech Connect

A human epithelial cell line (HZR) growing with high zinc concentrations has been analyzed for its ability to sustain high cadmium concentrations. Exposure to up to 200 {mu}M of cadmium acetate for 24 h hardly impacted viability, whereas most of parental HeLa cells were killed by less than 10 {mu}M of cadmium. Upon challenge by 35 fold higher cadmium concentrations than HeLa cells, HZR cells did not display increased DNA damage, increased protein oxidation, or changed intracellular cadmium localization. Rather, the main cause of resistance against cadmium was by avoiding cadmium entry into cells, which differs from that against zinc as the latter accumulates inside cells. The zinc-resistant phenotype of these cells was shown to also impair extracellular manganese uptake. Manganese and cadmium competed for entry into HeLa cells. Probing formerly identified cadmium or manganese transport systems in different animal cells did not evidence any significant change between HeLa and HZR cells. These results reveal zinc adaptation influences manganese and cadmium cellular traffic and they highlight previously unknown connections among homeostasis of divalent metals.

Rousselet, Estelle [CEA, DSV, IRTSV, Laboratoire de Chimie et Biologie des Metaux, Grenoble (France)]|[LCBM, CNRS UMR5249, Grenoble (France); Universite Joseph Fourier, Grenoble (France); Richaud, Pierre [CEA, DSV, IBEB, SBVME, LB3M, Saint-Paul-lez-Durance (France)]|[LB3M, CNRS UMR 6191, Saint-Paul-lez-Durance (France)]|[Universite Aix-Marseille (France); Douki, Thierry; Chantegrel, Jocelyne Garcia; Favier, Alain [Universite Joseph Fourier, Grenoble (France)]|[CEA, DSM, INaC/SCIB, Laboratoire 'Lesions des Acides Nucleiques', Grenoble (France); Bouron, Alexandre [CEA, DSV, IRTSV, Laboratoire de Chimie et Biologie des Metaux, Grenoble (France)]|[LCBM, CNRS UMR5249, Grenoble (France)]|[Universite Joseph Fourier, Grenoble (France); Moulis, Jean-Marc [CEA, DSV, IRTSV, Laboratoire de Chimie et Biologie des Metaux, Grenoble (France)]|[LCBM, CNRS UMR5249, Grenoble (France)]|[Universite Joseph Fourier, Grenoble (France)], E-mail: jean-marc.moulis@cea.fr

2008-08-01

383

Zinc sulfide in intestinal cell granules of Ancylostoma caninum adults  

SciTech Connect

A source of confusion has existed since the turn of the century about the reddish brown, weakly birefringent 'sphaerocrystals' located in the intestines of strongyle nematodes, Strongylus and Ancylostoma. X-ray diffraction and energy dispersive spectrometric analyses were used for accurate determination of the crystalline order and elemental composition of the granules in the canine hookworm Ancylostoma caninum. The composition of the intestinal pigmented granules was identified unequivocally as zinc sulfide. It seems most probable that the granules serve to detoxify high levels of metallic ions (specifically zinc) present due to the large intake of host blood.

Gianotti, A.J.; Clark, D.T.; Dash, J. (Portland State Univ., OR (USA))

1991-04-01

384

Cobalt chloride speciation, mechanisms of cytotoxicity on human pulmonary cells, and synergistic toxicity with zinc.  

PubMed

Cobalt is used in numerous industrial sectors, leading to occupational diseases, particularly by inhalation. Cobalt-associated mechanisms of toxicity are far from being understood and information that could improve knowledge in this area is required. We investigated the impact of a soluble cobalt compound, CoCl(2)·6H(2)O, on the BEAS-2B lung epithelial cell line, as well as its impact on metal homeostasis. Cobalt speciation in different culture media, in particular soluble and precipitated cobalt species, was investigated via theoretical and analytical approaches. The cytotoxic effects of cobalt on the cells were assessed. Upon exposure of BEAS-2B cells to cobalt, intracellular accumulation of cobalt and zinc was demonstrated using direct in situ microchemical analysis based on ion micro-beam techniques and analysis after cell lysis by inductively coupled plasma mass spectrometry (ICP-MS). Microchemical imaging revealed that cobalt was rather homogeneously distributed in the nucleus and in the cytoplasm whereas zinc was more abundant in the nucleus. The modulation of zinc homeostasis led to the evaluation of the effect of combined cobalt and zinc exposure. In this case, a clear synergistic increase in toxicity was observed as well as a substantial increase in zinc content within cells. Western blots performed under the same coexposure conditions revealed a decrease in ZnT1 expression, suggesting that cobalt could inhibit zinc release through the modulation of ZnT1. Overall, this study highlights the potential hazard to lung function, of combined exposure to cobalt and zinc. PMID:23505636

Bresson, Carole; Darolles, Carine; Carmona, Asuncion; Gautier, Céline; Sage, Nicole; Roudeau, Stéphane; Ortega, Richard; Ansoborlo, Eric; Malard, Véronique

2013-02-01

385

ANALYSIS OF THE WATER-SPLITTING CAPABILITIES OF GALLIUM INDIUM PHOSPHIDE NITRIDE (GaInPN)  

SciTech Connect

With increasing demand for oil, the fossil fuels used to power society’s vehicles and homes are becoming harder to obtain, creating pollution problems and posing hazard’s to people’s health. Hydrogen, a clean and effi cient energy carrier, is one alternative to fossil fuels. Certain semiconductors are able to harness the energy of solar photons and direct it into water electrolysis in a process known as photoelectrochemical water-splitting. P-type gallium indium phosphide (p-GaInP2) in tandem with GaAs is a semiconductor system that exhibits water-splitting capabilities with a solar-tohydrogen effi ciency of 12.4%. Although this material is effi cient at producing hydrogen through photoelectrolysis it has been shown to be unstable in solution. By introducing nitrogen into this material, there is great potential for enhanced stability. In this study, gallium indium phosphide nitride Ga1-yInyP1-xNx samples were grown using metal-organic chemical vapor deposition in an atmospheric-pressure vertical reactor. Photocurrent spectroscopy determined these materials to have a direct band gap around 2.0eV. Mott-Schottky analysis indicated p-type behavior with variation in fl atband potentials with varied frequencies and pH’s of solutions. Photocurrent onset and illuminated open circuit potential measurements correlated to fl atband potentials determined from previous studies. Durability analysis suggested improved stability over the GaInP2 system.

Head, J.; Turner, J.

2007-01-01

386

Loss of pluripotency in human embryonic stem cells directly correlates with an increase in nuclear zinc.  

SciTech Connect

The pluripotency of human embryonic stem cells (hESCs) is important to investigations of early development and to cell replacement therapy, but the mechanism behind pluripotency is incompletely understood. Zinc has been shown to play a key role in differentiation of non-pluripotent cell types, but here its role in hESCs is directly examined. By mapping the distribution of metals in hESCs at high resolution by x-ray fluorescence microprobe (XFM) and by analyzing subcellular metal content, we have found evidence that loss of pluripotency is directly correlated with an increase in nuclear zinc. Zinc elevation not only redefines our understanding of the mechanisms that support pluripotency, but also may act as a biomarker and an intervention point for stem cell differentiation.

Finney, L.; Vogt, S.; Wolford, J. L.; Chishti, Y.; Jin, Q.; Ward, J.; Chen, L. (Biosciences Division); ( XSD)

2010-01-01

387

Illuminating mobile zinc with fluorescence from cuvettes to live cells and tissues.  

PubMed

With the aid of chemoselective sensors, fluorescence microscopy has emerged as an indispensable tool to visualize the distribution and dynamics of various biologically important molecules in live specimens. Motivated by our interest in understanding the chemistry and biology of mobile zinc underlying its physiological and pathological roles, over the past decade, our laboratory has developed an extensive library of zinc fluorescence probes. In this chapter, we provide essential information about our sensor toolbox in order to assist investigators interested to apply our constructs to study various aspects of mobile zinc biology. We illustrate their use with several examples of imaging both exogenous and endogenous mobile zinc in live cells and tissues using various versions of fluorescence microscopy, including confocal and two-photon microscopy. PMID:22289467

Huang, Zhen; Lippard, Stephen J

2012-01-01

388

Multichromophore light harvesting in hybrid solar cells.  

PubMed

A new technologically relevant method for multichromophore sensitizing of hybrid blend solar cells is presented. Two dyes having complementary absorption in the UV-visible regions are individually adsorbed on nanocrystalline TiO(2) powder. These dyed TiO(2) nanoparticles are blended with an organic hole-conductor (HC) Spiro-OMeTAD in desired compositions and applied on a conducting substrate by doctor-blading at room temperature to fabricate multichromophore-sensitized hybrid blend solar cells. The external quantum efficiency (EQE) of the single hybrid layer system fabricated with two dyes, that absorb mainly UV (TPD dye) and visible regions (Ru-TPA-NCS dye), exhibited a clear panchromatic response with the sum of the EQE characteristics of each single dye cell. The first results of a multichromophore-sensitized solid-state solar cell showed J(sc) of 2.1 mA cm(-2), V(oc) of 645 mV, FF of 47% and efficiency of 0.65% at AM 1.5 G, 100 mW cm(-2) illumination intensity. The J(sc) of the multichromophore cell is the sum of the individually dyed solar cells. The process described here is technically very innovative and very simple in procedure. It has potentials to be adopted for panchromatic sensitization using more than two dyes in a single hybrid layer or layer-wise fabrication of a tandem structure at room temperature. PMID:21695348

Bandara, Jayasundera; Willinger, Katja; Thelakkat, Mukundan

2011-06-22

389

Gallium arsenide solar cell radiation damage study  

SciTech Connect

An analysis has been made of electrons and proton damaged GaAs solar cells suitable for use in space. The authors find that although some electrical parametric data and spectral response data are quite similar, the type of damage due to the two types of radiation is different. An I {minus} V analysis model shows that electrons damage the bulk of the cell and its currents relatively more while protons damage the junction of the cell and its voltages more.

Maurer, R.H.; Herbert, G.A.; Kinnison, J.D. (The Johns Hopkins Univ., Applied Physics Lab., Laurel, MD (US)); Meulenberg, A. (COMSAT Lab., Clarksburg, MD (US))

1989-12-01

390

Electroluminescence from CdTe Solar Cells  

NASA Astrophysics Data System (ADS)

We have observed room-temperature electroluminescence (EL) from CdTe/CdS thin film solar cells. The spectral shape of the emission is similar to photoluminescence from the CdTe/CdS junction of the same devices. We attribute the electroluminescence to recombination of injected electrons and holes at the CdTe/CdS interface. The integrated electroluminescence intensity shows super-quadratic dependence on the device current. The EL intensity is shown to decrease after one-sun light soaking. These results demonstrate electroluminescence to be a promising characterization tool for CdTe/CdS solar cells. This work supported by the National Renewable Energy Laboratory (NREL).

Price, K. J.; Vasko, A.; Compaan, A. D.

2002-03-01

391

New UV-enhanced solar blind optical sensors based on monocrystalline zinc sulphide  

Microsoft Academic Search

UV-enhanced monocrystalline zinc sulphide optical sensors with high quantum efficiency have been developed by spray deposition of heavy fluorine-doped tin oxide (FTO) thin films onto the surface of zinc sulphide monocrystals as an alternative to the UV-enhanced high-efficiency silicon photodetectors commonly used in precise radiometric and spectroscopic measurements as well as to new sensors based on SiC and GaN. The

Alexander Malik; Ana Sêco; Elvira Fortunato; Rodrigo Martins

1998-01-01

392

Optimum operating conditions of a solar cell panel and prediction of solar radiation in Sanaa, Yemen  

Microsoft Academic Search

Results of a study of the performance of solar cells under nominal operating conditions in Yemen are reported. The solar cell panel comprised 14 Si cells of .003 sq m surface area each, and was mounted on a rooftop with the solar radiation being measured by a pyranometer. Further monitoring was performed of the panel surface temperature, the ambient air

A. Khogali; M. R. I. Ramadan

1982-01-01

393

Diffused transmission and texture-induced defect with transparent conducting oxide front electrode of amorphous silicon solar cell  

NASA Astrophysics Data System (ADS)

Highly textured transparent conducting front electrode (TFE) can enhance light trapping; however, we observed an improved performance of a solar cell by nanometer level modification of surface texture. A 40 nm thick aluminum doped zinc oxide was sputter deposited at an oblique flux on the textured fluorine doped tin oxide TFE, and a TFE double layer was used for the front electrode of solar cells. The cells fabricated on these modified TFEs exhibited an increased open circuit voltage, enhancement in short circuit current density and an increase in fill factor that reached up to 74% because of reduced series resistance of the cell. The surface texture of the TFE was modified with various angular fluxes of the zinc oxide sputter particle, which shows lower texture-induced-surface defect, higher work function. These are thought to have helped in improving the performance of the thin-film solar cells. However, at a near normal angular flux of the zinc oxide sputter particle, light trapping was observed to have reduced significantly, leading to a significant reduction in current density of the cell.

Park, Hyeongsik; Iftiquar, S. M.; Kim, Hee Won; Lee, Jaehyeong; Le, Anh Huy Tuan; Yi, Junsin

2013-11-01

394

Solar cells incorporating transparent electrodes comprising hazy zinc oxide  

SciTech Connect

This patent describes a photovoltaic device. It comprises a semiconductor layer comprising a compound semiconductor selected from the group consisting of II/VI, III/V, I/III/VI, and II/IV/V compounds; and a transparent conductor layer in contact with the semiconductor layer, wherein the transparent conductor layer comprises hazy ZnO.

Pier, D.N.; Gay, C.F.; Wieting, R.D.; Langeberg, H.J.

1992-01-07

395

Zinc poisoning  

MedlinePLUS

... preservatives, and ointments Rust prevention coatings Vitamin and mineral supplements Zinc chloride Zinc oxide (relatively nonharmful) Zinc acetate Zinc sulfate Heated or burned galvanized metal (releases zinc fumes) ...

396

Luminescent solar concentrators and all-inorganic nanoparticle solar cells for solar energy harvesting  

NASA Astrophysics Data System (ADS)

Increasing energy demand and the parallel increase of greenhouse gas emissions are challenging researchers to find new and cleaner energy sources. Solar energy harvesting is arguably the most promising candidate for replacing fossil-fuel power generation. Photovoltaics are the most direct way of collecting solar energy; cost continues to hinder large-scale implementation of photovoltaics, however. Therefore, alternative technologies that will allow the extraction of solar power, while maintaining the overall costs of fabrication, installation, collection, and distribution low, must be explored. This thesis focuses on the fabrication and testing of two types of devices that step up to this challenge: the luminescent solar concentrator (LSC) and all-inorganic nanoparticle solar cells. In these devices I make use of novel materials, semiconducting polymers and inorganic nanoparticles, both of which have lower costs than the crystalline materials used in the fabrication of traditional photovoltaics. Furthermore, the cost of manufacturing LSCs and the nanoparticle solar cells is lower than the manufacturing cost of traditional optics-based concentrators and crystalline solar cells. An LSC is essentially a slab of luminescent material that acts as a planar light pipe. The LSC absorbs incoming photons and channels fluoresced photons toward appropriately located solar cells, which perform the photovoltaic conversion. By covering large areas with relatively inexpensive fluorescing organic dyes or semiconducting polymers, the area of solar cell needed is greatly reduced. Because semiconducting polymers and quantum dots may have small absorption/emission band overlaps, tunable absorption, and longer lifetimes, they are good candidates for LSC fabrication, promising improvement with respect to laser dyes traditionally used to fabricate LSCs. Here the efficiency of LSCs consisting of liquid solutions of semiconducting polymers encased in glass was measured and compared to the efficiency of LSCs based on small molecule laser dyes and on quantum dots. Factors affecting the optical efficiency of the system such as the luminescing properties of the fluorophors were examined. The experimental results were compared to Monte-Carlo simulations. Our results suggest that commercially available quantum dots cannot serve as viable LSC dyes because of large absorption/emission band overlap and relatively low quantum yield. Materials such as Red F demonstrate that semi-conducting polymers with high quantum yield and small absorption/emission band overlap are good candidates for LSCs. Recently, a solar cell system based purely on CdSe and Cite nanoparticles as the absorbing materials was proposed ans it was suggested that its operational mechanism was that of polymer donor/acceptor systems. Here we present solar cells consisting of a sintered active bilayer of CdSe and PbSe nanoparticles in the structure ITO/CdSe/interlayer/PbSe/Al, where an interlayer of LiF or Al2O3 was found necessary to prevent low shunt resistance from suppressing the photovoltaic behavior. We fabricated unoptimized solar cells with a short-circuit current of 6 mA/cm2, an open-circuit voltage of 0.18 V, and a fill factor of 41%. External quantum efficiency spectra revealed that photons from the infrared portion of the spectrum were not collected, suggesting that the low bandgap PbSe film did not contribute to the photocurrent of the structure despite exhibiting photoconductivity. Other measurements, however, showed that the PbSe film was indeed necessary to produce a photovoltage and transport electrons. Through sintering, the nanoparticle films acquired bandgaps similar to those of the corresponding bulk materials and became more conductive. Because the PbSe films were found to be considerably more conductive than the CdSe ones, we suggest that the PbSe layer is effectively behaving like a low conductivity electrical contact. Therefore, in contrast to the photovoltaics presented in the seminal research on CdSe/Cite solar cells, the CdSe/PbSe solar cell system presented here d

Sholin, Veronica

397

Influence of the indium tin oxide\\/organic interface on open-circuit voltage, recombination, and cell degradation in organic small-molecule solar cells  

Microsoft Academic Search

In this paper we investigate the performance and stability of small-molecule organic solar cells with respect to the indium tin oxide (ITO)\\/organic interface. Different zinc-phthalocyanine (ZnPc)\\/fullerene (C60) cell architectures with and without ITO O2-plasma treatment are compared and tested with respect to their degradation behavior under illumination in inert atmosphere. Photoelectron spectroscopy (UPS and XPS) shows that the O2-plasma treatment

Stefan Schäfer; Andreas Petersen; Thomas A. Wagner; Rolf Kniprath; Dominic Lingenfelser; Achmad Zen; Thomas Kirchartz; Birger Zimmermann; Uli Würfel; Xianjin Feng; Thomas Mayer

2011-01-01

398

Process development for high-efficiency silicon solar cells.  

National Technical Information Service (NTIS)

Fabrication of high-efficiency silicon solar cells in an industrial environment requires a different optimization than in a laboratory environment. Strategies are presented for process development of high-efficiency silicon solar cells, with a goal of sim...

J. M. Gee P. A. Basore M. E. Buck D. S. Ruby W. K. Schubert

1991-01-01

399

Theoretical Quantification of Nonlinear Effects in Silicon Solar Cells.  

National Technical Information Service (NTIS)

An analytic model for the internal quantum efficiency of solar cells is presented. It is especially intended for explanation and quantitative analysis of nonlinear effects in silicon solar cells. The model differs from conventional ones in that it conside...

J. M. Ruiz

1986-01-01

400

Plastic solar cells with engineered interfaces  

NASA Astrophysics Data System (ADS)

We discuss here bulk-heterojunction polymer solar cells with engineered interfaces to achieve desired phase separations (vertical and horizontal), molecule orientations, ohmic contacts, and electronic properties for device performance maximization, and to enhance the device durability by eliminating corrosive interfacial layers. The strategies discussed include development of novel interfacial layers such as self-assembled organic layers and inorganic metal oxide layers, and using inverted cell architectures. Interface engineering leads to optimal active layer morphologies and to polymer ?- orientation, as well as maximum open circuit voltage. Using p-type NiO as the anode hole transporting/electron blocking layer results in dramatically enhanced device performance of P3HT/PCBM polymer solar cells with PCEs up to 5%. Electrical property and surface morphology investigations of NiO elucidate the mechanism for the enhanced performance. Other novel interfacial materials such as self-assembled organic monolayers and graphene oxide (GO) have also been incorporated into polymer solar cells to achieve comparable PCEs with improved device stability. Using ZnO as electron transporting/hole blocking layer and employing an inverted device architecture, polymer solar cells achieve desired molecule ?-orientation and vertical phase separation, therefore extremely high fill factors and promising power conversion efficiencies. In addition to interfacial layer materials, active layer components with state-of-the-art device performance, both polymer and small molecule developed in this laboratory, will also be discussed.

Guo, Xugang; Marks, Tobin J.

2013-03-01

401

An effective interaction potential for gallium phosphide.  

PubMed

An effective interatomic potential consisting of two- and three-body covalent interactions is used here to study the properties of gallium phosphide by molecular dynamics simulations. The many-body interatomic potential accounts for the energy scale, length scale and mechanical properties of GaP. At atmospheric pressure, the calculated melting temperature, linear thermal expansion, vibrational density of states and specific heat are in excellent agreement with experimental results. The structural phase transition induced by hydrostatic pressure at 27 GPa is also in quite good agreement with experimental findings. We also studied the energy of vacancy formation in the GaP lattice and the surface energy, which is in reasonable agreement with experimental data. PMID:21406914

Ribeiro-Silva, C I; Rino, J P; Gonçalves, Luis G V; Picinin, A

2011-01-13

402

Direct band gap wurtzite gallium phosphide nanowires.  

PubMed

The main challenge for light-emitting diodes is to increase the efficiency in the green part of the spectrum. Gallium phosphide (GaP) with the normal cubic crystal structure has an indirect band gap, which severely limits the green emission efficiency. Band structure calculations have predicted a direct band gap for wurtzite GaP. Here, we report the fabrication of GaP nanowires with pure hexagonal crystal structure and demonstrate the direct nature of the band gap. We observe strong photoluminescence at a wavelength of 594 nm with short lifetime, typical for a direct band gap. Furthermore, by incorporation of aluminum or arsenic in the GaP nanowires, the emitted wavelength is tuned across an important range of the visible light spectrum (555-690 nm). This approach of crystal structure engineering enables new pathways to tailor materials properties enhancing the functionality. PMID:23464761

Assali, S; Zardo, I; Plissard, S; Kriegner, D; Verheijen, M A; Bauer, G; Meijerink, A; Belabbes, A; Bechstedt, F; Haverkort, J E M; Bakkers, E P A M

2013-03-18

403

Direct Band Gap Wurtzite Gallium Phosphide Nanowires  

PubMed Central

The main challenge for light-emitting diodes is to increase the efficiency in the green part of the spectrum. Gallium phosphide (GaP) with the normal cubic crystal structure has an indirect band gap, which severely limits the green emission efficiency. Band structure calculations have predicted a direct band gap for wurtzite GaP. Here, we report the fabrication of GaP nanowires with pure hexagonal crystal structure and demonstrate the direct nature of the band gap. We observe strong photoluminescence at a wavelength of 594 nm with short lifetime, typical for a direct band gap. Furthermore, by incorporation of aluminum or arsenic in the GaP nanowires, the emitted wavelength is tuned across an important range of the visible light spectrum (555–690 nm). This approach of crystal structure engineering enables new pathways to tailor materials properties enhancing the functionality.

2013-01-01

404

A review of mathematical modeling of the zinc\\/bromine flow cell and battery  

Microsoft Academic Search

Mathematical models which have been developed to study various aspects of the zinc\\/bromine cell and stack of cells are reviewed. Development of these macroscopic models begins with a material balance, a transport equation which includes a migration term for charged species in an electric field, and an electrode kinetic expression. Various types of models are discussed: partial differential equation models

T. I. Evans; R. E. White

1987-01-01

405

Cycles till failure of silver-zinc cells with competing failure modes - Preliminary data analysis  

Microsoft Academic Search

The data analysis of cycles to failure of silver-zinc electrochemical cells with competing failure modes is presented. The test ran 129 cells through charge-discharge cycles until failure; preliminary data analysis consisted of response surface estimate of life. Batteries fail through low voltage condition and an internal shorting condition; a competing failure modes analysis was made using maximum likelihood estimation for

S. M. Sidik; H. F. Leibecki; J. M. Bozek

1980-01-01

406

Development of a 12 ampere-hour sealed silver-zinc cell for satellite applications  

Microsoft Academic Search

Cells incorporating the latest parameters of the sealed silver-zinc system were designed and cycle tested. Early designs failed after 50 cycles. A poor charge acceptance at high current density was due to electrolyte starvation in the positive compartment. To facilitate the electrolyte diffusion to the positive plates, low-concentration KOH was used. It extended the cycling life of the cells but

Serenyi

1964-01-01

407

In vitro cytotoxicity testing of three zinc metal salts using established fish cell lines  

Microsoft Academic Search

The utilisation of fish cell lines has proven to be a valuable, rapid and cost-effective tool in the ecotoxicological assessment of chemicals and environmental samples. The main objective of this study was to investigate the value of multiple endpoint measurements in evaluating the cytotoxicity of three divalent zinc salts in three established fish cell lines (EPC, CHSE and RTG-2) and

S N?? Shúilleabháin; C. Mothersill; D. Sheehan; N. M O’Brien; J O’ Halloran; F. N. A. M Van Pelt; M Davoren

2004-01-01

408

Multi-junction solar cell device  

DOEpatents

A multi-junction solar cell device (10) is provided. The multi-junction solar cell device (10) comprises either two or three active solar cells connected in series in a monolithic structure. The multi-junction device (10) comprises a bottom active cell (20) having a single-crystal silicon substrate base and an emitter layer (23). The multi-junction device (10) further comprises one or two subsequent active cells each having a base layer (32) and an emitter layer (23) with interconnecting tunnel junctions between each active cell. At least one layer that forms each of the top and middle active cells is composed of a single-crystal III-V semiconductor alloy that is substantially lattice-matched to the silicon substrate (22). The polarity of the active p-n junction cells is either p-on-n or n-on-p. The present invention further includes a method for substantially lattice matching single-crystal III-V semiconductor layers with the silicon substrate (22) by including boron and/or nitrogen in the chemical structure of these layers.

Friedman, Daniel J. (Lakewood, CO); Geisz, John F. (Wheat Ridge, CO)

2007-12-18

409

Polymer-fullerene bulk heterojunction solar cells  

NASA Astrophysics Data System (ADS)

Organic solar cells have the potential to be low-cost and efficient solar energy converters, with a promising energy balance. They are made of carbon-based semiconductors, which exhibit favourable light absorption and charge generation properties, and can be manufactured by low temperature processes such as printing from solvent-based inks, which are compatible with flexible plastic substrates or even paper. In this review, we will present an overview of the physical function of organic solar cells, their state-of-the-art performance and limitations, as well as novel concepts to achieve a better material stability and higher power conversion efficiencies. We will also briefly review processing and cost in view of the market potential.

Deibel, Carsten; Dyakonov, Vladimir

2010-09-01

410

ttm-1 Encodes CDF Transporters That Excrete Zinc from Intestinal Cells of C. elegans and Act in a Parallel Negative Feedback Circuit That Promotes Homeostasis  

PubMed Central

Zinc is an essential metal involved in a wide range of biological processes, and aberrant zinc metabolism is implicated in human diseases. The gastrointestinal tract of animals is a critical site of zinc metabolism that is responsible for dietary zinc uptake and distribution to the body. However, the role of the gastrointestinal tract in zinc excretion remains unclear. Zinc transporters are key regulators of zinc metabolism that mediate the movement of zinc ions across membranes. Here, we identified a comprehensive list of 14 predicted Cation Diffusion Facilitator (CDF) family zinc transporters in Caenorhabditis elegans and demonstrated that zinc is excreted from intestinal cells by one of these CDF proteins, TTM-1B. The ttm-1 locus encodes two transcripts, ttm-1a and ttm-1b, that use different transcription start sites. ttm-1b expression was induced by high levels of zinc specifically in intestinal cells, whereas ttm-1a was not induced by zinc. TTM-1B was localized to the apical plasma membrane of intestinal cells, and analyses of loss-of-function mutant animals indicated that TTM-1B promotes zinc excretion into the intestinal lumen. Zinc excretion mediated by TTM-1B contributes to zinc detoxification. These observations indicate that ttm-1 is a component of a negative feedback circuit, since high levels of cytoplasmic zinc increase ttm-1b transcript levels and TTM-1B protein functions to reduce the level of cytoplasmic zinc. We showed that TTM-1 isoforms function in tandem with CDF-2, which is also induced by high levels of cytoplasmic zinc and reduces cytoplasmic zinc levels by sequestering zinc in lysosome-related organelles. These findings define a parallel negative feedback circuit that promotes zinc homeostasis and advance the understanding of the physiological roles of the gastrointestinal tract in zinc metabolism in animals.

Roh, Hyun Cheol; Collier, Sara; Deshmukh, Krupa; Guthrie, James; Robertson, J. David; Kornfeld, Kerry

2013-01-01

411

ttm-1 encodes CDF transporters that excrete zinc from intestinal cells of C. elegans and act in a parallel negative feedback circuit that promotes homeostasis.  

PubMed

Zinc is an essential metal involved in a wide range of biological processes, and aberrant zinc metabolism is implicated in human diseases. The gastrointestinal tract of animals is a critical site of zinc metabolism that is responsible for dietary zinc uptake and distribution to the body. However, the role of the gastrointestinal tract in zinc excretion remains unclear. Zinc transporters are key regulators of zinc metabolism that mediate the movement of zinc ions across membranes. Here, we identified a comprehensive list of 14 predicted Cation Diffusion Facilitator (CDF) family zinc transporters in Caenorhabditis elegans and demonstrated that zinc is excreted from intestinal cells by one of these CDF proteins, TTM-1B. The ttm-1 locus encodes two transcripts, ttm-1a and ttm-1b, that use different transcription start sites. ttm-1b expression was induced by high levels of zinc specifically in intestinal cells, whereas ttm-1a was not induced by zinc. TTM-1B was localized to the apical plasma membrane of intestinal cells, and analyses of loss-of-function mutant animals indicated that TTM-1B promotes zinc excretion into the intestinal lumen. Zinc excretion mediated by TTM-1B contributes to zinc detoxification. These observations indicate that ttm-1 is a component of a negative feedback circuit, since high levels of cytoplasmic zinc increase ttm-1b transcript levels and TTM-1B protein functions to reduce the level of cytoplasmic zinc. We showed that TTM-1 isoforms function in tandem with CDF-2, which is also induced by high levels of cytoplasmic zinc and reduces cytoplasmic zinc levels by sequestering zinc in lysosome-related organelles. These findings define a parallel negative feedback circuit that promotes zinc homeostasis and advance the understanding of the physiological roles of the gastrointestinal tract in zinc metabolism in animals. PMID:23717214

Roh, Hyun Cheol; Collier, Sara; Deshmukh, Krupa; Guthrie, James; Robertson, J David; Kornfeld, Kerry

2013-05-23

412

A zinc-finger transcription factor induced by TGF-? promotes apoptotic cell death in epithelial Mv1Lu cells  

Microsoft Academic Search

Transforming growth factor-? (TGF-?) superfamily members constitute a group of multifunctional factors that are able to stimulate apoptotic cell death in a variety of cells. In this report, we show that a zinc-finger transcription factor (TIEG) is an immediate early gene transcriptionally induced by TGF-? in the epithelial Mv1Lu cell line. We also demonstrate that, mimicking TGF-? effects, ectopic overexpression

Elisabet Chalaux; Teresa López-Rovira; Jose Luis Rosa; Gabriel Pons; Linda M. Boxer; Ramon Bartrons; Francesc Ventura

1999-01-01

413

Material constraints for thin-film solar cells  

Microsoft Academic Search

Harnessing solar energy by using photovoltaic cells has the potential to become a major CO2-free energy source. Materials requirements for the solar cells based on four types of thin-film photovoltaics have been estimated and compared with global reserves, resources and annual refining. The use of solar cells based on Cd, Ga, Ge, In, Ru, Se and Te as a major

B. A Andersson; C Azar; J Holmberg; S Karlsson

1998-01-01

414

Determination of the solar cell panel installation angle  

Microsoft Academic Search

The output power of the solar cell panel is highly affected by the sunlight incident angle. The efficiency can be improved if the solar cell panel is properly installed with the optimum angle. The relationship between the sunlight incident angle and the sunlight radiation intensity on the solar cell panel surface is presented in this paper. Genetic algorithms with climatic

Yaow-Ming Chen; Hsu-Chin Wu

2001-01-01

415

Flexible thermal cycle test equipment for concentrator solar cells  

DOEpatents

A system and method for performing thermal stress testing of photovoltaic solar cells is presented. The system and method allows rapid testing of photovoltaic solar cells under controllable thermal conditions. The system and method presents a means of rapidly applying thermal stresses to one or more photovoltaic solar cells in a consistent and repeatable manner.

Hebert, Peter H. (Glendale, CA); Brandt, Randolph J. (Palmdale, CA)

2012-06-19

416

A Photoelectrochemical Solar Cell: An Undergraduate Experiment.  

ERIC Educational Resources Information Center

|Preparation and testing of a cadmium selenide photoelectrical solar cell was introduced into an environmental chemistry course to illustrate solid state semiconductor and electrochemical principles. Background information, procedures, and results are provided for the experiment which can be accomplished in a three- to four-hour laboratory session…

Boudreau, Sharon M.; And Others

1983-01-01

417

Photon degradation effects in terrestrial solar cells  

Microsoft Academic Search

A certain type of photon degradation effect has been observed experimentally in n(+)\\/p solar cells. It is found that this effect is caused by a recombination center, the formation of which requires the simultaneous presence of a lattice defect and a silver atom or complex of atoms. The center is electrically active in its equilibrium state; the energy level of

V. G. Weizer; H. W. Brandhorst; J. D. Broder; R. E. Hart; J. H. Lamneck

1978-01-01

418

Screen printed boron emitters for solar cells  

Microsoft Academic Search

Screen printed (SP) boron emitters are presented as a useful option for the manufacturing of p-type emitters of solar cells. Details are provided on the diffusion process, including deposition, drying and firing steps, the latter performed in an infrared belt furnace. Besides their main dependences on the firing conditions, the sheet resistances and dopant profiles of the resulting emitters reveal

F. Recart; I. Freire; L. Pérez; R. Lago-Aurrekoetxea; J. C. Jimeno; G. Bueno

2007-01-01

419

The fatigue properties of solar cell interconnectors  

Microsoft Academic Search

The fatigue properties of varieties of silver plated molybdenum and silver mesh solar cell interconnectors were determined by deflection controlled cyclic tests at low temperature using a specially designed test unit. While the test conditions did not exactly simulate those experienced in service, the results allow comparisons to be made based on the fatigue properties of existing interconnectors and conclusions

R. B. Evans; S. Stevens

1978-01-01

420

Fatigue properties of solar cell interconnectors  

Microsoft Academic Search

A test rig was developed to evaluate the fatigue properties of molybdenum and silver mesh solar cell interconnectors at temperatures of -130 C and -170 C. The rig consists of an electromagnetic vibrator and a specimen clamping system and is operated using a closed loop system of control. The molybdenum interconnectors contain a complex loop to provide flexibility. The effect

R. B. Evans; S. Stevens; P. Campbell

1977-01-01

421

Fatigue Properties of Solar Cell Interconnectors.  

National Technical Information Service (NTIS)

A test rig was developed to evaluate the fatigue properties of molybdenum and silver mesh solar cell interconnectors at temperatures of -130 C and -170 C. The rig consists of an electromagnetic vibrator and a specimen clamping system and is operated using...

R. B. Evans S. Stevens P. Campbell

1977-01-01

422

A Bicontinuous Double Gyroid Hybrid Solar Cell  

Microsoft Academic Search

We report the first successful application of an ordered bicontinuous gyroid semiconducting network in a hybrid bulk heterojunction solar cell. The freestanding gyroid network is fabricated by electrochemical deposition into the 10 nm wide voided channels of a self-assembled, selectively degradable block copolymer film. The highly ordered pore structure is ideal for uniform infiltration of an organic hole transporting material,

Edward J. W. Crossland; Marleen Kamperman; Mihaela Nedelcu; Caterina Ducati; Ulrich Wiesner; Detlef-M. Smilgies; Gilman E. S. Toombes; Marc A. Hillmyer; Sabine Ludwigs; Ullrich Steiner; Henry J. Snaith

2009-01-01

423

Integral screen printed solar cells panel  

Microsoft Academic Search

This paper summarizes our activities in the field of process technologies for the fabrication of photovoltaic devices. The study is strongly focused on the integral screen printing technique for the fabrication of single crystal solar cells, using standard equipments available in our laboratory. The challenging aim of this survey is to attain encouraging results with very modest means. Knowing that

Y. Boukennous; B. Benyahia; M. R. Charif; A. Elamrani; M. F. Moussa

424

Phthalocyanine Blends Improve Bulk Heterojunction Solar Cells  

PubMed Central

A core phthalocyanine platform allows engineering the solubility properties the band gap; shifting the maximum absorption toward the red. A simple method to increase the efficiency of heterojunction solar cells uses a self-organized blend of the phthalocyanine chromophores fabricated by solution processing.

Varotto, Alessandro; Nam, Chang-Yong; Radivojevic, Ivana; Tome, Joao; Cavaleiro, Jose A.S.; Black, Charles T.; Drain, Charles Michael

2010-01-01

425

Development of high efficiency solar cells  

Microsoft Academic Search

Emphasis was on developing new polycrystal growth techniques, developing new analytical techniques to study grain boundaries, and fundamental studies of the physical mechanisms by which grain boundaries limit solar cell performance. Molecular beam epitaxy proved to be a very attractive technique for fundamental studies of both grain boundaries and unique device structures. Several high spatial resolution analytical techniques were developed

D. L. Miller; M. J. Cohen; J. S. Harris Jr.; J. J. Loferski; J. Ballantyne; T. Bhar; E. Stefanakos

1979-01-01

426

Solar-Cell Testing and Evaluation.  

National Technical Information Service (NTIS)

A two year study of the degradation effects in AlGaAs/GaAs solar cells is described. Illuminated current-voltage measurements were made during temperature and humidity cycling and time dependent degradation measurements were recorded. (ERA citation 07:061...

E. K. Stefanakos W. J. Collis

1982-01-01

427

Screen printed interdigitated back contact solar cell  

NASA Astrophysics Data System (ADS)

Interdigitated back contact solar cells are made by screen printing dopant materials onto the back surface of a semiconductor substrate in a pair of interdigitated patterns. These dopant materials are then diffused into the substrate to form junctions having configurations corresponding to these patterns. Contacts having configurations which match the patterns are then applied over the junctions.

Baraona, C. R.; Mazaris, G. A.; Chai, A. T.

1984-10-01

428

Microscopy for Graetzel Solar cells manufacturing  

Microsoft Academic Search

The Graetzel solar cells are devices composed by two transparent glass conductive surfaces, one nanocrystalline structure interfase of TiO 2 , where a dye is introduced. The manufacturing process includes tasks where microscopy is an important tool. For instance an intermediate task is make conductive a SiO2 glass that normally is non conductive, so it is necessary take into account

Héctor I. Olmos Castillo; Gerardo Zavala Guzmán

429

Transparent conductors for solar cell applications  

SciTech Connect

Non-stoichiometric and doped films of oxides of Sn, In, Cd, Zn and their alloys are highly transparent in the visible and also electrically conducting. The preparation and electro-optical properties of these films, and their applications in solar cells are reviewed.

Chopra, K.L.; Major, S.

1983-05-01

430

Defect analysis in polycrystalline silicon solar cells  

SciTech Connect

Localized bulk defects like diffusion length variations and structural defects like grain boundaries are analyzed in polycrystalline silicon solar cells using laser scanning and deep level transient spectroscopy techniques. The effect of hydrogen passivation on the role of grain boundaries has been studied.

Sastry, O.S.; Dutta, V.; Mukerjee, A.K.; Chopra, K.L.

1985-06-15

431

Nanostructured Solar Cells for High Efficiency Photovoltaics  

Microsoft Academic Search

The use of nanostructures in photovoltaics offers the potential for high efficiency by either using new physical mechanisms or by allowing solar cells which have efficiencies closer to their theoretical maximum, for example by tailoring material properties. At the same time, nanostructures have potentially low fabrication costs, moving to structures or materials which can be fabricated using chemically or biologically

Christiana B. Honsberg; Allen M. Barnett; Douglas Kirkpatrick

2006-01-01

432

Improved Thin-Film Solar Cells.  

National Technical Information Service (NTIS)

During this contract thin-film GaAs solar cells using semitransparent Pt layers as the barrier contact have been made and investigated to improve their photovoltaic characteristics. Studies of the GaAs film, grown by the close-spaced oxide transport proce...

D. M. Perkins W. L. Hui G. Noel E. F. Pasierb

1966-01-01

433

Facilitation of granule cell epileptiform activity by mossy fiber-released zinc in the pilocarpine model of temporal lobe epilepsy  

Microsoft Academic Search

Recurrent mossy fiber synapses in the dentate gyrus of epileptic brain facilitate the synchronous firing of granule cells and may promote seizure propagation. Mossy fiber terminals contain and release zinc. Released zinc inhibits the activation of NMDA receptors and may therefore oppose the development of granule cell epileptiform activity. Hippocampal slices from rats that had experienced pilocarpine-induced status epilepticus and

Olga Timofeeva; J. Victor Nadler

2006-01-01

434

Direct-Write Contacts for Solar Cells  

SciTech Connect

We report on our project to develop inkjet printable contacts for solar cells. Ag, Cu, and Ni metallizations were inkjet printed with near vacuum deposition quality. Thick, highly conducting lines of Ag and Cu demonstrating good adhesion to glass, Si, and PCB have been printed at 100-200 C in air and N2, respectively. Ag grids were inkjet-printed on Si solar cells and fired through silicon nitride AR layer at 850 C resulting in 8% cells. Next-generation multicomponent inks (including etching agents) have also been developed with improved fire-through contacts leading to higher cell efficiencies. The approach developed can be easily extended to other conductors such as Pt, Pd, and Au, etc. In addition, PEDOT-PSS polymer-based conductors were inkjet-printed with the conductivity as good or better than those of polymer-based conductors.

Kaydanova, T.; van Hest, M.F.A.M.; Miedaner, A.; Curtis, C. J.; Alleman, J. L.; Dabney, M. S.; Garnett, E.; Shaheen, S.; Ginley, D. S.; Smith, L.; Collins, R.; Hanoka, J. I.; Gabor, A. M.

2005-01-01

435

Extracellular zinc and zinc-citrate, acting through a putative zinc-sensing receptor, regulate growth and survival of prostate cancer cells.  

PubMed

Prostate Zn(2+) concentrations are among the highest in the body, and a marked decrease in the level of this ion is observed in prostate cancer. Extracellular Zn(2+) is known to regulate cell survival and proliferation in numerous tissues. In spite of this, a signaling role for extracellular Zn(2+) in prostate cancer has not been established. In the present study, we demonstrate that prostate metastatic cells are impermeable to Zn(2+), but extracellular Zn(2+) triggers a metabotropic Ca(2+) rise that is also apparent in the presence of citrate. Employing fluorescent imaging, we measured this activity in androgen-insensitive metastatic human cell lines, PC-3 and DU-145, and in mouse prostate tumor TRAMP-1 cells but not in androgen-sensitive LNCaP cells. The Ca(2+) response was inhibited by Galphaq and phospholipase C (PLC) inhibitors as well as by intracellular Ca(2+) store depletion, indicating that it is mediated by a Gq-coupled receptor that activates the inositol phosphate (IP(3)) pathway consistent with the previously identified zinc-sensing receptor (ZnR). Zn(2+)-dependent extracellular signal-regulated kinase and AKT activation, as well as enhanced Zn(2+)-dependent cell growth and survival, were observed in PC-3 cells that exhibit ZnR activity, but not in a ZnR activity-deficient PC-3 subline. Interestingly, application of Zn(2+)-citrate (Zn(2+)Cit), at physiological concentrations, was followed by a profound functional desensitization of extracellular Zn(2+)-dependent signaling and attenuation of Zn(2+)-dependent cell growth. Our results indicate that extracellular Zn(2+) and Zn(2+)Cit, by triggering or desensitizing ZnR activity, distinctly regulate prostate cancer cell growth. Thus, therapeutic strategies based either on Zn(2+) chelation or administration of Zn(2+)Cit may be effective in attenuating prostate tumor growth. PMID:18310092

Dubi, Noga; Gheber, Larisa; Fishman, Daniel; Sekler, Israel; Hershfinkel, Michal

2008-02-28

436

Soft tissue reactions evoked by implanted gallium phosphide.  

PubMed

Neural devices may play an important role in the diagnosis and therapy of several clinical conditions, such as stroke, trauma or neurodegenerative disorders, by facilitating motor and pain control. Such interfaces, chronically implanted in the CNS, need to be biocompatible and have the ability to stimulate and record nerve signals. However, neural devices of today are not fully optimized. Nanostructured surfaces may improve electrical properties and lower evoked tissue responses. Vertical gallium phosphide (GaP) nanowires epitaxially grown from a GaP surface is one way of creating nanostructured electrodes. Thus, we chose to study the soft tissue reactions evoked by GaP surfaces. GaP and the control material titanium (Ti) were implanted in the rat abdominal wall for evaluation of tissue reactions after 1, 6, or 12 weeks. The foreign-body response was evaluated by measuring the reactive capsule thickness and by quantification of ED1-positive macrophages and total cells in the capsule. Furthermore, the concentration of Ga was measured in blood, brain, liver and kidneys. Statistically significant differences were noticed between GaP and Ti at 12 weeks for total and ED1-positive cell densities in the capsule. The chemical analysis showed that the concentration of Ga in brain, liver and kidneys increased during 12 weeks of implantation, indicating loss of Ga from the implant. Taken together, our results show that the biocompatible properties of GaP are worse than those of the well-documented biomaterial Ti. PMID:18801568

Linsmeier, Cecilia E; Wallman, Lars; Faxius, Linda; Schouenborg, Jens; Bjursten, Lars M; Danielsen, Nils

2008-09-17

437

Microwave\\/Infrared-Laser Processing of Material for Solar Energy  

Microsoft Academic Search

\\u000a Several approaches have been studied for microwave material processing for solar energy utilization such as upgrading the\\u000a photocatalytic activity of TiO2, and improvement of efficiency in polymer solar cell. Recently, we observed the emission of zinc and oxygen plasmas from\\u000a ZnO ceramics during intense absorption of microwaves as well as the deposition of zinc and zinc oxide films. This finding

Taro Sonobe; Kyohei Yoshida; Kan Hachiya; Toshiteru Kii; Hideaki Ohgaki

438

Enhancing Solar Cell Efficiencies through 1-D Nanostructures  

NASA Astrophysics Data System (ADS)

The current global energy problem can be attributed to insufficient fossil fuel supplies and excessive greenhouse gas emissions resulting from increasing fossil fuel consumption. The huge demand for clean energy potentially can be met by solar-to-electricity conversions. The large-scale use of solar energy is not occurring due to the high cost and inadequate efficiencies of existing solar cells. Nanostructured materials have offered new opportunities to design more efficient solar cells, particularly one-dimensional (1-D) nanomaterials for enhancing solar cell efficiencies. These 1-D nanostructures, including nanotubes, nanowires, and nanorods, offer significant opportunities to improve efficiencies of solar cells by facilitating photon absorption, electron transport, and electron collection; however, tremendous challenges must be conquered before the large-scale commercialization of such cells. This review specifically focuses on the use of 1-D nanostructures for enhancing solar cell efficiencies. Other nanostructured solar cells or solar cells based on bulk materials are not covered in this review. Major topics addressed include dye-sensitized solar cells, quantum-dot-sensitized solar cells, and p-n junction solar cells.

Yu, Kehan; Chen, Junhong

2009-01-01

439

Donor-acceptor heterojunction solar cells based on perylene dimide and perylene bisbenzimidazole  

NASA Astrophysics Data System (ADS)

We have fabricated heterojunction solar cells comprising active layers of perylene diimide (PDI) or perylene bisbenzimidazole (CONPER, conjugated perylene dye) as electron acceptor and ZnPC as donor. Bilayer solar cells were produced by successive evaporation of zinc phthalocyanine (ZnPC) and perylene diimide (PDI) or perylene bisbenzimidazole (CONPER) on glass substrates coated with indium doped tin oxide. Active layers with different thickness were evaporated. The bilayer cells were characterized under simulated AM 1.5 illumination (100 mW/cm2). The best results were obtained for the device structure of ITO/PEDOT/ZnPC (40 nm)/perylene bisbenzimidazole (60 nm)/Al (70 nm). This paper has been presented at “ECHOS06”, Paris, 28 30 juin 2006.

Erten, S.; Meghdadi, F.; Gunes, S.; Koeppe, R.; Sariciftci, N. S.; Icli, S.

2006-12-01

440

Effects of zinc on programmed cell death of Musca domestica and Drosophila melanogaster blood cells.  

PubMed

Programmed cell death (PCD) and phagocytotic activity of immune cells play a pivotal role in insect development. We examined the influence of Zn(2+), an important element to fundamental biological processes, on phagocytosis and apoptosis of hemocytes in two fly species: Musca domestica and Drosophila melanogaster. Hemocytes were isolated from the third instar larvae of both species and treated for 3h with zinc chloride solutions, containing 0.35 mM or 1.7 mM of Zn(2+), and untreated as control. Phagocytotic activity of hemocytes was examined by flow cytometry after adding latex fluorescent beads to the medium, while apoptosis was evaluated by application of annexinV-FITC and pan-caspase-FITC inhibitor. Mitochondrial viability was determined by measuring resazurin absorbancy in the cell medium. The obtained results showed that Zn(2+) increases phagocytosis and affects PCD of both species hemocytes but each in a different way. Zinc decreases fraction of annexin-positive hemocytes in M. domestica but increases it in D. melanogaster. The pan-caspase analysis revealed low and high activity of caspases in hemocytes of M. domestica and D. melanogaster, respectively. Zn(2+) also decreased the viability of hemocyte mitochondria but only in D. melanogaster. It suggests that flies use different pathways of PCD, or that Zn plays a different role in this process in M. domestica than in D. melanogaster. PMID:19941868

Filipiak, Marta; Bilska, Ewelina; Tylko, Grzegorz; Pyza, Elzbieta

2009-12-02

441

High efficiency silicon MINP solar cells  

NASA Astrophysics Data System (ADS)

Investigations of high-efficiency MINP silicon solar cells are discussed. Emphasis is placed on cell characterization to develop a basic understanding of current-transport mechanisms which limit cell efficiency. Fabrication and characterization of cells based on 0.2 ohm-cm substrates, diffused emitters 150-200-nm deep, and with Mg MIS collector grids are discussed. A total-area AM1 efficiency of 16.8 percent has been achieved. Detailed analyses of photocurrent and current-loss mechanisms are presented and utilized to predict future directions of research.

Olsen, L. C.; Addis, F. W.; Miller, W. A.; Dunham, G.

442

Reverse bias degradation in dye solar cells  

NASA Astrophysics Data System (ADS)

A prolonged reverse bias (RB) stress forcing a short-circuit current through a dye solar cell, corresponding to the harshest test a shadowed cell may experience in real conditions, can cause the RB operating voltage VRB to drift with time, initially slowly but accelerating for VRB < (-1.65 +/- 0.15)V when gas bubbles, identified as H2 (gas chromatography), are produced inside the cell, leading to breakdown. A close connection between VRB, cell performance, and stability was established. Contributions to RB degradation include triiodide depletion and impurities, in particular water. Acting upon these components and setting up protection strategies is important for delivering long-lasting modules.

Mastroianni, Simone; Lanuti, Alessandro; Brown, Thomas M.; Argazzi, Roberto; Caramori, Stefano; Reale, Andrea; Di Carlo, Aldo

2012-09-01

443

Experimental study of variations of the solar spectrum of relevance to thin film solar cells  

Microsoft Academic Search

The influence of variations in the incident solar spectrum on solar cells is often neglected. This paper investigates the magnitude of this variation and its potential influence on the performance of thin film solar cells in a maritime climate. The investigation centres on the analysis of a large number of measurements carried out in Loughborough, UK, at 10min intervals over

R. Gottschalg; D. G. Infield; M. J. Kearney

2003-01-01

444

Electrodeposition of nanoporous ZnO on Al-doped ZnO leading to a highly organized structure for integration in Dye Sensitized Solar Cells  

Microsoft Academic Search

In the present study, we propose an improvement of the anode configuration in Zinc Oxide based Dye Sensitized Solar Cells (DSSC). Instead of the classical configuration, which is composed by two different metal oxides: one transparent conducting oxide (TCO) for the substrate and one nanostructured metal oxide for supporting the dye, the new approach is to use ZnO as unique

S. Haller; J. Rousset; G. Renou; D. Lincot

2011-01-01

445

Modeling the Effects of Solar Cell Distribution on Optical Cross Section for Solar Panel Simulation.  

National Technical Information Service (NTIS)

The Air Force Research Laboratory (AFRL) Time-domain Analysis Simulation for Advanced Tracking (TASAT) was used to explore the variation of Optical Cross Section (OCS) with glint angle for a solar panel with different solar cell distribution statistics. S...

K. Feirstine L. Vaughn M. Duggin M. Klein

2012-01-01

446

Role of zinc in cellular zinc trafficking and mineralization in a murine osteoblast-like cell line.  

PubMed

Zinc (Zn) supplementation stimulates bone growth in Zn-deficient humans and animals. A biphasic pattern of mineralization has been observed in cultured osteoblasts; an initiation phase and a progression phase. We used MC3T3-E1, a murine osteoblastic cell line, to elucidate the physiological role of Zn in osteoblast mineralization and cellular Zn trafficking during the mineralization event. Cells were cultured in media containing Chelex-treated fetal bovine serum and 1, 4, 10 and 20 ?M Zn as ZnSO(4) for 14 days (early phase of mineralization) or 21 days (mid-to-late phase of mineralization). During the early phase of mineralization, Alizarin Red staining indicated that mineralization was increased by Zn in a dose-dependent manner. Although Zn exposure did not affect monolayer Zn concentration, metallothionein (MT) mRNA expression increased dose-dependently as assessed by real-time PCR. During the late phase of mineralization, mineralization was maximal at 1 ?M Zn and monolayer Zn concentration reflected Zn exposure. The increase in MT mRNA expression during the late phase was similar to that during the early phase, but the difference in expression between culture Zn concentrations tended to be smaller. ZnT-2 mRNA expression decreased significantly with increasing zinc concentrations in the culture medium during the early phase, but increased significantly during the late phase. Osteocalcin mRNA levels were positively correlated to Zn exposure at both time points. Taken together, we propose that Zn may play an important role in osteoblast mineralization through Zn trafficking involving Zn storage proteins and Zn transporters. PMID:20378322

Nagata, Masashi; Lönnerdal, Bo

2010-04-08

447

18 percent efficient polycrystalline silicon solar cells  

NASA Astrophysics Data System (ADS)

Over the past 7 yr, there has been marked improvements in crystalline silicon solar cell performance, with the highest independently confirmed cell efficiency increasing from 17.1 percent to 24.2 percent. Work directed at transferring some of these improvements to polycrystalline silicon cells is described. Applying a high-efficiency crystalline cell sequence has given efficiencies as high as 17.8 percent with the addition of a phosphorous pretreatment step and modifications of a rear Al alloying step and cell processing temperatures. Surface texturing is identified as an important area requiring attention to obtain the highest possible efficiency. Laser texturing has given the best results to date for polycrystalline substrates. Results are described for a laser-textured, laser-grooved cell processing sequence with the potential to produce polycrystalline cells having efficiencies well above 18 percent.

Narayanan, S.; Zolper, J.; Yun, F.; Wenham, S. R.; Sproul, A. B.

448

One-dimensional (1D) ZnO nanowires dye sensitized solar cell.  

PubMed

High ordered one-dimensional (1D) Zinc oxide (ZnO) nanowires were grown on FTO substrate by using the hydrothermal method. Nanowires structures were used as the wide band-gap semiconducting photo-electrode in dye sensitized solar cell (DSSCs). Solar cell made from ZnO nanowire at 50 nm radius and several tens micron lengths showed high solar conversion efficiency (eta) of 2.1% and incident photon current efficiency (IPCE) 35% using nanowire/N719 dye/I-/I3- electrolyte. We also compared Ru N719 dye and N3 dye on ZnO nanowire against each other in respect to solar conversion efficiency and IPCE measurements. In the case of the N3 dye on ZnO nanowire conversion efficiency (eta) of 1.32% and IPCE 23% were obtained under an illumination of 100 mW/cm2. It was found that the performance of the Ru N719 dyes was better than about 50% that of the N3 dye in ZnO nanowire dye-sensitized solar cells. PMID:23646734

Kiliç, Bayram; Wang, Lianzhou; Ozdemir, Orhan; Lu, Max; Tüzemen, Sebahattin

2013-01-01

449

Galvanostatic non-destructive characterization of alkaline silver–zinc cells  

Microsoft Academic Search

Alkaline silver–zinc cells of different capacity have been characterised by a galvanostatic non-destructive technique (GNDT). Cells with capacities between 10.6 and 58.5Ah exhibit lower internal resistance than those with capacities between 1.7 and 5.8Ah. From analysis of voltage–time transient data, it is concluded that only the cells with capacities between 10.6 and 58.5Ah can sustain high-drain applications.

B. Hariprakash; S. K. Martha; A. K. Shukla

2003-01-01

450

Surface textured ZnO:Al films by RF magnetron sputtering deposition for thin film solar cells  

Microsoft Academic Search

Summary form only given. Transparent conductive oxide (TCO) is indispensable as the front electrode for most thin film solar cells. Aluminum-doped zinc oxide films (ZnO:Al) were prepared by RF magnetron sputtering on glass (Corning 1737) substrates as a function of the deposition condition. This system has three targets to enable simultaneous sputtering. One of them was a 4 inch disk

J. S. Yoo; J. C. Lee; S. K. Kim; K. H. Yoon; I. J. Park; D. Y. Kim; Junsin Yi

2004-01-01

451

Electrochemistry of the Zinc-Silver Oxide System. Part 2: Practical Measurements of Energy Conversion Using Commercial Miniature Cells.  

ERIC Educational Resources Information Center

Summarizes the quantitative relationships pertaining to the operation of electrochemical cells. Energy conversion efficiency, cycle efficiency, battery power, and energy/power density of two types of zinc-silver oxide cells are discussed. (YP)

Smith, Michael J.; Vincent, Colin A.

1989-01-01

452

Electrochemistry of the Zinc-Silver Oxide System. Part 2: Practical Measurements of Energy Conversion Using Commercial Miniature Cells.  

ERIC Educational Resources Information Center

|Summarizes the quantitative relationships pertaining to the operation of electrochemical cells. Energy conversion efficiency, cycle efficiency, battery power, and energy/power density of two types of zinc-silver oxide cells are discussed. (YP)|

Smith, Michael J.; Vincent, Colin A.

1989-01-01

453

The effect of cell design and storage conditions on the cycle life performance silver-zinc cells  

Microsoft Academic Search

The Mars Pathfinder spacecraft is expected to utilize a single eighteen cell, forty ampere-hour, silver-zinc battery. The calendar life clock for the battery begins with the addition of KOH electrolyte to the constituent cells by the vendor. A period of battery inactivity begins with shipment of the battery to JPL and then on to Florida. This inactivity continues while the

D. E. Perrone; M. Klekotka; S. Di Stefano

1996-01-01

454

miR-183-96-182 Cluster Is Overexpressed in Prostate Tissue and Regulates Zinc Homeostasis in Prostate Cells*  

PubMed Central

Decreased zinc levels are a hallmark of prostate cancer tumors as zinc uniquely concentrates in healthy prostate tissue. Increased dietary zinc correlates with decreased risk of advanced prostate cancer and decreased mortality from prostate cancer. The mechanisms of prostatic zinc homeostasis are not known. Lower zinc levels in the tumor are correlated directly with decreased expression of the zinc transporter hZIP1. We report identification of a microRNA cluster that regulates multiple zinc transporters, including hZIP1. Screening in laser capture microdissected prostate cancer tumors identified miR-182 as a potential regulator of hZIP1. Regulation of hZIP1 by miR-182 via two binding sites was confirmed in primary prostate cell cultures. miR-96 and miR-183 are expressed as a cluster with miR-182 and share similar sequences. Array profiling of tissue showed that miR-183, -96, and -182 are higher in prostate cancer tissue compared with normal prostate. Overexpression of the entire miR-183-96-182 cluster suppressed five additional zinc transporters. Overexpression of miR-183, -96, and -182 individually or as a cluster diminished labile zinc pools and reduced zinc uptake, demonstrating this miR cluster as a regulator of zinc homeostasis. We observed regulation of zinc homeostasis by this cluster in prostate cells and HEK-293 cells, suggesting a universal mechanism that is not prostate-specific. To our knowledge, this is the first report of a miR cluster targeting a family of metal transport proteins. Individually or as a cluster, miR-183, -96, and -182 are overexpressed in other cancers too, implicating this miR cluster in carcinogenesis.

Mihelich, Brittany L.; Khramtsova, Ekaterina A.; Arva, Nicole; Vaishnav, Avani; Johnson, Daniel N.; Giangreco, Angeline A.; Martens-Uzunova, Elena; Bagasra, Omar; Kajdacsy-Balla, Andre; Nonn, Larisa

2011-01-01

455

Role of thin n-type metal-oxide interlayers in inverted organic solar cells.  

PubMed

We have investigated the photovoltaic properties of inverted solar cells comprising a bulk heterojunction film of poly(3-hexylthiophene) and phenyl-C(61)-butyric acid methyl ester, sandwiched between an indium-tin-oxide/Al-doped zinc oxide (ZnO-Al) front, and tungsten oxide/aluminum back electrodes. The inverted solar cells convert photons to electrons at an external quantum efficiency (EQE) exceeding 70%. This is a 10-15% increase over EQEs of conventional solar cells. The increase in EQE is not fully explained by the difference in the optical transparency of electrodes, interference effects due to an optical spacer effect of the metal-oxide electrode buffer layers, or variation in charge generation profile. We propose that a large additional splitting of excited states at the ZnO-Al/polymer interface leads to the considerably large photocurrent yield in inverted cells. Our finding provides new insights into the benefits of n-type metal-oxide interlayers in bulk heterojunction solar cells, namely the splitting of excited states and conduction of free electrons simultaneously. PMID:22834558

Gadisa, Abay; Liu, Yingchi; Samulski, Edward T; Lopez, Rene

2012-07-26

456

Development of silver-zinc cells of improved cycle life and energy density. Final report  

Microsoft Academic Search

This document describes a Small Business Innovative Research (SBIR) Phase II program. The research was designed to improve the cycle life and energy density of silver zinc cells, particularly those used in naval propulsion systems, by advancing the state of the art of the negative electrode and the separator, which are responsible for most of the shortcomings of this electrochemical

Serenyi

1996-01-01

457

Evaluation of liquid-gas separator materials for a silver zinc cell vent  

Microsoft Academic Search

The gas permeability of TFE Teflon, FEP Teflon, polyethylene, and microporous Teflon was measured in order to evaluate the suitability of these materials for use as liquid-gas separators for silver zinc cell vents. Microporous Teflon was found to have ideal characteristics for a liquid-gas separator. This material has a high gas permeability, it is not wetted by electrolyte, and it

C. C. Badcock; A. H. Zimmerman

1979-01-01

458

Evaluation of Liquid-Gas Separator Materials for a Silver Zinc Cell Vent.  

National Technical Information Service (NTIS)

The gas permeability of TFE Teflon, FEP Teflon, polyethylene, and microporous Teflon was measured in order to evaluate the suitability of these materials for use as liquid-gas separators for silver zinc cell vents. Microporous Teflon was found to have ide...

A. H. Zimmerman C. C. Badcock

1979-01-01

459

Solar cell single measurement maximum power point tracking  

Microsoft Academic Search

It is possible to give a valuable estimation for an entire solar array IV curve, based only on a single working point (current and voltage) measurement, on panels of solar cells, when several of their parameters are known and environmental parameters also known. The estimations were performed using Matlab\\/Simulink and the simulation is based on the 10 parameter solar cell

Raul Rabinovici; Yotam B. Frechter

2010-01-01

460

High performance organic solar cells with interface engineering  

Microsoft Academic Search

Polymer solar cells are considered a promising candidate for renewable energy with low-cost and high volume production capability. The main focus of this dissertation is to investigate the several approaches for improving the efficiency of polymer solar cells. These approaches include understanding of the physics, operation mechanisms, materials and device engineering and optimization of fabrication processes. A typical polymer solar

Mi Hyae Park

2010-01-01

461

Recent advances in sensitized mesoscopic solar cells.  

PubMed

Perhaps the largest challenge for our global society is to find ways to replace the slowly but inevitably vanishing fossil fuel supplies by renewable resources and, at the same time, avoid negative effects from the current energy system on climate, environment, and health. The quality of human life to a large degree depends upon the availability of clean energy sources. The worldwide power consumption is expected to double in the next 3 decades because of the increase in world population and the rising demand of energy in the developing countries. This implies enhanced depletion of fossil fuel reserves, leading to further aggravation of the environmental pollution. As a consequence of dwindling resources, a huge power supply gap of 14 terawatts is expected to open up by year 2050 equaling today's entire consumption, thus threatening to create a planetary emergency of gigantic dimensions. Solar energy is expected to play a crucial role as a future energy source. The sun provides about 120,000 terawatts to the earth's surface, which amounts to 6000 times the present rate of the world's energy consumption. However, capturing solar energy and converting it to electricity or chemical fuels, such as hydrogen, at low cost and using abundantly available raw materials remains a huge challenge. Chemistry is expected to make pivotal contributions to identify environmentally friendly solutions to this energy problem. One area of great promise is that of solar converters generally referred to as "organic photovoltaic cells" (OPV) that employ organic constituents for light harvesting or charge carrier transport. While this field is still in its infancy, it is receiving enormous research attention, with the number of publications growing exponentially over the past decade. The advantage of this new generation of solar cells is that they can be produced at low cost, i.e., potentially less than 1 U.S. $/peak watt. Some but not all OPV embodiments can avoid the expensive and energy-intensive high vacuum and materials purification steps that are currently employed in the fabrication of all other thin-film solar cells. Organic materials are abundantly available, so that the technology can be scaled up to the terawatt scale without running into feedstock supply problems. This gives organic-based solar cells an advantage over the two major competing thin-film photovoltaic devices, i.e., CdTe and CuIn(As)Se, which use highly toxic materials of low natural abundance. However, a drawback of t