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Sample records for nanostructured dye solar

  1. nanostructures for dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Rashad, M. M.; Shalan, A. E.

    2014-08-01

    Hierarchical architectures consisting of one-dimensional (1D) nanostructures are of great interest for potential use in energy and environmental applications in recent years. In this work, hierarchical tungsten oxide (WO3) has been synthesized via a facile hydrothermal route from ammonium metatungstate hydrate and implemented as photoelectrode for dye-sensitized solar cells. The urchin-like WO3 micro-patterns are constructed by self-organized nanoscale length 1D building blocks, which are single crystalline in nature, grown along (001) direction and confirm an orthorhombic crystal phase. The obtained powders were investigated by XRD, SEM, TEM and UV-Vis Spectroscopy. The photovoltaic performance of dye-sensitized solar cells based on WO3 photoanodes was investigated. With increasing the calcination temperature of the prepared nanopowders, the light-electricity conversion efficiency ( η) was increased. The results were attributed to increase the crystallinity of the particles and ease of electron movement. The DSSC based on hierarchical WO3 showed a short-circuit current, an open-circuit voltage, a fill factor, and a conversion efficiency of 4.241 mA/cm2, 0.656 V, 66.74, and 1.85 %, respectively.

  2. Monitoring the dye impregnation time of nanostructured photoanodes for dye sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Shahzad, N.; Pugliese, D.; Lamberti, A.; Sacco, A.; Virga, A.; Gazia, R.; Bianco, S.; Shahzad, M. I.; Tresso, E.; Pirri, C. F.

    2013-06-01

    Dye-sensitized solar cells (DSSCs) are getting increasing attention as low-cost, easy-to-prepare and colored photovoltaic devices. In the current work, in view of optimizing the fabrication procedures and understanding the mechanisms of dye attachment to the semiconductor photoanode, absorbance measurements have been performed at different dye impregnation times ranging from few minutes to 24 hours using UV-Vis spectroscopy. In addition to the traditional absorbance experiments, based on diffuse and specular reflectance on dye impregnated thin films and on the desorption of dye molecules from the photoanodes by means of a basic solution, an alternative in-situ solution depletion measurement, which enables fast and continuous evaluation of dye uptake, is presented. Photoanodes have been prepared with two different nanostructured semiconducting films: mesoporous TiO2, using a commercially available paste from Solaronix, and sponge-like ZnO obtained in our laboratory from sputtering and thermal annealing. Two different dyes have been analyzed: Ruthenizer 535-bisTBA (N719), which is widely used because it gives optimal photovoltaic performances, and a new metal-free organic dye based on a hemisquaraine molecule (CT1). Dye sensitized cells were fabricated using a customized microfluidic architecture. The results of absorbance measurements are presented and discussed in relation to the obtained solar energy conversion efficiencies and the incident photon-to-electron conversion efficiencies (IPCE).

  3. Progress in nanostructured photoanodes for dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Liu, Xueyang; Fang, Jian; Liu, Yong; Lin, Tong

    2016-05-01

    Solar cells represent a principal energy technology to convert light into electricity. Commercial solar cells are at present predominately produced by single- or multi-crystalline silicon wafers. The main drawback to silicon-based solar cells, however, is high material and manufacturing costs. Dye-sensitized solar cells (DSSCs) have attracted much attention during recent years because of the low production cost and other advantages. The photoanode (working electrode) plays a key role in determining the performance of DSSCs. In particular, nanostructured photoanodes with a large surface area, high electron transfer efficiency, and low electron recombination facilitate to prepare DSSCs with high energy conversion efficiency. In this review article, we summarize recent progress in the development of novel photoanodes for DSSCs. Effect of semiconductor material (e.g. TiO2, ZnO, SnO2, N2O5, and nano carbon), preparation, morphology and structure (e.g. nanoparticles, nanorods, nanofibers, nanotubes, fiber/particle composites, and hierarchical structure) on photovoltaic performance of DSSCs is described. The possibility of replacing silicon-based solar cells with DSSCs is discussed.

  4. Progress in nanostructured photoanodes for dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Liu, Xueyang; Fang, Jian; Liu, Yong; Lin, Tong

    2016-09-01

    Solar cells represent a principal energy technology to convert light into electricity. Commercial solar cells are at present predominately produced by single- or multi-crystalline silicon wafers. The main drawback to silicon-based solar cells, however, is high material and manufacturing costs. Dye-sensitized solar cells (DSSCs) have attracted much attention during recent years because of the low production cost and other advantages. The photoanode (working electrode) plays a key role in determining the performance of DSSCs. In particular, nanostructured photoanodes with a large surface area, high electron transfer efficiency, and low electron recombination facilitate to prepare DSSCs with high energy conversion efficiency. In this review article, we summarize recent progress in the development of novel photoanodes for DSSCs. Effect of semiconductor material (e.g. TiO2, ZnO, SnO2, N2O5, and nano carbon), preparation, morphology and structure (e.g. nanoparticles, nanorods, nanofibers, nanotubes, fiber/particle composites, and hierarchical structure) on photovoltaic performance of DSSCs is described. The possibility of replacing silicon-based solar cells with DSSCs is discussed.

  5. Characteristics of nanostructure dye-sensitized solar cells using food dyes

    NASA Astrophysics Data System (ADS)

    Hosseinnezhad, M.; Rouhani, S.

    2016-01-01

    Dye-sensitized solar cells (DSSCs) were prepared using various food dyes. Food dyes are economically superior to organometallic dyes since they are nontoxic and inexpensive. The spectrophotometric evaluation of chosen food dyes in solution and on a TO2 substrate show that the dyes form J-aggregation on the photoelectrode substrate. Oxidation of potential measurements for used food dyes ensured an energetically permissible and thermodynamically favorable charge transfer throughout the continuous cycle of a photo-electric conversion. The performance of dye-sensitized solar cells based on food dyes was studied. The results illustrate that the dye containing carboxylic acid and sulfonic acid as the acceptor group gave the maximum conversion efficiency 4.20%.

  6. Characteristics of nanostructure dye-sensitized solar cells using food dyes

    NASA Astrophysics Data System (ADS)

    Hosseinnezhad, M.; Rouhani, S.

    2016-01-01

    Dye-sensitized solar cells (DSSCs) were prepared using various food dyes. Food dyes are economically superior to organometallic dyes since they are nontoxic and inexpensive. The spectrophotometric evaluation of chosen food dyes in solution and on a TiO2 substrate show that the dyes form J-aggregation on the photoelectrode substrate. Oxidation of potential measurements for used food dyes ensured an energetically permissible and thermodynamically favorable charge transfer throughout the continuous cycle of a photo-electric conversion. The performance of dye-sensitized solar cells based on food dyes was studied. The results illustrate that the dye containing carboxylic acid and sulfonic acid as the acceptor group gave the maximum conversion efficiency 4.20%.

  7. TiO2 hierarchical nanostructures: Hydrothermal fabrication and application in dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Liang, Jia; Zhang, Gengmin; Yang, Jin; Sun, Wentao; Shi, Mingji

    2015-01-01

    Arrays of TiO2 hierarchical nanostructures that consisted of rutile nanorods and anatase branches were hydrothermally fabricated and employed as photoanodes in dye-sensitized solar cells (DSSCs). Each hierarchical nanostructure array was attained in two steps. First, a primary nanorod array was synthesized in aqueous solutions of hydrochloric acid (HCl) and tetrabutyl titanate (C16H36O4Ti); subsequently, secondary branches were grown on the nanorods in aqueous solutions of ammonium hexafluorotitanate ((NH4)2TiF6) and boric acid (H3BO3). The secondary anatase branches filled part of the space among the primary rutile nanorods and gave rise to a larger surface area. Light-harvesting capability of the DSSCs with TiO2 hierarchical nanostructures as photoanodes was appreciably improved because more dye molecules could be loaded on the photoanodes and more light could be scattered inside the DSSCs. Therefore, the conversion efficiencies of the DSSCs were doubled by replacing the photoanode of primary TiO2 nanorod array with the photoanodes of TiO2 hierarchical nanostructure arrays. Furthermore, in order to reach a compromise between the photoanode surface area and the inter-nanorod space volume, the growth time of the secondary TiO2 anatase branches was optimized.

  8. Interaction of Sensitizing Dyes with Nanostructured TiO2 Film in Dye-Sensitized Solar Cells Using Terahertz Spectroscopy.

    PubMed

    Ghann, William; Rahman, Aunik; Rahman, Anis; Uddin, Jamal

    2016-01-01

    The objective of this investigation was to shed light on the nature of interaction of different organic dyes and an inorganic dye, Ruthenium (II) polypyridine complex, with TiO2 nanoparticles. TiO2 is commonly deployed as an efficient energy transfer electrode in dye sensitized solar cells. The efficiency of dye sensitized solar cells is a function of the interaction of a dye with the electrode material such as TiO2. To the best of our knowledge the present study is the first effort in the determination of terahertz absorbance signals, investigation of real-time dye permeation kinetics, and the surface profiling and 3D imaging of dye sensitized TiO2 films. Herein, we report that the terahertz spectra of the natural dye sensitized TiO2 films were distinctively different from that of the inorganic dye with prominent absorption of natural dyes occurring at approximately the same wavelength. It was observed that the permeation of the natural dyes were more uniform through the layers of the mesoporous TiO2 compared to the inorganic dye. Finally, defects and flaws on TiO2 film were easily recognized via surface profiling and 3D imaging of the films. The findings thus offer a new approach in characterization of dye sensitized solar cells. PMID:27443236

  9. Interaction of Sensitizing Dyes with Nanostructured TiO2 Film in Dye-Sensitized Solar Cells Using Terahertz Spectroscopy

    PubMed Central

    Ghann, William; Rahman, Aunik; Rahman, Anis; Uddin, Jamal

    2016-01-01

    The objective of this investigation was to shed light on the nature of interaction of different organic dyes and an inorganic dye, Ruthenium (II) polypyridine complex, with TiO2 nanoparticles. TiO2 is commonly deployed as an efficient energy transfer electrode in dye sensitized solar cells. The efficiency of dye sensitized solar cells is a function of the interaction of a dye with the electrode material such as TiO2. To the best of our knowledge the present study is the first effort in the determination of terahertz absorbance signals, investigation of real-time dye permeation kinetics, and the surface profiling and 3D imaging of dye sensitized TiO2 films. Herein, we report that the terahertz spectra of the natural dye sensitized TiO2 films were distinctively different from that of the inorganic dye with prominent absorption of natural dyes occurring at approximately the same wavelength. It was observed that the permeation of the natural dyes were more uniform through the layers of the mesoporous TiO2 compared to the inorganic dye. Finally, defects and flaws on TiO2 film were easily recognized via surface profiling and 3D imaging of the films. The findings thus offer a new approach in characterization of dye sensitized solar cells. PMID:27443236

  10. Interaction of Sensitizing Dyes with Nanostructured TiO2 Film in Dye-Sensitized Solar Cells Using Terahertz Spectroscopy

    NASA Astrophysics Data System (ADS)

    Ghann, William; Rahman, Aunik; Rahman, Anis; Uddin, Jamal

    2016-07-01

    The objective of this investigation was to shed light on the nature of interaction of different organic dyes and an inorganic dye, Ruthenium (II) polypyridine complex, with TiO2 nanoparticles. TiO2 is commonly deployed as an efficient energy transfer electrode in dye sensitized solar cells. The efficiency of dye sensitized solar cells is a function of the interaction of a dye with the electrode material such as TiO2. To the best of our knowledge the present study is the first effort in the determination of terahertz absorbance signals, investigation of real-time dye permeation kinetics, and the surface profiling and 3D imaging of dye sensitized TiO2 films. Herein, we report that the terahertz spectra of the natural dye sensitized TiO2 films were distinctively different from that of the inorganic dye with prominent absorption of natural dyes occurring at approximately the same wavelength. It was observed that the permeation of the natural dyes were more uniform through the layers of the mesoporous TiO2 compared to the inorganic dye. Finally, defects and flaws on TiO2 film were easily recognized via surface profiling and 3D imaging of the films. The findings thus offer a new approach in characterization of dye sensitized solar cells.

  11. Improving Light Harvesting in Dye-Sensitized Solar Cells Using Hybrid Bimetallic Nanostructures

    DOE PAGESBeta

    Zarick, Holly F.; Erwin, William R.; Boulesbaa, Abdelaziz; Hurd, Olivia K.; Webb, Joseph A.; Puretzky, Alexander A.; Geohegan, David B.; Bardhan, Rizia

    2016-01-25

    In this paper, we demonstrate improved light trapping in dye-sensitized solar cells (DSSCs) with hybrid bimetallic gold core/silver shell nanostructures. Silica-coated bimetallic nanostructures (Au/Ag/SiO2 NSs) integrated in the active layer of DSSCs resulted in 7.51% power conversion efficiency relative to 5.97% for reference DSSCs, giving rise to 26% enhancement in device performance. DSSC efficiencies were governed by the particle density of Au/Ag/SiO2 NSs with best performing devices utilizing only 0.44 wt % of nanostructures. We performed transient absorption spectroscopy of DSSCs with variable concentrations of Au/Ag/SiO2 NSs and observed an increase in amplitude and decrease in lifetime with increasing particlemore » density relative to reference. Finally, we attributed this trend to plasmon resonant energy transfer and population of the singlet excited states of the sensitizer molecules at the optimum concentration of NSs promoting enhanced exciton generation and rapid charge transfer into TiO2.« less

  12. Incorporating hierarchical nanostructured carbon counter electrode into metal-free organic dye-sensitized solar cell.

    PubMed

    Fang, Baizeng; Fan, Sheng-Qiang; Kim, Jung Ho; Kim, Min-Sik; Kim, Minwoo; Chaudhari, Nitin K; Ko, Jaejung; Yu, Jong-Sung

    2010-07-01

    Hierarchical nanostructured carbon with a hollow macroporous core of ca. 60 nm in diameter in combination with mesoporous shell of ca. 30 nm in thickness has been explored as counter electrode in metal-free organic dye-sensitized solar cell. Compared with other porous carbon counterparts such as activated carbon and ordered mesoporous carbon CMK-3 and Pt counter electrode, the superior structural characteristics including large specific surface area and mesoporous volume and particularly the unique hierarchical core/shell nanostructure along with 3D large interconnected interstitial volume guarantee fast mass transport in hollow macroporous core/mesoporous shell carbon (HCMSC), and enable HCMSC to have highly enhanced catalytic activity toward the reduction of I(3)(-), and accordingly considerably improved photovoltaic performance. HCMSC exhibits a V(oc) of 0.74 V, which is 20 mV higher than that (i.e., 0.72 V) of Pt. In addition, it also demonstrates a fill factor of 0.67 and an energy conversion efficiency of 7.56%, which are markedly higher than those of its carbon counterparts and comparable to that of Pt (i.e., fill factor of 0.70 and conversion efficiency of 7.79%). Furthermore, HCMSC possesses excellent chemical stability in the liquid electrolyte containing I(-)/I(3)(-) redox couples, namely, after 60 days of aging, ca. 87% of its initial efficiency is still achieved by the solar cell based on HCMSC counter electrode. PMID:20334406

  13. Surfactant free most probable TiO2 nanostructures via hydrothermal and its dye sensitized solar cell properties

    PubMed Central

    Mali, Sawanta S.; Kim, Hyungjin; Shim, Chang Su; Patil, Pramod S.; Kim, Jin Hyeok; Hong, Chang Kook

    2013-01-01

    Tailoring the nano-morphology and nano-architecture of titanium dioxide (TiO2) is the most important task in the third generation solar cells (Dye sensitized solar cells/Quantum dot sensitized solar cells) (DSSCs/QDSSCs). In this article we present complete study of surfactant free synthesis of TiO2 nanostructures by a simple and promising hydrothermal route. The plethora of nanostructures like nanoparticles clusters, 1D tetragonal nanorods, 3D dendrites containing nanorods having <30 nm diameter and 3D hollow urchin like have been synthesized. These nanostructures possess effective large surface area and thus useful in DSSCs. In the present work, 7.16% power conversion efficiency has been demonstrated for 3D dendritic hollow urchin like morphology. Our synthetic strategy provides an effective solution for surfactant free synthesis of efficient TiO2 nanoarchitectures. PMID:24141599

  14. Synthesis of nanostructured CuInS2 thin films and their application in dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Zhao, Yu; Luo, Fazhi; Zhuang, Mixue; Liu, Zhen; Wei, Aixiang; Liu, Jun

    2016-03-01

    CuInS2 (CIS) nanostructure thin films were successfully synthesized on FTO conductive glass substrates by solvothermal method. It is found that the surface morphology and microstructure of CIS thin films can be tailored by simply adjusting the concentration of oxalic acid. CIS nanostructure films with texture of "nanosheet array" and "flower-like microsphere" were obtained and used as Pt-free counter electrode for dye-sensitized solar cells (DSSCs). The nanosheet array CIS was found to have a better electrocatalytic activity than the flower-like microsphere one. DSSCs based on nanosheet array CIS thin film counter electrode show conversion efficiency of 3.33 %, which is comparable to the Pt-catalyzed DSSCs. The easy synthesis, low cost, morphology tunable and excellent electrocatalytic property may make the CuInS2 nanostructure competitive as counter electrode in DSSCs.

  15. Dye Sensitized Solar Cells

    PubMed Central

    Wei, Di

    2010-01-01

    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. PMID:20480003

  16. Dye sensitized solar cells.

    PubMed

    Wei, Di

    2010-01-01

    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 TiO(2), ZnO electrodes, ionic liquid electrolytes, carbon nanotubes, graphene and solid state DSSC have all been included and discussed. PMID:20480003

  17. Enhanced photovoltaic properties of dye-sensitized solar cell based on ultrathin 2D TiO2 nanostructures

    NASA Astrophysics Data System (ADS)

    Zhang, Putao; Hu, Zhiqiang; Wang, Yan; Qin, Yiying; Sun, Xiao Wei; Li, Wenqin; Wang, Jinmin

    2016-04-01

    Ultrathin two-dimensional (2D) TiO2 nanostructures with a thickness of ∼5 nm and a specific surface area of 257.3 m2 g-1 were synthesized by a hydrothermal process. The 2D TiO2 nanostructures and P25 nanoparticles were introduced as scattering layer and underlayer to construct a bi-layer photoanode in a dye-sensitized solar cell (DSSC). The as-prepared DSSC exhibits an enhanced power conversion efficiency (5.14%), which is 23.9% higher than that of pure P25 DSSC (4.15%). Electrochemical impedance spectroscopy (EIS) indicates that DSSC based on P25-2D TiO2 nanostructures shows a longer life time and a larger recombination resistance. The enhanced photovoltaic properties are attributed to the excellent light scattering capability and high capacity for dye adsorption of 2D TiO2 nanostructures, which makes them a promising candidate as an efficient scattering layer in high-performance DSSCs.

  18. "Secondary Growth" in Hydrothermal Synthesis of Aligned ZnO Nanostructures and Its Application in Dye-Sensitized Solar Cells.

    PubMed

    Liu, Wenjun; Huang, Qiaoling; Huang, Tengji; Cao, Peijiang; Han, Shun; Jia, Fang; Zhu, Deliang; Ma, Xiaocui; Lul, Youming

    2016-04-01

    One-dimensional (1D) aligned ZnO nanostructures were prepared on ZnO film seeded substrates using a low-temperature hydrothermal method, and zinc nitrate and hexamethylenetetramine (HMT) precursors. It was observed that increasing the concentration ratio of Zn2+/HMT from 1 to 100 led to a "secondary growth," and a change in the morphologies of the ZnO nanostructures from arrays of thick nanorods to arrays of thin nanorod-step-thick nanorods. The morphological evolution of ZnO nanostructures with increased growth time at high Zn2+/HMT concentration ratios showed the same transformation. Dye-sensitized solar cells (DSSCs) were fabricated using ZnO nanostructures as the photoanodes, and the electron transport properties were determined by electrochemical impedance spectroscopy (EIS). Although the DSSCs showed low power conversion efficiencies due to the short lengths, the arrays of the thin nanorods demonstrated excellent electron transport with an electron diffusion coefficient (Dn) of 1.57 x 10(-3) cm2/s, and an effective diffusion length (L) of 140 µm. PMID:27451759

  19. Hierarchical Oriented Anatase TiO2 Nanostructure arrays on Flexible Substrate for Efficient Dye-sensitized Solar Cells

    NASA Astrophysics Data System (ADS)

    Wu, Wu-Qiang; Rao, Hua-Shang; Xu, Yang-Fan; Wang, Yu-Fen; Su, Cheng-Yong; Kuang, Dai-Bin

    2013-05-01

    The vertically oriented anatase single crystalline TiO2 nanostructure arrays (TNAs) consisting of TiO2 truncated octahedrons with exposed {001} facets or hierarchical TiO2 nanotubes (HNTs) consisting of numerous nanocrystals on Ti-foil substrate were synthesized via a two-step hydrothermal growth process. The first step hydrothermal reaction of Ti foil and NaOH leads to the formation of H-titanate nanowire arrays, which is further performed the second step hydrothermal reaction to obtain the oriented anatase single crystalline TiO2 nanostructures such as TiO2 nanoarrays assembly with truncated octahedral TiO2 nanocrystals in the presence of NH4F aqueous or hierarchical TiO2 nanotubes with walls made of nanocrystals in the presence of pure water. Subsequently, these TiO2 nanostructures were utilized to produce dye-sensitized solar cells in a backside illumination pattern, yielding a significant high power conversion efficiency (PCE) of 4.66% (TNAs, JSC = 7.46 mA cm-2, VOC = 839 mV, FF = 0.75) and 5.84% (HNTs, JSC = 10.02 mA cm-2, VOC = 817 mV, FF = 0.72), respectively.

  20. Growth of Comb-like ZnO Nanostructures for Dye-sensitized Solar Cells Applications

    PubMed Central

    2009-01-01

    Dye-sensitized solar cells (DSSCs) were fabricated by using well-crystallized ZnO nanocombs directly grown onto the fluorine-doped tin oxide (FTO) via noncatalytic thermal evaporation process. The thin films of as-grown ZnO nanocombs were used as photoanode materials to fabricate the DSSCs, which exhibited an overall light to electricity conversion efficiency of 0.68% with a fill factor of 34%, short-circuit current of 3.14 mA/cm2, and open-circuit voltage of 0.671 V. To the best of our knowledge, this is first report in which thin film of ZnO nanocombs was used as photoanode materials to fabricate the DSSCs. PMID:20596445

  1. Significant enhancement of power conversion efficiency for dye sensitized solar cell using 1D/3D network nanostructures as photoanodes

    NASA Astrophysics Data System (ADS)

    Wang, Hao; Wang, Baoyuan; Yu, Jichao; Hu, Yunxia; Xia, Chen; Zhang, Jun; Liu, Rong

    2015-03-01

    The single-crystalline TiO2 nanorod arrays with rutile phase have attracted much attention in the dye sensitized solar cells (DSSCs) applications because of their superior chemical stability, better electron transport properties, higher refractive index and low production cost. However, it suffers from a low surface area as compared with TiO2 nanoparticle films. In order to enlarge the surface area of TiO2 nanorod arrays, the 1D nanorods/3D nanotubes sample was synthesized using a facile two-step hydrothermal process involving hydrothermal growth 1D/3D nanorods and followed by post-etching treatment. In such bi-layer structure, the oriented TiO2 nanorods layer could provide direct pathway for fast electron transportation, and the 3D nanotubes layer offers a higher surface area for dye loading, therefore, the 1D nanorods/3D nanotubes photoanode exhibited faster electron transport and higher surface area than either 1D or 3D nanostructures alone, and an highest efficiency of 7.68% was achieved for the DSSCs based on 1D nanorods/3D nanotubes photoanode with further TiCl4 treatment.

  2. Influence of niobium doping in hierarchically organized titania nanostructure on performance of dye-sensitized solar cells.

    PubMed

    Park, Jong Hoon; Noh, Jun Hong; Han, Byung Suh; Shin, Seong Sik; Park, Ik Jae; Kim, Dong Hoe; Hong, Kug Sun

    2012-06-01

    Niobium doped hierarchically organized TiO2 nanostructures composed of 20 nm size anatase nanocrystals were synthesized using pulsed laser deposition (PLD). The Nb doping concentration could be facilely controlled by adjusting the concentration of Nb in target materials. We could investigate the influence of Nb doping in the TiO2 photoelectrode on the cell performance of dye-sensitized solar cells (DSSCs) by the exclusion of morphological effects using the prepared Nb-doped TiO2 anostructures. We found no significant change in short circuit current density (Jsc) as a function of Nb doping concentration. However, open circuit voltage (Voc) and fill factor (FF) monotonously decrease with increasing Nb concentration. Dark current characteristics of the DSSCs reveal that the decrease in Voc and FF is attributed to the decrease in shunt resistance due to the increase in conductivity TiO2 by Nb doping. However, electrochemical impedance spectra (EIS) analysis at open circuit condition under illumination showed that the resistance at the TiO2/dye/electrolyte interface increases with Nb concentration, revealing that Nb doping suppress the charge recombination at the interface. In addition, electron life time obtained using characteristic frequency in Bode plot increases from 14 msec to 56 msec with increasing Nb concentration from 0 to 1.2 at%. This implies that the improved light harvesting can be achieved by increasing diffusion length through Nb-doping in the conventional TiO2 photoelectrode. PMID:22905583

  3. Significant enhancement of power conversion efficiency for dye sensitized solar cell using 1D/3D network nanostructures as photoanodes

    PubMed Central

    Wang, Hao; Wang, Baoyuan; Yu, Jichao; Hu, Yunxia; Xia, Chen; Zhang, Jun; Liu, Rong

    2015-01-01

    The single–crystalline TiO2 nanorod arrays with rutile phase have attracted much attention in the dye sensitized solar cells (DSSCs) applications because of their superior chemical stability, better electron transport properties, higher refractive index and low production cost. However, it suffers from a low surface area as compared with TiO2 nanoparticle films. In order to enlarge the surface area of TiO2 nanorod arrays, the 1D nanorods/3D nanotubes sample was synthesized using a facile two-step hydrothermal process involving hydrothermal growth 1D/3D nanorods and followed by post-etching treatment. In such bi-layer structure, the oriented TiO2 nanorods layer could provide direct pathway for fast electron transportation, and the 3D nanotubes layer offers a higher surface area for dye loading, therefore, the 1D nanorods/3D nanotubes photoanode exhibited faster electron transport and higher surface area than either 1D or 3D nanostructures alone, and an highest efficiency of 7.68% was achieved for the DSSCs based on 1D nanorods/3D nanotubes photoanode with further TiCl4 treatment. PMID:25800933

  4. Significant enhancement of power conversion efficiency for dye sensitized solar cell using 1D/3D network nanostructures as photoanodes.

    PubMed

    Wang, Hao; Wang, Baoyuan; Yu, Jichao; Hu, Yunxia; Xia, Chen; Zhang, Jun; Liu, Rong

    2015-01-01

    The single-crystalline TiO2 nanorod arrays with rutile phase have attracted much attention in the dye sensitized solar cells (DSSCs) applications because of their superior chemical stability, better electron transport properties, higher refractive index and low production cost. However, it suffers from a low surface area as compared with TiO2 nanoparticle films. In order to enlarge the surface area of TiO2 nanorod arrays, the 1D nanorods/3D nanotubes sample was synthesized using a facile two-step hydrothermal process involving hydrothermal growth 1D/3D nanorods and followed by post-etching treatment. In such bi-layer structure, the oriented TiO2 nanorods layer could provide direct pathway for fast electron transportation, and the 3D nanotubes layer offers a higher surface area for dye loading, therefore, the 1D nanorods/3D nanotubes photoanode exhibited faster electron transport and higher surface area than either 1D or 3D nanostructures alone, and an highest efficiency of 7.68% was achieved for the DSSCs based on 1D nanorods/3D nanotubes photoanode with further TiCl4 treatment. PMID:25800933

  5. Hydrothermal growth and characterization of titanium dioxide nanostructures for use in dye sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Sorge, Judith D.

    As the world's energy needs continue to grow, next generation photovoltaic cells are in high demand because they offer the possibility of an inexpensive alternative to current energy production techniques. Dye sensitized solar cells (DSSC's), utilize common materials and low cost commercialization techniques, which make them a compelling choice for research in this area. This research focuses on the titanium dioxide coating, which transfers electrons from the photoactive dye to the electrode. 3-4% efficient DSSC's using doctor bladed titanium dioxide coatings with a specific surface area of 55-60m2/g have been demonstrated in our laboratory. To enhance the efficiency of these cells, both the surface area and the electron conduction of the titania layer must be optimized. This has been done by utilizing high aspect ratio nanoparticles of titania instead of mesoporous layers formed with spherical particles. Anodization of titanium metal or anodic alumina membrane templating are common ways to produce nanorods, but involve complex processes leading toward expensive commercialization. This research instead focuses on the hydrothermal growth of nanofibrous titania on a titanium metal substrate, removing the need for dispersion and deposition procedures as well as using a low temperature processing method. Depending upon the formulation utilized, a variety of structures can be produced, from thick carpets of nanofiber strands to large platelets. The composition and morphology of the products have been characterized with respect to the growth conditions using electron microscopy, energy dispersive spectroscopy and x-ray diffraction. The compositional analysis is used to investigate the complicated reaction mechanisms in the system. Coatings of titania nanotubes were then tested in the DSSC's, as were those with the titanium metal substrate acting as the photo anode. Modeling the geometric parameters of the different pore structures of the coatings helps us to understand

  6. Nanostructure control of graphene-composited TiO2 by a one-step solvothermal approach for high performance dye-sensitized solar cells.

    PubMed

    He, Ziming; Guai, Guanhong; Liu, Jing; Guo, Chunxian; Loo, Joachim Say Chye; Li, Chang Ming; Tan, Timothy Thatt Yang

    2011-11-01

    We present a one-step solvothermal approach to prepare uniform graphene-TiO(2) nanocomposites with delicately controlled TiO(2) nanostructures, including ultra-small 2 nm nanoparticles, 12 nm nanoparticles and nanorods. Using three composites as photoanode materials, the effect of nanostructure of graphene-composited TiO(2) on the performance of dye-sensitized solar cells was investigated, and results showed that the ultra-small 2 nm TiO(2)-graphene composite based photoanode exhibited the highest power conversion efficiency of 7.25%. PMID:22006266

  7. Efficiency enhancement of cubic perovskite BaSnO3 nanostructures based dye sensitized solar cells.

    PubMed

    Rajamanickam, N; Soundarrajan, P; Vendra, Venkat K; Jasinski, Jacek B; Sunkara, Mahendra K; Ramachandran, K

    2016-03-28

    Cubic perovskite BaSnO3 (BSO) is an important photoelectron transporting material due to its electronic structure that competes with TiO2 in dye-sensitized solar cells (DSCs). Separately, BSO/TiCl4 treated and BSO/scattering layer photoelectrodes have been used in DSCs that effectively increase the photoexcited charge carriers collection resulting in superior photovoltaic performance. In the present work, the different TiCl4 treatment time (1, 3 and 5 min), different scattering layer (tetragonal anatase TiO2 and hexagonal wurtzite ZnO) and different combinations thereof are successfully used on BSO nanocuboids/nanoparticle morphological structure photoelectrodes, and then we systematically inspected their performance in DSCs. Under the optimized conditions, a power conversion efficiency (PCE) of 3.88% is obtained by a BSO/TiCl4 treated photoanode. Furthermore, the BSO photoanodes made using a scattering layer such as anatase TiO2 and hexagonal ZnO i.e., BSO/anatase TiO2 and BSO/hexagonal ZnO, exhibited PCEs of 1.14% and 1.25% respectively. In the end, one of the highest PCEs (5.68%) was achieved using BSO/TiCl4 treated/TiO2 scattering layer photoanode. Another photoelectrode such as BSO/TiCl4 treated/ZnO scattering layer exhibited a PCE of 4.28% that is also higher than the BSO/TiCl4 treated/BSO scattering layer photoanodes. Electron lifetime versus current density studies illustrate the stability of the BSO photoelectrode in DSCs. From the observed results, it is realized that BSO is one of the most important future technological materials. PMID:26935818

  8. Nanostructure control of graphene-composited TiO2 by a one-step solvothermal approach for high performance dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    He, Ziming; Guai, Guanhong; Liu, Jing; Guo, Chunxian; Chye Loo, Joachim Say; Li, Chang Ming; Tan, Timothy Thatt Yang

    2011-11-01

    We present a one-step solvothermal approach to prepare uniform graphene-TiO2 nanocomposites with delicately controlled TiO2 nanostructures, including ultra-small 2 nm nanoparticles, 12 nm nanoparticles and nanorods. Using three composites as photoanode materials, the effect of nanostructure of graphene-composited TiO2 on the performance of dye-sensitized solar cells was investigated, and results showed that the ultra-small 2 nm TiO2-graphene composite based photoanode exhibited the highest power conversion efficiency of 7.25%.We present a one-step solvothermal approach to prepare uniform graphene-TiO2 nanocomposites with delicately controlled TiO2 nanostructures, including ultra-small 2 nm nanoparticles, 12 nm nanoparticles and nanorods. Using three composites as photoanode materials, the effect of nanostructure of graphene-composited TiO2 on the performance of dye-sensitized solar cells was investigated, and results showed that the ultra-small 2 nm TiO2-graphene composite based photoanode exhibited the highest power conversion efficiency of 7.25%. Electronic supplementary information (ESI) available: Detailed experimental procedures, AFM images, SEM images, J-V curves for optimization, and tables containing EDX results, BET results and calculation data. See DOI: 10.1039/c1nr11300c

  9. Solar energy conversion at dye sensitized nanostructured electrodes fabricated by sol-gel processing: Final report

    SciTech Connect

    Searson, P C; Meyer, G J

    1998-07-01

    The significant achievements accomplished in this program include: (1) the first demonstration of osmium polypyridyl compounds as sensitizers; (2) the first demonstration of donor-acceptor compounds as sensitizers; (3) the first utilization of alternative acac based sensitizer-semiconductor linkages; (4) the first demonstration of remote interfacial electron transfer; (5) the first application of bimetallic compounds as sensitizers; (6) the first correlation of the interfacial charge recombination rate constant with the open circuit photovoltage in sensitized materials; (7) the first demonstration of a solid state dye sensitized TiO{sub 2} cell; (8) an alternative band edge unpinning model for the nanocrystalline TiO{sub 2}/electrolyte interface at negative applied potentials; and (9) the first self-consistent model of electron transport in dye sensitized TiO{sub 2} films. In the following sections the authors summarize some of the results from this program and highlight the key findings.

  10. Investigation of effect of anti-aggregation agent on the performance of nanostructure dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Hosseinnezhad, M.; Moradian, S.; Gharanjig, K.

    2015-06-01

    Dye sensitized solar cells (DSSCs) based on indigo dyes exhibit suitable conversion efficiency. These organic dyes have been undergone for aggregation. Electron transfer process is reduced due to an aggregation of molecular dyes. Therefore, anti-aggregation agent is commonly utilized in fabrication of DSSCs. In the present study, two anti-aggregation agents namely as 3α,7α-dihydroxy-5β-cholanic acid (cheno) and 3α,7α,12α-trihydroxy-5β-cholanic acid (cholic acid) were added to indigo dye solution in DSSCs in order to determine the photovoltaic parameters such as short circuit photocurrent, open circuit voltage and conversion efficiency of each individual dye in the absence and presence of anti-aggregation agents. The results show that the conversion efficiencies are improved with reduced aggregation. Spectrophotometric evaluations of the indigo dyes in solution and on a TiO2 substrate were carried out in the absence and presence of anti-aggregation agents in order to estimate changes in the status of the dyes in different environments. J-type aggregates on the nano TiO2 are reduced in the presence of anti-aggregation agents.

  11. Surfactant mediated one- and two-dimensional ZnO nanostructured thin films for dye sensitized solar cell application

    NASA Astrophysics Data System (ADS)

    Marimuthu, T.; Anandhan, N.; Thangamuthu, R.; Mummoorthi, M.; Rajendran, S.; Ravi, G.

    2015-01-01

    One-dimensional (1D) and two-dimensional (2D) nanostructured zinc oxide (ZnO) thin films were electrodeposited from aqueous zinc chloride on FTO glass substrates. The effects of organic surfactant such as cetyltrimethyl ammonium bromide (CTAB) and polyvinyl alcohol (PVA) on structural, morphological, crystal quality and optical properties of electrodeposited ZnO films were investigated. The x-ray diffraction pattern revealed that the prepared thin films were pure wutrzite hexagonal structure. The thin films deposited using organic surfactant in this work showed different morphologies such as nanoplatelet and flower. The hexagonal platelet and flower-like nanostructures were obtained in the presence of CTAB and PVA surfactant, respectively. The crystal quality and atomic vacancies of the prepared nanostructured thin films were investigated by micro Raman spectroscopic technique. The emission properties and optical quality of the films were studied by photoluminescence spectrometry. PEMA-LiClO4-EC gel polymer electrolyte has been used to replace the liquid electrolyte for reducing the leakage problem. Graphene counter electrode was used as an alternative for platinum electrode. Eosin yellow dye was used as a sensitizer. J-V characterizations were carried out for different 1D and 2D nanostructures. The nanoflower structure exhibited higher efficiency (η = 0.073%) than the other two nanostructures.

  12. Photochemical performance of ZnO nanostructures in dye sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Das, Partha Pratim; Mukhopadhyay, Soumita; Agarkar, Shruti A.; Jana, Arpita; Devi, P. Sujatha

    2015-10-01

    In this work, the photoconversion efficiencies of ZnO having diverse microstructures and structural defects have been investigated. A conversion efficiency of 1.38% was achieved for the DSSCs fabricated with as prepared ZnO nanorods having minimum vacancy defects and a favourable one dimensional directional pathway for electron conduction. The DSSCs fabricated with ZnO nanoparticles exhibited relatively low conversion efficiency of 1.004% probably due to multiple trapping/detrapping phenomena within the grain boundaries and ZnO flowers though exhibited a high dye adsorption capability exhibited the lowest conversion efficiency of 0.59% due to a high concentration of structural defects. Based on the experimental evidences, we believe that the type of defects and their concentrations are more important than shape in controlling the overall performance of ZnO based DSSCs.

  13. EDITORIAL: Nanostructured solar cells Nanostructured solar cells

    NASA Astrophysics Data System (ADS)

    Greenham, Neil C.; Grätzel, Michael

    2008-10-01

    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

  14. Anthocyanin extracted from Hibiscus (Hibiscus rosa sinensis L.) as a photosensitizer on nanostructured-TiO2 dye sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Ramelan, A. H.; Wahyuningsih, S.; Rosyida, N. A.; Supriyanto, E.; Saputro, S.; Hanif, Q. A.; Rinawati, L.

    2016-02-01

    Anthocyanin extracted from Hibiscus (Hibiscus rosa sinensis L) as a photosensitizer in nanostructured-TiO2 dye sensitized solar cells has been fabricated. Ultravisible visible absorption spectra of anthocyanin show an ability absorbing light in the visible region. While the nanostructed-TiO2 powder in this research was prepared by sol-gel method following annealled at a temperature of 600°C. Subsequently, the TiO2 nanostructures were characterized by XRD, XRF, and SEM. The difractogram X-ray results shown that TiO2 was built from f anatase and rutile phase. Element analysis of synthesized TiO2 by X-ray Fluorecence (XRF) shown the TiO2 content of 98,67 wt%. TiO2 layer prepared at different thickness showed the average size of cavity about 0.83 µm. These several thickness of solar cells were fabricated and were immersed into anthocyanin for 24 hours to gain sensitized TiO2 photoanode for Dye sensitised solar cells (DSSCs). These DSSCS performance were measured using I-V Keithley 2602A. The results exhibited that the sample with a TiO2 layer thickness of 4.75 ± 0.8 µm has the highest efficiency.

  15. Tin sulfide (SnS) nanostructured films deposited by continuous spray pyrolysis (CoSP) technique for dye-sensitized solar cells applications

    NASA Astrophysics Data System (ADS)

    Alam, Firoz; Dutta, Viresh

    2015-12-01

    Tin sulfide (SnS) nanostructured films have been deposited on transparent conducting glass substrate using continuous spray pyrolysis (CoSP) technique using aqueous spray solution of tin chloride and thiourea. Structural, morphological and optical properties of as-synthesized SnS nanostructured films showed the formation of (1 0 1) oriented orthorhombic SnS with nanoflakes having a direct band gap of 1.40 eV. X-ray photoelectron spectroscopy (XPS) analysis confirms the formation of pure SnS with Sn in +2 oxidation state. The SnS nanostructured film has also been characterized using Brunauer-Emmett-Teller (BET) technique to determine the surface area and pore volume which are found to be 11.4 m2/g and 0.02 cm2/g, respectively. The film has been used as a counter electrode (CE) in a triiodide/iodide (I3-/I-) based dye-sensitized solar cells (DSSCs). The DSSCs of 0.25 cm2 area with SnS nanostructured CE exhibits a lower power conversion efficiency (2.0 ± 0.06%) than that for the cell with standard platinum (Pt) CE (4.5 ± 0.13%). However, the usefulness of the CoSP technique for deposition of nanostructures SnS CE film has been established in the present study.

  16. Pt-free and efficient counter electrode with nanostructured CoNi2S4 for dye-sensitized solar cells

    PubMed Central

    Shi, Zhiwei; Deng, Kaimo; Li, Liang

    2015-01-01

    The counter electrode has a great influence on the performance of the dye-sensitized solar cells (DSSCs). The research and development of Pt-free counter electrode is becoming one of the hot areas in the field of DSSCs. Herein, we successfully synthesized a ternary metal sulfide (CoNi2S4) nanostructure on FTO substrate by hydrothermal method and investigated its application as counter electrode. The as-synthesized sample could exhibit better electrocatalystic property than that of Pt, and corresponding DSSCs have comparable conversion efficiency with typical Pt catalyzed cells. The easy synthesis, low cost and excellent electrocatalytic property may help the CoNi2S4 nanostructure stand out as an alternative counter electrode in DSSCs. PMID:25799125

  17. Improving Electron Transfer from Dye to TiO2 by Using CdTe Nanostructure Layers in Dye-Sensitized Solar Cells

    NASA Astrophysics Data System (ADS)

    Beshkar, Farshad; Sabet, Mohammad; Salavati-Niasari, Masoud

    2015-08-01

    In this work, TiO2 P25 was deposited successfully on the FTO glass by electrophoresis method. Different chemical methods were served for deposition of nanosized CdTe such as successive ion layer adsorption and reaction (SILAR) and drop-cast. Dye-sensitized solar cells were fabricated from prepared electrodes, Pt as a counter electrode, dye solution, and electrolyte. The effects of chemical deposition methods were investigated on the surface quality, optical properties, and solar cell efficiency. It was observed that deposition method has an important role on the solar cell performance. It was also seen that deposition method affects directly on surface thickness and the amount of dye adsorption. In fact, each deposition method creates different surfaces, and hence, they act variously in electron transfer across the electrode surface. Among different deposition methods that were used in this experimental work, SILAR method showed the best performance and the surface that was created by this method could transfer the electrons across the electrode faster than the other ones. But this chemical method cannot improve solar cell efficiency due to some different reasons that we mentioned in this paper.

  18. Efficient NiSe-Ni3Se2/Graphene Electrocatalyst in Dye-Sensitized Solar Cells: The Role of Hollow Hybrid Nanostructure.

    PubMed

    Zhang, Xiao; Zhen, Mengmeng; Bai, Jinwu; Jin, Shaowei; Liu, Lu

    2016-07-13

    Hollow and hybrid nanomaterials are excellent electrocatalysts on account of their novel electrocatalytic properties compared with homogeneous solid nanostructures. In this report, NiSe-Ni3Se2 hybrid nanostructure with morphology of hollow hexagonal nanodisk was synthesized in situ on graphene. A series of NiSe-Ni3Se2/RGO with different phase constitutions and nanostructures were obtained by controlling the durations of solvothermal treatment. Because of their unique hollow and hybrid structure, NiSe-Ni3Se2/RGO hollow nanodisks exhibited higher electrocatalytic performance than NiSe/RGO and solid NiSe-Ni3Se2/RGO nanostructure for reducing I3(-) as counter cell (CE) of dye-sensitized solar cells (DSSCs). Additionally, NiSe-Ni3Se2/RGO hollow nanodisks achieved much lower charge transfer resistance (Rct = 0.68 Ω) and higher power conversion efficiency (PCE) (7.87%) than those of Pt (Rct = 1.41 Ω, PCE = 7.28%). PMID:27314283

  19. Improved electron transfer and plasmonic effect in dye-sensitized solar cells with bi-functional Nb-doped TiO2/Ag ternary nanostructures.

    PubMed

    Park, Jung Tae; Chi, Won Seok; Jeon, Harim; Kim, Jong Hak

    2014-03-01

    TiO2 nanoparticles are surface-modified via atom transfer radical polymerization (ATRP) with a hydrophilic poly(oxyethylene)methacrylate (POEM), which can coordinate to the Ag precursor, i.e. silver trifluoromethanesulfonate (AgCF3SO3). Following the reduction of Ag ions, a Nb2O5 doping process and calcination at 450 °C, bi-functional Nb-doped TiO2/Ag ternary nanostructures are generated. The resulting nanostructures are characterized by energy-filtering transmission electron microscopy (EF-TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and UV-visible spectroscopy. The dye-sensitized solar cell (DSSC) based on the Nb-doped TiO2/Ag nanostructure photoanode with a polymerized ionic liquid (PIL) as the solid polymer electrolyte shows an overall energy conversion efficiency (η) of 6.9%, which is much higher than those of neat TiO2 (4.7%) and Nb-doped TiO2 (5.4%). The enhancement of η is mostly due to the increase of current density, attributed to the improved electron transfer properties including electron injection, collection, and plasmonic effects without the negative effects of charge recombination or problems with corrosion. These properties are supported by intensity modulated photocurrent/voltage spectroscopy (IMPS/IMVS) and incident photon-to-electron conversion efficiency (IPCE) measurements. PMID:24457831

  20. Our Expedition in Linear Neutral Platinum-Acetylide Complexes: The Preparation of Micro/nanostructure Materials, Complicated Topologies, and Dye-Sensitized Solar Cells.

    PubMed

    Xu, Lin; Yang, Hai-Bo

    2016-06-01

    During the past few decades, the construction of various kinds of platinum-acetylide complexes has attracted considerable attention, because of their wide applications in photovoltaic cells, non-linear optics, and bio-imaging materials. Among these platinum-acetylide complexes, the linear neutral platinum-acetylide complexes, due to their attractive properties, such as well-defined linear geometry, synthetic accessibility, and intriguing photoproperties, have emerged as a rising star in this field. In this personal account, we will discuss how we entered the field of linear neutral platinum-acetylide chemistry and what we found in this field. The preparation of various types of linear neutral platinum-acetylide complexes and their applications in the areas of micro/nanostructure materials, complicated topologies, and dye-sensitized solar cells will be summarized in this account. PMID:27097565

  1. Holographic modification of TiO2 nanostructure for enhanced charge transport in dye-sensitized solar cell

    NASA Astrophysics Data System (ADS)

    Lee, Jinsoo; Yoon, Junghwan; Jin, Minhea; Lee, Myeongkyu

    2012-08-01

    We show that the photocurrent and energy conversion efficiency of dye-sensitized solar cells can be greatly enhanced with holographic modification to the morphology of TiO2 electrode. The nanoporous electrode coated onto conducting glass was irradiated by three interfering laser beams at 1064 nm incident from the backside of the substrate. This generated two-dimensional periodic pillars of higher density in the electrode, through which the photoexcited electrons could be extracted more effectively. The cells fabricated with modified electrodes exhibited average photocurrent and efficiency of 17.14 mA/cm2 and 9.03%, while 14.91 mA/cm2 and 7.83% were obtained from the reference cells. It was attributed to the enhanced charge transport accompanied by the reduction of internal resistance of the electrode.

  2. Holographic modification of TiO{sub 2} nanostructure for enhanced charge transport in dye-sensitized solar cell

    SciTech Connect

    Lee, Jinsoo; Yoon, Junghwan; Jin, Minhea; Lee, Myeongkyu

    2012-08-15

    We show that the photocurrent and energy conversion efficiency of dye-sensitized solar cells can be greatly enhanced with holographic modification to the morphology of TiO{sub 2} electrode. The nanoporous electrode coated onto conducting glass was irradiated by three interfering laser beams at 1064 nm incident from the backside of the substrate. This generated two-dimensional periodic pillars of higher density in the electrode, through which the photoexcited electrons could be extracted more effectively. The cells fabricated with modified electrodes exhibited average photocurrent and efficiency of 17.14 mA/cm{sup 2} and 9.03%, while 14.91 mA/cm{sup 2} and 7.83% were obtained from the reference cells. It was attributed to the enhanced charge transport accompanied by the reduction of internal resistance of the electrode.

  3. The effect of substrate temperature on the spray-deposited TiO2 nanostructured films for dye-sensitized solar cells.

    PubMed

    Hossain, Md Faruk; Takahashi, Takakazu

    2011-04-01

    The nanostructured TiO2 films have deposited on SnO2:F (FTO) coated glass substrate by spray pyrolysis technique at different substrate temperatures of 200-500 degrees C. The structural, surface morphological and optical properties of TiO2 films significantly vary with the substrate temperature. The surface of the TiO2 films deposited at 400 degrees C shows the nanoflakes and short nanorods (approximately 130 nm) like structures while the TiO2 films prepared at 500 degrees C shows only the nanoflakes like structures. The band gap of the TiO2 films prepared at higher temperatures (300-500 degrees C) becomes narrow due to presence the rutile phases in their crystal structure. Ruthenium (II) complex as a dye, KI/I2 as an electrolyte and carbon on FTO glass as a counter electrode has used to fabricate the dye-sensitized solar cell (DSC). The TiO2 film deposited at 400 degrees C has showed the best photovoltaic performance in DSC with the efficiency of 3.81%, the photovoltage of 773 mV, the photocurrent of 8.34 mA/cm2, and the fill factor of 56.17%. The photovoltage of the DSC increases with the increase of substrate temperature during the deposition of TiO2 films. Moreover, all the DSCs exhibit reasonably high fill factor value. PMID:21776690

  4. Facile synthesis of ZnO micro-nanostructures with controllable morphology and their applications in dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Zhou, Yi; Li, Dang; Zhang, Xiangchao; Chen, Jianlin; Zhang, Shiying

    2012-11-01

    Different morphologies of ZnO micro-nanostructures were successfully prepared by hydrothermal method at relatively mild conditions using ammonia to adjust the pH of the reaction system. The samples were characterized by X-ray powder diffraction, scanning electron microscopy, optical reflectance spectra, and photocurrent-voltage curve. The results demonstrated that the morphologies of ZnO changed from "wire" to "flower", "urchin" and "wire" with increase in the pH of the reaction system due to the increased concentration of ammonia. The diffused reflectance spectra illustrated that the reflectance of denser urchin-like ZnO was low at 18% in the visible region. When the as-synthesized ZnO micro-nanostructures were used as the anode of the dye sensitization solar cell, the denser urchin-like ZnO exhibited the best photoelectric properties. The short circuit current (Jsc), open circuit voltage (Voc), and conversion efficiency (η) were 6.50 mA/cm2, 0.682 V, and 1.92%, respectively.

  5. Improved electron transfer and plasmonic effect in dye-sensitized solar cells with bi-functional Nb-doped TiO2/Ag ternary nanostructures

    NASA Astrophysics Data System (ADS)

    Park, Jung Tae; Chi, Won Seok; Jeon, Harim; Kim, Jong Hak

    2014-02-01

    TiO2 nanoparticles are surface-modified via atom transfer radical polymerization (ATRP) with a hydrophilic poly(oxyethylene)methacrylate (POEM), which can coordinate to the Ag precursor, i.e. silver trifluoromethanesulfonate (AgCF3SO3). Following the reduction of Ag ions, a Nb2O5 doping process and calcination at 450 °C, bi-functional Nb-doped TiO2/Ag ternary nanostructures are generated. The resulting nanostructures are characterized by energy-filtering transmission electron microscopy (EF-TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and UV-visible spectroscopy. The dye-sensitized solar cell (DSSC) based on the Nb-doped TiO2/Ag nanostructure photoanode with a polymerized ionic liquid (PIL) as the solid polymer electrolyte shows an overall energy conversion efficiency (η) of 6.9%, which is much higher than those of neat TiO2 (4.7%) and Nb-doped TiO2 (5.4%). The enhancement of η is mostly due to the increase of current density, attributed to the improved electron transfer properties including electron injection, collection, and plasmonic effects without the negative effects of charge recombination or problems with corrosion. These properties are supported by intensity modulated photocurrent/voltage spectroscopy (IMPS/IMVS) and incident photon-to-electron conversion efficiency (IPCE) measurements.TiO2 nanoparticles are surface-modified via atom transfer radical polymerization (ATRP) with a hydrophilic poly(oxyethylene)methacrylate (POEM), which can coordinate to the Ag precursor, i.e. silver trifluoromethanesulfonate (AgCF3SO3). Following the reduction of Ag ions, a Nb2O5 doping process and calcination at 450 °C, bi-functional Nb-doped TiO2/Ag ternary nanostructures are generated. The resulting nanostructures are characterized by energy-filtering transmission electron microscopy (EF-TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and UV-visible spectroscopy. The dye-sensitized solar cell (DSSC) based on the Nb

  6. Nanostructured TiO2 films for dye-sensitized solar cells prepared by the sol-gel method.

    PubMed

    Jin, Young Sam; Kim, Kyung Hwan; Park, Sang Joon; Yoon, Hyon Hee; Choi, Hyung Wook

    2011-12-01

    TiO2 films were prepared on glass substrates using the sol-gel process for a dye-sensitized solar cell application. The TiO2 sol was prepared using hydrolysis/polycondensation. Titanium (IV) Tetra Isopropoxide (TTIP) was used as precursor and Nitric acid (HNO3) was used as a catalyst for the peptization. The crystal structure and morphology of the prepared materials were characterized by XRD, and an SEM. The observations confirmed the nanocrystalline nature of the TiO2. The reaction parameters, such as the catalyst concentrations, the calcination time, and the calcination temperature were varied during the synthesis in order to achieve nanosize TiO2 particles. The prepared TiO2 particles were coated onto FTO glass using a screen printing technique. The prepared TiO2 films were characterized by UV-vis. The TiO2 particles calcinated at low temperatures showed an anatase phase they grew into a rutile phase when the calcination temperature increased. The size and structure of the TiO2 particles were adjusted to specific surface areas. It was found that the conversion efficiency of the DSSC was highly affected by the properties of the TiO2 particles. PMID:22409037

  7. Effect of growth solution concentration on the performance of gallium doped ZnO nanostructures dye sensitized solar cells (DSSCs)

    NASA Astrophysics Data System (ADS)

    Iwantono, I.; Tugirin, S.; Anggelina, F.; Awitdrus, Taer, Erman; Roza, L.; Umar, A. A.

    2016-02-01

    This paper reports the synthesis of gallium doped ZnO nanostructures via seed mediated growth hydrothermal technique and their application as photo-anode in DSSC. ZnO nanostructures have been grown on Flourin Tin Oxide (FTO). The precursor used in this research was zinc-nitrate-hexahydrate (Zn (NO3)2.6H2O) and hexa-metylene-tetramine (HMT) was chosen as surfactant. The growth process was carried out at various precursor solution concentrations, 0.1, 0.2, 0.3 and 0.4 M at 90°C for 8 hours. The growth solution was then doped with 1% wt gallium nitrate hydrate. The grown ZnO nanostructures were characterized by X-Ray Diffraction (XRD), Field Emission Scanning Electron Microscopy (FESEM) and Energy Dispersive X-Ray (EDX) and UV-Vis Spectroscopy. The samples were crystalline with wurtzite-hexagonal and their crystal orientation was (100), (002), (101), and (110). The morphological shape of the samples changed with the concentration of the precursor. The optical absorption decreased as the concentration increased. As can be seen from SEM images that the diameter of the particles ranged from 95 to 500 nm and the thickness ranged from 1540 to 3640 nm (1.54-3.64 µm). The best performance of DSSC was obtained from the sample utilizing the ZnO nanostructures prepared at 0.1 M precursor, with their photovoltaic parameters were the Jsc of 2.190 mA cm-2, FF of 0.39, and η of 0.41%, respectively.

  8. Dye- and quantum dot-sensitized solar cells based on nanostructured wide-bandgap semiconductors via an integrated experimental and modeling study

    NASA Astrophysics Data System (ADS)

    Xin, Xukai

    Dye-sensitized solar cells (DSSCs) and quantum dot-sensitized solar cells (QDSSCs) are two promising alternative, cost-effective concepts for solar-to-electric energy conversion that have been offered to challenge conventional Si solar cells over the past decade. The configuration of a DSSC or a QDSSC consists of sintered TiO2 nanoparticle films, ruthenium-based dyes or quantum dots (QDs) (i.e., sensitizers), and electrolytes. Upon the absorption of photons, the dyes or QDs generate excitons (i.e., electron-hole pairs). Subsequently, the electrons inject into the TiO2 photoanode to generate photocurrent; scavenged by a redox couple, holes transport to the cathode. The overall power conversion efficiency (PCE) of a DSSC or QDSSC is dictated by the light harvest efficiency, quantum yield for charge injection, and charge collection efficiency at the electrodes. The goal of our research is to understand the fundamental physics and performance of DSSCs and QDSSCs with improved PCE at the low cost based on rational engineering of TiO2 nanostructures, sensitizers, and electrodes through an integrated experimental and modeling study. In this presentation, I will discuss three aspects that I have accomplished over the last several years. (1) Effects of surface treatment and structural modification of photoanode on the performance of DSSCs. First, our research indicates that the surface treatment with both TiCl4 and oxygen plasma yields the most efficient dye-sensitized TiO2-nanoparticle solar cells. A maximum PCE is achieved with a 21 microm thick TiO2 film; the PCE further increases to 8.35% after TiCl4 and O 2 plasma treatments, compared to the untreated TiO2 ( PCE = 3.86%). Second, we used a layer of TiO2 nanoparticle film coated on the FTO glass, and a bilayer of TiO2nanoparticle/freestanding TiO2 nanotube film deposited on the FTO glass as photoanodes. The J˜V parameter analysis acquired by equivalent circuit model simulation reveals that nanotubular structures are

  9. Feasibility of solar-pumped dye lasers

    NASA Technical Reports Server (NTRS)

    Lee, Ja H.; Kim, Kyung C.; Kim, Kyong H.

    1987-01-01

    Dye laser gains were measured at various pump-beam irradiances on a dye cell in order to evaluate the feasibility of solar pumping. Rhodamine 6G dye was considered as a candidate for the solar-pumped laser because of its high utilization of the solar spectrum and high quantum efficiency. Measurements show that a solar concentration of 20,000 is required to reach the threshold of the dye.

  10. Dye-sensitized solar cells

    DOEpatents

    Skotheim, T.A.

    1980-03-04

    A low-cost dye-sensitized Schottky barrier solar cell is comprised of a substrate of semiconductor with an ohmic contact on one face, a sensitizing dye adsorbed onto the opposite face of the semiconductor, a transparent thin-film layer of a reducing agent over the dye, and a thin-film layer of metal over the reducing agent. The ohmic contact and metal layer constitute electrodes for connection to an external circuit and one or the other or both are made transparent to permit light to penetrate to the dye and be absorbed therein for generating electric current. The semiconductor material chosen to be the substrate is one having a wide bandgap and which therefore is transparent; the dye selected is one having a ground state within the bandgap of the semiconductor to generate carriers in the semiconductor, and a first excited state above the conduction band edge of the semiconductor to readily conduct electrons from the dye to the semiconductor; the reducing agent selected is one having a ground state above the ground state of the sensitizer to provide a plentiful source of electrons to the dye during current generation and thereby enhance the generation; and the metal for the thin-film layer of metal is selected to have a Fermi level in the vicinity of or above the ground state of the reducing agent to thereby amply supply electrons to the reducing agent. 3 figs.

  11. Dye-sensitized solar cells

    DOEpatents

    Skotheim, Terje A. [Berkeley, CA

    1980-03-04

    A low-cost dye-sensitized Schottky barrier solar cell comprised of a substrate of semiconductor with an ohmic contact on one face, a sensitizing dye adsorbed onto the opposite face of the semiconductor, a transparent thin-film layer of a reducing agent over the dye, and a thin-film layer of metal over the reducing agent. The ohmic contact and metal layer constitute electrodes for connection to an external circuit and one or the other or both are made transparent to permit light to penetrate to the dye and be absorbed therein for generating electric current. The semiconductor material chosen to be the substrate is one having a wide bandgap and which therefore is transparent; the dye selected is one having a ground state within the bandgap of the semiconductor to generate carriers in the semiconductor, and a first excited state above the conduction band edge of the semiconductor to readily conduct electrons from the dye to the semiconductor; the reducing agent selected is one having a ground state above the ground state of the sensitizer to provide a plentiful source of electrons to the dye during current generation and thereby enhance the generation; and the metal for the thin-film layer of metal is selected to have a Fermi level in the vicinity of or above the ground state of the reducing agent to thereby amply supply electrons to the reducing agent.

  12. Sensitized solar cells based on nanostructures

    NASA Astrophysics Data System (ADS)

    Lu, Liyou

    Sensitized solar cells (SSCs) based on nanostructures including dye sensitized solar cells (DSSCs) and quantum dot sensitized solar cells (QDSSCs) have attracted great research interest due to their potential in converting sunlight into electricity and solving the energy problem. Metal oxide nanowires, as an important type of nanostructures were grown and applied in the SSCs. In this dissertation, two types of nanowires, ZnO and Zn2GeO4 nanowires were successfully grown onto fluorine-doped-tin-oxide (FTO) coated substrates using a chemical vapor deposition method. This method provides an important way to grow ZnO nanowires directly on FTO substrates without using any catalyst. ZnO nanowires with length of more than 30 mum were used as the photoanode for DSSCs. The dependence of solar cell performance on nanowire length and annealing temperature was studied. Zn2GeO4 nanowires were also directly synthesized on FTO substrates and were utilized as the photoanode in DSSCs and QDSSCs. Transient photocurrent and photovoltage decay measurements were conducted in the SSCs, which showed that the dye sensitization pH was important for DSSCs and that both the QDs coverage and band alignment between QDs and nanowires were key parameters for QDSSCs in order to have a good energy conversion efficiency.

  13. Dye-sensitized solar cells with natural dyes extracted from plant seeds

    NASA Astrophysics Data System (ADS)

    El-Ghamri, Hatem S.; El-Agez, Taher M.; Taya, Sofyan A.; Abdel-Latif, Monzir S.; Batniji, Amal Y.

    2014-12-01

    The application of natural dyes extracted from plant seeds in the fabrication of dye-sensitized solar cells (DSSCs) has been explored. Ten dyes were extracted from different plant seeds and used as sensitizers for DSSCs. The dyes were characterized using UV-Vis spectrophotometry. DSSCs were prepared using TiO2 and ZnO nanostructured mesoporous films. The highest conversion efficiency of 0.875 % was obtained with an allium cepa (onion) extract-sensitized TiO2 solar cell. The process of TiO2-film sintering was studied and it was found that the sintering procedure significantly affects the response of the cell. The short circuit current of the DSSC was found to be considerably enhanced when the TiO2 semiconducting layer was sintered gradually.

  14. Key Physical Mechanisms in Nanostructured Solar Cells

    SciTech Connect

    Dr Stephan Bremner

    2010-07-21

    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.

  15. Magnetron sputtering in the creation of photonic nanostructures derived from Sasakia Charonda Formosana-butterfly wings for applied in dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Niu, Haihong; Zhou, Ru; Cheng, Cong; Zhang, Gonghai; Hu, Yu; Huang, Bin; Zhang, Shouwei; Shang, Xin; Xia, Mei; Xu, Jinzhang

    2016-09-01

    Creating new functional materials derived from the structures seen on butterfly wings has achieved interest in a variety of research topics. However, there need a concision approach could result in a high-quality, precise, and convenient process for the fabrication of complex nanostructures replication with unique functionalities based on the butterfly wings. Here we developed a pithy approach based on a magnetron sputtering metal Ti process for biotemplating used to refine hierarchically porous titanium dioxide photonic crystal nanostructures (TiO2sbnd PCN), themselves derived from nanostructures present on the wings of Sasakia Charonda Formosana (S. Charonda) butterflies. For the first time, the TiO2sbnd PCN were deposited on the top of the P25 active layer and were used to fabricate DSSCs as the light-scattering layers of photoanodes with power conversion efficiencies of up to 8.7%. Remarkably, a much enhanced photocurrent density and a prominent photoelectrochemical conversion capability have been achieved, which are exceeding most of the previously reported photoanodes as well as a similar butterflies replication-based device structure. Our study suggests many exciting opportunities of developing artificially engineered butterfly wing-based solar-to-fuel conversion.

  16. Enhancing Solar Cell Efficiencies through 1-D Nanostructures

    PubMed Central

    2009-01-01

    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.

  17. Enhancement of Spectral Response of Dye-Sensitized Solar Cells

    NASA Astrophysics Data System (ADS)

    Chang, Shuai

    ruthenium-based/organic dyes for co-sensitized DSSCs are also investigated. Another approach is to increase light utility in DSSCs exploiting surface plasmon resonance (SPR) of noble metal nanostructures (e.g. Au, Ag). In this thesis, I will show that the strong longitudinal plasmonic absorption of Au nanorods (NRs) can be used to increase the low-photon energy sunlight harvesting in DSSCs, broadening strong light response of the devices. In specific, a remarkable improvement in photocurrent generation at 600-720 nm is achieved. This enhancement mechanism is anticipated to be applied to other kind of DSSCs with various dye molecules. In another approach, AuNRs/TiO2 core-shell nanostructures are employed as scattering layer for plasmon-enhanced light harvesting in DSSCs and also obtained positive results. Evolved from DSSCs, perovskite solar cells (PSCs) now become a new favorite in the field of photovoltaics. An intrinsic problem of this kind of solar cells is the use of lead based materials, which is of high toxicity and prohibited by the European Union and some other countries. I have conducted some fundamental research for lead-free PSCs using tin-based perovskite and have observed a surface plasmon resonance absorption of the organometal perovskite film of CH3NH3SnI3, which has potential applications for IR-absorption in the future solar photovoltaics. I believe the improved understanding on the co-sensitization mechanisms and the plasmonic effect to broaden the spectral response in DSSCs are luciferous for the design and fabrication of the new generation solar cells with high-efficiency and low-cost.

  18. Nanostructured Materials for Solar Cells

    NASA Technical Reports Server (NTRS)

    Bailey, Sheila; Raffaelle, Ryne; Castro, Stephanie; Fahey, S.; Gennett, T.; Tin, P.

    2003-01-01

    The use of both inorganic and organic nanostructured materials in producing high efficiency photovoltaics is discussed in this paper. Recent theoretical results indicate that dramatic improvements in device efficiency may be attainable through the use of semiconductor quantum dots in an ordinary p-i-n solar cell. In addition, it has also recently been demonstrated that quantum dots can also be used to improve conversion efficiencies in polymeric thin film solar cells. A similar improvement in these types of cells has also been observed by employing single wall carbon nanotubes. This relatively new carbon allotrope may assist both in the disassociation of excitons as well as carrier transport through the composite material. This paper reviews the efforts that are currently underway to produce and characterize these nanoscale materials and to exploit their unique properties.

  19. Plasmonic Nanostructures for Solar and Biological Application

    NASA Astrophysics Data System (ADS)

    Neumann, Oara

    The electromagnetic absorption properties of plasmonic nanostructures were utilized to develop mesoscopic sites for highly efficient photothermal generation steam, SERS biosensing, and light-triggered cellular delivery uptake. Plasmonic nanostructures embedded in common thermal solutions produces vapor without the requirement of heating the fluid volume. When particles are dispersed in water at ambient temperature, energy is directed primarily to vaporization of water into steam, with a much smaller fraction resulting in heating of the fluid. Solar illuminated aqueous nanoparticle solution can drive water-ethanol distillation, yielding fractions significantly richer in ethanol content than simple thermal distillation and also produced saturated steam destroying Geobacillus stearothermophilus bacteria in a compact solar powered autoclave. Subwavelength biosensing sites were developed using the plasmonic properties of gold nanoshells to investigate the properties of aptamer (DNA) target complexes. Nanoshells are tunable core-shell nanoparticles whose resonant absorption and scattering properties are dependent on core/shell thickness ratio. Nanoshells were used to develop a label free detection method using SERS to monitor conformational change induced by aptamer target binding. The conformational changes to the aptamers induced by target binding were probed by monitoring the aptamer SERS spectra reproducibility. Furthermore, nanoshells can serve as a nonviral light-controlled delivery vector for the precise temporal and spatial control of molecular delivery in vitro. The drug delivery concept using plasmonic vectors was shown using a monolayer of ds-DNA attached to the nanoshell surface and the small molecular "parcel" intercalated inside ds-DNA loops. DAPI, a fluorescent dye, was used as the molecular parcel to visualize the release process in living cells. Upon laser illumination at the absorption resonance the nanoshell converts photon energy into heat producing a

  20. Photoinduced translational molecular mobility in solid nanostructured azo dye films

    SciTech Connect

    Ezhov, A A; Kozenkov, V M; Magnitskii, Sergey A; Nagorskii, Nikolay M; Panov, Vladimir I

    2011-11-30

    A new mechanism controlling the molecular motion in thin azo-containing films during a photoinduced change in the surface nanorelief is found. It is shown experimentally that exposure of a solid AD-1 azo dye, deposited on a glass substrate, to incoherent linearly polarised light leads to formation of nanostructures with a characteristic size of 200 nm, which are similar to droplets of melt of this dye on the same substrate. It is shown that photoinduced mass transport in a solid AD-1 azo dye film can be explained by the mobility of molecules related to their trans-cis-photoisomerisation, which leads to film softening with subsequent formation of spherical protrusions under surface tension forces.

  1. Improving the dye-sensitized solar cell

    NASA Astrophysics Data System (ADS)

    Willig, Frank

    2007-09-01

    Two dye sensitized solar cells (DSC) can be joined to form a tandem cell with two separate absorption ranges for the two different absorber materials. This can enhance the solar conversion efficiency and in particular the photovoltage of the DSC. Water splitting appears as a realistic long term target. The DSC tandem can be realized as n-n junction employing known dye molecules with optimal absorption spectra. Dye molecules with elongated shapes can be realized by covalently attaching a conducting bridge group terminated by an anchor group to a desired chromophore. Due to the long conducting bridge group separating the hole state of the dye from the surface of the semiconductor recombination is slowed down. The ordered molecular structure can be self-assembled on the recently introduced rod or cylinder shaped oxide electrodes but will not slow down recombination in the nm-cavities of the conventional TiO II Graetzel electrode.

  2. Rapid dye adsorption via surface modification of TiO2 photoanodes for dye-sensitized solar cells.

    PubMed

    Kim, Boeun; Park, Se Woong; Kim, Jae-Yup; Yoo, Kicheon; Lee, Jin Ah; Lee, Min-Woo; Lee, Doh-Kwon; Kim, Jin Young; Kim, BongSoo; Kim, Honggon; Han, Sunghwan; Son, Hae Jung; Ko, Min Jae

    2013-06-12

    A facile method for increasing the reaction rate of dye adsorption, which is the most time-consuming step in the production of dye-sensitized solar cells (DSSCs), was developed. Treatment of a TiO2 photoanode with aqueous nitric acid solution (pH 1) remarkably reduced the reaction time required to anchor a carboxylate anion of the dye onto the TiO2 nanoparticle surface. After optimization of the reaction conditions, the dye adsorption process became 18 times faster than that of the conventional adsorption method. We studied the influence of the nitric acid treatment on the properties of TiO2 nanostructures, binding modes of the dye, and adsorption kinetics, and found that the reaction rate improved via the synergistic effects of the following: (1) electrostatic attraction between the positively charged TiO2 surface and ruthenium anion increases the collision frequency between the adsorbent and the anchoring group of the dye; (2) the weak anchoring affinity of NO3(-) in nitric acid with metal oxides enables the rapid coordination of an anionic dye with the metal oxide; and (3) sufficient acidity of the nitric acid solution effectively increases the positive charge density on the TiO2 surface without degrading or transforming the TiO2 nanostructure. These results demonstrate the developed method is effective for reducing the overall fabrication time without sacrificing the performance and long-term stability of DSSCs. PMID:23679678

  3. Dye-sensitized Schottky barrier solar cells

    DOEpatents

    Skotheim, Terje A.

    1978-01-01

    A low-cost dye-sensitized Schottky barrier solar cell comprised of a substrate of semiconductor with an ohmic contact on one face, a sensitizing dye adsorbed onto the opposite face of the semiconductor, a transparent thin-film layer of a reducing agent over the dye, and a thin-film layer of metal over the reducing agent. The ohmic contact and metal layer constitute electrodes for connection to an external circuit and one or the other or both are made transparent to permit light to penetrate to the dye and be absorbed therein for generating electric current. The semiconductor material chosen to be the substrate is one having a wide bandgap and which therefore is transparent; the dye selected is one having a ground state within the bandgap of the semiconductor to generate carriers in the semiconductor, and a first excited state above the conduction band edge of the semiconductor to readily conduct electrons from the dye to the semiconductor; the reducing agent selected is one having a ground state above the ground state of the sensitizer to provide a plentiful source of electrons to the dye during current generation and thereby enhance the generation; and the metal for the thin-film layer of metal is selected to have a Fermi level in the vicinity of or above the ground state of the reducing agent to thereby amply supply electrons to the reducing agent.

  4. Artificial evolution of coumarin dyes for dye sensitized solar cells.

    PubMed

    Venkatraman, Vishwesh; Abburu, Sailesh; Alsberg, Bjørn Kåre

    2015-11-01

    The design and discovery of novel molecular structures with optimal properties has been an ongoing effort for materials scientists. This field has in general been dominated by experiment driven trial-and-error approaches that are often expensive and time-consuming. Here, we investigate if a de novo computational design methodology can be applied to the design of coumarin-based dye sensitizers with improved properties for use in Grätzel solar cells. To address the issue of synthetic accessibility of the designed compounds, a fragment-based assembly is employed, wherein the combination of chemical motifs (derived from the existing databases of structures) is carried out with respect to user-adaptable set of rules. Rather than using computationally intensive density functional theory (DFT)/ab initio methods to screen candidate dyes, we employ quantitative structure-property relationship (QSPR) models (calibrated from empirical data) for rapid estimation of the property of interest, which in this case is the product of short circuit current (Jsc) and open circuit voltage (Voc). Since QSPR models have limited validity, pre-determined applicability domain criteria are used to prevent unacceptable extrapolation. DFT analysis of the top-ranked structures provides supporting evidence of their potential for dye sensitized solar cell applications. PMID:26428071

  5. Stretchable, wearable dye-sensitized solar cells.

    PubMed

    Yang, Zhibin; Deng, Jue; Sun, Xuemei; Li, Houpu; Peng, Huisheng

    2014-05-01

    A stretchable, wearable dye-sensitized solar-cell textile is developed from elastic, electrically conducting fiber as a counter electrode and spring-like titanium wire as the working electrode. Dyesensitized solar cells are demonstrated with energy-conversion efficiencies up to 7.13%. The high energy-conversion efficiencies can be well maintained under stretch by 30% and after stretch for 20 cycles. PMID:24648169

  6. Titania nanobundle networks as dye-sensitized solar cell photoanodes

    NASA Astrophysics Data System (ADS)

    Dong, Cunku; Xiang, Wanchun; Huang, Fuzhi; Fu, Dongchuan; Huang, Wenchao; Bach, Udo; Cheng, Yi-Bing; Li, Xin; Spiccia, Leone

    2014-03-01

    Quasi-one-dimensional (1D) titania nanobundles were synthesized via a hydrothermal method and used to print random network nanostructured films. These films are shown to be ideally suited for application as photoanodes in dye-sensitized solar cells (DSCs) as they have a higher porosity compared to the traditional 1D nanostructured TiO2 materials. Devices constructed using the N719 dye and iodide/triiodide as the redox mediator in the electrolyte yielded energy conversion efficiencies (η = 6.1 +/- 0.2%), which were marginally lower than for devices made with the commonly used P25 titania films (η = 6.3 +/- 0.1%) under one sun simulated solar radiation. Application of an electrolyte based on the [Co(bpy)3]2+/3+ redox couple and the MK2 organic sensitizer resulted in higher efficiencies (η = 7.70 +/- 0.1%) than for the P25 devices (η = 6.3 +/- 0.3%). Each performance parameter (short circuit current density, open circuit voltage and fill factor) was higher for the TiO2 nanobundle devices than those for the P25-based devices. The results of electrochemical impedance spectroscopy (EIS), intensity-modulated photovoltage spectroscopy (IMVS), and dye-loading measurements indicated that the better performance of TiO2 nanobundle devices with cobalt electrolytes correlates with higher porosity, relatively fast electron transport and more efficient suppression of electron recombination. A faster rate of diffusion of the cobalt complexes through the highly porous TiO2 nanobundle network is proposed to contribute to the enhanced device efficiency.Quasi-one-dimensional (1D) titania nanobundles were synthesized via a hydrothermal method and used to print random network nanostructured films. These films are shown to be ideally suited for application as photoanodes in dye-sensitized solar cells (DSCs) as they have a higher porosity compared to the traditional 1D nanostructured TiO2 materials. Devices constructed using the N719 dye and iodide/triiodide as the redox mediator in

  7. Titanium dioxide nanostructure synthesized by sol-gel for organic solar cells using natural dyes extracted from black and red sticky rice

    NASA Astrophysics Data System (ADS)

    Ramelan, A. H.; Harjana, H.; Sakti, L. S.

    2012-06-01

    Nanocrystalline semiconductor metal oxides have achieved a great importance in our industrial world today. They may be defined as metal oxides with crystal size between 1 and 100 nm. TiO2 nanosize particles have attracted significant interest of materials scientists and physicists due to their special properties and have attained a great importance in several technological applications such as photocatalysis, sensors, solar cells and memory devices. TiO2 nanoparticles can be produced by a variety of techniques ranging from simple chemical to mechanical to vacuum methods, including many variants of physical and chemical vapour deposition techniques. In the present research work we report the synthesis of TiO2 nanoparticles by Sol-Gel technique. The characterization of particles was carried out by XRD and XRF techniques. The importance and applications of these nanoparticles for solar cells are also discussed in this work.

  8. Metal-free organic dyes for TiO2 and ZnO dye-sensitized solar cells.

    PubMed

    Selopal, Gurpreet Singh; Wu, Hui-Ping; Lu, Jianfeng; Chang, Yu-Cheng; Wang, Mingkui; Vomiero, Alberto; Concina, Isabella; Diau, Eric Wei-Guang

    2016-01-01

    We report the synthesis and characterization of new metal-free organic dyes (namely B18, BTD-R, and CPTD-R) which designed with D-π-A concept to extending the light absorption region by strong conjugation group of π-linker part and applied as light harvester in dye sensitized solar cells (DSSCs). We compared the photovoltaic performance of these dyes in two different photoanodes: a standard TiO2 mesoporous photoanode and a ZnO photoanode composed of hierarchically assembled nanostructures. The results demonstrated that B18 dye has better photovoltaic properties compared to other two dyes (BTD-R and CPTD-R) and each dye has higher current density (Jsc) when applied to hierarchical ZnO nanocrystallites than the standard TiO2 mesoporous film. Transient photocurrent and photovoltage decay measurements (TCD/TVD) were applied to systematically study the charge transport and recombination kinetics in these devices, showing the electron life time (τR) of B18 dye in ZnO and TiO2 based DSSCs is higher than CPTD-R and BTD-R based DSSCs, which is consistent with the photovoltaic performances. The conversion efficiency in ZnO based DSSCs can be further boosted by 35%, when a compact ZnO blocking layer (BL) is applied to inhibit electron back reaction. PMID:26738698

  9. Metal-free organic dyes for TiO2 and ZnO dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Selopal, Gurpreet Singh; Wu, Hui-Ping; Lu, Jianfeng; Chang, Yu-Cheng; Wang, Mingkui; Vomiero, Alberto; Concina, Isabella; Diau, Eric Wei-Guang

    2016-01-01

    We report the synthesis and characterization of new metal-free organic dyes (namely B18, BTD-R, and CPTD-R) which designed with D-π-A concept to extending the light absorption region by strong conjugation group of π-linker part and applied as light harvester in dye sensitized solar cells (DSSCs). We compared the photovoltaic performance of these dyes in two different photoanodes: a standard TiO2 mesoporous photoanode and a ZnO photoanode composed of hierarchically assembled nanostructures. The results demonstrated that B18 dye has better photovoltaic properties compared to other two dyes (BTD-R and CPTD-R) and each dye has higher current density (Jsc) when applied to hierarchical ZnO nanocrystallites than the standard TiO2 mesoporous film. Transient photocurrent and photovoltage decay measurements (TCD/TVD) were applied to systematically study the charge transport and recombination kinetics in these devices, showing the electron life time (τR) of B18 dye in ZnO and TiO2 based DSSCs is higher than CPTD-R and BTD-R based DSSCs, which is consistent with the photovoltaic performances. The conversion efficiency in ZnO based DSSCs can be further boosted by 35%, when a compact ZnO blocking layer (BL) is applied to inhibit electron back reaction.

  10. Metal-free organic dyes for TiO2 and ZnO dye-sensitized solar cells

    PubMed Central

    Selopal, Gurpreet Singh; Wu, Hui-Ping; Lu, Jianfeng; Chang, Yu-Cheng; Wang, Mingkui; Vomiero, Alberto; Concina, Isabella; Diau, Eric Wei-Guang

    2016-01-01

    We report the synthesis and characterization of new metal-free organic dyes (namely B18, BTD-R, and CPTD-R) which designed with D-π-A concept to extending the light absorption region by strong conjugation group of π-linker part and applied as light harvester in dye sensitized solar cells (DSSCs). We compared the photovoltaic performance of these dyes in two different photoanodes: a standard TiO2 mesoporous photoanode and a ZnO photoanode composed of hierarchically assembled nanostructures. The results demonstrated that B18 dye has better photovoltaic properties compared to other two dyes (BTD-R and CPTD-R) and each dye has higher current density (Jsc) when applied to hierarchical ZnO nanocrystallites than the standard TiO2 mesoporous film. Transient photocurrent and photovoltage decay measurements (TCD/TVD) were applied to systematically study the charge transport and recombination kinetics in these devices, showing the electron life time (τR) of B18 dye in ZnO and TiO2 based DSSCs is higher than CPTD-R and BTD-R based DSSCs, which is consistent with the photovoltaic performances. The conversion efficiency in ZnO based DSSCs can be further boosted by 35%, when a compact ZnO blocking layer (BL) is applied to inhibit electron back reaction. PMID:26738698

  11. Improving optical absorptivity of natural dyes for fabrication of efficient dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Hemmatzadeh, Reza; Mohammadi, Ahmad

    2013-11-01

    Efficient and cheap dye-sensitized solar cells (DSSCs) were fabricated using natural dyes from Pastinaca sativa and Beta vulgaris. Natural dyes are environmentally and economically superior to ruthenium-based dyes because they are nontoxic and cheap. However, the conversion efficiency of dye-sensitized solar cells based on natural dyes is low. One way to improve the DSSC performance is to enhance the absorptivity of extracted dyes. We investigated the influence of various factors in the extraction process, such as utilization of different extraction approaches, the acidity of extraction solvent, and different compounds of solvents on the optical absorption spectra. It was found that we could considerably enhance the optical absorptivity of dye and consequently the performance of DSSC by choosing a proper mixture of ethanol and water for extracting solvent and also the acidity of dye solution.

  12. Effects of pH of Dyes on Characteristics of Dye-Sensitized Solar Cells

    NASA Astrophysics Data System (ADS)

    Furukawa, Shoji; Iino, Hiroshi; Kukita, Koudai; Kaminosono, Kaoru

    Dye-sensitized solar cells were fabricated using natural dyes and synthesized dyes in which rear metal was not contained. Effects of pH of dyes on the characteristics of the dye-sensitized solar cells were also examined. As a result, it was found that the conversion efficiency of the dye-sensitized solar cell fabricated using red-cabbage dye with a pH of 2.5 was 0.10 point larger than that of the solar cell fabricated using red-cabbage dye with a pH of 4.0. It was also found that the conversion efficiency of the solar cell fabricated using red-perilla dye with a pH of 3.1 was 0.10 point larger than that of the solar cell fabricated using red-perilla dye with a pH of 5.8. The results are discussed on the bases of the molecular structure of mainly contained dye and the optical absorption spectra.

  13. Threshold pump power of a solar-pumped dye laser

    NASA Technical Reports Server (NTRS)

    Lee, Ja H.; Kim, Kyung C.; Kim, Kyong H.

    1988-01-01

    Threshold solar power for dye laser pumping has been determined by measuring the gain of a rhodamine 6G dye laser amplifier at various solar-simulated irradiances on an amplifier cell. The measured threshold was 20,000 solar constants (2.7 kW/sq cm) for the dye volume of 2 x 5 x 40 cu mm and the optimum dye concentration of 0.001 M. The threshold is about one-third of that achievable with a high-intensity solar concentrator.

  14. On the early development of organic dyes for dye-sensitized solar cells.

    PubMed

    Kloo, Lars

    2013-07-28

    This viewpoint describes the background of the development of organic dyes for dye-sensitized solar cells, the impact of the 2006 ChemComm paper by Sun, Hagfeldt and co-workers regarding the D5 D-π-A-family of dyes, some recent developments and possible future challenges to meet. PMID:23775237

  15. Elongated nanostructures for radial junction solar cells.

    PubMed

    Kuang, Yinghuan; Vece, Marcel Di; Rath, Jatindra K; Dijk, Lourens van; Schropp, Ruud E I

    2013-10-01

    In solar cell technology, the current trend is to thin down the active absorber layer. The main advantage of a thinner absorber is primarily the reduced consumption of material and energy during production. For thin film silicon (Si) technology, thinning down the absorber layer is of particular interest since both the device throughput of vacuum deposition systems and the stability of the devices are significantly enhanced. These features lead to lower cost per installed watt peak for solar cells, provided that the (stabilized) efficiency is the same as for thicker devices. However, merely thinning down inevitably leads to a reduced light absorption. Therefore, advanced light trapping schemes are crucial to increase the light path length. The use of elongated nanostructures is a promising method for advanced light trapping. The enhanced optical performance originates from orthogonalization of the light's travel path with respect to the direction of carrier collection due to the radial junction, an improved anti-reflection effect thanks to the three-dimensional geometric configuration and the multiple scattering between individual nanostructures. These advantages potentially allow for high efficiency at a significantly reduced quantity and even at a reduced material quality, of the semiconductor material. In this article, several types of elongated nanostructures with the high potential to improve the device performance are reviewed. First, we briefly introduce the conventional solar cells with emphasis on thin film technology, following the most commonly used fabrication techniques for creating nanostructures with a high aspect ratio. Subsequently, several representative applications of elongated nanostructures, such as Si nanowires in realistic photovoltaic (PV) devices, are reviewed. Finally, the scientific challenges and an outlook for nanostructured PV devices are presented. PMID:24088584

  16. Investigating dye-sensitised solar cells

    NASA Astrophysics Data System (ADS)

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

    2010-05-01

    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.

  17. In-Situ Spectroscopic Analyses of the Dye Uptake on ZnO and TiO2 Photoanodes for Dye-Sensitized Solar Cells.

    PubMed

    Shahzad, Nadia; Pugliese, Diego; Shahzad, Muhammad Imran; Tresso, Elena

    2015-08-01

    UV-Vis spectroscopic measurements have been performed on Dye-Sensitized Solar Cell (DSSC) photoanodes at different dye impregnation times ranging from few minutes to 24 hours. In addition to the traditional absorbance experiments, based on diffuse and specular reflectance of dye impregnated thin films and on the desorption of dye molecules from the photoanodes by means of a basic solution, an alternative in-situ solution depletion measurement, which enables fast and continuous evaluation of dye uptake, has been employed. Two different nanostructured semiconducting oxide films (mesoporous TiO2 and sponge-like ZnO) and two different dyes, the traditional Ruthenizer 535-bisTBA (N719) and a newly introduced metal-free organic dye based on a hemi-squaraine molecule (CT1), have been analyzed. DSSCs have been fabricated with the dye-impregnated photoanodes using a customized microfluidic architecture. The dye adsorption results are discussed and correlated to the obtained DSSC electrical performances such as photovoltaic conversion efficiencies and Incident Photon-to-electron Conversion Efficiency (IPCE) spectra. It is shown that simple UV-Vis measurements can give useful insights on the dye adsorption mechanisms and on the evaluation of the optimal impregnation times. PMID:26369186

  18. Nanowire dye-sensitized solar cells.

    PubMed

    Law, Matt; Greene, Lori E; Johnson, Justin C; Saykally, Richard; Yang, Peidong

    2005-06-01

    Excitonic solar cells-including organic, hybrid organic-inorganic and dye-sensitized cells (DSCs)-are promising devices for inexpensive, large-scale solar energy conversion. The DSC is currently the most efficient and stable excitonic photocell. Central to this device is a thick nanoparticle film that provides a large surface area for the adsorption of light-harvesting molecules. However, nanoparticle DSCs rely on trap-limited diffusion for electron transport, a slow mechanism that can limit device efficiency, especially at longer wavelengths. Here we introduce a version of the dye-sensitized cell in which the traditional nanoparticle film is replaced by a dense array of oriented, crystalline ZnO nanowires. The nanowire anode is synthesized by mild aqueous chemistry and features a surface area up to one-fifth as large as a nanoparticle cell. The direct electrical pathways provided by the nanowires ensure the rapid collection of carriers generated throughout the device, and a full Sun efficiency of 1.5% is demonstrated, limited primarily by the surface area of the nanowire array. PMID:15895100

  19. Photostability of low cost dye-sensitized solar cells based on natural and synthetic dyes

    NASA Astrophysics Data System (ADS)

    Abdou, E. M.; Hafez, H. S.; Bakir, E.; Abdel-Mottaleb, M. S. A.

    2013-11-01

    This paper deals with the use of some natural pigments as well as synthetic dyes to act as sensitizers in dye-sensitized solar cells (DSSCs). Anthocyanin dye extracted from rosella (Hibiscus sabdariffa L.) flowers, the commercially available textile dye Remazole Red RB-133 (RR) and merocyanin-like dye based on 7-methyl coumarin are tested. The photostability of the three dyes is investigated under UV-Vis light exposure. The results show a relatively high stability of the three dyes. Moreover, the photostability of the solid dyes is studied over the TiO2 film electrodes. A very low decolorization rates are recorded as; rate constants k = 1.6, 2.1 and 1.9 × 10-3 min-1 for anthocyanin, RR and coumarin dyes, respectively. The stability results favor selecting anthocyanin as a promising sensitizer candidate in DSSCs based on natural products. Dyes-sensitized solar cells are fabricated and their conversion efficiency (η) is 0.27%, 0.14% and 0.001% for the anthocyanin, RR and coumarin dyes, respectively. Moreover, stability tests of the sealed cells based on anthocyanin and RR dyes are done under continuous light exposure of 100 mW cm-2, reveals highly stable DSSCs.

  20. Photostability of low cost dye-sensitized solar cells based on natural and synthetic dyes.

    PubMed

    Abdou, E M; Hafez, H S; Bakir, E; Abdel-Mottaleb, M S A

    2013-11-01

    This paper deals with the use of some natural pigments as well as synthetic dyes to act as sensitizers in dye-sensitized solar cells (DSSCs). Anthocyanin dye extracted from rosella (Hibiscus sabdariffa L.) flowers, the commercially available textile dye Remazole Red RB-133 (RR) and merocyanin-like dye based on 7-methyl coumarin are tested. The photostability of the three dyes is investigated under UV-Vis light exposure. The results show a relatively high stability of the three dyes. Moreover, the photostability of the solid dyes is studied over the TiO2 film electrodes. A very low decolorization rates are recorded as; rate constants k=1.6, 2.1 and 1.9×10(-3)min(-1) for anthocyanin, RR and coumarin dyes, respectively. The stability results favor selecting anthocyanin as a promising sensitizer candidate in DSSCs based on natural products. Dyes-sensitized solar cells are fabricated and their conversion efficiency (η) is 0.27%, 0.14% and 0.001% for the anthocyanin, RR and coumarin dyes, respectively. Moreover, stability tests of the sealed cells based on anthocyanin and RR dyes are done under continuous light exposure of 100mWcm(-2), reveals highly stable DSSCs. PMID:23832227

  1. Theoretical evidence of multiple dye regeneration mechanisms in dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Liu, Tao; Troisi, Alessandro

    2013-05-01

    The multiple regeneration mechanisms in dye-sensitized solar cells (DSSC), with N3 (Ru(dcbpy)2(NCS)2) as dye and I-/I3- as redox shuttle, have been studied by DFT methods. Our results show that different reaction pathways are possible within the same dye and the actual mechanism is controlled by the initial geometry of the dyeI complex. By considering the rapid interconversion between different N3I geometries, the reaction mechanism where N3I dissociates into neutral dye and Irad radical is preferred to the mechanism where N3I reacts with a second iodide.

  2. Solar thermophotovoltaic system using nanostructures.

    PubMed

    Ungaro, Craig; Gray, Stephen K; Gupta, Mool C

    2015-09-21

    This paper presents results on a highly efficient experimental solar thermophotovoltaic (STPV) system using simulated solar energy. An overall power conversion efficiency of 6.2% was recorded under solar simulation. This was matched with a thermodynamic model, and the losses within the system, as well as a path forward to mitigate these losses, have been investigated. The system consists of a planar, tungsten absorbing/emitting structure with an anti-reflection layer coated laser-microtextured absorbing surface and single-layer dielectric coated emitting surface. A GaSb PV cell was used to capture the emitted radiation and convert it into electrical energy. This simple structure is both easy to fabricate and temperature stable, and contains no moving parts or heat exchange fluids. PMID:26406745

  3. Amorphous Silicon-Carbon Nanostructure Solar Cells

    NASA Astrophysics Data System (ADS)

    Schriver, Maria; Regan, Will; Loster, Matthias; Zettl, Alex

    2011-03-01

    Taking advantage of the ability to fabricate large area graphene and carbon nanotube networks (buckypaper), we produce Schottky junction solar cells using undoped hydrogenated amorphous silicon thin films and nanostructured carbon films. These films are useful as solar cell materials due their combination of optical transparency and conductance. In our cells, they behave both as a transparent conductor and as an active charge separating layer. We demonstrate a reliable photovoltaic effect in these devices with a high open circuit voltage of 390mV in buckypaper devices. We investigate the unique interface properties which result in an unusual J-V curve shape and optimize fabrication processes for improved solar conversion efficiency. These devices hold promise as a scalable solar cell made from earth abundant materials and without toxic and expensive doping processes.

  4. Dye-sensitized solar cells based on purple corn sensitizers

    NASA Astrophysics Data System (ADS)

    Phinjaturus, Kawin; Maiaugree, Wasan; Suriharn, Bhalang; Pimanpaeng, Samuk; Amornkitbamrung, Vittaya; Swatsitang, Ekaphan

    2016-09-01

    Natural dye extracted from husk, cob and silk of purple corn, were used for the first time as photosensitizers in dye sensitized solar cells (DSSCs). The dye sensitized solar cells fabrication process has been optimized in terms of solvent extraction. The resulting maximal efficiency of 1.06% was obtained from purple corn husk extracted by acetone. The ultraviolet-visible (UV-vis) spectroscopy, Fourier transform infrared spectroscopy (FTIR), electrochemical impedance spectroscopy (EIS) and incident photon-to-current efficiency (IPCE) were employed to characterize the natural dye and the DSSCs.

  5. Efficient Cosensitization Strategy for Dye-Sensitized Solar Cells

    NASA Astrophysics Data System (ADS)

    Colonna, Daniele; Capogna, Vincenzo; Lembo, Angelo; Brown, Thomas M.; Reale, Andrea; Di Carlo, Aldo

    2012-02-01

    The challenge of increasing the photocurrent of a dye solar cell device by acting on the spectral response is approached herein. Cosensitization of nanocrystalline titania photoanodes by using two complementary dyes is investigated considering the dyeing time as an additional parameter for the optimization of the cosensitization process. We find that the characteristics of the cosensitized cell can outperform those of the cells made with each single dye. This effect is related to the reduction of the molecular stacking of one of the dyes, which quenches electron transfer to TiO2. Cosensitization results are also related to the cell transparency.

  6. Efficiency enhancement in solid state dye sensitized solar cells by including inverse opals with controlled layer thicknesses

    NASA Astrophysics Data System (ADS)

    Zheng, Hanbin; Shah, Said Karim; Abbas, Mamatimin; Ly, Isabelle; Rivera, Thomas; Almeida, Rui M.; Hirsch, Lionel; Toupance, Thierry; Ravaine, Serge

    2016-09-01

    The photoconversion efficiency of dye sensitized solar cells can be enhanced by the incorporation of light management nanostructures such as photonic crystals. Here, we present a facile route to incorporate titania inverse opals into solid state dye sensitized solar cells and report photoconversion efficiency enhancements of up to 56% compared with a model system without the inverse opal. Our approach is based on the precise design of titania inverse opals with a predetermined thickness that can be controlled at the individual layer level. By choosing an inverse opal exhibiting a photonic bandgap which overlaps the absorption bands of the dye, our results show that there is an optimal thickness of the inverse opal structure for maximum efficiency enhancement of the cell. This is the first experimental proof that the thickness of a titania inverse opal plays a pivotal role in cell efficiency enhancement in solid state dye sensitized solar cells.

  7. Nano-TiO2 for dye-sensitized solar cells.

    PubMed

    Baraton, Marie-Isabelle

    2012-01-01

    Photovoltaics are amongst the most popular renewable energy sources and low-cost solar cell technologies are making progress to the market. Research on dye-sensitized solar cells (DSSCs) usually based on nanocrystalline TiO2 has been extensively pursued, and the number of papers and patents published in this area has grown exponentially over the last ten years. Research efforts have largely focused on the optimization of the dye, but recently the TiO2 nanocrystalline electrode itself has attracted more attention. It has been shown that particle size and shape, crystallinity, surface morphology and chemistry of the TiO2 material are key parameters to be controlled for optimized performance of the solar cell. This article will review the most recent research activities on nanostructured TiO2 for improvement of the DSSC performance. PMID:22023080

  8. Nanostructured refractory thin films for solar applications

    NASA Astrophysics Data System (ADS)

    Ollier, E.; Dunoyer, N.; Dellea, O.; Szambolics, H.

    2014-08-01

    Selective solar absorbers are key elements of all solar thermal systems. Solar thermal panels and Concentrated Solar Power (CSP) systems aim respectively at producing heat and electricity. In both cases, a surface receives the solar radiation and is designed to have the highest optical absorption (lowest optical reflectivity) of the solar radiation in the visible wavelength range where the solar intensity is the highest. It also has a low emissivity in the infrared (IR) range in order to avoid radiative thermal losses. Current solutions in the state of the art usually consist in deposited interferential thin films or in cermets [1]. Structured surfaces have been proposed and have been simulated because they are supposed to be more efficient when the solar radiation is not normal to the receiving surface and because they could potentially be fabricated with refractory materials able to sustain high operating temperatures. This work presents a new method to fabricate micro/nanostructured surfaces on molybdenum (refractory metal with a melting temperature of 2623°C). This method now allows obtaining a refractory selective surface with an excellent optical selectivity and a very high absorption in the visible range. This high absorption performance was obtained by achieving a double structuration at micro and nano scales thanks to an innovative process flow.

  9. A critical review of recent developments in nanomaterials for photoelectrodes in dye sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Raj, C. Clement; Prasanth, R.

    2016-06-01

    In a dye sensitized solar cell the photoanode performs a dual role of acting as a matrix for dye adsorption and as a charge transport medium for electron transport. The surface area and the electronic property of the material determine the current output of the device. So the performance of dye sensitized solar cell is significantly affected by our choice of material to be used as photoanode. High surface area, optimum carrier density, low impedance and efficient carrier transport are requirements for an efficient photoanode material in a DSSC. The goal of this review article is to highlight the fabrication methods used for the preparation of efficient nanostructured photoanodes. The application of these nanostructured photoanode materials and their impact on the device efficiency has been described in detail. The enhancement in the surface area of the material and its impact on the dye adsorption and current generation has been discussed. A detailed analysis of the role of different blocking layers used in improving the open circuit voltage of the device has been done. The outlook and future directions in improving the device performance are also discussed.

  10. ZnO disk-like structures and their application in dye sensitized solar cell

    NASA Astrophysics Data System (ADS)

    Wang, J. X.; Yang, Y.; Sun, X. W.

    2016-08-01

    Hexagonal ZnO nanodisks, nanorings and porous nanodisks were synthesized by a simple hydrothermal method. The morphologies, structure and their optical properties of the various ZnO disk-like structures were characterized and their growth mechanism was investigated. The prepared ZnO disk-like nanostructures were used in the fabrication of the dye-sensitized solar cells. Improved photovoltaic properties were achieved for the porous disk solar cells due to their special geometry enabled better light harvesting and reduced recombination.

  11. Assessment of dye distribution in sensitized solar cells by microprobe techniques

    NASA Astrophysics Data System (ADS)

    Barreiros, M. A.; Corregidor, V.; Alves, L. C.; Guimarães, F.; Mascarenhas, J.; Torres, E.; Brites, M. J.

    2015-04-01

    Dye sensitized solar cells (DSCs) have received considerable attention once this technology offers economic and environmental advantages over conventional photovoltaic (PV) devices. The PV performance of a DSC relies on the characteristics of its photoanode, which typically consists of a nanocrystalline porous TiO2 film, enabled with a large adsorptive surface area. Dye molecules that capture photons from light during device operation are attached to the film nanoparticles. The effective loading of the dye in the TiO2 electrode is of paramount relevance for controlling and optimizing solar cell parameters. Relatively few methods are known today for quantitative evaluation of the total dye adsorbed on the film. In this context, microprobe techniques come out as suitable tools to evaluate the dye surface distribution and depth profile in sensitized films. Electron Probe Microanalysis (EPMA) and Ion Beam Analytical (IBA) techniques using a micro-ion beam were used to quantify and to study the distribution of the Ru organometallic dye in TiO2 films, making use of the different penetration depth and beam sizes of each technique. Different 1D nanostructured TiO2 films were prepared, morphologically characterized by SEM, sensitized and analyzed by the referred techniques. Dye load evaluation in different TiO2 films by three different techniques (PIXE, RBS and EPMA/WDS) provided similar results of Ru/Ti mass fraction ratio. Moreover, it was possible to assess dye surface distribution and its depth profile, by means of Ru signal, and to visualize the dye distribution in sample cross-section through X-ray mapping by EPMA/EDS. PIXE maps of Ru and Ti indicated an homogeneous surface distribution. The assessment of Ru depth profile by RBS showed that some films have homogeneous Ru depth distribution while others present different Ru concentration in the top layer (2 μm thickness). These results are consistent with the EPMA/EDS maps obtained.

  12. Stability and efficiency of dye-sensitized solar cells based on papaya-leaf dye

    NASA Astrophysics Data System (ADS)

    Suyitno, Suyitno; Saputra, Trisma Jaya; Supriyanto, Agus; Arifin, Zainal

    2015-09-01

    The present article reports on the enhancement of the performance and stability of natural dye-based dye-sensitized solar cells (DSSCs). Natural dyes extracted from papaya leaves (PL) were investigated as sensitizers in TiO2-based DSSCs and evaluated in comparison with N719 dye. The acidity of the papaya-leaf extract dyes was tuned by adding benzoic acid. The TiO2 film-coated fluorine-doped tin oxide glass substrates were prepared using the doctor-blade method, followed by sintering at 450 °C. The counter electrode was coated by chemically deposited catalytic platinum. The working electrodes were immersed in N719 dye and papaya dye solutions with concentrations of 8 g/100 mL. The absorbance spectra of the dyes were obtained by ultra-violet-visible spectroscopy. The energy levels of the dyes were measured by the method of cyclic voltammetry. In addition, Fourier transform infrared spectroscopy was used to determine the characteristic functionalities of the dye molecules. The DSSC based on the N719 dye displayed a highest efficiency of 0.87% whereas those based on papaya-leaf dye achieved 0.28% at pH 3.5. The observed improved efficiency of the latter was attributed to the increased current density value. Furthermore, the DSSCs based on papaya-leaf dye with pH 3.5-4 exhibited better stability than those based on N719 dye. However, further studies are required to improve the current density and stability of natural dye-based DSSCs, including the investigation of alternative dye extraction routes, such as isolating the pure chlorophyll from papaya leaves and stabilizing it.

  13. Stability and efficiency of dye-sensitized solar cells based on papaya-leaf dye.

    PubMed

    Suyitno, Suyitno; Saputra, Trisma Jaya; Supriyanto, Agus; Arifin, Zainal

    2015-09-01

    The present article reports on the enhancement of the performance and stability of natural dye-based dye-sensitized solar cells (DSSCs). Natural dyes extracted from papaya leaves (PL) were investigated as sensitizers in TiO2-based DSSCs and evaluated in comparison with N719 dye. The acidity of the papaya-leaf extract dyes was tuned by adding benzoic acid. The TiO2 film-coated fluorine-doped tin oxide glass substrates were prepared using the doctor-blade method, followed by sintering at 450 °C. The counter electrode was coated by chemically deposited catalytic platinum. The working electrodes were immersed in N719 dye and papaya dye solutions with concentrations of 8 g/100 mL. The absorbance spectra of the dyes were obtained by ultra-violet-visible spectroscopy. The energy levels of the dyes were measured by the method of cyclic voltammetry. In addition, Fourier transform infrared spectroscopy was used to determine the characteristic functionalities of the dye molecules. The DSSC based on the N719 dye displayed a highest efficiency of 0.87% whereas those based on papaya-leaf dye achieved 0.28% at pH 3.5. The observed improved efficiency of the latter was attributed to the increased current density value. Furthermore, the DSSCs based on papaya-leaf dye with pH 3.5-4 exhibited better stability than those based on N719 dye. However, further studies are required to improve the current density and stability of natural dye-based DSSCs, including the investigation of alternative dye extraction routes, such as isolating the pure chlorophyll from papaya leaves and stabilizing it. PMID:25875031

  14. Computational study of diketopyrrolopyrrole-based organic dyes for dye sensitized solar cell applications.

    PubMed

    Fan, Wenjie; Tan, Dazhi; Zhang, Qijian; Wang, Huaxing

    2015-04-01

    Four diketopyrrolopyrrole (DPP)-based organic dyes utilizing the donor-π-acceptor motif were investigated by density functional theory (DFT) and time-dependent DFT (TDDFT) approaches. The four dyes were composed of different donor groups, i.e. indoline, carbazole, triphenylamine, and coumarin. We investigated the effects of the DPP unit and different donors on the spectra and electrochemical properties of the dyes, respectively. In comparison with the model dye which adopts a phenylene unit as the π-spacer, the DPP dyes all display remarkably enhanced spectral responses in the visible region of the solar spectrum. The key to this increase was the incorporation of electron-deficient DPP moieties to the molecular core, which significantly lowers LUMO levels and therefore reduces the band gap. The dye/(TiO2)46 anatase nanoparticle systems were also simulated to show the electronic structures at the interface. We studied some key properties including absorption spectra, light-harvesting efficiency, molecular orbital distributions, and injection time of electrons from the excited state of dye to the conduction band of TiO2. The dye DPP-I with indoline moiety as the electron donor demonstrates desirable energetic, electronic, and spectroscopic parameters for dye sensitized solar cells (DSSCs) applications. Our theoretical study is expected to provide valuable insights into the molecular design of novel DPP-based organic dyes for the optimizations of DSSCs. PMID:25662565

  15. Designing nanostructured one-dimensional TiO2 nanotube and TiO2 nanoparticle multilayer composite film as photoanode in dye-sensitized solar cells to increase the charge collection efficiency

    NASA Astrophysics Data System (ADS)

    Akilavasan, Jeganathan; Al-Jassim, Maufick; Bandara, Jayasundera

    2015-01-01

    A photoanode consisting of hydrothermally synthesized TiO2 nanotubes (TNT) and TiO2 nanoparticles (TNP) was designed for efficient charge collection in dye-sensitized solar cells. TNT and TNP films were fabricated on a conductive glass substrate by using electrophoretic deposition and doctor-blade methods, respectively. The TNP, TNT, and TNT/TNP bi-layer electrodes exhibit solar cell efficiencies of 5.3, 7.4, and 9.2%, respectively. Solar cell performance results indicate a higher short-circuit current density (Jsc) for the TNT/TNP bi-layer electrode when compared to a TNT or TNP electrode alone. The open-circuit voltages (Voc) of TNT/TNP and TNT electrodes are comparable while the Voc of TNP electrode is inferior to that of the TNT/TNP electrode. Fill factors of TNT/TNP, TNT, and TNP electrodes also exhibit similar behaviors. The enhanced efficiency of the TNT/TNP bi-layer electrode is found to be mainly due to the enhancement of charge collection efficiency, which is confirmed by the charge transport parameters measured by electrochemical impedance spectroscopy (EIS). EIS analyses also revealed that the TNT/TNP incurs smaller charge transport resistances and longer electron life times when compared to those of TNT or TNP electrodes alone. It was demonstrated that the TNT/TNP bi-layer electrode can possess the advantages of both rapid electron transport rate and a high light scattering effect.

  16. Halogen Bonding Promotes Higher Dye-Sensitized Solar Cell Photovoltages.

    PubMed

    Simon, Sarah J C; Parlane, Fraser G L; Swords, Wesley B; Kellett, Cameron W; Du, Chuan; Lam, Brian; Dean, Rebecca K; Hu, Ke; Meyer, Gerald J; Berlinguette, Curtis P

    2016-08-24

    We report here an enhancement in photovoltage for dye-sensitized solar cells (DSSCs) where halogen-bonding interactions exist between a nucleophilic electrolyte species (I(-)) and a photo-oxidized dye immobilized on a TiO2 surface. The triarylamine-based dyes under investigation showed larger rate constants for dye regeneration (kreg) by the nucleophilic electrolyte species when heavier halogen substituents were positioned on the dye. The open-circuit voltages (VOC) tracked these kreg values. This analysis of a homologous series of dyes that differ only in the identity of two halogen substituents provides compelling evidence that the DSSC photovoltage is sensitive to kreg. This study also provides the first direct evidence that halogen-bonding interactions between the dye and the electrolyte can bolster DSSC performance. PMID:27518595

  17. Intermediate Bandgap Solar Cells From Nanostructured Silicon

    SciTech Connect

    Black, Marcie

    2014-10-30

    This project aimed to demonstrate increased electronic coupling in silicon nanostructures relative to bulk silicon for the purpose of making high efficiency intermediate bandgap solar cells using silicon. To this end, we formed nanowires with controlled crystallographic orientation, small diameter, <111> sidewall faceting, and passivated surfaces to modify the electronic band structure in silicon by breaking down the symmetry of the crystal lattice. We grew and tested these silicon nanowires with <110>-growth axes, which is an orientation that should produce the coupling enhancement.

  18. Spectral Studies of UV and Solar Photocatalytic Degradation of AZO Dye and Textile Dye Effluents Using Green Synthesized Silver Nanoparticles

    PubMed Central

    Mariselvam, R.; Ranjitsingh, A. J. A.; Mosae Selvakumar, P.; Alarfaj, Abdullah A.; Munusamy, Murugan A.

    2016-01-01

    The photocatalytic degradation of the chemical dye AZO and dye effluents in different time duration has been investigated using biologically synthesized silver nanoparticles. Dye industry effluents and AZO dye undergo degradation to form harmless intermediate and colourless products following irradiation by UV and solar light in the presence of green synthesized silver nanoparticles. The degree of degradation was tested under the experimental conditions such as PH, temperature, and absorbance of the dye in UV and solar light was measured. The degradation was higher in the UV light source than in the solar light source. Green synthesized silver nanoparticles in the UV light source were found to expedite the dye degradation process. PMID:27382364

  19. Review on the application of nanostructure materials in solar cells

    NASA Astrophysics Data System (ADS)

    Afshar, Elham N.; Xosrovashvili, Georgi; Rouhi, Rasoul; Gorji, Nima E.

    2015-07-01

    In recent years, nanostructure materials have opened a promising route to future of the renewable sources, especially in the solar cells. This paper considers the advantages of nanostructure materials in improving the performance and stability of the solar cell structures. These structures have been employed for various performance/energy conversion enhancement strategies. Here, we have investigated four types of nanostructures applied in solar cells, where all of them are named as quantum solar cells. We have also discussed recent development of quantum dot nanoparticles and carbon nanotubes enabling quantum solar cells to be competitive with the conventional solar cells. Furthermore, the advantages, disadvantages and industrializing challenges of nanostructured solar cells have been investigated.

  20. Peptide-templating dye-sensitized solar cells.

    PubMed

    Han, Tae Hee; Moon, Hyoung-Seok; Hwang, Jin Ok; Seok, Sang Il; Im, Sang Hyuk; Kim, Sang Ouk

    2010-05-01

    A hollow TiO(2) nanoribbon network electrode for dye-sensitized solar cells (DSSC) was fabricated by a biotemplating process combining peptide self-assembly and atomic layer deposition (ALD). An aromatic peptide of diphenylalanine was assembled into a three-dimensional network consisting of highly entangled nanoribbons. A thin TiO(2) layer was deposited at the surface of the peptide template via the ALD process. After the pyrolysis of the peptide template, a highly entangled nanotubular TiO(2) framework was successfully prepared. Evolution of the crystal phase and crystallite size of the TiO(2) nanostructure was exploited by controlling the calcination temperature. Finally, the hollow TiO(2) nanoribbon network electrode was integrated into DSSC devices and their photochemical performances were investigated. Hollow TiO(2) nanoribbon-based DSSCs exhibited a power conversion efficiency of 3.8%, which is comparable to the conventional TiO(2) nanoparticle-based DSSCs (3.5%). Our approach offers a novel pathway for DSSCs consisting of TiO(2) electrodes via biotemplating. PMID:20378945

  1. Peptide-templating dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Han, Tae Hee; Moon, Hyoung-Seok; Hwang, Jin Ok; Seok, Sang Il; Im, Sang Hyuk; Ouk Kim, Sang

    2010-05-01

    A hollow TiO2 nanoribbon network electrode for dye-sensitized solar cells (DSSC) was fabricated by a biotemplating process combining peptide self-assembly and atomic layer deposition (ALD). An aromatic peptide of diphenylalanine was assembled into a three-dimensional network consisting of highly entangled nanoribbons. A thin TiO2 layer was deposited at the surface of the peptide template via the ALD process. After the pyrolysis of the peptide template, a highly entangled nanotubular TiO2 framework was successfully prepared. Evolution of the crystal phase and crystallite size of the TiO2 nanostructure was exploited by controlling the calcination temperature. Finally, the hollow TiO2 nanoribbon network electrode was integrated into DSSC devices and their photochemical performances were investigated. Hollow TiO2 nanoribbon-based DSSCs exhibited a power conversion efficiency of 3.8%, which is comparable to the conventional TiO2 nanoparticle-based DSSCs (3.5%). Our approach offers a novel pathway for DSSCs consisting of TiO2 electrodes via biotemplating.

  2. Bi-functional ion exchangers for enhanced performance of dye-sensitized solar cells.

    PubMed

    Kong, Eui-Hyun; Chang, Yong-June; Lim, Jongchul; Kim, Back-Hyun; Lee, Jung-Hoon; Kwon, Do-Kyun; Park, Taiho; Jang, Hyun Myung

    2013-07-28

    Ion exchange using aerosol OT (AOT) offers dye adsorption twice as fast as known methods. Moreover, it suppresses the dye-agglomeration that may cause insufficient dye-coverage on the photoelectrode surface. Consequently, its dual function of fast dye-loading and higher dye-coverage significantly improves the power conversion efficiency of dye-sensitized solar cells. PMID:23775416

  3. Vegetable-based dye-sensitized solar cells.

    PubMed

    Calogero, Giuseppe; Bartolotta, Antonino; Di Marco, Gaetano; Di Carlo, Aldo; Bonaccorso, Francesco

    2015-05-21

    There is currently a large effort to improve the performance of low cost renewable energy devices. Dye-sensitized solar cells (DSSCs) are emerging as one of the most promising low cost photovoltaic technologies, addressing "secure, clean and efficient solar energy conversion". Vegetable dyes, extracted from algae, flowers, fruit and leaves, can be used as sensitizers in DSSCs. Thus far, anthocyanin and betalain extracts together with selected chlorophyll derivatives are the most successful vegetable sensitizers. This review analyses recent progress in the exploitation of vegetable dyes for solar energy conversion and compares them to the properties of synthetic dyes. We provide an in-depth discussion on the main limitation of cell performance e.g. dye degradation, effective electron injection from the dye into the conduction band of semiconducting nanoparticles, such as titanium dioxide and zinc oxide, outlining future developments for the use of vegetable sensitizers in DSSCs. We also discuss the cost of vegetable dyes and how their versatility can boost the advancement of new power management solutions, especially for their integration in living environments, making the practical application of such systems economically viable. Finally, we present our view on future prospects in the development of synthetic analogues of vegetable dyes as sensitizers in DSSCs. PMID:25855097

  4. Incorporating hydrangea-like titanium dioxide light scatterer with high dye-loading on the photoanode for dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Chang, Wei-Chen; Tang, Bing-Hong; Lu, Yen-Wei; Yu, Wan-Chin; Lin, Lu-Yin; Wu, Ren-Jang

    2016-07-01

    The light scattering layer is significant for dye-sensitized solar cells (DSSCs) to harvest incident light more efficiently and excite larger amounts of electrons. Hydrangea-like TiO2 (Hsbnd TiO2) and coral-like TiO2 (Csbnd TiO2) nanostructures are synthesized via a hydrothermal method without using templates. Both of the nanostructures are applied as the light scattering layer for DSSCs with the commercial P90 TiO2 nanoparticles as the dye-adsorbed underlayer in the photoanodes. The DSSC with Hsbnd TiO2 as the light scattering layer achieves a higher light-to-electricity conversion efficiency (η) of 7.50% than those of 6.70% and 6.61% for the cells with Csbnd TiO2 and commercial TiO2 as the light scattering layer, and of 6.41% for the DSSC without a light scattering layer in its photoanode, mainly due to the enhanced photocurrent density through the abundant dye adsorption coupled with the inherent light scattering ability for the former case. The results indicate that not only the importance of the light scattering layer in the photoanode but the morphology of the nanostructure composed of the light scattering layer plays great roles on the light scattering and the dye-adsorbing capabilities. The incident photon-to-current efficiency the electrochemical impedance spectroscopy measurements are also applied to analyze the electrochemical performance of the resulting DSSCs.

  5. Efficiency Records in Mesoscopic Dye-Sensitized Solar Cells.

    PubMed

    Albero, Josep; Atienzar, Pedro; Corma, Avelino; Garcia, Hermenegildo

    2015-08-01

    The aim of the present review article is to show the progress achieved in the efficiency of dye-sensitized solar cells (DSSCs) by evolution in the structure and composition of the dye. After an initial brief description of DSSCs and the operating mechanism the major part of the present article is organized according to the type of dye, trying to show the logic in the variation of the dye structure in order to achieve strong binding on the surface of the layer of nanoparticulate TiO2 , efficient interfacial electron injection between the excited dye and the semiconductor, and minimization of the unwanted dark current processes. Besides metal complexes, including polypyridyls and nitrogenated macro rings, organic dyes and inorganic light harvesters such as quantum dots and perovskites have also been included in the review. The last section summarizes the current state of the art and provides an overview on future developments in the field. PMID:26183911

  6. Exploiting nanocarbons in dye-sensitized solar cells.

    PubMed

    Kavan, Ladislav

    2014-01-01

    Fullerenes, carbon nanotubes, nanodiamond, and graphene find various applications in the development of solar cells, including dye sensitized solar cells. Nanocarbons can be used as (1) active light-absorbing component, (2) current collector, (3) photoanode additive, or (4) counter electrode. Graphene-based materials have attracted considerable interest for catalytic counter electrodes, particularly in state-of-the-art dye sensitized solar cells with Co-mediators. The understanding of electrochemical charge-transfer at carbon surfaces is key to optimization of these solar cells, but the electrocatalysis on carbon surfaces is still a subject of conflicting debate. Due to the rich palette of problems at the interface of nanocarbons and photovoltaics, this review is selective rather than comprehensive. Its motivation was to highlight selected prospective inputs from nanocarbon science towards the development of novel dye sensitized solar cells with improved efficiency, durability, and cost. PMID:23729170

  7. Effectiveness of dye sensitised solar cell under low light condition using wide band dye

    SciTech Connect

    Sahmer, Ahmad Zahrin Mohamed, Norani Muti Zaine, Siti Nur Azella

    2015-07-22

    Dye sensistised solar cell (DSC) based on nanocrystalline TiO{sub 2} has the potential to be used in indoor consumer power application. In realizing this, the DSC must be optimized to generate power under low lighting condition and under wider visible light range. The use of wide band dye N749 which has a wider spectrum sensitivity increases the photon conversion to electron between the visible light spectrums of 390nm to 700nm. This paper reports the study on the effectiveness of the dye solar cell with N749 dye under low light condition in generating usable power which can be used for indoor consumer application. The DSC was fabricated using fluorine doped tin oxide (FTO) glass with screen printing method and the deposited TiO{sub 2} film was sintered at 500°C. The TiO{sub 2} coated FTO glass was then soaked in the N749 dye, assembled into test cell, and tested under the standard test condition at irradiance of 1000 W/m{sup 2} with AM1.5 solar soaker. The use of the 43T mesh for the dual pass screen printing TiO{sub 2} paste gives a uniform TiO{sub 2} film layer of 16 µm. The low light condition was simulated using 1/3 filtered irradiance with the solar soaker. The fabricated DSC test cell with the N749 dye was found to have a higher efficiency of 6.491% under low light condition compared to the N719 dye. Under the standard test condition at 1 sun the N749 test cell efficiency is 4.55%. The increases in efficiency is attributed to the wider spectral capture of photon of the DSC with N749 dye. Furthermore, the use of N749 dye is more effective under low light condition as the V{sub OC} decrement is less significant compared to the latter.

  8. Effectiveness of dye sensitised solar cell under low light condition using wide band dye

    NASA Astrophysics Data System (ADS)

    Sahmer, Ahmad Zahrin; Mohamed, Norani Muti; Zaine, Siti Nur Azella

    2015-07-01

    Dye sensistised solar cell (DSC) based on nanocrystalline TiO2 has the potential to be used in indoor consumer power application. In realizing this, the DSC must be optimized to generate power under low lighting condition and under wider visible light range. The use of wide band dye N749 which has a wider spectrum sensitivity increases the photon conversion to electron between the visible light spectrums of 390nm to 700nm. This paper reports the study on the effectiveness of the dye solar cell with N749 dye under low light condition in generating usable power which can be used for indoor consumer application. The DSC was fabricated using fluorine doped tin oxide (FTO) glass with screen printing method and the deposited TiO2 film was sintered at 500°C. The TiO2 coated FTO glass was then soaked in the N749 dye, assembled into test cell, and tested under the standard test condition at irradiance of 1000 W/m2 with AM1.5 solar soaker. The use of the 43T mesh for the dual pass screen printing TiO2 paste gives a uniform TiO2 film layer of 16 µm. The low light condition was simulated using 1/3 filtered irradiance with the solar soaker. The fabricated DSC test cell with the N749 dye was found to have a higher efficiency of 6.491% under low light condition compared to the N719 dye. Under the standard test condition at 1 sun the N749 test cell efficiency is 4.55%. The increases in efficiency is attributed to the wider spectral capture of photon of the DSC with N749 dye. Furthermore, the use of N749 dye is more effective under low light condition as the VOC decrement is less significant compared to the latter.

  9. Hydrothermal preparation of silver telluride nanostructures and photo-catalytic investigation in degradation of toxic dyes

    NASA Astrophysics Data System (ADS)

    Gholamrezaei, Sousan; Salavati-Niasari, Masoud; Ghanbari, Davood; Bagheri, Samira

    2016-01-01

    Different morphologies of Ag2Te nanostructures were synthesized using TeCl4 as a new precursor and hydrazine hydrate as reducing agent by a hydrothermal method. Various parameters that affect on morphology and purity of nanostructures were optimized. According to our experiments the best time and temperature for preparation of this nanostructure are 12 h and 120 °C. The photo-catalytic behaviour of nanostructures in presence of UV- visible light for degradation of methyl orange was investigated. Results show that the presence of UV light is necessary for an efficient degradation of dye in aqueous solution. On the other hand, as observations propose the Ag2Te reveal a strong photoluminescence peak at room temperature that could be attributed to high level transition in the semiconductor. Nanostructures were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared (FT-IR) techniques and UV-visible scanning spectrometer (UV-Vis).

  10. Hydrothermal preparation of silver telluride nanostructures and photo-catalytic investigation in degradation of toxic dyes

    PubMed Central

    Gholamrezaei, Sousan; Salavati-Niasari, Masoud; Ghanbari, Davood; Bagheri, Samira

    2016-01-01

    Different morphologies of Ag2Te nanostructures were synthesized using TeCl4 as a new precursor and hydrazine hydrate as reducing agent by a hydrothermal method. Various parameters that affect on morphology and purity of nanostructures were optimized. According to our experiments the best time and temperature for preparation of this nanostructure are 12 h and 120 °C. The photo-catalytic behaviour of nanostructures in presence of UV- visible light for degradation of methyl orange was investigated. Results show that the presence of UV light is necessary for an efficient degradation of dye in aqueous solution. On the other hand, as observations propose the Ag2Te reveal a strong photoluminescence peak at room temperature that could be attributed to high level transition in the semiconductor. Nanostructures were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared (FT-IR) techniques and UV–visible scanning spectrometer (UV-Vis). PMID:26805744

  11. Pre dye treated titanium dioxide nanoparticles synthesized by modified sol-gel method for efficient dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Ananth, S.; Vivek, P.; Arumanayagam, T.; Murugakoothan, P.

    2015-06-01

    Pure and pre dye treated titanium dioxide nanoparticles were prepared by sol-gel and modified sol-gel methods, respectively. The pre dye treatment has improved the properties of TiO2, such as uniform dye adsorption, reduced agglomeration, improved morphology and less dye aggregation. The brazilein pigment-rich Caesalpinia sappan heartwood extract was used as natural dye sensitizer for pure and pre dye treated TiO2 nanoparticles. Low cost and environment friendly dye-sensitized solar cells (DSSC) fabricated using pure and pre dye treated TiO2 nanoparticles sensitized by natural dye showed solar light to electron conversion efficiencies of 1.09 and 1.65 %, respectively. The pre dye treated TiO2-based DSSC showed 51 % improvement in efficiency when compared to that of conventionally prepared DSSC.

  12. Dye-sensitized solar cells using natural dyes as sensitizers from Malaysia local fruit `Buah Mertajam'

    NASA Astrophysics Data System (ADS)

    Hambali, N. A. M. Ahmad; Roshidah, N.; Hashim, M. Norhafiz; Mohamad, I. S.; Saad, N. Hidayah; Norizan, M. N.

    2015-05-01

    We experimentally demonstrate the high conversion efficiency, low cost, green technology and easy to fabricate dye-sensitized solar cells (DSSCs) using natural anthocyanin dyes as sensitizers. The DSSCs was fabricated by using natural anthocyanin dyes which were extracted from different parts of the plants inclusive `Buah Mertajam', `Buah Keriang Dot', `Bunga Geti', Hibiscus, Red Spinach and Henna. The natural anthocyanin dyes that found in flower, leaves and fruits were extracted by the simple procedures. This anthocyanin dye is used to replace the expensive chemical synthetic dyes due to its ability to effectively attach into the surface of Titanium dioxide (TiO2). A natural anthocyanin dyes molecule adsorbs to each particle of the TiO2 and acts as the absorber of the visible light. A natural anthocyanin dye from Buah Mertajam shows the best performance with the conversion efficiency of 5.948% and fill factor of 0.708 followed by natural anthocyanin dyes from `Buah Keriang Dot', `Bunga Geti', Hibiscus, Red Spinach and Henna. Buah Mertajam or scientifically known as eriglossum rubiginosum is a local Malaysia fruit.

  13. Efficient synthesis of triarylamine-based dyes for p-type dye-sensitized solar cells

    PubMed Central

    Wild, Martin; Griebel, Jan; Hajduk, Anna; Friedrich, Dirk; Stark, Annegret; Abel, Bernd; Siefermann, Katrin R.

    2016-01-01

    The class of triarylamine-based dyes has proven great potential as efficient light absorbers in inverse (p-type) dye sensitized solar cells (DSSCs). However, detailed investigation and further improvement of p-type DSSCs is strongly hindered by the fact that available synthesis routes of triarylamine-based dyes are inefficient and particularly demanding with regard to time and costs. Here, we report on an efficient synthesis strategy for triarylamine-based dyes for p-type DSSCs. A protocol for the synthesis of the dye-precursor (4-(bis(4-bromophenyl)amino)benzoic acid) is presented along with its X-ray crystal structure. The dye precursor is obtained from the commercially available 4(diphenylamino)benzaldehyde in a yield of 87% and serves as a starting point for the synthesis of various triarylamine-based dyes. Starting from the precursor we further describe a synthesis protocol for the dye 4-{bis[4′-(2,2-dicyanovinyl)-[1,1′-biphenyl]-4-yl]amino}benzoic acid (also known as dye P4) in a yield of 74%. All synthesis steps are characterized by high yields and high purities without the need for laborious purification steps and thus fulfill essential requirements for scale-up. PMID:27196877

  14. Efficient synthesis of triarylamine-based dyes for p-type dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Wild, Martin; Griebel, Jan; Hajduk, Anna; Friedrich, Dirk; Stark, Annegret; Abel, Bernd; Siefermann, Katrin R.

    2016-05-01

    The class of triarylamine-based dyes has proven great potential as efficient light absorbers in inverse (p-type) dye sensitized solar cells (DSSCs). However, detailed investigation and further improvement of p-type DSSCs is strongly hindered by the fact that available synthesis routes of triarylamine-based dyes are inefficient and particularly demanding with regard to time and costs. Here, we report on an efficient synthesis strategy for triarylamine-based dyes for p-type DSSCs. A protocol for the synthesis of the dye-precursor (4-(bis(4-bromophenyl)amino)benzoic acid) is presented along with its X-ray crystal structure. The dye precursor is obtained from the commercially available 4(diphenylamino)benzaldehyde in a yield of 87% and serves as a starting point for the synthesis of various triarylamine-based dyes. Starting from the precursor we further describe a synthesis protocol for the dye 4-{bis[4‧-(2,2-dicyanovinyl)-[1,1‧-biphenyl]-4-yl]amino}benzoic acid (also known as dye P4) in a yield of 74%. All synthesis steps are characterized by high yields and high purities without the need for laborious purification steps and thus fulfill essential requirements for scale-up.

  15. Efficient synthesis of triarylamine-based dyes for p-type dye-sensitized solar cells.

    PubMed

    Wild, Martin; Griebel, Jan; Hajduk, Anna; Friedrich, Dirk; Stark, Annegret; Abel, Bernd; Siefermann, Katrin R

    2016-01-01

    The class of triarylamine-based dyes has proven great potential as efficient light absorbers in inverse (p-type) dye sensitized solar cells (DSSCs). However, detailed investigation and further improvement of p-type DSSCs is strongly hindered by the fact that available synthesis routes of triarylamine-based dyes are inefficient and particularly demanding with regard to time and costs. Here, we report on an efficient synthesis strategy for triarylamine-based dyes for p-type DSSCs. A protocol for the synthesis of the dye-precursor (4-(bis(4-bromophenyl)amino)benzoic acid) is presented along with its X-ray crystal structure. The dye precursor is obtained from the commercially available 4(diphenylamino)benzaldehyde in a yield of 87% and serves as a starting point for the synthesis of various triarylamine-based dyes. Starting from the precursor we further describe a synthesis protocol for the dye 4-{bis[4'-(2,2-dicyanovinyl)-[1,1'-biphenyl]-4-yl]amino}benzoic acid (also known as dye P4) in a yield of 74%. All synthesis steps are characterized by high yields and high purities without the need for laborious purification steps and thus fulfill essential requirements for scale-up. PMID:27196877

  16. Challenges in the simulation of dye-sensitized ZnO solar cells: quantum confinement, alignment of energy levels and excited state nature at the dye/semiconductor interface.

    PubMed

    Amat, Anna; De Angelis, Filippo

    2012-08-14

    We report a first principles density functional theory/time-dependent density functional theory (DFT/TDDFT) computational investigation on a prototypical perylene dye anchored to realistic ZnO nanostructures, approaching the size of the ZnO nanowires used in dye-sensitized solar cells devices. DFT calculations were performed on (ZnO)(n) clusters of increasing size, with n up to 222, of 1.3 × 1.5 × 3.4 nm dimensions, and for the related dye-sensitized models. We show that quantum confinement in the ZnO nanostructures substantially affects the dye/semiconductor alignment of energy levels, with smaller ZnO models providing unfavourable electron injection. An increasing broadening of the dye LUMO is found moving to larger substrates, substantially contributing to the interfacial electronic coupling. TDDFT excited state calculations for the investigated dye@(ZnO)(222) system are fully consistent with experimental data, quantitatively reproducing the red-shift and broadening of the visible absorption spectrum observed for the ZnO-anchored dye compared to the dye in solution. TDDFT calculations on the fully interacting system also introduce a contribution to the dye/semiconductor admixture, due to configurational excited state mixing. Our results highlight the importance of quantum confinement in dye-sensitized ZnO interfaces, and provide the fundamental insight lying at the heart of the associated DSC devices. PMID:22743544

  17. Diffusion of dye solution in the intermolecular nanostructure of polydimethylsiloxane

    NASA Astrophysics Data System (ADS)

    Saito, Mitsunori; Nishimura, Tatsuya; Sakiyama, Kohei; Nakagawa, Michinori

    2012-09-01

    Polydimethylsiloxane (PDMS) contains a large, flexible free space between weakly-bonded molecules, which allows notable molecular diffusion. A toluene solution of diarylethene (photochromic dye) was mixed with a PDMS oil, and then the mixture was cured in a glass vessel by adding a curing agent. Violet laser (405 nm wavelength) irradiation induced an absorption band at around 530 nm, and consequently, the irradiated portion exhibited a red color. The colored portion gradually expanded to the entire sample because of diffusion of the dye molecules. This diffusion characteristic was used for improving an organic dye durability against a photo-induced degradation.

  18. Can aliphatic anchoring groups be utilised with dyes for p-type dye sensitized solar cells?

    PubMed

    Hao, Yan; Wood, Christopher J; Clark, Charlotte A; Calladine, James A; Horvath, Raphael; Hanson-Heine, Magnus W D; Sun, Xue-Zhong; Clark, Ian P; Towrie, Michael; George, Michael W; Yang, Xichuan; Sun, Licheng; Gibson, Elizabeth A

    2016-05-01

    A series of novel laterally anchoring tetrahydroquinoline derivatives have been synthesized and investigated for their use in NiO-based p-type dye-sensitized solar cells. The kinetics of charge injection and recombination at the NiO-dye interface for these dyes have been thoroughly investigated using picosecond transient absorption and time-resolved infrared measurements. It was revealed that despite the anchoring unit being electronically decoupled from the dye structure, charge injection occurred on a sub picosecond timescale. However, rapid recombination was also observed due to the close proximity of the electron acceptor on the dyes to the NiO surface, ultimately limiting the performance of the p-DSCs. PMID:27055102

  19. TiO2-coated nanostructures for dye photo-degradation in water

    PubMed Central

    2014-01-01

    The photocatalytic efficiency of a thin-film TiO2-coated nanostructured template is studied by dye degradation in water. The nanostructured template was synthesized by metal-assisted wet etching of Si and used as substrate for the deposition of a thin film of TiO2 (10 nm thick) by atomic layer deposition. A complete structural characterization was made by scanning and transmission electron microscopies. The significant photocatalytic performance was evaluated by the degradation of two dyes in water: methylene blue and methyl orange. The relevance of the reported results is discussed, opening the route toward the application of the synthesized nanostructured TiO2 for water purification. PMID:25246868

  20. π-Spacer effect in dithiafulvenyl-π-phenothiazine dyes for dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Zhang, Xiaofeng; Gou, Faliang; Zhao, Dongning; Shi, Jian; Gao, Hong; Zhu, Zhenping; Jing, Huanwang

    2016-08-01

    New dithiafulvenyl-π-phenothiazine dyes have been devised and prepared for dye-sensitized solar cells. Various π-spacers have been successfully introduced into the skeleton of dithiafulvenyl and phenothiazine unit to generate novel D-π-D-A dyes (DPP-1 ∼ 4). All dyes have been characterized with NMR, HRMS, UV-vis and fluorescence spectra, and taken into cyclic voltammetry measurements. The devices of new dyes have been determined by photoelectrochemical experiments (IV, IPCE and EIS), in which, solar cell of DPP-4 with biphenyl ring π-spacer enhances obviously its photoelectric conversion efficiency to 7.66% reaching 94% of N719-based standard cell and displays good long-term stability with quasi-solid-state electrolyte. Density functional theory (DFT) calculations of new dyes provide further insight into the molecular geometries and the impacts of the torsion angles on their photovoltaic performance. Large dihedral angles in DPP dyes induce good charge separation for efficient unidirectional flow of electron from donor to acceptor.

  1. π-Spacer effect in dithiafulvenyl-π-phenothiazine dyes for dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Zhang, Xiaofeng; Gou, Faliang; Zhao, Dongning; Shi, Jian; Gao, Hong; Zhu, Zhenping; Jing, Huanwang

    2016-08-01

    New dithiafulvenyl-π-phenothiazine dyes have been devised and prepared for dye-sensitized solar cells. Various π-spacers have been successfully introduced into the skeleton of dithiafulvenyl and phenothiazine unit to generate novel D-π-D-A dyes (DPP-1 ∼ 4). All dyes have been characterized with NMR, HRMS, UV-vis and fluorescence spectra, and taken into cyclic voltammetry measurements. The devices of new dyes have been determined by photoelectrochemical experiments (IV, IPCE and EIS), in which, solar cell of DPP-4 with biphenyl ring π-spacer enhances obviously its photoelectric conversion efficiency to 7.66% reaching 94% of N719-based standard cell and displays good long-term stability with quasi-solid-state electrolyte. Density functional theory (DFT) calculations of new dyes provide further insight into the molecular geometries and the impacts of the torsion angles on their photovoltaic performance. Large dihedral angles in DPP dyes induce good charge separation for efficient unidirectional flow of electron from donor to acceptor.

  2. Proficiency of acceptor-donor-acceptor organic dye with spiro-MeOTAD HTM on the photovoltaic performance of dye sensitized solar cell

    NASA Astrophysics Data System (ADS)

    Ramavenkateswari, K.; Venkatachalam, P.

    2016-08-01

    This work investigates the proficiency of acceptor-donor-acceptor (A-D-A) organic dye Diisopropyl azodicarboxylate (DIAC) as photosensitizer on the photovoltaic parameters of silver (Ag) doped TiO2 photoanode dye-sensitized solar cells (DSSCs) with quasi-solid state electrolyte/hole transport material (HTM) spiro-MeOTAD. TNSs (TiO2 nanosticks) photoanodes are prepared through sol-gel method and hydrothermal technique. X-ray powder diffraction (XRD), transmission electron microscope (TEM), scanning electron microscopy (SEM) and BET measurement were used to characterize the structure and morphology of TiO2 nanostructures. The Diisopropyl azodicarboxylate organic dye with TNPs-Ag@TNSs composite photoanode structure and spiro-MeOTAD HTM exhibited better power conversion efficiency (PCE). [Figure not available: see fulltext.

  3. Optimization of nanoparticle structure for improved conversion efficiency of dye solar cell

    SciTech Connect

    Mohamed, Norani Muti; Zaine, Siti Nur Azella

    2014-10-24

    Heavy dye loading and the ability to contain the light within the thin layer (typically ∼12 μm) are the requirement needed for the photoelectrode material in order to enhance the harvesting efficiency of dye solar cell. This can be realized by optimizing the particle size with desirable crystal structure. The paper reports the investigation on the dependency of the dye loading and light scattering on the properties of nanostructured photoelectrode materials by comparing 4 different samples of TiO{sub 2} in the form of nanoparticles and micron-sized TiO{sub 2} aggregates which composed of nanocrystallites. Their properties were evaluated by using scanning electron microscopy, X-ray diffraction and UVVis spectroscopy while the performance of the fabricated test cells were measured using universal photovoltaic test system (UPTS) under 1000 W/cm{sup 2} intensity of radiation. Nano sized particles provide large surface area which allow for greater dye adsorption but have no ability to retain the incident light in the TiO{sub 2} film. In contrast, micron-sized particles in the form of aggregates can generate light scattering allowing the travelling distance of the light to be extended and increasing the interaction between the photons and dye molecules adsorb on TiO{sub 2}nanocrystallites. This resulted in an improvement in the conversion efficiency of the aggregates that demonstrates the close relation between light scattering effect and the structure of the photolectrode film.

  4. Rapid double-dye-layer coating for dye-sensitized solar cells using a new method.

    PubMed

    Jung, Cho-long; Han, Chi-Hwan; Moon, Doo Kyung; Jun, Yongseok

    2014-10-01

    Intensive research with the specific aim of developing inexpensive renewable energy sources is currently being undertaken. In dye-sensitized solar cell (DSSC) production, the most time-consuming process is coating the dye on working electrodes: absorption of ruthenium-based dyes [e.g., N719=bis(trtrabutylammonium)-cis-di(thiocyanato)-N,N'-bis(4-carboxylato-4'-carboxylic acid-2,2'-bipyridine) ruthenium(II)] on a photoanode takes a long time. We report a simple dye-coating method using a mixed solvent of ethylene glycol (EG) and glycerol (Gly). According to our experiments, dye-coating time can be reduced to 5 min from several hours. Maximum performance was obtained with an EG/Gly ratio of 1:1. This mixture of solvents gave a performance of 9.1%. Furthermore, the viscous solvent system could control coating depth; positioning dye coatings to a specific depth was rapid and facile. A cell containing two different dyes (N719+black dye) had an efficiency of 9.4%. PMID:25154611

  5. Extension lifetime for dye-sensitized solar cells through multiple dye adsorption/desorption process

    NASA Astrophysics Data System (ADS)

    Chiang, Yi-Fang; Chen, Ruei-Tang; Shen, Po-Shen; Chen, Peter; Guo, Tzung-Fang

    2013-03-01

    In this study, we propose a novel concept of extending the lifetime of dye-sensitized solar cells (DSCs) and reducing the costs of re-conditioning DSCs by recycling the FTO/TiO2 substrates. The photovoltaic performances of DSCs using substrates with various cycles of dye uptake and rinse off history are tested. The results show that dye adsorption and Voc are significantly increased under multiple dye adsorption/desorption process and resulted in the improvement of power conversion efficiency. Moreover, the dyeing kinetics is faster after multiple recycling processes, which is favorable for the industrial application. With surface analysis and charge transport characteristics, we also demonstrate the optimal functionality of TiO2/dye interface for the improved Voc and efficiency. The results confirm that the improved performances are due to increased dye loading and dense packing of dye molecules. Our results are beneficial for the understanding on the extension of DSCs lifetime after long-term operation in the application of DSC modules. This approach may also be applied in the replacement of newly synthesized photosensitizes to the active cells.

  6. Highly efficient photocathodes for dye-sensitized tandem solar cells.

    PubMed

    Nattestad, A; Mozer, A J; Fischer, M K R; Cheng, Y-B; Mishra, A; Bäuerle, P; Bach, U

    2010-01-01

    Thin-film dye-sensitized solar cells (DSCs) based on mesoporous semiconductor electrodes are low-cost alternatives to conventional silicon devices. High-efficiency DSCs typically operate as photoanodes (n-DSCs), where photocurrents result from dye-sensitized electron injection into n-type semiconductors. Dye-sensitized photocathodes (p-DSCs) operate in an inverse mode, where dye-excitation is followed by rapid electron transfer from a p-type semiconductor to the dye (dye-sensitized hole injection). Such p-DSCs and n-DSCs can be combined to construct tandem solar cells (pn-DSCs) with a theoretical efficiency limitation well beyond that of single-junction DSCs (ref. 4). Nevertheless, the efficiencies of such tandem pn-DSCs have so far been hampered by the poor performance of the available p-DSCs (refs 3, 5-15). Here we show for the first time that p-DSCs can convert absorbed photons to electrons with yields of up to 96%, resulting in a sevenfold increase in energy conversion efficiency compared with previously reported photocathodes. The donor-acceptor dyes, studied as photocathodic sensitizers, comprise a variable-length oligothiophene bridge, which provides control over the spatial separation of the photogenerated charge carriers. As a result, charge recombination is decelerated by several orders of magnitude and tandem pn-DSCs can be constructed that exceed the efficiency of their individual components. PMID:19946281

  7. Highly efficient photocathodes for dye-sensitized tandem solar cells

    NASA Astrophysics Data System (ADS)

    Nattestad, A.; Mozer, A. J.; Fischer, M. K. R.; Cheng, Y.-B.; Mishra, A.; Bäuerle, P.; Bach, U.

    2010-01-01

    Thin-film dye-sensitized solar cells (DSCs) based on mesoporous semiconductor electrodes are low-cost alternatives to conventional silicon devices. High-efficiency DSCs typically operate as photoanodes (n-DSCs), where photocurrents result from dye-sensitized electron injection into n-type semiconductors. Dye-sensitized photocathodes (p-DSCs) operate in an inverse mode, where dye-excitation is followed by rapid electron transfer from a p-type semiconductor to the dye (dye-sensitized hole injection). Such p-DSCs and n-DSCs can be combined to construct tandem solar cells (pn-DSCs) with a theoretical efficiency limitation well beyond that of single-junction DSCs (ref. 4). Nevertheless, the efficiencies of such tandem pn-DSCs have so far been hampered by the poor performance of the available p-DSCs (refs 3, 5-15). Here we show for the first time that p-DSCs can convert absorbed photons to electrons with yields of up to 96%, resulting in a sevenfold increase in energy conversion efficiency compared with previously reported photocathodes. The donor-acceptor dyes, studied as photocathodic sensitizers, comprise a variable-length oligothiophene bridge, which provides control over the spatial separation of the photogenerated charge carriers. As a result, charge recombination is decelerated by several orders of magnitude and tandem pn-DSCs can be constructed that exceed the efficiency of their individual components.

  8. Green grasses as light harvesters in dye sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Shanmugam, Vinoth; Manoharan, Subbaiah; Sharafali, A.; Anandan, Sambandam; Murugan, Ramaswamy

    2015-01-01

    Chlorophylls, the major pigments presented in plants are responsible for the process of photosynthesis. The working principle of dye sensitized solar cell (DSSC) is analogous to natural photosynthesis in light-harvesting and charge separation. In a similar way, natural dyes extracted from three types of grasses viz. Hierochloe Odorata (HO), Torulinium Odoratum (TO) and Dactyloctenium Aegyptium (DA) were used as light harvesters in dye sensitized solar cells (DSSCs). The UV-Vis absorption spectroscopy, Fourier transform infrared (FT-IR), and liquid chromatography-mass spectrometry (LC-MS) were used to characterize the dyes. The electron transport mechanism and internal resistance of the DSSCs were investigated by the electrochemical impedance spectroscopy (EIS). The performance of the cells fabricated with the grass extract shows comparable efficiencies with the reported natural dyes. Among the three types of grasses, the DSSC fabricated with the dye extracted from Hierochloe Odorata (HO) exhibited the maximum efficiency. LC-MS investigations indicated that the dominant pigment present in HO dye was pheophytin a (Pheo a).

  9. Progress and Design Concerns of Nanostructured Solar Energy Harvesting Devices.

    PubMed

    Leung, Siu-Fung; Zhang, Qianpeng; Tavakoli, Mohammad Mahdi; He, Jin; Mo, Xiaoliang; Fan, Zhiyong

    2016-05-01

    Integrating devices with nanostructures is considered a promising strategy to improve the performance of solar energy harvesting devices such as photovoltaic (PV) devices and photo-electrochemical (PEC) solar water splitting devices. Extensive efforts have been exerted to improve the power conversion efficiencies (PCE) of such devices by utilizing novel nanostructures to revolutionize device structural designs. The thicknesses of light absorber and material consumption can be substantially reduced because of light trapping with nanostructures. Meanwhile, the utilization of nanostructures can also result in more effective carrier collection by shortening the photogenerated carrier collection path length. Nevertheless, performance optimization of nanostructured solar energy harvesting devices requires a rational design of various aspects of the nanostructures, such as their shape, aspect ratio, periodicity, etc. Without this, the utilization of nanostructures can lead to compromised device performance as the incorporation of these structures can result in defects and additional carrier recombination. The design guidelines of solar energy harvesting devices are summarized, including thin film non-uniformity on nanostructures, surface recombination, parasitic absorption, and the importance of uniform distribution of photo-generated carriers. A systematic view of the design concerns will assist better understanding of device physics and benefit the fabrication of high performance devices in the future. PMID:26918386

  10. Ultrafast interfacial charge transfer dynamics in dye-sensitized and quantum dot solar cell

    NASA Astrophysics Data System (ADS)

    Ghosh, Hirendra N.

    2013-02-01

    Dye sensitized solar cell (DSSC) appeared to be one of the good discovery for the solution of energy problem. We have been involved in studying ultrafast interfacial electron transfer dynamics in DSSC using femtosecond laser spectroscopy. However it has been realized that it is very difficult to design and develop higher efficient one, due to thermodynamic limitation. Again in DSSC most of the absorbed photon energy is lost as heat within the cell, which apart from decreasing the efficiency also destabilizes the device. It has been realized that quantum dot solar cell (QDSC) are the best bet where the sensitizer dye molecules can be replaced by suitable quantum dot (QD) materials in solar cell. The quantum-confinement effect in semiconductors modifies their electronic structure, which is a very important aspect of these materials. For photovoltaic applications, a long-lived charge separation remains one of the most essential criteria. One of the problems in using QDs for photovoltaic applications is their fast charge recombination caused by nonradiative Auger processes, which occur predominantly at lower particle sizes due to an increase in the Coulomb interaction between electrons and holes. Various approaches, such as the use of metal-semiconductor composites, semiconductor-polymer composite, and semiconductor core-shell heterostructures, have been attempted to minimize the fast recombination between electrons and holes. To make higher efficient solar devices it has been realised that it is very important to understand charge carrier and electron transfer dynamics in QD and QD sensitized semiconductor nanostructured materials. In the present talk, we are going to discuss on recent works on ultrafast electron transfer dynamics in dye-sensitized TiO2 nanoparticles/film [1-12] and charge (electron/hole) transfer dynamics in quantum dot core-shell nano-structured materials [13-17].

  11. Analysis and simulation of incident photon to current efficiency in dye sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Gentilini, D.; D'Ercole, D.; Gagliardi, A.; Brunetti, A.; Reale, A.; Brown, T.; Di Carlo, A.

    2010-01-01

    Conversion of solar energy into electricity is a challenging issue of today's renewable energy. Electrochemical dye solar cells (DSC), based on nanostructured TiO 2 particles are a very promising class of photovoltaic devices [6]. The mechanism beyond the conversion of the light is quite different from any other solid state solar cell, resulting from the interplay of a fine tuning of the energy levels of the cell components and a delicate fabrication process. This complexity needs a reliable transport model, able to catch the device as a whole and applicable to experimental set up. We developed an extension of TiberCAD [7] code to simulate such kind of devices and compared the calculation with incident photon to current efficiency (IPCE) measurements.

  12. Dye-Sensitized Solar Cells Combining ZnO Nanotip Arrays and Nonliquid Gel Electrolytes

    NASA Astrophysics Data System (ADS)

    Chen, Hanhong; Duan, Ziqing; Lu, Yicheng; Du Pasquier, Aurelien

    2009-08-01

    We present a dye-sensitized solar cell (DSSC) using a nanostructured ZnO photoelectrode and a gel electrolyte. The photoelectrode consists of well-aligned ZnO nanotips on a Ga-doped ZnO (GZO) transparent conducting film. The GZO film (400 nm, sheet resistance ~25 Ω/sq, transmittance over 85% in the visible wavelength) and ZnO nanotips (3.2 μm length) are sequentially grown on a glass substrate using metalorganic chemical vapor deposition. The ZnO photoelectrode is sensitized with dye N719 and impregnated with N-methyl pyrolidinone (NMP) gelled with poly(vinyl-difluoroethylene-hexafluoropropylene) copolymer (PVDF-HFP). The cell exhibits an open-circuit voltage of 726 mV and a power conversion efficiency of 0.89% under one sun illumination. The aging testing shows that the cell using a gel electrolyte has better stability than its liquid electrolyte counterpart.

  13. Cost-effective platinum alloy counter electrodes for liquid-junction dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Li, Yanjuan; Tang, Qunwei; Yu, Liangmin; Yan, Xuefeng; Dong, Lei

    2016-02-01

    One of the challenges in developing advanced dye-sensitized solar cells (DSSCs) is the pursuit of cost-effective and robust counter electrodes (CEs). We present here the successful synthesis of binary PtxM100-x (M = Ni, Co, Fe) alloy nanostructures on Ti foil by a facile and environmental-friendly strategy for utilization as CEs in liquid-junction DSSCs. Due to the reasonable charge-transfer ability and excellent electrocatalytic activity, the resultant DSSC yields a promising power conversion efficiency (PCE) of 6.42% with binary Pt0.28Ni99.72 CE in comparison with 6.18% for pristine Pt CE based device. The easy synthesis, cost-effectiveness, and good electrocatalytic property may help the Pt0.28Ni99.72 nanostructure stand out as an alternative CE electrocatalyst in a DSSC.

  14. Correlating Titania Morphology and Chemical Composition with Dye-sensitized Solar Cell Performance

    SciTech Connect

    Santulli, A.C.; Wong, S.; Koenigsmann, C.; Tiano, A.L., DeRosa, D.

    2011-04-20

    We have investigated the use of various morphologies, including nanoparticles, nanowires, and sea-urchins of TiO{sub 2} as the semiconducting material used as components of dye-sensitized solar cells (DSSCs). Analysis of the solar cells under AM 1.5 solar irradiation reveals the superior performance of hydrothermally derived nanoparticles, by comparison with two readily available commercial nanoparticle materials, within the DSSC architecture. The sub-structural morphology of films of these nanostructured materials has been directly characterized using SEM and indirectly probed using dye desorption. Furthermore, the surfaces of these nanomaterials were studied using TEM in order to visualize their structure, prior to their application within DSSCs. Surface areas of the materials have been quantitatively analyzed by collecting BET adsorption and dye desorption data. Additional investigation using open circuit voltage decay measurements reveals the efficiency of electron conduction through each TiO{sub 2} material. Moreover, the utilization of various chemically distinctive titanate materials within the DSSCs has also been investigated, demonstrating the deficiencies of using these particular chemical compositions within traditional DSSCs.

  15. Self-assembled ultra small ZnO nanocrystals for dye-sensitized solar cell application

    SciTech Connect

    Patra, Astam K.; Dutta, Arghya; Bhaumik, Asim

    2014-07-01

    We demonstrate a facile chemical approach to produce self-assembled ultra-small mesoporous zinc oxide nanocrystals using sodium salicylate (SS) as a template under hydrothermal conditions. These ZnO nanomaterials have been successfully fabricated as a photoanode for the dye-sensitized solar cell (DSSC) in the presence of N719 dye and iodine–triiodide electrolyte. The structural features, crystallinity, purity, mesophase and morphology of the nanostructure ZnO are investigated by several characterization tools. N{sub 2} sorption analysis revealed high surface areas (203 m{sup 2} g{sup −1}) and narrow pore size distributions (5.1–5.4 nm) for different samples. The mesoporous structure and strong photoluminescence facilitates the high dye loading at the mesoscopic void spaces and light harvesting in DSSC. By utilizing this ultra-small ZnO photoelectrode with film thickness of about 7 μm in the DSSC with an open-circuit voltage (V{sub OC}) of 0.74 V, short-circuit current density (J{sub SC}) of 3.83 mA cm{sup −2} and an overall power conversion efficiency of 1.12% has been achieved. - Graphical abstract: Ultra-small ZnO nanocrystals have been synthesized with sodium salicylate as a template and using it as a photoanode in a dye-sensitized solar cell 1.12% power conversion efficiency has been observed. - Highlights: • Synthesis of self-assembled ultra-small mesoporous ZnO nanocrystals by using sodium salicylate as a template. • Mesoporous ZnO materials have high BET surface areas and void space. • ZnO nanoparticles serve as a photoanode for the dye-sensitized solar cell (DSSC). • Using ZnO nanocrystals as photoelectrode power conversion efficiency of 1.12% has been achieved.

  16. Nanostructured Semiconductor Device Design in Solar Cells

    NASA Astrophysics Data System (ADS)

    Dang, Hongmei

    We demonstrate the use of embedded CdS nanowires in improving spectral transmission loss and the low mechanical and electrical robustness of planar CdS window layer and thus enhancing the quantum efficiency and the reliability of the CdS-CdTe solar cells. CdS nanowire window layer enables light transmission gain at 300nm-550nm. A nearly ideal spectral response of quantum efficiency at a wide spectrum range provides an evidence for improving light transmission in the window layer and enhancing absorption and carrier generation in absorber. Nanowire CdS/CdTe solar cells with Cu/graphite/silver paste as back contacts, on SnO2/ITO-soda lime glass substrates, yield the highest efficiency of 12% in nanostructured CdS-CdTe solar cells. Reliability is improved by approximately 3 times over the cells with the traditional planar CdS counterpart. Junction transport mechanisms are delineated for advancing the basic understanding of device physics at the interface. Our results prove the efficacy of this nanowire approach for enhancing the quantum efficiency and the reliability in windowabsorber type solar cells (CdS-CdTe, CdS-CIGS and CdS-CZTSSe etc) and other optoelectronic devices. We further introduce MoO3-x as a transparent, low barrier back contact. We design nanowire CdS-CdTe solar cells on flexible foils of metals in a superstrate device structure, which makes low-cost roll-to-roll manufacturing process feasible and greatly reduces the complexity of fabrication. The MoO3 layer reduces the valence band offset relative to the CdTe, and creates improved cell performance. Annealing as-deposited MoO3 in N 2 reduces series resistance from 9.98 O/cm2 to 7.72 O/cm2, and hence efficiency of the nanowire solar cell is improved from 9.9% to 11%, which efficiency comparable to efficiency of planar counterparts. When the nanowire solar cell is illuminated from MoO 3-x /Au side, it yields an efficiency of 8.7%. This reduction in efficiency is attributed to decrease in Jsc from 25.5m

  17. Natural dye extract of lawsonia inermis seed as photo sensitizer for titanium dioxide based dye sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Ananth, S.; Vivek, P.; Arumanayagam, T.; Murugakoothan, P.

    2014-07-01

    Natural dye extract of lawsonia inermis seed were used as photo sensitizer to fabricate titanium dioxide nanoparticles based dye sensitized solar cells. Pure titanium dioxide (TiO2) nanoparticles in anatase phase were synthesized by sol-gel technique and pre dye treated TiO2 nanoparticles were synthesized using modified sol-gel technique by mixing lawsone pigment rich natural dye during the synthesis itself. This pre dye treatment with natural dye has yielded colored TiO2 nanoparticles with uniform adsorption of natural dye, reduced agglomeration, less dye aggregation and improved morphology. The pure and pre dye treated TiO2 nanoparticles were subjected to structural, optical, spectral and morphological studies. Dye sensitized solar cells (DSSC) fabricated using the pre dye treated and pure TiO2 nanoparticles sensitized by natural dye extract of lawsonia inermis seed showed a promising solar light to electron conversion efficiency of 1.47% and 1% respectively. The pre dye treated TiO2 based DSSC showed an improved efficiency of 47% when compared to that of conventional DSSC.

  18. Third row metal complexes as an alternative dye in dye sensitized solar cell system

    NASA Astrophysics Data System (ADS)

    Wahyuningsih, S.; Ramelan, A. H.; Badriyah, I.; Kristy, I. O.; Dewi, N. S.; Rahardjo, S. B.

    2013-10-01

    Copper(II), Cobalt (II) and Iron (II) complexes as photosensitizer on Dye Sensitized Solar Cell (DSSC) had been investigated. The aim of this research is to find out the respond addition of those dyes on FTO/TiO2 (FTO = fluorine Tin Oxide) thin film to visible light and the effect of various third row complexes to DSSC performance. Slip casting method was used to fabricate FTO/TiO2 and FTO/carbon thin film. The result from FTO/TiO2 UV-Vis spectra show no absorption on visible light. Dye solution was synthesized from free metal ions of Cu(II), Co(II), and Fe(II) in methanol with diphenylamine (dpa), 2,2,bypiridine (bpy), 1,10, phenathroline (phen), 4,4'-dicarboxylic acid-2,2'-bipyridine (dcbq), and anthocyanin (ant) ligands, respectively. UV-Vis spectrophotometry was used to identify FTO/TiO2/dye with various sensitizer dyes. The performance of DSSC was determined by I (current) - V (voltage) curve using Keithley 2602 A System Source. In this research, DSSCs are able to convert photon energy become electrical energy. Dye used in DSSC is greatly effect in photon to current efficiency (IPCE). The greater absorption in visible region of alternative dye used gains higher IPCE spectra. TiO2 character can help spread the absorption in whole visible region. The nanosize mesoporous TiO2 of TiO2/SiPA/CoII-PAR (SiPA = silylpropilamine) have greater value than P25 TiO2/SiPA-CoII-PAR. The SiPA/FeII-PAR and SiPA/CoII-PAR dyes are better dye than tpa.

  19. Aerogel tempelated ZnO dye-sensitized solar cells.

    SciTech Connect

    Hamann, T. W.; Martinson , A. B. E.; Elam, J. W.; Pellin, M. J.; Hupp, J. T.; Materials Science Division; Northwestern Univ.

    2008-01-01

    Atomic layer deposition is employed to conformally coat low density, high surface area aerogel films with ZnO. The ZnO/aerogel membranes are incorporated as photoanodes in dye-sensitized solar cells, which exhibit excellent power efficiencies of up to 2.4% under 100 mW cm{sup -2} light intensity.

  20. Hierarchically Structured ZnO Film for Dye-Sensitized Solar Cells with Enhanced Energy Conversion Efficiency

    SciTech Connect

    Chou, Tammy P.; Zhang, Qifeng; Fryxell, Glen E.; Cao, Guozhong

    2007-09-17

    The interest in dye-sensitized solar cells has increased due to reduced energy sources and higher energy production costs. For the most part, titania (TiO2) has been the material of choice for dye-sensitized solar cells and so far have shown to exhibit the highest overall light conversion efficiency ~ 11%.[1] However, zinc oxide (ZnO) has recently been explored as an alternative material in dye-sensitized solar cells with great potential.[2] The main reasons for this increase in research surrounding ZnO material include: 1) ZnO having a band gap similar to that for TiO2 at 3.2 eV,[3] and 2) ZnO having a much higher electron mobility ~ 115-155 cm2/Vs[4] than that for anatase titania (TiO2), which is reported to be ~ 10-5 cm2/Vs.[5] In addition, ZnO has a few advantages as the semiconductor electrode when compared to TiO2, including 1) simpler tailoring of the nanostructure as compared to TiO2, and 2) easier modification of the surface structure. These advantages[6] are thought to provide a promising means for improving the solar cell performance of the working electrode in dye-sensitized solar cells.

  1. Triphenylamine based organic dyes for dye sensitized solar cells: A theoretical approach

    NASA Astrophysics Data System (ADS)

    Mohankumar, V.; Pandian, Muthu Senthil; Ramasamy, P.

    2016-05-01

    The geometry, electronic structure and absorption spectra for newly designed triphenylamine based organic dyes were investigated by density functional theory (DFT) and time dependent density functional theory (TD-DFT) with the Becke 3-Parameter-Lee-Yang-parr(B3LYP) functional, where the 6-31G(d,p) basis set was employed. All calculations were performed using the Gaussian 09 software package. The calculated HOMO and LUMO energies show that charge transfer occurs in the molecule. Ultraviolet-visible (UV-vis) spectrum was simulated by TD-DFT in gas phase. The calculation shows that all of the dyes can potentially be good sensitizers for DSSC. The LUMOs are just above the conduction band of TiO2 and their HOMOs are under the reduction potential energy of the electrolytes (I-/I3-) which can facilitate electron transfer from the excited dye to TiO2 and charge regeneration process after photo oxidation respectively. The simulated absorption spectrum of dyes match with solar spectrum. Frontier molecular orbital results show that among all the three dyes, the "dye 3" can be used as potential sensitizer for DSSC.

  2. Hydrothermally growth of novel hierarchical structures titanium dioxide for high efficiency dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Cheng, Pengfei; Liu, Yang; Sun, Peng; Du, Sisi; Cai, Yaxin; Liu, Fengmin; Zheng, Jie; Lu, Geyu

    2014-12-01

    We report an innovative development of novel double layered photoanodes made of hierarchical TiO2 micro-corollas as the overlayer and TiO2 nanoforest as the underlayer (HTCF), for dye-sensitized solar cells (DSSCs). They are obtained by a facile hydrothermal reaction of TiO2 nanorods array with top microspheres (MS)/FTO (Fluorine-doped tin oxide) glass substrate in an alkaline solution. In this process, the microspheres and nanorods are transformed into micro-corollas and nanotrees, respectively. The photoanodes with HTCF structure can greatly improve the light scattering ability due to their novel structures. Moreover, the enhanced surface area of HTCF can lead to larger dye loading, which achieves the higher light harvesting capacity. Base on the fast electron transport of the interior nanorods, higher light scattering and harvesting capacities, this novel HTCF photoanode realizes tri-functions. The overall power conversion efficiency (PCE) of the HTCF DSSCs are 51% increase in the conversion efficiency compare with those of constructed by bare TiO2 nanorod arrays. In our work, tri-functions of photoanodes are obtained by improving the 1D TiO2 nanostructures (nanorod, nanowire, nanotube et al.). To the best of our knowledge, it is a significant fabrication technology breakthrough for the photoanode of dye-sensitized solar cells.

  3. Hierarchical growth of fluorescent dye aggregates in water by fusion of segmented nanostructures.

    PubMed

    Zhang, Xin; Görl, Daniel; Stepanenko, Vladimir; Würthner, Frank

    2014-01-27

    Dye aggregates are becoming increasingly attractive for diverse applications, in particular as organic electronic and sensor materials. However, the growth processes of such aggregates from molecular to small assemblies up to nanostructures is still not properly understood, limiting the design of materials' functional properties. Here we elucidate the supramolecular growth process for an outstanding class of functional dyes, perylene bisimides (PBIs), by transmission electron microscopy (TEM), cryogenic scanning electron microscopy (cryo-SEM), and atomic force microscopy (AFM). Our studies reveal a sequential growth of amphiphilic PBI dyes from nanorods into nanoribbons in water by fusion and fission processes. More intriguingly, the fluorescence observed for higher hierarchical order nanoribbons was enhanced relative to that of nanorods. Our results provide insight into the relationship between molecular, morphological, and functional properties of self-assembled organic materials. PMID:24352910

  4. Morphology Dependent Photocatalytic Activity of α-MoO3 Nanostructures Towards Mutagenic Acridine Orange Dye.

    PubMed

    2015-06-01

    The morphological evolutions of orthorhombic molybdenum oxide nanostructures with high crystalline nature have been successfully synthesized by combining low-temperature sol-gel and annealing processes. Strong influence of gelation temperature is a factor facilitated to control the material morphology. Morphological transformations like nanospheres, nanoplatelets, mixtures of hexagonal platelets, and one-dimensional nanobars were obtained. The possible morphological formation mechanism has been proposed as a self-assemble process of nucleation and a mechanism for particle growth by Ostwald ripening. The as-prepared nanostructures were recognized as photocatalysts for the degradation of Acridine Orange under Ultra Violet light. The obtained mixed morphology (hexagonal nanoplatelets and nanobars) showed a high photocatalytic property to degrade mutagenic Acridine Orange dye. Moreover, they could be easily recycled without changing the photocatalytic activity due to their 1-Dimensional and 2-Dimensional nanostructure property. PMID:26369043

  5. Gold nanoparticle decorated multi-walled carbon nanotubes as counter electrode for dye sensitized solar cells.

    PubMed

    Kaniyoor, Adarsh; Ramaprabhu, Sundara

    2012-11-01

    A novel counter electrode material for dye sensitized solar cells (DSSCs) composed of nanostructured Au particles decorated on functionalized multi-walled carbon nanotubes (f-MWNTs) is demonstrated for the first time. MWNTs synthesized by catalytic chemical vapor deposition technique are purified and functionalized by treating with concentrated acids. Au nanoparticles are decorated on f-MWNTs by a rapid and facile microwave assisted polyol reduction method. The materials are characterized by X-ray diffractometry, Fourier transform infra red spectroscopy and electron microscopy. The DSSC fabricated with Au/f-MWNTs based counter electrode shows enhanced power conversion efficiency (eta) of 4.9% under AM 1.5G simulated solar radiation. In comparison, the reference DSSCs fabricated with f-MWNTs and Pt counter electrodes show eta of 2.1% and 4.5%. This high performance of Au/f-MWNTs counter electrode is investigated using electrochemical impedance spectroscopy and cyclic voltammetry studies. PMID:23421212

  6. Dyes extracted from Trigonella seeds as photosensitizers for dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Batniji, Amal; Abdel-Latif, Monzir S.; El-Agez, Taher M.; Taya, Sofyan A.; Ghamri, Hatem

    2016-06-01

    In this paper, the extract of Trigonella seeds was used as sensitizer for dye-sensitized solar cells (DSSCs). The natural dye was extracted from the seeds using water and alcohol as solvents for the raw material. The UV-Vis absorption spectra of Trigonella extract solution and dye adsorbed on TiO2 film were measured. DSSCs sensitized by Trigonella extracted using water as a solvent exhibited better performance with efficiency of 0.215 %. The performance of the fabricated DSSCs was attempted to enhance by acid treatment of the FTO substrates with HNO3, H3PO4, and H2SO4. Electrochemical impedance spectroscopy of the fabricated cells was also carried out.

  7. Oligothiophene-linked D-π-A type phenothiazine dyes for dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Gao, Huan-Huan; Qian, Xing; Chang, Wen-Ying; Wang, Shan-Shan; Zhu, Yi-Zhou; Zheng, Jian-Yu

    2016-03-01

    Three novel phenothiazine dyes (JY31-33) featured oligothiophene π-bridge have been designed, synthesized and applied as photosensitizers for highly efficient dye-sensitized solar cells (DSSCs). The introduction of alkyl chains on oligothiophene π-bridge is found to significantly improve the open-circuit voltage of the resultant device. Phenothiazine bearing a 4-butoxyphenyl group as the secondary donor exhibits a stronger electron-donating ability and a positive acceleration on the short-circuit current density and open-circuit voltage. The dye JY33 containing a secondary donor and two alkyl chains finally gives a high efficiency of 7.48% under the 100 mW cm-2 simulated AM1.5 sunlight, with a short-circuit photocurrent density (Jsc) of 17.18 mA cm-2, an open-circuit photovoltage (Voc) of 742 mV and a fill factor (FF) of 0.59.

  8. High-efficiency nanostructured window GaAs solar cells.

    PubMed

    Liang, Dong; Kang, Yangsen; Huo, Yijie; Chen, Yusi; Cui, Yi; Harris, James S

    2013-10-01

    Nanostructures have been widely used in solar cells due to their extraordinary optical properties. In most nanostructured cells, high short circuit current has been obtained due to enhanced light absorption. However, most of them suffer from lowered open circuit voltage and fill factor. One of the main challenges is formation of good junction and electrical contact. In particular, nanostructures in GaAs only have shown unsatisfactory performances (below 5% in energy conversion efficiency) which cannot match their ideal material properties and the record photovoltaic performances in industry. Here we demonstrate a completely new design for nanostructured solar cells that combines nanostructured window layer, metal mesa bar contact with small area, high quality planar junction. In this way, we not only keep the advanced optical properties of nanostructures such as broadband and wide angle antireflection, but also minimize its negative impact on electrical properties. High light absorption, efficient carrier collection, leakage elimination, and good lateral conductance can be simultaneously obtained. A nanostructured window cell using GaAs junction and AlGaAs nanocone window demonstrates 17% energy conversion efficiency and 0.982 V high open circuit voltage. PMID:24021024

  9. Hydrothermal preparation of silver telluride nanostructures and photo-catalytic investigation in degradation of toxic dyes.

    PubMed

    Gholamrezaei, Sousan; Salavati-Niasari, Masoud; Ghanbari, Davood; Bagheri, Samira

    2016-01-01

    Different morphologies of Ag2Te nanostructures were synthesized using TeCl4 as a new precursor and hydrazine hydrate as reducing agent by a hydrothermal method. Various parameters that affect on morphology and purity of nanostructures were optimized. According to our experiments the best time and temperature for preparation of this nanostructure are 12 h and 120 °C. The photo-catalytic behaviour of nanostructures in presence of UV-visible light for degradation of methyl orange was investigated. Results show that the presence of UV light is necessary for an efficient degradation of dye in aqueous solution. On the other hand, as observations propose the Ag2Te reveal a strong photoluminescence peak at room temperature that could be attributed to high level transition in the semiconductor. Nanostructures were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared (FT-IR) techniques and UV-visible scanning spectrometer (UV-Vis). PMID:26805744

  10. Molecular modification of coumarin dyes for more efficient dye sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Sánchez-de-Armas, Rocío; San-Miguel, Miguel A.; Oviedo, Jaime; Sanz, Javier Fdez.

    2012-05-01

    In this work, new coumarin based dyes for dye sensitized solar cells (DSSC) have been designed by introducing several substituent groups in different positions of the NKX-2311 structure. Two types of substitutions have been considered: the introduction of three electron-donating groups (-OH, -NH2, and -OCH3) and two different substituents with steric effect: -CH2-CH2-CH2- and -CH2-HC=CH-. The electronic absorption spectra (position and width of the first band and absorption threshold) and the position of the LUMO level related to the conduction band have been used as theoretical criteria to evaluate the efficiency of the new dyes. The introduction of a -NH2 group produces a redshift of the absorption maximum position and the absorption threshold, which could improve the cell efficiency. In contrast, the introduction of -CH2-CH2-CH2- does not modify significantly the electronic structure of NKX-2311, but it might prevent aggregation. Finally, -CH2-HC=CH- produces important changes both in the electronic spectrum and in the electronic structure of the dye, and it would be expected as an improvement of cell efficiency for these dyes.

  11. Molecular modification of coumarin dyes for more efficient dye sensitized solar cells

    SciTech Connect

    Sanchez-de-Armas, Rocio; San-Miguel, Miguel A.; Oviedo, Jaime; Sanz, Javier Fdez.

    2012-05-21

    In this work, new coumarin based dyes for dye sensitized solar cells (DSSC) have been designed by introducing several substituent groups in different positions of the NKX-2311 structure. Two types of substitutions have been considered: the introduction of three electron-donating groups (-OH, -NH{sub 2}, and -OCH{sub 3}) and two different substituents with steric effect: -CH{sub 2}-CH{sub 2}-CH{sub 2}- and -CH{sub 2}-HC=CH-. The electronic absorption spectra (position and width of the first band and absorption threshold) and the position of the LUMO level related to the conduction band have been used as theoretical criteria to evaluate the efficiency of the new dyes. The introduction of a -NH{sub 2} group produces a redshift of the absorption maximum position and the absorption threshold, which could improve the cell efficiency. In contrast, the introduction of -CH{sub 2}-CH{sub 2}-CH{sub 2}- does not modify significantly the electronic structure of NKX-2311, but it might prevent aggregation. Finally, -CH{sub 2}-HC=CH- produces important changes both in the electronic spectrum and in the electronic structure of the dye, and it would be expected as an improvement of cell efficiency for these dyes.

  12. Electropolymerization of Uniform Polyaniline Nanorod Arrays on Conducting Oxides as Counter Electrodes in Dye-Sensitized Solar Cells.

    PubMed

    He, Ziming; Liu, Jing; Khoo, Si Yun; Tan, Timothy Thatt Yang

    2016-01-01

    Conventional techniques for the synthesis of oriented polyaniline (PANI) nanostructures are often complex or time consuming. Through an innovative reduced graphene oxide (rGO) modified FTO and a low-potential electropolymerization strategy, the rapid and template-free growth of a highly ordered PANI nanorod array on the FTO substrate is realized. The highly ordered nanostructure of the PANI array leads to a high electrocatalytic activity and chemical stability. The importance of the polymerization potential and rGO surface modification to achieve this nanostructure is revealed. Compared to platinum, the PANI nanorod array exhibits an enhanced performance and stability as counter electrodes in dye-sensitized solar cells, with a 17.6 % enhancement in power conversion efficiency. PMID:26732134

  13. Efficient Dye-Sensitized Solar Cells with Highly Catalytic Pt-Deposited ZnO/FTO Counter Electrode.

    PubMed

    Park, Ji Young; Lee, Jeong Gwan; Yun, Hyeong Jin; Ahn, Kwang-Soon; Lee, Do Kyung; Kim, Jae Hong

    2015-11-01

    The development of novel cathode is essential for developing high performance dye sensitized solar cells (DSSCs). Here, Pt-coated ZnO nanostructures are used as cathodes of DSSCs to increase their photovoltaic performances. The ZnO nanostructures are grown by chemical bath deposition method, and then Pt is deposited on the nanostructured ZnO substrates. The scanning electron microscopy analyses show that nanostrcutrured Pt-deposited ZnO/FTO is well-formed on fluorinated tin oxide (FTO) substrate with yielding high surface area. The increase in the surface area of Pt-deposited ZnO/FTO leads to the high electrochemical kinetics for reduction of I3- to I-. As a result, the optimized Pt-deposited ZnO/FTO cathode shows the high photovoltaic performances of DSSCs about 6.70% of overall power conversion efficiency, which is 52% higher than the DSSCs using typical Pt-deposited FTO cathode. PMID:26726611

  14. Broadband solar absorption enhancement via periodic nanostructuring of electrodes

    PubMed Central

    Adachi, Michael M.; Labelle, André J.; Thon, Susanna M.; Lan, Xinzheng; Hoogland, Sjoerd; Sargent, Edward H.

    2013-01-01

    Solution processed colloidal quantum dot (CQD) solar cells have great potential for large area low-cost photovoltaics. However, light utilization remains low mainly due to the tradeoff between small carrier transport lengths and longer infrared photon absorption lengths. Here, we demonstrate a bottom-illuminated periodic nanostructured CQD solar cell that enhances broadband absorption without compromising charge extraction efficiency of the device. We use finite difference time domain (FDTD) simulations to study the nanostructure for implementation in a realistic device and then build proof-of-concept nanostructured solar cells, which exhibit a broadband absorption enhancement over the wavelength range of λ = 600 to 1100 nm, leading to a 31% improvement in overall short-circuit current density compared to a planar device containing an approximately equal volume of active material. Remarkably, the improved current density is achieved using a light-absorber volume less than half that typically used in the best planar devices. PMID:24121519

  15. Plasmonic nanoparticles enhanced dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Xu, Qi; Liu, Fang; Meng, Weisi; Huang, Yidong

    2013-12-01

    Here we present investigations on utilizing two kinds of plasmonic nanoparticles (NPs) to enhance the efficiency of dye sensitized solar cells (DSCs). The Au@PVP NPs is proposed and present the specialty of adhesiveness to dye molecules, which could help to localize additional dye molecules near the plasmonic NPs, hence increasing the optical absorption consequently the power conversion efficiency (PCE) of the DSCs by 30% from 3.3% to 4.3%. Meanwhile, an irregular Au-Ag alloy popcorn-shaped NPs (popcorn NPs) with plenty of fine structures is also proposed and realized to enhance the light absorption of DSC. A pronounced absorption enhancement in a broadband wavelength range is observed due to the excitation of localized surface plasmon at different wavelengths. The PCE is enhanced by 32% from 5.94% to 7.85%.

  16. Photodynamic activity of nanostructured fabrics grafted with xanthene and thiazine dyes against opportunistic fungi.

    PubMed

    Kim, Joo Ran; Michielsen, Stephen

    2015-09-01

    Fungi are an important class of human pathogens for which considerable research has gone into defeating them. The photodynamic effects of rose bengal (RB), phloxine B (PB), azure A (AA), and toluidine blue O (TBO) dyes to inhibit Aspergillus fumigatus, Aspergillus niger, Trichoderma viride, Penicillium funiculosum, and Chaetomium globosum were investigated grafted to nano- and micro-structured fabrics. Three antifungal tests conducted: broth microdilution test of free dyes, zone of inhibition and quantitative antifungal assays on fabrics grafted with dyes. In the broth microdilution test, free RB displayed the lowest MIC at 32 μM to inhibit visible hyphal growth and germination but the antifungal ability of MIC for other photosensitizers below 63 μM was insignificant. RB and PB showed lower MIC than AA and TBO. In the inhibition zone tests, nanostructured fabrics grafted with RB and PB did not display fungal growth on the surface. Most microstructured fabrics grafted with AA and TBO showed little inhibition. In quantitative antifungal assay, nanostructured fabrics grafted with RB has the largest inhibition rate on T. viride and the lowest inhibition rate on P. funiculosum and the results showed the increasing inhibition rate in the order of AA < TBO < PB < RB. PMID:25972050

  17. Solar energy conversion with tunable plasmonic nanostructures for thermoelectric devices.

    PubMed

    Xiong, Yujie; Long, Ran; Liu, Dong; Zhong, Xiaolan; Wang, Chengming; Li, Zhi-Yuan; Xie, Yi

    2012-08-01

    The photothermal effect in localized surface plasmon resonance (LSPR) should be fully utilized when integrating plasmonics into solar technologies for improved light absorption. In this communication, we demonstrate that the photothermal effect of silver nanostructures can provide a heat source for thermoelectric devices for the first time. The plasmonic band of silver nanostructures can be facilely manoeuvred by tailoring their shapes, enabling them to interact with photons in different spectral ranges for the efficient utilization of solar light. It is anticipated that this concept can be extended to design a photovoltaic-thermoelectric tandem cell structure with plasmonics as mediation for light harvesting. PMID:22614804

  18. Preparation of Nanoporous TiO2 for Dye-Sensitized Solar Cell (DSSC) Using Various Dyes

    NASA Astrophysics Data System (ADS)

    Yuliarto, Brian; Fanani, Fahiem; Fuadi, M. Kasyful; Nugraha

    2010-10-01

    This article reports the development of organic dyes as an attempt to reduce material costs of Dye-Sensitized Solar Cell (DSSC). Indonesia, a country with variety and considerable number of botanical resources, is suitable to perform the research. Indonesian black rice, curcuma, papaya leaf, and the combination were chosen as organic dyes source. Dyes were extracted using organic solvent and adsorbed on mesoporous Titanium Dioxide (TiO2) which has been optimized in our laboratory. The best dyes light absorbance and performance obtained from papaya leaf as chlorophyll dyes that gives two peaks at 432 nm and 664 nm from UV-Vis Spectrophotometry and performance under 100 mW/cm2 Xenon light solar simulator gives VOC = 0.566 Volt, JSC = 0.24 mA/cm2, Fill Factor = 0.33, and efficiency of energy conversion 0,045%.

  19. Improved Electrodes and Electrolytes for Dye-Based Solar Cells

    SciTech Connect

    Harry R. Allcock; Thomas E. Mallouk; Mark W. Horn

    2011-10-26

    The most important factor in limiting the stability of dye-sensitized solar cells is the use of volatile liquid solvents in the electrolytes, which causes leakage during extended operation especially at elevated temperatures. This, together with the necessary complex sealing of the cells, seriously hampers the industrial-scale manufacturing and commercialization feasibilities of DSSCs. The objective of this program was to bring about a significant improvement in the performance and longevity of dye-based solar cells leading to commercialization. This had been studied in two ways first through development of low volatility solid, gel or liquid electrolytes, second through design and fabrication of TiO2 sculptured thin film electrodes.

  20. Salicylic Acid-Based Organic Dyes Acting as the Photosensitizer for Solar Cells.

    PubMed

    Hong, Sungjun; Park, Jae-Hyeong; Han, Ah-Reum; Ko, Kwan-Woo; Eom, Jin Hee; Namgoong, Sung Keon; Lo, Alvie S V; Gordon, Keith C; Yoon, Sungho; Han, Chi-Hwan

    2016-05-01

    A D-π-A metal-free organic dye, featuring salicylic acid as a novel acceptor/anchoring unit, has been designed, synthesized and applied to dye-sensitized solar cell. The detailed photophysical, electrochemical, photovoltaic and sensitizing properties of the organic dye were investigated, in addition to the computational studies of the dye and dye-(TiO2)6 system. A solar cell device using this new organic dye as a sensitizer produced a solar to electric power conversion efficiency (PCE) of 3.49% (J(sc) = 6.69 mAcm-2, V(oc) = 0.74 V and ff = 0.70) under 100 mWcm(-2) simulated AM 1.5 G solar irradiation, demonstrating that the salicylic acid-based organic dye is a suitable alternative to currently used organometallic dyes. PMID:27483839

  1. Light collection optimization for composite photoanode in dye-sensitized solar cells: Towards higher efficiency

    SciTech Connect

    Guo, X. Z.; Shen, W. Z.

    2015-06-14

    Composite photoanode comprising nanoparticles and one-dimensional (1D) nanostructure is a promising alternative to conventional photoanode for dye-sensitized solar cells (DSCs). Besides fast electron transport channels, the 1D nanostructure also plays as light scattering centers. Here, we theoretically investigate the light scattering properties of capsule-shaped 1D nanostructure and their influence on the light collection of DSCs. It is found that the far-field light scattering of a single capsule depends on its volume, shape, and orientation: capsules with bigger equivalent spherical diameter, smaller aspect ratio, and horizontal orientation demonstrate stronger light scattering especially at large scattering angle. Using Monte Carlo approach, we simulated and optimized the light harvesting efficiency of the cell. Two multilayer composite photoanodes containing orderly or randomly oriented capsules are proposed. DSCs composed of these two photoanodes are promising for higher efficiencies because of their efficient light collection and superior electron collection. These results will provide practical guidance to the design and optimization of the photoanodes for DSCs.

  2. The generalized Shockley-Queisser limit for nanostructured solar cells

    PubMed Central

    Xu, Yunlu; Gong, Tao; Munday, Jeremy N.

    2015-01-01

    The Shockley-Queisser limit describes the maximum solar energy conversion efficiency achievable for a particular material and is the standard by which new photovoltaic technologies are compared. This limit is based on the principle of detailed balance, which equates the photon flux into a device to the particle flux (photons or electrons) out of that device. Nanostructured solar cells represent a novel class of photovoltaic devices, and questions have been raised about whether or not they can exceed the Shockley-Queisser limit. Here we show that single-junction nanostructured solar cells have a theoretical maximum efficiency of ∼42% under AM 1.5 solar illumination. While this exceeds the efficiency of a non-concentrating planar device, it does not exceed the Shockley-Queisser limit for a planar device with optical concentration. We consider the effect of diffuse illumination and find that with optical concentration from the nanostructures of only × 1,000, an efficiency of 35.5% is achievable even with 25% diffuse illumination. We conclude that nanostructured solar cells offer an important route towards higher efficiency photovoltaic devices through a built-in optical concentration. PMID:26329479

  3. Ag nanoparticle-deposited TiO2 nanotube arrays for electrodes of Dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Kawamura, Go; Ohmi, Hayato; Tan, Wai Kian; Lockman, Zainovia; Muto, Hiroyuki; Matsuda, Atsunori

    2015-05-01

    Dye-sensitized solar cells composed of a photoanode of Ag nanoparticle (NP)-deposited TiO2 nanotube (TNT) arrays were fabricated. The TNT arrays were prepared by anodizing Ti films on fluorine-doped tin oxide (FTO)-coated glass substrates. Efficient charge transportation through the ordered nanostructure of TNT arrays should be carried out compared to conventional particulate TiO2 electrodes. However, it has been a big challenge to grow TNT arrays on FTO glass substrates with the lengths needed for sufficient light-harvesting (tens of micrometers). In this work, we deposited Ag nanoparticles (NPs) on the wall of TNT arrays to enhance light-harvesting property. Dye-sensitized solar cells with these Ag NP-deposited TNT arrays yielded a higher power conversion efficiency (2.03 %) than those without Ag NPs (1.39 %).

  4. The Structure-property Relationships of D-π-A BODIPY Dyes for Dye-sensitized Solar Cells.

    PubMed

    Mao, Mao; Song, Qin-Hua

    2016-04-01

    BODIPY dyes have attracted considerable attention as potential photosensitizers in dye-sensitized solar cells (DSSCs) owing to their excellent optical properties and facile structural modification. This account focuses on recent advances in the molecular design of D-π-A BODIPY dyes for applications in DSSCs. Special attention has been paid to the structure-property relationships of D-π-A BODIPY dyes for DSSCs. The developmental process in the modified position at the BODIPY core with a donor/acceptor is described. The devices based on 2,6-modified BODIPY dyes exhibit better photovoltaic performance over other modified BODIPY dyes. Meanwhile, the research reveals the correlation of molecular structures (various donor chromophores, extended units, molecular frameworks, and long alkyl groups) with their photophysical and electrochemical properties and relates it to their performance in DSSCs. The structure-property relationships give valuable information and guidelines for designing new D-π-A BODIPY dyes for DSSCs. PMID:26846846

  5. Dye-Sensitized Solar Cells for Space Power

    NASA Technical Reports Server (NTRS)

    Harris, Jerry D.; Hehemann, David G.; Duraj, Stan A.

    2003-01-01

    During the course of this grant, dye-sensitized solar cells were prepared and characterized. The solar cells were prepared using materials (dyes, electrolytes, transparent conductive oxide coated glass, nanocrystalline TiO2) entirely prepared in-house, as well as prepared using materials available commercially. Complete cells were characterized under simulated AM0 illumination. The best cell prepared at NASA had an AM0 efficiency of 1.22% for a 1.1 sq cm cell. Short circuit current (Isc), open circuit voltage (Voc) and fill factor (FF) for the cell were 6.95 mA, 618 mV and 42.8%, respectively. For comparison purposes, two commercially prepared dye-sensitized solar cells were obtained from Solaronix SA, Aubonne, Switzerland. The Solaronix cells were also characterized under simulated AM0 illumination. The best cell from Solaronix had an active area of 3.71 sq cm and measured an AM0 efficiency of 3.16%. with Isc, Voc and FF of 45.80 mA, 669.6 mV and 52.3%, respectively. Both cells from Solaronix were rapid thermal cycled between -80 C and 80 C. Thermal cycling led to a 4.6% loss of efficiency in one of the cells and led to nearly a complete failure in the second cell.

  6. Dye-sensitized solar cells using laser processing techniques

    NASA Astrophysics Data System (ADS)

    Kim, Heungsoo; Pique, Alberto; Kushto, Gary P.; Auyeung, Raymond C. Y.; Lee, S. H.; Arnold, Craig B.; Kafafi, Zakia H.

    2004-07-01

    Laser processing techniques, such as laser direct-write (LDW) and laser sintering, have been used to deposit mesoporous nanocrystalline TiO2 (nc-TiO2) films for use in dye-sensitized solar cells. LDW enables the fabrication of conformal structures containing metals, ceramics, polymers and composites on rigid and flexible substrates without the use of masks or additional patterning techniques. The transferred material maintains a porous, high surface area structure that is ideally suited for dye-sensitized solar cells. In this experiment, a pulsed UV laser (355nm) is used to forward transfer a paste of commercial TiO2 nanopowder (P25) onto transparent conducting electrodes on flexible polyethyleneterephthalate (PET) and rigid glass substrates. For the cells based on flexible PET substrates, the transferred TiO2 layers were sintered using an in-situ laser to improve electron paths without damaging PET substrates. In this paper, we demonstrate the use of laser processing techniques to produce nc-TiO2 films (~10 μm thickness) on glass for use in dye-sensitized solar cells (Voc = 690 mV, Jsc = 8.7 mA/cm2, ff = 0.67, η = 4.0 % at 100 mW/cm2). This work was supported by the Office of Naval Research.

  7. Novel energy relay dyes for high efficiency dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Rahman, Md. Mahbubur; Ko, Min Jae; Lee, Jae-Joon

    2015-02-01

    4',6-Diamidino-2-phenylindole (DAPI) and Hoechst 33342 (H33342) were used as novel energy relay dyes (ERDs) for an efficient energy transfer to the N719 dye in I-/I3- based liquid-junction dye-sensitized solar cells (DSSCs). The introduction of the ERDs, either as an additive in the electrolyte or as a co-adsorbent, greatly enhanced the power conversion efficiencies (PCEs), mainly because of an increase in short-circuit current density (Jsc). This was attributed to the effects of non-radiative Förster-type excitation energy transfer as well as the radiative (emission)-type fluorescent energy transfer to the sensitizers. The net PCEs for the N719-sensitized DSSCs with DAPI and H33342 were 10.65% and 10.57%, and showed an improvement of 12.2% and 11.4% over control devices, respectively.4',6-Diamidino-2-phenylindole (DAPI) and Hoechst 33342 (H33342) were used as novel energy relay dyes (ERDs) for an efficient energy transfer to the N719 dye in I-/I3- based liquid-junction dye-sensitized solar cells (DSSCs). The introduction of the ERDs, either as an additive in the electrolyte or as a co-adsorbent, greatly enhanced the power conversion efficiencies (PCEs), mainly because of an increase in short-circuit current density (Jsc). This was attributed to the effects of non-radiative Förster-type excitation energy transfer as well as the radiative (emission)-type fluorescent energy transfer to the sensitizers. The net PCEs for the N719-sensitized DSSCs with DAPI and H33342 were 10.65% and 10.57%, and showed an improvement of 12.2% and 11.4% over control devices, respectively. Electronic supplementary information (ESI) available: Details of the materials and instrumentation, device fabrication, measurement and calculations of the quantum yield (Qd), calculations of the Förster radius (R0), optimization of the ERDs mixed with electrolyte according to Type-A strategy; normalized absorption profiles of the N3, Ru505, and Z907 dyes and the emission profiles of DAPI and H33342

  8. Circle chain embracing donor-acceptor organic dye: simultaneous improvement of photocurrent and photovoltage for dye-sensitized solar cells.

    PubMed

    Liu, Jian; Numata, Youhei; Qin, Chuanjiang; Islam, Ashraful; Yang, Xudong; Han, Liyuan

    2013-09-01

    We demonstrate for the first time that employing a circle chain embracing π-conjugated backbone is a promising strategy to construct superior organic sensitizers for dye-sensitized solar cells (DSCs), with simultaneous improvement of photocurrent and photovoltage. A DSC based on one circle chain embracing dye produced a high conversion efficiency of 8.34%. PMID:23604204

  9. First principles modeling of panchromatic dyes for solar cells applications.

    NASA Astrophysics Data System (ADS)

    di Felice, Rosa; Calzolari, Arrigo; Dong, Rui; Buongiorno Nardelli, Marco

    2013-03-01

    The state-of-the-art dye in Grätzel solar cells, N719, exhibits a total solar-to-electric conversion efficiency of 11.2%. However, it severely lacks absorption in the red and the near infrared regions of the electromagnetic spectrum, which represent more than 70% of the solar radiation spectrum. Using calculations from first principles in the time-dependent domain, we have studied the electronic and optical response of a novel class of panchromatic sensitizers that can harvest solar energy efficiently across the visible and near infrared regions, which have been recently synthesized [A. El-Shafei, M. Hussain, A. Atiq, A. Islam, and L. Han, J. Mater. Chem. 22, 24048 (2012)]. Our calculations show that, by tuning the properties of antenna groups, one can achieve a substantial improvement of the optical properties.

  10. Ultrafast carrier dynamics in nanostructures for solar fuels.

    PubMed

    Baxter, Jason B; Richter, Christiaan; Schmuttenmaer, Charles A

    2014-01-01

    Sunlight can be used to drive chemical reactions to produce fuels that store energy in chemical bonds. These fuels, such as hydrogen from splitting water, have much larger energy density than do electrical storage devices. The efficient conversion of clean, sustainable solar energy using photoelectrochemical and photocatalytic systems requires precise control over the thermodynamics, kinetics, and structural aspects of materials and molecules. Generation, thermalization, trapping, interfacial transfer, and recombination of photoexcited charge carriers often occur on femtosecond to picosecond timescales. These short timescales limit the transport of photoexcited carriers to nanometer-scale distances, but nanostructures with high surface-to-volume ratios can enable both significant light absorption and high quantum efficiency. This review highlights the importance of understanding ultrafast carrier dynamics for the generation of solar fuels, including case studies on colloidal nanostructures, nanostructured photoelectrodes, and photoelectrodes sensitized with molecular chromophores and catalysts. PMID:24423371

  11. Array of titanium dioxide nanostructures for solar energy utilization

    DOEpatents

    Qiu, Xiaofeng; Parans Paranthaman, Mariappan; Chi, Miaofang; Ivanov, Ilia N; Zhang, Zhenyu

    2014-12-30

    An array of titanium dioxide nanostructures for solar energy utilization includes a plurality of nanotubes, each nanotube including an outer layer coaxial with an inner layer, where the inner layer comprises p-type titanium dioxide and the outer layer comprises n-type titanium dioxide. An interface between the inner layer and the outer layer defines a p-n junction.

  12. Comparison of Dye-Sensitized Rutile- and Anatase-Based TiO2 Solar Cells

    SciTech Connect

    Park, N. G.; van de Lagemaat, J.; Frank, A. J.

    2000-01-01

    The objective of this work is to develop and optimize the new dye-sensitized solar cell technology. In view of the infancy of rutile material development for solar cells, the PV response of the dye-sensitized rutile-based solar cell is remarkably close to that of the anatase-based cell.

  13. Screening π-conjugated bridges of organic dyes for dye-sensitized solar cells with panchromatic visible light harvesting.

    PubMed

    Yang, Zhenqing; Liu, Chunmeng; Shao, Changjin; Zeng, Xiaofei; Cao, Dapeng

    2016-07-01

    Developing highly efficient organic dyes with panchromatic visible light harvesting for dye-sensitized solar cells (DSSCs) is still one of the most important scientific challenges. Here, we design a series of phenothiazine derivative organic dyes with donor-π-acceptor (D-π-A) structure using density functional theory (DFT) and time-dependent DFT (TDDFT) based on experimentally synthesized typical SH-6 organic dyes. Results indicate that the newly designed BUCT13 - BUCT30 dyes show smaller HOMO-LUMO energy gaps, higher molar extinction coefficients and obvious redshifts compared to the SH-6 dye, and the maximum absorption peaks of eight dyes are greater than 650 nm among the newly designed dyes. In particular, BUCT27 exhibits a 234 nm redshift and the maximum molar extinction coefficient with an increment of about 80% compared to the SH-6 dye. BUCT19 exhibits not only a 269 nm redshift and higher molar extinction coefficient with an increment of about 50% compared to the SH-6 dye, but the extremely broad absorption spectrum covering the entire visible range up to the near-IR region of 1200 nm. It is expected that this work can provide a new strategy and guidance for the investigation of these dye-sensitized devices. PMID:27188528

  14. Screening π-conjugated bridges of organic dyes for dye-sensitized solar cells with panchromatic visible light harvesting

    NASA Astrophysics Data System (ADS)

    Yang, Zhenqing; Liu, Chunmeng; Shao, Changjin; Zeng, Xiaofei; Cao, Dapeng

    2016-07-01

    Developing highly efficient organic dyes with panchromatic visible light harvesting for dye-sensitized solar cells (DSSCs) is still one of the most important scientific challenges. Here, we design a series of phenothiazine derivative organic dyes with donor–π–acceptor (D–π–A) structure using density functional theory (DFT) and time-dependent DFT (TDDFT) based on experimentally synthesized typical SH-6 organic dyes. Results indicate that the newly designed BUCT13 – BUCT30 dyes show smaller HOMO–LUMO energy gaps, higher molar extinction coefficients and obvious redshifts compared to the SH-6 dye, and the maximum absorption peaks of eight dyes are greater than 650 nm among the newly designed dyes. In particular, BUCT27 exhibits a 234 nm redshift and the maximum molar extinction coefficient with an increment of about 80% compared to the SH-6 dye. BUCT19 exhibits not only a 269 nm redshift and higher molar extinction coefficient with an increment of about 50% compared to the SH-6 dye, but the extremely broad absorption spectrum covering the entire visible range up to the near-IR region of 1200 nm. It is expected that this work can provide a new strategy and guidance for the investigation of these dye-sensitized devices.

  15. Nature of photovoltaic action in dye-sensitized solar cells

    SciTech Connect

    Cahen, D.; Hodes, G.; Graetzel, M.; Guillemoles, J.F.; Riess, I.

    2000-03-09

    The authors explain the cause for the photocurrent and photovoltage in nanocrystalline, mesoporous dye-sensitized solar cells, in terms of the separation, recombination, and transport of electronic charge as well as in terms of electron energetics. On the basis of available experimental data, the basic cause for the photovoltage was confirmed as the change in the electron concentration in the nanocrystalline electron conductor that results from photoinduced charge injection from the dye. The maximum photovoltage is given by the difference in electron energies between the redox level and the bottom of the electron conductor's conduction band, rather than by any difference in electrical potential in the cell, in the dark. Charge separation occurs because of the energetic and entropic driving forces that exist at the dye/electron conductor interface, with charge transport aided by such driving forces at the electron conductor-contact interface. The mesoporosity and nanocrystallinity of the semiconductor are important not only because of the large amount of dye that can be adsorbed on the system's very large surface, but also for two additional reasons: (1) it allows the semiconductor small particles to become almost totally depleted upon immersion in the electrolyte (allowing for large photovoltages), and (2) the proximity of the electrolyte to all particles modes screening of injected electrons, and thus their transport, possible.

  16. Quasi Solid Polymer Electrolytes for Dye Sensitized Solar Cells

    NASA Astrophysics Data System (ADS)

    Dissanayake, M. A. K. Lakshman

    2013-07-01

    Dye-sensitized solar cell (DSSC) has been considered as an alternative to the conventional silicon solar cell because of low cost, easy fabrication and relatively high conversion efficiency. A DSSC consists of a dye-sensitized nanoparticulated TiO2 electrode, an electrolyte containing redox couple and a Pt coated counter electrode. Such solar cells based on an I-/I3- redox couple in an organic solvent usually have conversion efficiencies reaching around 11%. However, a major drawback of these solution based solar cells, originally developed by Gratzel and coworkers is the lack of long-term stability due to liquid leakage, usage of volatile liquids such as acetonitrile, electrode corrosion, and photodecomposition of the dye in the solvent medium. Therefore considerable research efforts have been made in recent years to replace the liquid electrolytes with solid polymer or quasi-solid polymer (gel) electrolytes. Among these approaches, the use of gel polymer electrolytes appears to give rise to successful results in terms of conversion efficiency. Conventional poly (ethylene oxide)(PEO)-based solid polymer electrolytes exhibit poor ionic conductivities at room temperature, which is not sufficient for practical applications. Therefore, most of the recent studies have been directed to the preparation and characterization of gel polymer electrolytes which exhibit higher ionic conductivity at ambient temperature while maintain quai-solid structure. These gel polymer electrolytes prepared by incorporating a liquid electrolyte into a matrix polymer such as polyacrylonitrile(PAN), poly(vinylidene fluoride)(PVdF), poly (methyl methacrylate) (PMMA) and PEO have been employed in quasi-solid-state DSSCs to achieve power conversion efficiencies of more than 5%. Significant improvements have been achieved in recent years by modifications of the electrolytes by optimizing the ionic salt, introducing additives such as inorganic nanofillers, organic molecules and ionic liquids in

  17. Performance of Caesalpinia sappan heartwood extract as photo sensitizer for dye sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Ananth, S.; Vivek, P.; Saravana Kumar, G.; Murugakoothan, P.

    2015-02-01

    A natural dye extracted from Caesalpinia sappan heartwood was used as photo sensitizer for the first time to fabricate titanium dioxide (TiO2) nanoparticles based dye sensitized solar cells. Brazilin and brazilein are the major pigments present in the natural dye and their optimized molecular structure were calculated using Density functional theory (DFT) at 6-31G (d) level. The HOMO-LUMO were performed to reveal the energy gap using optimized structure. Pure TiO2 nanoparticles in anatase phase were synthesized by sol-gel technique. The pure and natural dye sensitized TiO2 nanoparticles were subjected to structural, optical, spectral and morphological studies. Low cost and environment friendly dye sensitized solar cells were fabricated using natural dye sensitized TiO2 based photo anode. The solar light to electron conversion efficiency of Caesalpinia sappan heartwood extract sensitized dye sensitized solar cell is 1.1%.

  18. Asymmetric Zinc Phthalocyanines as Dye-Sensitized Solar Cells

    NASA Astrophysics Data System (ADS)

    Tunc, Gulenay; Yavuz, Yunus; Gurek, Aysegul; Canimkurbey, Betul; Kosemen, Arif; San, Sait Eren; Ahsen, Vefa

    Dye-sensitized solar cells (DSSCs) have received increasing attention due to their high incident to photon efficiency, easy fabrication and low production cost . Tremendous research efforts have been devoted to the development of new and efficient sensitizers suitable for practical use. In TiO2-based DSSCs, efficiencies of up to 11.4% under simulated sunlight have been obtained with rutheniumepolypyridyl complexes. However, the main drawback of ruthenium complexes is the lack of absorption in the red region of the visible light and the high cost. For this reason, dyes with large and stable p-conjugated systems such as porphyrins and phthalocyanines are important classes of potential sensitizers for highly efficient DSSCs. Phthalocyanines (Pcs) have been widely used as sensitizers because of their improved light-harvesting properties in the far red- and near-IR spectral regions and their extraordinary robustness [1]. In this work, a series of asymmetric Zn(II) Pcs bearing a carboxylic acid group and six hexylthia groups either at the peripheral or non-peripheral positions have been designed and synthesized to investigate the influence of the COOH group and the positions of hexylthia groups on the dye-sensitized solar cell (DSSC) performance.

  19. Direct Blue Dye Degradation Using Titanium Nanostructures Under Energy-Efficient UV-LED Irradiation

    NASA Astrophysics Data System (ADS)

    Jo, Wan-Kuen; Tayade, Rajesh J.

    2016-01-01

    The present study describes the effect of titanium dioxide (TiO2) morphology on the photocatalytic activity under irradiation of ultraviolet light-emitting diode (UV-LED). Different TiO2 nanostructures were synthesized using hydrothermal (nanotubes and nanospheres) and solvothermal (nanoflowers) methods. The morphology, phase composition, bandgap, and chemical properties of the synthesized different TiO2 nanostructures were characterized using x-ray diffraction, scanning electron microscopy, transmission electron microscopy, ultraviolet visible diffuse reflectance spectroscopy (UV-Vis DRS), and Brunauer-Emmett-Teller (BET) analysis. The surface area of the nanotubes was larger than that of the nanospheres and nanoflowers by four- and three-fold, respectively. The photocatalytic activity of the photocatalysts was evaluated by degradation of direct blue-15 dye under UV-LED irradiation in a slurry-type reactor. The photocatalytic activity of the TiO2 nanoflowers was higher than that of TiO2 nanotubes or nanospheres, suggesting that nanoflowers can serve as efficient photocatalysts for dye degradation.

  20. Modeling of the dye loading time influence on the electrical impedance of a dye-sensitized solar cell

    NASA Astrophysics Data System (ADS)

    Pugliese, D.; Shahzad, N.; Sacco, A.; Tresso, E.; Alexe-Ionescu, A. L.

    2013-09-01

    A hemisquaraine dye molecule (CT1) was used as TiO2 sensitizer. The influence of the dye-adsorption time on the electrical impedance of a CT1-based dye-sensitized solar cell (DSC) was analyzed. Differently from what we observed with commercial Ru dye-based DSC, a non-monotonic effect of the impregnation time on the impedance has been found and the dye loading time is much reduced, a desirable outcome in economic grounds. This feature is analyzed in terms of the dye molecules tendency to aggregate close to the TiO2/electrolyte interface. A physical model that fits well the experimental data is proposed, which also takes into account a correction related to the difference between the illuminated area of the cell and the total area available in the electrical measurements.

  1. Ruthenium phthalocyanine-bipyridyl dyads as sensitizers for dye-sensitized solar cells: dye coverage versus molecular efficiency.

    PubMed

    Rawling, Tristan; Austin, Christine; Buchholz, Florian; Colbran, Stephen B; McDonagh, Andrew M

    2009-04-01

    The application of ruthenium phthalocyanine complexes as sensitizing dyes in dye-sensitized solar cells (DSCs) is explored. Four monomeric complexes are reported which vary in peripheral substitution and axial ligand anchoring groups. Sensitizing dyes containing two ruthenium centers are also presented. These dyads, which contain ruthenium phthalocyanine and bipyridyl chromophores, were prepared using a protection/deprotection strategy that allows for convenient purification. DSCs fabricated using the phthalocyanine complexes and dyads were less efficient than those incorporating a standard DSC dye. However, on the basis of the number of molecules bound to the TiO(2) electrode surfaces, several of the new complexes were more efficient at photocurrent generation. The results highlight the importance of molecular size, and thus the dye coverage of the electrode surface in the design of new sensitizing dyes. PMID:19278209

  2. Benzotriazole-based dyes containing a low band gap for dye-sensitised solar cells: a theoretical study

    NASA Astrophysics Data System (ADS)

    Karthikeyan, S.; Lee, Jin Yong

    2014-12-01

    In this study, we investigated a series of metal-free benzotriazole-based organic dyes. The geometries, electronic properties, light harvesting efficiency, and electronic absorption spectra of these dyes were studied using the density functional theory and time-dependent density functional theory. The optimised geometries indicate that these dyes are non-planar and thereby effectively inhibit close intermolecular π-π aggregation. The band gap of these dyes ensures a positive effect on the process of electron injection and dye regeneration. The band gap trend corroborates well with the predicted spectra data. Our theoretical calculations reveal that the designed metal-free organic dyes can be used as potential sensitisers for solar cells compared to the best known organic sensitiser (Y123) to date.

  3. Natural dye -sensitized mesoporous ZnO solar cell

    NASA Astrophysics Data System (ADS)

    Wu, Qishuang; Shen, Yue; Wu, Guizhi; Li, Linyu; Cao, Meng; Gu, Feng

    2010-10-01

    Natural dye-sensitized solar cells (N-DSSCs) were assembled using chlorophyll sensitized mesoporous ZnO (based on FTO) as the photoanode and platinum plate as the cathode. The natural dyes (chlorophyll) were extracted from spinach by simple procedure. The absorption spectrum and fluorescence spectrum of chlorophyll were studied. Mesoporous ZnO (m-ZnO) applied to the N-DSSCs was synthesized through hydrothermal method. The structures and morphologies were characterized by X-ray Diffraction (XRD) and diffuse reflection. The results indicated that the samples had an average pore size of 17 nm and the m-ZnO was hexagonal wurtzite structure. The performances of the N-DSSCs were investigated under AM 1.5G illumination. The Voc of the N-DSSCs was about 480mv, and the Isc was about 470μA. The performance of the N-DSSCs could be further improved by adjusting its structure.

  4. Natural dye -sensitized mesoporous ZnO solar cell

    NASA Astrophysics Data System (ADS)

    Wu, Qishuang; Shen, Yue; Wu, Guizhi; Li, Linyu; Cao, Meng; Gu, Feng

    2011-02-01

    Natural dye-sensitized solar cells (N-DSSCs) were assembled using chlorophyll sensitized mesoporous ZnO (based on FTO) as the photoanode and platinum plate as the cathode. The natural dyes (chlorophyll) were extracted from spinach by simple procedure. The absorption spectrum and fluorescence spectrum of chlorophyll were studied. Mesoporous ZnO (m-ZnO) applied to the N-DSSCs was synthesized through hydrothermal method. The structures and morphologies were characterized by X-ray Diffraction (XRD) and diffuse reflection. The results indicated that the samples had an average pore size of 17 nm and the m-ZnO was hexagonal wurtzite structure. The performances of the N-DSSCs were investigated under AM 1.5G illumination. The Voc of the N-DSSCs was about 480mv, and the Isc was about 470μA. The performance of the N-DSSCs could be further improved by adjusting its structure.

  5. Concrete Embedded Dye-Synthesized Photovoltaic Solar Cell

    PubMed Central

    Hosseini, T.; Flores-Vivian, I.; Sobolev, K.; Kouklin, N.

    2013-01-01

    This work presents the concept of a monolithic concrete-integrated dye-synthesized photovoltaic solar cell for optical-to-electrical energy conversion and on-site power generation. The transport measurements carried out in the dark revealed the presence of VOC of ~190 mV and ISC of ~9 μA, induced by the electrochemical conversion of concrete-supplied ionic impurities at the electrodes. The current-voltage measurements performed under illumination at incident optical powers of ~46 mW confirmed the generation of electrical power of ~0.64 μW with almost half generated via battery effect. This work presents a first step towards realizing the additional pathways to low-cost electrical power production in urban environments based on a combined use of organic dyes, nanotitania and concrete technology. PMID:24067664

  6. Towards low temperature sintering methods for dye sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Murali, Sukanya

    Access to economically viable renewable energy sources is essential for the development of a globally sustainable society. Solar energy has a large potential to satisfy the future need for renewable energy sources. Dye sensitized solar cells are a third generation of photovoltaic technologies with the potential for low cost environmentally safe energy production. Commercialization of this technology requires that dye sensitized solar cells with higher efficiencies can be fabricated on flexible substrates. The commonly used material for the anode in a Dye Sensitized Solar Cell consists of titanium dioxide nanoparticles covered with a layer of light sensitizing dye. For efficient electron transport throughout the nanoparticle network, good particle interconnections are necessary. For low temperature processing these interconnections can be achieved through a hydrothermal process. The focus of this research is to understand at a fundamental level this reaction-based sintering process. A titanium alkoxide precursor was mixed with commercial titania nanoparticles and coated on a transparent conductive oxide substrate. The product of the hydrolysis and condensation of the alkoxide served to connect the nanoparticles thus improving the electrical conduction of the titania electrode; this was confirmed by solar cell testing and electrochemical impedance spectroscopy. To further understand the formation of interconnections during reactive sintering, a model system based on inert silica particles was investigated. Titanium alkoxide precursor was mixed with commercial silica particles and reacted. Three different types of silica particles were used: each with a different morphology. The silica-titania multilayers/powders were characterized using SEM, XRD and BET. The efficiency of DSSCs is higher when larger non-porous silica particles are used and thin nanocrystalline titania is coated on this superstructure. This gave insight into the locations where the reactive liquid

  7. Multifunctional Interface Modification of Energy Relay Dye in Quasi-solid Dye-sensitized Solar Cells

    PubMed Central

    Gao, Rui; Cui, Yixiu; Liu, Xiaojiang; Wang, Liduo

    2014-01-01

    In this paper, 4-(dicyanomethylene)-2-t-butyl-6(1,1,7,7-tetramethyljulolidyl-9-enyl)-4H-pyran (DCJTB) has been used in interface modification of dye-sensitized solar cells (DSCs) with combined effects of retarding charge recombination and Förster resonant energy transfer (FRET). DCJTB interface modification significantly improved photovoltaic performance of DSCs. I–V curves shows the conversion efficiency increases from 4.27% to 5.64% with DCJTB coating. The application of DCJTB with combined effects is beneficial to explore more novel multi-functional interface modification materials to improve the performance of DSCs. PMID:24993900

  8. Scanning photo-electrochemical microscopy as a versatile tool to investigate dye-sensitized nano-crystalline surfaces for solar cells

    NASA Astrophysics Data System (ADS)

    Figgemeier, Egbert; Kylberg, William H.; Bozic, Biljana

    2006-04-01

    Self-assembled monolayers (SAMs) of metal complexes are a central component of functional chemical systems for energy conversion like in e.g. the dye-sensitized photoelectrochemical solar cells or photocatalytic processes at semiconductor surfaces. In this context, scanning electrochemical microscopy (SECM) under illumination is a most valuable tool for the understanding of elementary processes of such systems. SECM comprises an ultra-microelectrode (UME), which is incorporated into a 3- or 4-electrode, respectively, electrochemical setup and which can be positioned with sub-micrometer resolution in 3 dimensions relative to a substrate. In our system, we used Pt-UMEs and dye-sensitized nano-structured electrodes as substrates. The substrate can be illuminated from the backside, which resembles working conditions of solar cell arrangements. The electrolyte consists of 2-methoxypropionitrile in conjunction with redox couples as they are used in dye-sensitized nano-structured solar cell. With this setup the photoelectrochemistry in close contact to the substrate surface initiated by the injection of electrons from the dye into the conduction band of the TiO II due to illumination at working conditions has been investigated. In this contribution we present the general principle of the method as well as an initial validation by relating photocurrents measured with the SECM and solar cell performances.

  9. Parallel Tandems of Dye Sensitized Solar Cells with CNT Collector

    NASA Astrophysics Data System (ADS)

    Velten, Josef; Yuan, Chao-Chen; Zakhidov, Anvar

    2009-03-01

    In this presentation, we demonstrate the fabrication of monolithic parallel tandem dye sensitized solar cells using a semitransparent layer of carbon nanotubes. Each DSC sub-cell has titania photoelectrode with two different dyes: N 719 and N 749, which absorb light in different parts of solar spectrum. This layer of carbon nanotubes laminated on highly porous polymeric Millipore filter acts as both the collector of charge carrier and as the catalyst of the I/I3^- redox reaction that completes the function of the cell, overall allowing easier fabrication for tandem solar cell devices, with a potential for creating flexible devices in the future. The parallel tandem shows the total photocurrent which is nearly the sum of two Isc currents of constituent cells, and total Voc, which is average of two Voc, while conventional in-series DSC tandems show the lowest Voc and slightly increased Isc[1]. Thus the higher efficiency can be achieved in parallel DSC tandems, and we discuss the physical reasons for this effect. [1] Yanagida, et.al. J. of Photochemistry and Photobiology A: Chemistry Volume 164, Issues 1-3, 1 June 2004, Pages 33-39

  10. Digital Printing of Titanium Dioxide for Dye Sensitized Solar Cells

    PubMed Central

    Cherrington, Ruth; Wood, Benjamin Michael; Salaoru, Iulia; Goodship, Vannessa

    2016-01-01

    Silicon solar cell manufacturing is an expensive and high energy consuming process. In contrast, dye sensitized solar cell production is less environmentally damaging with lower processing temperatures presenting a viable and low cost alternative to conventional production. This paper further enhances these environmental credentials by evaluating the digital printing and therefore additive production route for these cells. This is achieved here by investigating the formation and performance of a metal oxide photoelectrode using nanoparticle sized titanium dioxide. An ink-jettable material was formulated, characterized and printed with a piezoelectric inkjet head to produce a 2.6 µm thick layer. The resultant printed layer was fabricated into a functioning cell with an active area of 0.25 cm2 and a power conversion efficiency of 3.5%. The binder-free formulation resulted in a reduced processing temperature of 250 °C, compatible with flexible polyamide substrates which are stable up to temperatures of 350 ˚C. The authors are continuing to develop this process route by investigating inkjet printing of other layers within dye sensitized solar cells. PMID:27166761

  11. Digital Printing of Titanium Dioxide for Dye Sensitized Solar Cells.

    PubMed

    Cherrington, Ruth; Wood, Benjamin Michael; Salaoru, Iulia; Goodship, Vannessa

    2016-01-01

    Silicon solar cell manufacturing is an expensive and high energy consuming process. In contrast, dye sensitized solar cell production is less environmentally damaging with lower processing temperatures presenting a viable and low cost alternative to conventional production. This paper further enhances these environmental credentials by evaluating the digital printing and therefore additive production route for these cells. This is achieved here by investigating the formation and performance of a metal oxide photoelectrode using nanoparticle sized titanium dioxide. An ink-jettable material was formulated, characterized and printed with a piezoelectric inkjet head to produce a 2.6 µm thick layer. The resultant printed layer was fabricated into a functioning cell with an active area of 0.25 cm(2) and a power conversion efficiency of 3.5%. The binder-free formulation resulted in a reduced processing temperature of 250 °C, compatible with flexible polyamide substrates which are stable up to temperatures of 350 ˚C. The authors are continuing to develop this process route by investigating inkjet printing of other layers within dye sensitized solar cells. PMID:27166761

  12. Dynamic Characteristics of Aggregation Effects of Organic Dyes in Dye-Sensitized Solar Cells.

    PubMed

    Feng, Shuai; Li, Quan-Song; Sun, Ping-Ping; Niehaus, Thomas A; Li, Ze-Sheng

    2015-10-14

    Two organic dyes (LS-1 and IQ4) containing identical electron donor and acceptor units but distinct π units result in significantly different power conversion efficiency of the corresponding dye-sensitized solar cells (DSSCs): LS-1, 4.4%, and IQ4, 9.2%. Herein, we combine first-principle calculations and molecular dynamics to explore the aggregation effects of LS-1 and IQ4 by comparing their optical properties and intermolecular electronic couplings. The calculated absorption spectra are in good agreement with the experimental observations and reveal them to be evidently affected by the dimerization. Furthermore, molecular dynamics simulations show that steric hindrance induced by the diphenylquinoxaline unit in IQ4 can elongate the distances between intermolecular π units or electron donors, which are responsible for the fact that the intermolecular electronic coupling of LS-1 is about 10 times larger than that of IQ4. More importantly, the aggregated IQ4 remains almost perpendicular to the TiO2 surface, whereas LS-1 gradually tilts during the dynamic simulation, impacting electron injection and recombination in several ways, which clarifies why IQ4 leads to larger photocurrent and higher conversion efficiency. The deep understanding of the dye aggregation effects sheds new light on the complex factors determining DSSC function and paves the way for rational design of high-efficiency self-anti-aggregation sensitizers. PMID:26391331

  13. New architectures for dye-senstized solar cells.

    SciTech Connect

    Martinson, A. B. F.; Hamann, T. W.; Pellin, M. J.; Hupp, J. T.; Materials Science Division; Northwestern Univ.

    2008-01-01

    Modern dye-sensitized solar cell (DSSC) technology was built upon nanoparticle wide bandgap semiconductor photoanodes. While versatile and robust, the sintered nanoparticle architecture exhibits exceedingly slow electron transport that ultimately restricts the diversity of feasible redox mediators. The small collection of suitable mediators limits both our understanding of an intriguing heterogeneous system and the performance of these promising devices. Recently, a number of pseudo-1D photoanodes that exhibit accelerated charge transport and greater materials flexibility were fabricated. The potential of these alternative photoanode architectures for advancing, both directly and indirectly, the performance of DSSCs is explored.

  14. Weavable dye sensitized solar cells exploiting carbon nanotube yarns

    NASA Astrophysics Data System (ADS)

    Velten, Josef; Kuanyshbekova, Zharkynay; Göktepe, Özer; Göktepe, Fatma; Zakhidov, Anvar

    2013-05-01

    Weavable Dye Sensitized Solar Cells (DSSC) made with flexible yarns of conductive multiwalled carbon nanotubes (MWNTs) were produced having a power conversion efficiency above 3%. This was achieved with a specific design and careful consideration of the yarn function in the DSSC. Fermat yarns of MWNTs individually coated with mesoporous TiO2 layer were twisted together and coated with more mesoporous TiO2 to create a 3 dimensional photo electrode to overcome electron diffusion length issues. Archimedian yarns of MWNTs coated with a thin layer of platinum worked as a counter electrode to complete the architecture used in this DSSC.

  15. Design of hybrid nanoheterostructure systems for enhanced quantum and solar conversion efficiencies in dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Kılıç, Bayram; Telli, Hakan; Tüzemen, Sebahattin; Başaran, Ali; Pirge, Gursev

    2015-04-01

    Dye sensitized solar cells (DSSCs) with an innovative design involving controlled-morphology vertically aligned (VA) ZnO nanowires within mesoporous TiO2 structures with ultrahigh surface area for implementation as photoanodes are herein reported. Although TiO2 nanostructures exhibit excellent power conversion efficiency, the electron transport rate is low owing to low electron mobility. To overcome this, ZnO nanowires with high electron mobility have been investigated as potential candidates for photoanodes. However, the power conversion efficiency of ZnO nanowires is still lower than that of TiO2 owing to their low internal surface area. Consequently, in this work, vertical growth of ZnO nanowires within mesoporous TiO2 structures is carried out to increase their solar power conversion efficiency. The photovoltaic performance of solar cells using ZnO nanowires, mesoporous TiO2, and TiO2/ZnO hybrid structures are compared. The VA TiO2/ZnO hybrid structures are found to provide direct electron transfer compared with the tortuous pathway of zero-dimensional nanostructures, resulting in an increased conversion efficiency. It is demonstrated that the light scattering of the photoanode film is increased and electron recombination is decreased when an appropriate amount of mesoporous TiO2 is used as a substrate for ZnO nanowires. The DSSC fabricated with the TiO2/ZnO hybrid photoanode prepared with 15.8 wt. % TiO2 showed the highest conversion efficiency of 7.30%, approximately 5%, 18%, and 40% higher than that of DSSCs fabricated with 3.99 wt. % TiO2, pure TiO2, and pure ZnO photoanodes, respectively.

  16. Design of hybrid nanoheterostructure systems for enhanced quantum and solar conversion efficiencies in dye-sensitized solar cells

    SciTech Connect

    Kılıç, Bayram E-mail: kbayramkilic@gmail.com; Telli, Hakan; Başaran, Ali; Pirge, Gursev; Tüzemen, Sebahattin

    2015-04-07

    Dye sensitized solar cells (DSSCs) with an innovative design involving controlled-morphology vertically aligned (VA) ZnO nanowires within mesoporous TiO{sub 2} structures with ultrahigh surface area for implementation as photoanodes are herein reported. Although TiO{sub 2} nanostructures exhibit excellent power conversion efficiency, the electron transport rate is low owing to low electron mobility. To overcome this, ZnO nanowires with high electron mobility have been investigated as potential candidates for photoanodes. However, the power conversion efficiency of ZnO nanowires is still lower than that of TiO{sub 2} owing to their low internal surface area. Consequently, in this work, vertical growth of ZnO nanowires within mesoporous TiO{sub 2} structures is carried out to increase their solar power conversion efficiency. The photovoltaic performance of solar cells using ZnO nanowires, mesoporous TiO{sub 2}, and TiO{sub 2}/ZnO hybrid structures are compared. The VA TiO{sub 2}/ZnO hybrid structures are found to provide direct electron transfer compared with the tortuous pathway of zero-dimensional nanostructures, resulting in an increased conversion efficiency. It is demonstrated that the light scattering of the photoanode film is increased and electron recombination is decreased when an appropriate amount of mesoporous TiO{sub 2} is used as a substrate for ZnO nanowires. The DSSC fabricated with the TiO{sub 2}/ZnO hybrid photoanode prepared with 15.8 wt. % TiO{sub 2} showed the highest conversion efficiency of 7.30%, approximately 5%, 18%, and 40% higher than that of DSSCs fabricated with 3.99 wt. % TiO{sub 2}, pure TiO{sub 2}, and pure ZnO photoanodes, respectively.

  17. Enhanced Electron Lifetimes in Dye-Sensitized Solar Cells Using a Dichromophoric Porphyrin: The Utility of Intermolecular Forces.

    PubMed

    Zhao, Long; Wagner, Pawel; van der Salm, Holly; Gordon, Keith C; Mori, Shogo; Mozer, Attila J

    2015-10-01

    Electron lifetimes in dye-sensitized solar cells employing a porphyrin dye, an organic dye, a 1:1 mixture of the two dyes, and a dichromophoric dye design consisting of the two dyes using a nonconjugated linker were measured, suggesting that the dispersion force of the organic dyes has a significant detrimental effect on the electron lifetime and that the dichromophoric design can be utilized to control the effect of the dispersion force. PMID:26375165

  18. Preparation of anatase TiO2 nanorods with high aspect ratio for high-performance dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Tang, Ying; Wang, Chen; Hu, Yajing; Huang, Lu; Fu, Jianxun; Yang, Weiguang

    2016-01-01

    Due to offering a direct conduction pathway and fast electron transport, 1D nanostructures play an important role in improving charge collection efficiency in dye-sensitized solar cells (DSSCs). The anatase TiO2 nanorods with different aspect ratios between 3.2 and 6.3 were obtained by controlling reaction time for DSSCs. As their aspect ratios increased, more dye was adsorbed on the anatase TiO2 nanorods film. A promising power conversion efficiency of 7.51% was obtained for the anatase TiO2 nanorods with the biggest aspect ratio of 6.3.

  19. One-step femtosecond laser patterning of light-trapping structure on dye-sensitized solar cell photoelectrodes†

    PubMed Central

    Zhang, Xi; Liu, Hewei; Huang, Xuezhen; Jiang, Hongrui

    2015-01-01

    Light-trapping patterns were constructed in TiO2 photoelectrodes for dye-sensitized solar cells (DSSCs) by a one-step femtosecond laser structuring method that utilized ablation to create patterns at the surface of nanostructured TiO2 films. As a result, much more light was trapped in the photoelectrodes. Grating and orthogonal-grid patterns were studied, and the light trapping performance was optimized through the adjustment of pattern spacing, which was easily realized in the laser ablation process. With a 5-μm-spacing orthogonal-grid pattern, DSSCs showed a highest photon-to-electron conversion efficiency of 9.32% under AM 1.5G, a 13.5% improvement compared to the same cell without laser ablation. This simple and universal laser ablation method could be used to process many kinds of nanomaterials, and could be applied for various devices with nanostructures. PMID:26113977

  20. Realizing omnidirectional light harvesting by employing hierarchical architecture for dye sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Hsieh, Ming-Yang; Lai, Fang-I.; Chen, Wei-Chun; Hsieh, Min-Chi; Hu, Hsiang-Yi; Yu, Peichen; Kuo, Hao-Chung; Kuo, Shou-Yi

    2016-03-01

    To improve the omnidirectional light-harvesting in dye-sensitized solar cells (DSSCs), here we present a dandelion-like structure composed of ZnO hemispherical shells and nanorods. Uniformly distributed hemispherical shells effectively suppress the reflection over the broadband region at incident angles up to 60°, greatly improving the optical absorption of the DSSCs. In addition, modulating the length of the ZnO nanorods controls the omnidirectional characteristics of DSSCs. This phenomenon is attributed to the degree of periodicity of the ZnO dandelion-like structures. Cells with shorter rods exhibit a high degree of periodicity, thus the conversion efficiencies of the cells show specific angle-independent features. On the other hand, the cells with longer lengths reveal angle-dependent photovoltaic performance. Along with the simulation, the cells with dandelion-like ZnO structures can couple incident photons efficiently to achieve excellent broadband and omnidirectional light-harvesting performances experimentally, and the DSSCs enhanced the conversion efficiency by 48% at large incident angles. All these findings not only provide further insight into the light-trapping mechanism in these complex three-dimensional nanostructures but also offer efficient omnidirectional and broadband nanostructured photovoltaics for advanced applications.

  1. Realizing omnidirectional light harvesting by employing hierarchical architecture for dye sensitized solar cells.

    PubMed

    Hsieh, Ming-Yang; Lai, Fang-I; Chen, Wei-Chun; Hsieh, Min-Chi; Hu, Hsiang-Yi; Yu, Peichen; Kuo, Hao-Chung; Kuo, Shou-Yi

    2016-03-14

    To improve the omnidirectional light-harvesting in dye-sensitized solar cells (DSSCs), here we present a dandelion-like structure composed of ZnO hemispherical shells and nanorods. Uniformly distributed hemispherical shells effectively suppress the reflection over the broadband region at incident angles up to 60°, greatly improving the optical absorption of the DSSCs. In addition, modulating the length of the ZnO nanorods controls the omnidirectional characteristics of DSSCs. This phenomenon is attributed to the degree of periodicity of the ZnO dandelion-like structures. Cells with shorter rods exhibit a high degree of periodicity, thus the conversion efficiencies of the cells show specific angle-independent features. On the other hand, the cells with longer lengths reveal angle-dependent photovoltaic performance. Along with the simulation, the cells with dandelion-like ZnO structures can couple incident photons efficiently to achieve excellent broadband and omnidirectional light-harvesting performances experimentally, and the DSSCs enhanced the conversion efficiency by 48% at large incident angles. All these findings not only provide further insight into the light-trapping mechanism in these complex three-dimensional nanostructures but also offer efficient omnidirectional and broadband nanostructured photovoltaics for advanced applications. PMID:26899775

  2. Nanocomposite semi-solid redox ionic liquid electrolytes with enhanced charge-transport capabilities for dye-sensitized solar cells.

    PubMed

    Rutkowska, Iwona A; Marszalek, Magdalena; Orlowska, Justyna; Ozimek, Weronika; Zakeeruddin, Shaik M; Kulesza, Pawel J; Grätzel, Michael

    2015-08-10

    The ability of Pt nanostructures to induce the splitting of the II bond in iodine (triiodide) molecules is explored here to enhance electron transfer in the iodine/iodide redox couple. Following the dispersal of Pt nanoparticles at 2 % (weight) level, charge transport was accelerated in triiodide/iodide-containing 1,3-dialkylimidazolium room-temperature ionic liquid. If both Pt nanoparticles and multi-walled carbon nanotubes were introduced into the ionic-liquid-based system, a solid-type (nonfluid) electrolyte was obtained. By using solid-state voltammetric (both sandwich-type and microelectrode-based) methodology, the apparent diffusion coefficients for charge transport increased to approximately 1×10(-6)  cm(2)  s(-1) upon the incorporation of the carbon-nanotube-supported iodine-modified Pt nanostructures. A dye-sensitized solar cell comprising TiO2 covered with a heteroleptic Ru(II) -type sensitizer (dye) and the semisolid triiodide/iodide ionic liquid electrolyte admixed with carbon-nanotube-supported Pt nanostructures yielded somewhat higher power conversion efficiencies (up to 7.9 % under standard reporting conditions) than those of the analogous Pt-free system. PMID:26119519

  3. Review on Metallic and Plastic Flexible Dye Sensitized Solar Cell

    NASA Astrophysics Data System (ADS)

    Yugis, A. R.; Mansa, R. F.; Sipaut, C. S.

    2015-04-01

    Dye sensitized solar cells (DSSCs) are a promising alternative for the development of a new generation of photovoltaic devices. DSSCs have promoted intense research due to their low cost and eco-friendly advantage over conventional silicon-based crystalline solar cells. In recent years, lightweight flexible types of DSSCs have attracted much intention because of drastic reduction in production cost and more extensive application. The substrate that used as electrode of the DSSCs has a dominant impact on the methods and materials that can be applied to the cell and consequently on the resulting performance of DSSCs. Furthermore, the substrates influence significantly the stability of the device. Although the power conversion efficiency still low compared to traditional glass based DSSCs, flexible DSSCs still have potential to be the most efficient and easily implemented technology.

  4. Solar energy conversion by dye-sensitized photovoltaic cells.

    PubMed

    Grätzel, Michael

    2005-10-01

    The quality of human life depends to a large degree on the availability of energy. This is threatened unless renewable energy resources can be developed in the near future. Chemistry is expected to make important contributions to identify environmentally friendly solutions of the energy problem. One attractive strategy discussed in this Forum Article is the development of solar cells that are based on the sensitization of mesoscopic oxide films by dyes or quantum dots. These systems have already reached conversion efficiencies exceeding 11%. The underlying fundamental processes of light harvesting by the sensitizer, heterogeneous electron transfer from the electronically excited chromophore into the conduction band of the semiconductor oxide, and percolative migration of the injected electrons through the mesoporous film to the collector electrode will be described below in detail. A number of research topics will also be discussed, and the examples for the first outdoor application of such solar cells will be provided. PMID:16180840

  5. Device modeling of dye-sensitized solar cells.

    PubMed

    Bisquert, Juan; Marcus, Rudolph A

    2014-01-01

    We review the concepts and methods of modeling of the dye-sensitized solar cell, starting from fundamental electron transfer theory, and using phenomenological transport-conservation equations. The models revised here are aimed at describing the components of the current-voltage curve of the solar cell, based on small perturbation experimental methods, and to such an end, a range of phenomena occurring in the nanoparticulate electron transport materials, and at interfaces, are covered. Disorder plays a major role in the definition of kinetic parameters, and we introduce single particle as well as collective function definitions of diffusion coefficient and electron lifetime. Based on these fundamental considerations, applied tools of analysis of impedance spectroscopy are described, and we outline in detail the theory of recombination via surface states that is successful to describe the measured recombination resistance and lifetime. PMID:24085559

  6. Dye sensitized solar cells with carbon black as counter electrodes

    NASA Astrophysics Data System (ADS)

    Lin, Chi-Feng; Chou, Yu-Chen; Haung, Jhang-Fu; Chen, Pin-Hung; Han, Hsieh-Cheng; Chiu, Kuo-Yuan; Su, Yuhlong Oliver

    2016-03-01

    In this experiment, we use carbon black as counter electrodes to replace the conventional platinum electrodes in dye sensitized solar cell (DSSC). The electrical properties and device efficiency with carbon black counter electrodes with various concentrations, and under the annealing temperature from 100 to 500 °C are discussed. After the proper annealing process, the conductivity and redoxing ability of the carbon black is improved, resulted in the enhancement of the electrical characteristics, especially fill factor, of the device. The highest device efficiency was 7.28% with the JSC of 14.70 mA/cm2, VOC of 0.75 V, and fill factor of 0.67 under 1-sun AM 1.5G solar illumination.

  7. Nanostructured Materials Developed for Solar Cells

    NASA Technical Reports Server (NTRS)

    Bailey, Sheila G.; Castro, Stephanie L.; Raffaelle, Ryne P.; Fahey, Stephen D.; Gennett, Thomas; Tin, Padetha

    2004-01-01

    There has been considerable investigation recently regarding the potential for the use of nanomaterials and nanostructures to increase the efficiency of photovoltaic devices. Efforts at the NASA Glenn Research Center have involved the development and use of quantum dots and carbon nanotubes to enhance inorganic and organic cell efficiencies. Theoretical results have shown that a photovoltaic device with a single intermediate band of states resulting from the introduction of quantum dots offers a potential efficiency of 63.2 percent. A recent publication extended the intermediate band theory to two intermediate bands and calculated a limiting efficiency of 71.7 percent. The enhanced efficiency results from converting photons of energy less than the band gap of the cell by an intermediate band. The intermediate band provides a mechanism for low-energy photons to excite carriers across the energy gap by a two-step process.

  8. High Efficiency InP Solar Cells Through Nanostructuring

    NASA Astrophysics Data System (ADS)

    Goldman, Daniel; Murray, Joseph; Munday, Jeremy

    We describe high efficiency InP solar cells which utilize a periodic array of optically designed TiO2 nanocylinders. Optical and electronic simulations were performed to determine the spectrally resolved reflectivity and I-V characteristics of potential devices under AM1.5G illumination. The reflectivity of InP solar cells with these nanocylinders is found to have an average value of 2% over the visible and near-IR spectral range, which outperforms traditional antireflection coatings. Coupling between Mie scattering resonances and thin film interference effects is found to accurately describe the optical enhancement provided by the nanocylinders. These nanostructured solar cells have power conversion efficiencies greater than 23%, which is comparable to the highest quoted efficiencies for InP solar cells.

  9. Nanoscience and Nanostructures for Photovoltaics and Solar Fuels

    SciTech Connect

    Nozik, Arthur J.

    2010-07-02

    Quantum confinement of electronic particles (negative electrons and positive holes) in nanocrystals produces unique optical and electronic properties that have the potential to enhance the power conversion efficiency of solar cells for photovoltaic and solar fuels production at lower cost. These approaches and applications are labeled third generation solar photon conversion. Prominent among these unique properties is the efficient formation of more than one electron-hole pair (called excitons in nanocrystals) from a single absorbed photon. In isolated nanocrystals that have three-dimensional confinement of charge carriers (quantum dots) or two-dimensional confinement (quantum wires and rods) this process is termed multiple exciton generation. This Perspective presents a summary of our present understanding of the science of optoelectronic properties of nanocrystals and a prognosis for and review of the technological status of nanocrystals and nanostructures for third generation photovoltaic cells and solar fuels production.

  10. A dye sensitized solar cell using natural counter electrode and natural dye derived from mangosteen peel waste.

    PubMed

    Maiaugree, Wasan; Lowpa, Seksan; Towannang, Madsakorn; Rutphonsan, Phikun; Tangtrakarn, Apishok; Pimanpang, Samuk; Maiaugree, Prapen; Ratchapolthavisin, Nattawat; Sang-Aroon, Wichien; Jarernboon, Wirat; Amornkitbamrung, Vittaya

    2015-01-01

    Mangosteen peel is an inedible portion of a fruit. We are interested in using these residues as components of a dye sensitized solar cell (DSSC). Carbonized mangosteen peel was used with mangosteen peel dye as a natural counter electrode and a natural photosensitizer, respectively. A distinctive mesoporous honeycomb-like carbon structure with a rough nanoscale surface was found in carbonized mangosteen peels. The efficiency of a dye sensitized solar cell using carbonized mangosteen peel was compared to that of DSSCs with Pt and PEDOT-PSS counter electrodes. The highest solar conversion efficiency (2.63%) was obtained when using carbonized mangosteen peel and an organic disulfide/thiolate (T2/T(-)) electrolyte. PMID:26458745

  11. A dye sensitized solar cell using natural counter electrode and natural dye derived from mangosteen peel waste

    PubMed Central

    Maiaugree, Wasan; Lowpa, Seksan; Towannang, Madsakorn; Rutphonsan, Phikun; Tangtrakarn, Apishok; Pimanpang, Samuk; Maiaugree, Prapen; Ratchapolthavisin, Nattawat; Sang-aroon, Wichien; Jarernboon, Wirat; Amornkitbamrung, Vittaya

    2015-01-01

    Mangosteen peel is an inedible portion of a fruit. We are interested in using these residues as components of a dye sensitized solar cell (DSSC). Carbonized mangosteen peel was used with mangosteen peel dye as a natural counter electrode and a natural photosensitizer, respectively. A distinctive mesoporous honeycomb-like carbon structure with a rough nanoscale surface was found in carbonized mangosteen peels. The efficiency of a dye sensitized solar cell using carbonized mangosteen peel was compared to that of DSSCs with Pt and PEDOT-PSS counter electrodes. The highest solar conversion efficiency (2.63%) was obtained when using carbonized mangosteen peel and an organic disulfide/thiolate (T2/T−) electrolyte. PMID:26458745

  12. A dye sensitized solar cell using natural counter electrode and natural dye derived from mangosteen peel waste

    NASA Astrophysics Data System (ADS)

    Maiaugree, Wasan; Lowpa, Seksan; Towannang, Madsakorn; Rutphonsan, Phikun; Tangtrakarn, Apishok; Pimanpang, Samuk; Maiaugree, Prapen; Ratchapolthavisin, Nattawat; Sang-Aroon, Wichien; Jarernboon, Wirat; Amornkitbamrung, Vittaya

    2015-10-01

    Mangosteen peel is an inedible portion of a fruit. We are interested in using these residues as components of a dye sensitized solar cell (DSSC). Carbonized mangosteen peel was used with mangosteen peel dye as a natural counter electrode and a natural photosensitizer, respectively. A distinctive mesoporous honeycomb-like carbon structure with a rough nanoscale surface was found in carbonized mangosteen peels. The efficiency of a dye sensitized solar cell using carbonized mangosteen peel was compared to that of DSSCs with Pt and PEDOT-PSS counter electrodes. The highest solar conversion efficiency (2.63%) was obtained when using carbonized mangosteen peel and an organic disulfide/thiolate (T2/T-) electrolyte.

  13. Molecular design rule of phthalocyanine dyes for highly efficient near-IR performance in dye-sensitized solar cells.

    PubMed

    Kimura, Mutsumi; Nomoto, Hirotaka; Suzuki, Hiroyuki; Ikeuchi, Takuro; Matsuzaki, Hiroyuki; Murakami, Takuro N; Furube, Akihiko; Masaki, Naruhiko; Griffith, Matthew J; Mori, Shogo

    2013-06-01

    A series of zinc-phthalocyanine sensitizers (PcS16-18) with different adsorption sites have been designed and synthesized in order to investigate the dependence of adsorption-site structures on the solar-cell performances in zinc-phthalocyanine based dye-sensitized solar cells. The change of adsorption site affected the electron injection efficiency from the photoexcited dye into the nanocrystalline TiO2 semiconductor, as monitored by picosecond time-resolved fluorescence spectroscopy. The zinc-phthalocyanine sensitizer PcS18, possessing one carboxylic acid directly attached to the ZnPc ring and six 2,6-diisopropylphenoxy units, showed a record power conversion efficiency value of 5.9 % when used as a light-harvesting dye on a TiO2 electrode under one simulated solar condition. PMID:23576330

  14. Ultrasound stimulated nucleation and growth of a dye assembly into extended gel nanostructures.

    PubMed

    Malicka, Joanna M; Sandeep, Anjamkudy; Monti, Filippo; Bandini, Elisa; Gazzano, Massimo; Ranjith, Choorikkat; Praveen, Vakayil K; Ajayaghosh, Ayyappanpillai; Armaroli, Nicola

    2013-09-23

    A squaraine dye functionalized with a bulky trialkoxy phenyl moiety through a flexible diamide linkage (GA-SQ) capable of undergoing self-assembly has been synthesized and fully characterized. Rapid cooling of a hot solution of GA-SQ to 0 °C results in self-assembled precipitates consisting of two types of nanostructures, rings and ill-defined short fibers. The application of ultrasound modifies the conditions for the supersaturation-mediated nucleation, generating only one kind of nuclei and prompting the formation of crystalline fibrous structures, inducing gelation of solvent molecules. The unique self-assembling behavior of GA-SQ under ultrasound stimulus has been investigated in detail by using absorption, emission, FT-IR, XRD, SEM, AFM and TEM techniques. These studies reveal a nucleation growth mechanism of the self-assembled material, an aspect rarely scrutinized in the area of sonication-induced gelation. Furthermore, in order to probe the effects of nanoscale substrates on the sonication-induced self-assembly, a minuscule amount of single-walled carbon nanotubes was added, which leads to acceleration of the self-assembly through a heterogeneous nucleation process that ultimately affords a supramolecular gel with nanotape-like morphology. This study demonstrates that self-assembly of functional dyes can be judiciously manipulated by an external stimulus and can be further controlled by the addition of carbon nanotubes. PMID:23913577

  15. Efficient dye regeneration at low driving force achieved in triphenylamine dye LEG4 and TEMPO redox mediator based dye-sensitized solar cells.

    PubMed

    Yang, Wenxing; Vlachopoulos, Nick; Hao, Yan; Hagfeldt, Anders; Boschloo, Gerrit

    2015-06-28

    Minimizing the driving force required for the regeneration of oxidized dyes using redox mediators in an electrolyte is essential to further improve the open-circuit voltage and efficiency of dye-sensitized solar cells (DSSCs). Appropriate combinations of redox mediators and dye molecules should be explored to achieve this goal. Herein, we present a triphenylamine dye, LEG4, in combination with a TEMPO-based electrolyte in acetonitrile (E(0) = 0.89 V vs. NHE), reaching an efficiency of up to 5.4% under one sun illumination and 40% performance improvement compared to the previously and widely used indoline dye D149. The origin of this improvement was found to be the increased dye regeneration efficiency of LEG4 using the TEMPO redox mediator, which regenerated more than 80% of the oxidized dye with a driving force of only ∼0.2 eV. Detailed mechanistic studies further revealed that in addition to electron recombination to oxidized dyes, recombination of electrons from the conducting substrate and the mesoporous TiO2 film to the TEMPO(+) redox species in the electrolyte accounts for the reduced short circuit current, compared to the state-of-the-art cobalt tris(bipyridine) electrolyte system. The diffusion length of the TEMPO-electrolyte based DSSCs was determined to be ∼0.5 μm, which is smaller than the ∼2.8 μm found for cobalt-electrolyte based DSSCs. These results show the advantages of using LEG4 as a sensitizer, compared to previously record indoline dyes, in combination with a TEMPO-based electrolyte. The low driving force for efficient dye regeneration presented by these results shows the potential to further improve the power conversion efficiency (PCE) of DSSCs by utilizing redox couples and dyes with a minimal need of driving force for high regeneration yields. PMID:26016854

  16. Dyes and Redox Couples with Matched Energy Levels: Elimination of the Dye-Regeneration Energy Loss in Dye-Sensitized Solar Cells.

    PubMed

    Jiang, Dianlu; Darabedian, Narek; Ghazarian, Sevak; Hao, Yuanqiang; Zhgamadze, Maxim; Majaryan, Natalie; Shen, Rujuan; Zhou, Feimeng

    2015-11-16

    In dye-sensitized solar cells (DSSCs), a significant dye-regeneration force (ΔG(reg)(0)≥0.5 eV) is usually required for effective dye regeneration, which results in a major energy loss and limits the energy-conversion efficiency of state-of-art DSSCs. We demonstrate that when dye molecules and redox couples that possess similar conjugated ligands are used, efficient dye regeneration occurs with zero or close-to-zero driving force. By using Ru(dcbpy)(bpy)2(2+) as the dye and Ru(bpy)2(MeIm)2(3+//2+) as the redox couple, a short-circuit current (J(sc)) of 4 mA cm(-2) and an open-circuit voltage (V(oc)) of 0.9 V were obtained with a ΔG(reg)(0) of 0.07 eV. The same was observed for the N3 dye and Ru(bpy)2(SCN)2(1+/0) (ΔG(reg)(0)=0.0 eV), which produced an J(sc) of 2.5 mA cm(-2) and V(oc) of 0.6 V. Charge recombination occurs at pinholes, limiting the performance of the cells. This proof-of-concept study demonstrates that high V(oc) values can be attained by significantly curtailing the dye-regeneration force. PMID:26314383

  17. Conditions for diffusion-limited and reaction-limited recombination in nanostructured solar cells

    SciTech Connect

    Ansari-Rad, Mehdi; Anta, Juan A.; Arzi, Ezatollah

    2014-04-07

    The performance of Dye-sensitized solar cells (DSC) and related devices made of nanostructured semiconductors relies on a good charge separation, which in turn is achieved by favoring charge transport against recombination. Although both processes occur at very different time scales, hence ensuring good charge separation, in certain cases the kinetics of transport and recombination can be connected, either in a direct or an indirect way. In this work, the connection between electron transport and recombination in nanostructured solar cells is studied both theoretically and by Monte Carlo simulation. Calculations using the Multiple-Trapping model and a realistic trap distribution for nanostructured TiO{sub 2} show that for attempt-to-jump frequencies higher than 10{sup 11}–10{sup 13} Hz, the system adopts a reaction limited (RL) regime, with a lifetime which is effectively independent from the speed of the electrons in the transport level. For frequencies lower than those, and depending on the concentration of recombination centers in the material, the system enters a diffusion-limited regime (DL), where the lifetime increases if the speed of free electrons decreases. In general, the conditions for RL or DL recombination depend critically on the time scale difference between recombination kinetics and free-electron transport. Hence, if the former is too rapid with respect to the latter, the system is in the DL regime and total thermalization of carriers is not possible. In the opposite situation, a RL regime arises. Numerical data available in the literature, and the behavior of the lifetime with respect to (1) density of recombination centers and (2) probability of recombination at a given center, suggest that a typical DSC in operation stays in the RL regime with complete thermalization, although a transition to the DL regime may occur for electrolytes or hole conductors where recombination is especially rapid or where there is a larger dispersion of energies of

  18. Natural dyes as sensitizers to increase the efficiency in sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Cerda, Bayron; Sivakumar, R.; Paulraj, M.

    2016-05-01

    A dye-sensitized solar cell (DSSC) is a sandwich type solar cell consisting of a photoelectrode, a counter electrode and a liquid electrolyte. The photo electrode comprises of a titanium dioxide semiconducting thin film grown over a glass substrate which in-turn has a transparent thin conducting layer of tin oxide film doped with fluorine (FTO) coated over it. The aim of this work is to develop photoelectrodes with different dyes to increase the efficiency of this type of solar cells. Dyes obtained from fresh sources of maqui, black myrtle, spinach and a dye mixture of spinach and spinach-maqui-myrtle were used. The technique used for the extraction of the dyes was maceration for one day, in methanol. Colourants and photoelectrodes were studied using, UV-vis spectrophotometer for their spectral properties. Their photovoltaic properties such as efficiency, fill factor, open circuit voltage and short circuit current were studied using a solar simulator and source meter unit.

  19. Nanostructured Solar Irradiation Control Materials for Solar Energy Conversion

    NASA Technical Reports Server (NTRS)

    Kang, Jinho; Marshall, I. A.; Torrico, M. N.; Taylor, C. R.; Ely, Jeffry; Henderson, Angel Z.; Kim, J.-W.; Sauti, G.; Gibbons, L. J.; Park, C.; Lowther, S. E.; Lillehei, P. T.; Bryant, R. G.

    2012-01-01

    Tailoring the solar absorptivity (alpha(sub s)) and thermal emissivity (epsilon(sub T)) of materials constitutes an innovative approach to solar energy control and energy conversion. Numerous ceramic and metallic materials are currently available for solar absorbance/thermal emittance control. However, conventional metal oxides and dielectric/metal/dielectric multi-coatings have limited utility due to residual shear stresses resulting from the different coefficient of thermal expansion of the layered materials. This research presents an alternate approach based on nanoparticle-filled polymers to afford mechanically durable solar-absorptive and thermally-emissive polymer nanocomposites. The alpha(sub s) and epsilon(sub T) were measured with various nano inclusions, such as carbon nanophase particles (CNPs), at different concentrations. Research has shown that adding only 5 wt% CNPs increased the alpha(sub s) and epsilon(sub T) by a factor of about 47 and 2, respectively, compared to the pristine polymer. The effect of solar irradiation control of the nanocomposite on solar energy conversion was studied. The solar irradiation control coatings increased the power generation of solar thermoelectric cells by more than 380% compared to that of a control power cell without solar irradiation control coatings.

  20. The impact of active layer nanomorphology on the efficiency of organic solar cells based on a squaraine dye electron donor

    NASA Astrophysics Data System (ADS)

    Stoyanova, D.; Kitova, S.; Dikova, J.; Kandinska, M.; Vasilev, A.; Zhivkov, I.; Kovalenko, A.

    2016-03-01

    The possibilities were studied of improving the photovoltaic performance of solution processed BHJ solar cells by solvent vapor annealing (SVA) of the active layers, based on a squaraine dye Sq1 as a donor and the fullerene derivative PCBM as an acceptor. For this purpose, the optical properties were determined of as-deposited and of annealed with tetrahydrofuran (THF) vapors for different duration Sq1/PCMB layers, as well as the efficiency of cells built on their basis. A considerable change was established in the absorption spectra of treated for only a few seconds films and a twofold increase of the power conversion efficiency after 6 sec SVA. The results obtained are explained in terms of solvent vapor induced phase separation and formation of squaraine dye small aggregates in the blend nanostructure. The assumption made was confirmed by morphological investigation of as-deposited and of annealed Sq1/PCBM blended layers. On this basis, the impact of the active layer nanomorphology on the efficiency of solar cells based on squariane dye as electron donor is discussed.

  1. Highly stable tandem solar cell monolithically integrating dye-sensitized and CIGS solar cells

    PubMed Central

    Chae, Sang Youn; Park, Se Jin; Joo, Oh-Shim; Jun, Yongseok; Min, Byoung Koun; Hwang, Yun Jeong

    2016-01-01

    A highly stable monolithic tandem solar cell was developed by combining the heterogeneous photovoltaic technologies of dye-sensitized solar cell (DSSC) and solution-processed CuInxGa1-xSeyS1-y (CIGS) thin film solar cells. The durability of the tandem cell was dramatically enhanced by replacing the redox couple from to [Co(bpy)3]2+ /[Co(bpy)3]3+), accompanied by a well-matched counter electrode (PEDOT:PSS) and sensitizer (Y123). A 1000 h durability test of the DSSC/CIGS tandem solar cell in ambient conditions resulted in only a 5% decrease in solar cell efficiency. Based on electrochemical impedance spectroscopy and photoelectrochemical cell measurement, the enhanced stability of the tandem cell is attributed to minimal corrosion by the cobalt-based polypyridine complex redox couple. PMID:27489138

  2. Highly stable tandem solar cell monolithically integrating dye-sensitized and CIGS solar cells

    NASA Astrophysics Data System (ADS)

    Chae, Sang Youn; Park, Se Jin; Joo, Oh-Shim; Jun, Yongseok; Min, Byoung Koun; Hwang, Yun Jeong

    2016-08-01

    A highly stable monolithic tandem solar cell was developed by combining the heterogeneous photovoltaic technologies of dye-sensitized solar cell (DSSC) and solution-processed CuInxGa1-xSeyS1-y (CIGS) thin film solar cells. The durability of the tandem cell was dramatically enhanced by replacing the redox couple from to [Co(bpy)3]2+ /[Co(bpy)3]3+), accompanied by a well-matched counter electrode (PEDOT:PSS) and sensitizer (Y123). A 1000 h durability test of the DSSC/CIGS tandem solar cell in ambient conditions resulted in only a 5% decrease in solar cell efficiency. Based on electrochemical impedance spectroscopy and photoelectrochemical cell measurement, the enhanced stability of the tandem cell is attributed to minimal corrosion by the cobalt-based polypyridine complex redox couple.

  3. Metal-Free Sensitizers for Dye-Sensitized Solar Cells.

    PubMed

    Chaurasia, Sumit; Lin, Jiann T

    2016-06-01

    This review focuses on our work on metal-free sensitizers for dye-sensitized solar cells (DSSCs). Sensitizers based on D-A'-π-A architecture (D is a donor, A is an acceptor, A' is an electron-deficient entity) exhibit better light harvesting than D-π-A-type sensitizers. However, appropriate molecular design is needed to avoid excessive aggregation of negative charge at the electron-deficient entity upon photoexcitation. Rigidified aromatics, including aromatic segments comprising fused electron-excessive and -deficient units in the spacer, allow effective electronic communication, and good photoinduced charge transfer leads to excellent cell performance. Sensitizers with two anchors/acceptors, D(-π-A)2 , can more efficiently harvest light, inject electrons, and suppress dark current compared with congeners with a single anchor. Appropriate incorporation of heteroaromatic units in the spacer is beneficial to DSSC performance. High-performance, aqueous-based DSSCs can be achieved with a dual redox couple comprising imidazolium iodide and 2,2,6,6-tetramethylpiperidin-N-oxyl, and/or using dyes of improved wettability through the incorporation of a triethylene oxide methyl ether chain. PMID:27114164

  4. Characteristics of SnO2 nanofiber/TiO2 nanoparticle composite for dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Gong, Jiawei; Qiao, Hui; Sigdel, Sudhan; Elbohy, Hytham; Adhikari, Nirmal; Zhou, Zhengping; Sumathy, K.; Wei, Qufu; Qiao, Qiquan

    2015-06-01

    SnO2 nanofibers and their composites based photoanodes were fabricated and investigated in the application of dye-sensitized solar cells. The photoanode made of SnO2/TiO2 composites yielded an over 2-fold improvement in overall conversion efficiency. The microstructure of SnO2 nanofibers was characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). A compact morphology of composites was observed using scanning electron microscopy (SEM). A long charge diffusion length (62.42 μm) in the composites was derived from time constant in transient photovoltage and photocurrent analysis. These experimental results demonstrate that one-dimensional nanostructured SnO2/TiO2 composites have a great potential for application in solar cells.

  5. Nano-structured electron transporting materials for perovskite solar cells.

    PubMed

    Liu, Hefei; Huang, Ziru; Wei, Shiyuan; Zheng, Lingling; Xiao, Lixin; Gong, Qihuang

    2016-03-17

    Organic-inorganic hybrid perovskite solar cells have been developing rapidly in the past several years, and their power conversion efficiency has reached over 20%, nearing that of polycrystalline silicon solar cells. Because the diffusion length of the hole in perovskites is longer than that of the electron, the performance of the device can be improved by using an electron transporting layer, e.g., TiO2, ZnO and TiO2/Al2O3. Nano-structured electron transporting materials facilitate not only electron collection but also morphology control of the perovskites. The properties, morphology and preparation methods of perovskites are reviewed in the present article. A comprehensive understanding of the relationship between the structure and property will benefit the precise control of the electron transporting process and thus further improve the performance of perovskite solar cells. PMID:26457406

  6. Nano-structured electron transporting materials for perovskite solar cells

    NASA Astrophysics Data System (ADS)

    Liu, Hefei; Huang, Ziru; Wei, Shiyuan; Zheng, Lingling; Xiao, Lixin; Gong, Qihuang

    2016-03-01

    Organic-inorganic hybrid perovskite solar cells have been developing rapidly in the past several years, and their power conversion efficiency has reached over 20%, nearing that of polycrystalline silicon solar cells. Because the diffusion length of the hole in perovskites is longer than that of the electron, the performance of the device can be improved by using an electron transporting layer, e.g., TiO2, ZnO and TiO2/Al2O3. Nano-structured electron transporting materials facilitate not only electron collection but also morphology control of the perovskites. The properties, morphology and preparation methods of perovskites are reviewed in the present article. A comprehensive understanding of the relationship between the structure and property will benefit the precise control of the electron transporting process and thus further improve the performance of perovskite solar cells.

  7. Carbon Nanotubes for Dye-Sensitized Solar Cells.

    PubMed

    Batmunkh, Munkhbayar; Biggs, Mark J; Shapter, Joseph G

    2015-07-01

    As one type of emerging photovoltaic cell, dye-sensitized solar cells (DSSCs) are an attractive potential source of renewable energy due to their eco-friendliness, ease of fabrication, and cost effectiveness. However, in DSSCs, the rarity and high cost of some electrode materials (transparent conducting oxide and platinum) and the inefficient performance caused by slow electron transport, poor light-harvesting efficiency, and significant charge recombination are critical issues. Recent research has shown that carbon nanotubes (CNTs) are promising candidates to overcome these issues due to their unique electrical, optical, chemical, physical, as well as catalytic properties. This article provides a comprehensive review of the research that has focused on the application of CNTs and their hybrids in transparent conducting electrodes (TCEs), in semiconducting layers, and in counter electrodes of DSSCs. At the end of this review, some important research directions for the future use of CNTs in DSSCs are also provided. PMID:25864907

  8. Highly efficient monolithic dye-sensitized solar cells.

    PubMed

    Kwon, Jeong; Park, Nam-Gyu; Lee, Jun Young; Ko, Min Jae; Park, Jong Hyeok

    2013-03-01

    Monolithic dye-sensitized solar cells (M-DSSCs) provide an effective way to reduce the fabrication cost of general DSSCs since they do not require transparent conducting oxide substrates for the counter electrode. However, conventional monolithic devices have low efficiency because of the impediments resulting from counter electrode materials and spacer layers. Here, we demonstrate highly efficient M-DSSCs featuring a highly conductive polymer combined with macroporous polymer spacer layers. With M-DSSCs based on a PEDOT/polymer spacer layer, a power conversion efficiency of 7.73% was achieved, which is, to the best of our knowledge, the highest efficiency for M-DSSCs to date. Further, PEDOT/polymer spacer layers were applied to flexible DSSCs and their cell performance was investigated. PMID:23432389

  9. Dye Sensitized Solar Cells for Economically Viable Photovoltaic Systems.

    PubMed

    Jung, Hyun Suk; Lee, Jung-Kun

    2013-05-16

    TiO2 nanoparticle-based dye sensitized solar cells (DSSCs) have attracted a significant level of scientific and technological interest for their potential as economically viable photovoltaic devices. While DSSCs have multiple benefits such as material abundance, a short energy payback period, constant power output, and compatibility with flexible applications, there are still several challenges that hold back large scale commercialization. Critical factors determining the future of DSSCs involve energy conversion efficiency, long-term stability, and production cost. Continuous advancement of their long-term stability suggests that state-of-the-art DSSCs will operate for over 20 years without a significant decrease in performance. Nevertheless, key questions remain in regards to energy conversion efficiency improvements and material cost reduction. In this Perspective, the present state of the field and the ongoing efforts to address the requirements of DSSCs are summarized with views on the future of DSSCs. PMID:26282979

  10. Space Environmental Testing of Dye-Sensitized Solar Cells

    NASA Technical Reports Server (NTRS)

    Harris, Jerry D.; Anglin, Emily J.; Hepp, Aloysius F.; Bailey, Sheila G.; Scheiman, David A.; Castro, Stephenie L.; Lyons, Valerie (Technical Monitor)

    2002-01-01

    Recent advances in nanocrystalline dye-sensitized solar cells has lead NASA to investigate the potential of these devices for space power generation, Reported here is the first space environment characterization of these type of photovoltaic devices. Cells containing liquid electrolytes were exposed to simulated low-earth orbit conditions and their performance evaluated. All cells were characterized under simulated air mass zero (AMO) illumination. Complete cells were exposed to pressures less than 1 x 10(exp -7) torr for over a month, with no sign of sealant failure or electrolyte leakage. Cells from Solaronix SA were rapid thermal cycled under simulated low-earth orbit conditions. The cells were cycled 100 times from -80 C to 80 C, which is equivalent to 6 days in orbit. The best cell had a 4.6% loss in efficiency as a result of the thermal cycling,

  11. Optimizing the Performance of a Plastic Dye Sensitized Solar Cell

    SciTech Connect

    Lee, B.; Buchholz, D.; Guo, P.; Hwang, D.; Chang, R.P.H.

    2011-05-19

    This article describes that a fluorine plasma treatment can increase the nanopore filling of a plastic electrolyte in a dye-sensitized solar cell to improve its performance. The one-step fluorine treatment can be used in a controlled way to increase the size of nanopores and nanochannels in the TiO{sub 2} nanoparticle electrode and, at the same time, passivate the TiO{sub 2} nanoparticle surfaces. In combination with the fluorine treatment, a sequential electrolyte filling process has been developed that allows the overall cell conversion efficiency to be increased by as much as 25%. The plastic-based electrolyte cells are found to be much more stable compared with their counterpart, the liquid electrolyte cells. Using this new process, and in combination with a photon confinement scheme, the overall cell efficiency can reach to about 9% using a masked frame measurement technique.

  12. Mesoporous multi-shelled ZnO microspheres for the scattering layer of dye sensitized solar cell with a high efficiency

    NASA Astrophysics Data System (ADS)

    Xia, Weiwei; Mei, Chao; Zeng, Xianghua; Chang, Shuai; Wu, Guoqing; Shen, Xiaoshuang

    2016-03-01

    Both light scattering and dye adsorbing are important for the power conversion efficiency PCE performance of dye sensitized solar cell (DSSC). Nanostructured scattering layers with a large specific surface area are regarded as an efficient way to improve the PCE by increasing dye adsorbing, but excess adsorbed dye will hinder light scattering and light penetration. Thus, how to balance the dye adsorbing and light penetration is a key problem to improve the PCE performance. Here, multiple-shelled ZnO microspheres with a mesoporous surface are fabricated by a hydrothermal method and are used as scattering layers on the TiO2 photoanode of the DSSC in the presence of N719 dye and iodine-based electrolyte, and the results reveal that the DSSCs based on triple shelled ZnO microsphere with a mesoporous surface exhibit an enhanced PCE of 7.66%, which is 13.0% higher than those without the scattering layers (6.78%), indicating that multiple-shelled microspheres with a mesoporous surface can ensure enough light scattering between the shells, and a favorable concentration of the adsorbed dye can improve the light penetration. These results may provide a promising pathway to obtain the high efficient DSSCs.

  13. Improved solar efficiency by introducing graphene oxide in purple cabbage dye sensitized TiO2 based solar cell

    NASA Astrophysics Data System (ADS)

    Al-Ghamdi, Ahmed A.; Gupta, R. K.; Kahol, P. K.; Wageh, S.; Al-Turki, Y. A.; El Shirbeeny, W.; Yakuphanoglu, F.

    2014-04-01

    Natural dye extracted from purple cabbage was used for fabrication of TiO2 dye-sensitized solar cells (DSSCs). The effect of light intensity on the solar efficiency of the device was investigated. It was observed that the efficiency of the DSSC increases with increasing the light intensity e.g. the efficiency of the solar cell increases from 0.013±0.002% to 0.150±0.020% by increase in light intensity from 30 to 100 mW/cm2, respectively. The solar efficiency of the natural dye used in this research was compared with commercial dye (N 719) under similar experimental conditions and observed that the natural (purple cabbage) dye has higher efficiency (0.150±0.020%) than N 719 (0.078±0.002%). It was further evaluated that the efficiency of the fabricated solar cell could improve by incorporating graphene oxide. The efficiency of the TiO2 dye-sensitized solar cell was found to increase from 0.150±0.020% to 0.361±0.009% by incorporating graphene oxide into purple cabbage dye.

  14. On the performance of ruthenium dyes in dye sensitized solar cells: a free cluster approach based on theoretical indexes.

    PubMed

    Barrera, M; Crivelli, I; Loeb, B

    2016-05-01

    The performance of ruthenium dye sensitized solar cells (DSSC) with different types of ligand was studied by means of a theoretical model where the ruthenium complex is bound to two [Ti(OH)3](+) units, instead of the more usual cluster TiO2 model. Electron injection is proposed to proceed from a thermalized (3)MLCT state rather than from higher vibrational excited states. The efficiency of the dye linked to the two [Ti(OH)3](+) units was determined in terms of a global index (ξ), calculated as the product of three theoretical indexes (FI) built from the results of time-dependent density functional theory (TDDFT) calculations. The index considers the harvested and delivered energy (F1), the charge transferred to the semiconductor (F2), and dye regeneration (F3). The results show that this set of parameters is unique for each dye, and allows the comparative evaluation of the performance of a series of dyes, with a different ancillary ligand at each stage of the cell operation. The method provides insights that can help explain the improved performance of N3 and black dyes compared to other dyes. Graphical abstract Calculated global efficiency for complexes C1-C6. Inset General structure of the interacting model. PMID:27138946

  15. Performance of Kerria japonica and Rosa chinensis flower dyes as sensitizers for dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Hemalatha, K. V.; Karthick, S. N.; Justin Raj, C.; Hong, N.-Y.; Kim, S.-K.; Kim, H.-J.

    2012-10-01

    The natural dyes carotenoid and anthocyanin were extracted from Kerria japonica and Rosa chinensis, respectively, using a simple extraction technique without any further purification. They were then used as sensitizers in dye-sensitized solar cells (DSSCs), and their characteristics were studied. The ranges of short-circuit current (JSC) from 0.559 to 0.801 (mA/cm2), open-circuit voltage (VOC) from 0.537 to 0.584 V, and fill factor from 0.676 to 0.705 were obtained for the DSSCs made using the extracted dyes. Sugar molecules were added externally to the dye for stabilization and to increase the conversion efficiency. The efficiencies of the K. japonica and R. chinensis dyes were 0.22% and 0.29%, respectively; after the addition of sugar, the efficiency increased to 0.29% for K. japonica and decreased to 0.27% for R. chinensis. Thus, the addition of sugar molecules increased the conversion efficiency slightly with the carotenoid dye of K. japonica, while there was no considerable change with the anthocyanin of R. chinensis. This paper briefly discusses the simple extraction technique of these natural dyes and their performance in DSSCs.

  16. Performance of Kerria japonica and Rosa chinensis flower dyes as sensitizers for dye-sensitized solar cells.

    PubMed

    Hemalatha, K V; Karthick, S N; Justin Raj, C; Hong, N-Y; Kim, S-K; Kim, H-J

    2012-10-01

    The natural dyes carotenoid and anthocyanin were extracted from Kerria japonica and Rosa chinensis, respectively, using a simple extraction technique without any further purification. They were then used as sensitizers in dye-sensitized solar cells (DSSCs), and their characteristics were studied. The ranges of short-circuit current (J(SC)) from 0.559 to 0.801(mA/cm(2)), open-circuit voltage (V(OC)) from 0.537 to 0.584 V, and fill factor from 0.676 to 0.705 were obtained for the DSSCs made using the extracted dyes. Sugar molecules were added externally to the dye for stabilization and to increase the conversion efficiency. The efficiencies of the K. japonica and R. chinensis dyes were 0.22% and 0.29%, respectively; after the addition of sugar, the efficiency increased to 0.29% for K. japonica and decreased to 0.27% for R. chinensis. Thus, the addition of sugar molecules increased the conversion efficiency slightly with the carotenoid dye of K. japonica, while there was no considerable change with the anthocyanin of R. chinensis. This paper briefly discusses the simple extraction technique of these natural dyes and their performance in DSSCs. PMID:22698848

  17. Visible to near infra red absorption in natural dye (Mondo Grass Berry) for Dye Sensitized Solar Cell

    NASA Astrophysics Data System (ADS)

    Pitigala, Duleepa; Desilva, L. A. A.; Perera, A. G. U.

    2012-03-01

    The development of dye sensitized solar cells (DSSC) is an exciting field in the low cost renewable energy production. Two major draw backs in the DSSCs are the narrow spectral response and the short term stability. Research on development of artificial dyes for broadening the response is important in finding a solution. Work presented here shows a broad spectral response with a natural dye extracted from a Mondo Grass berry (Ophiopogonjaponicus).The dye is extracted by crushing the berries and filtering to remove the pulp. A DSSC sensitized with Mondo Grass dye, and with TiO2 film screen printed on a Florien doped Tin Oxide (FTO) glass and baked for 30 minutes at 450 C as the working electrode and Iodine/triiodide red-ox electrolyte as the hole collector was tested for its performance. An open circuit photovoltage of 495 mV and a short circuit photocurrent of 0.6 mA/cm2were observed under a simulated lamp equivalent to 1 sun illumination. The broad spectral response from 400 nm to 750 nm was also observed for the Mondo Grass dye compared to other natural dyes consists of anthocyanins or tannins.

  18. Chemisorption of a thiol-functionalized ruthenium dye on zinc oxide nanoparticles: Implications for dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Singh, Jagdeep; Im, Jisun; Whitten, James E.; Soares, Jason W.; Steeves, Diane M.

    2010-09-01

    ZnO is an alternative to TiO 2-based dye-sensitized solar cells (DSSCs). Adsorption of cis-ruthenium-bis[2,2'-bipyridine]-bis[4-thiopyridine] onto ZnO nanorods has been studied using X-ray and ultraviolet photoelectron spectroscopies (XPS and UPS). XPS indicates chemisorption with a surface density of ca. 1 × 10 15 molecules/cm 2, confirming the possibility of using thiol-terminated dyes for ZnO-based DSSC devices. The energy level diagram, based on UPS and absorbance spectroscopy, indicates that the LUMO of this dye is lower in energy than the ZnO conduction band edge, providing minimal enthalpic driving force for photovoltaic electron injection. However, optimization of thiol-functionalized Ru dyes could result in competitive ZnO-based DSSCs.

  19. Parametric Optimization of Experimental Conditions for Dye-Sensitized Solar Cells based on Far-red Sensitive Squaraine Dye

    NASA Astrophysics Data System (ADS)

    Morimoto, Takuya; Fujikawa, Naotaka; Ogomi, Yuhei; Pandey, Shyam S.; Hayase, Shuzi

    2016-04-01

    A far-red sensitive unsymmetrical squaraine dye SQ-41 has been synthesized and subjected to the fabrication of dye-sensitized solar cells by varying the various parameters in order attain optimum photoconversion efficiency (η). It has been demonstrated that an optimum ratio of dye to coadsorber, thickness of mesoporous TiO2 layer, redox electrolyte and surface treatment are necessary to enhance overall external η. In the case of surface treatment, it has been shown to exhibit pronounced device performance when both of the FTO as well mesoporous TiO2 surfaces were treated with aqueous TiCl4. In spite of very high molar extinction coefficient of dye SQ-41, 10-12 µm thickness of mesoporous TiO2 was found to be necessary to attain the maximum η.

  20. Computational design of small phenothiazine dyes for dye-sensitized solar cells by functionalizations affecting the thiophene unit.

    PubMed

    Tu, Wei Han; Tan, Yi Yin; Rege, Omkar; Manzhos, Sergei

    2015-04-01

    We present a computational density functional theory study of the potential to improve the solar absorbance of small organic dyes featuring a phenothiazine donor and an acceptor moiety that combines a thiophene unit and a cyanoacrylic group. We consider different conjugation orders and functional groups on and around the thiophene unit, including electron-donating and electron-withdrawing moieties (H, F, CH3, CF3, and CN). We predict that by combining change of conjugation order and functionalization with electron withdrawing CN groups, it must be possible to decrease the excitation energy by up to 60 % vs. the parent dye (which would correspond to a redshift of the absorption peak maximum from 450 nm to 726 nm), effectively enabling red light absorption with small dyes. The contraction of the band gap is mostly due to the stabilization of the LUMO (by up to 1.8 eV), so that-in spite of the kinetic redundancy of the parent dye with respect to the conduction-band minimum of TiO2-care must be taken to ensure efficient injection when using the dyes in dye-sensitized solar cells. By studying 50 dyes, of which 44 are new dyes that are studied for the first time in this work, we identify parameters (such as charges, dihedral angles between donor and acceptor groups, bond length alternation) which can serve as predictors of the band gap. We find that bond length alternation or dihedral angles are not good predictors, while the charge on the thiophene unit is. PMID:25750021

  1. To probe the equivalence and opulence of nanocrystal and nanotube based dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Jyoti, Divya; Mohan, Devendra

    2016-05-01

    Dye-Sensitized solar cells based on TiO2 nanocrystal and TiO2 nanotubes have been fabricated by a simple sol-gel hydrothermal process and their performances have been compared. Current density and voltage (JV) characteristics and incident photon to current conversion efficiency (IPCE) plots have been set as criterion to check which one is better as a photoanode candidate in dye-sensitized solar cell. It has been observed that although open circuit voltage values for both type of cells do not differ much still, nanotube based dye-sensitized solar cells are more successful having an efficiency value of 7.28%.

  2. EH AND S ANALYSIS OF DYE-SENSITIZED PHOTOVOLTAIC SOLAR CELL PRODUCTION.

    SciTech Connect

    BOWERMAN,B.; FTHENAKIS,V.

    2001-10-01

    Photovoltaic solar cells based on a dye-sensitized nanocrystalline titanium dioxide photoelectrode have been researched and reported since the early 1990's. Commercial production of dye-sensitized photovoltaic solar cells has recently been reported in Australia. In this report, current manufacturing methods are described, and estimates are made of annual chemical use and emissions during production. Environmental, health and safety considerations for handling these materials are discussed. This preliminary EH and S evaluation of dye-sensitized titanium dioxide solar cells indicates that some precautions will be necessary to mitigate hazards that could result in worker exposure. Additional information required for a more complete assessment is identified.

  3. Carbon coated stainless steel as counter electrode for dye sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Prakash, Shejale Kiran; Sharma, Rakesh K.; Roy, Mahesh S.; Kumar, Mahesh

    2014-10-01

    A new type of counter electrode for dye sensitized solar cells has been fabricated using a stainless steel sheet as substrate and graphite, graphene and multiwall carbon nanotubes as the catalytic material which applied by screen printing technique. The sheet resistances of the substrates and there influence on the dye sensitized solar cells has been studied. The fabricated counter electrodes i.e. SS-graphite, SS-graphene SS-MWCNT and SS-platinum were tested for their photovoltaic response in the form of dye sensitized solar cells.

  4. Broadband energy transfer to sensitizing dyes by mobile quantum dot mediators in solar cells

    PubMed Central

    Adhyaksa, Gede Widia Pratama; Lee, Ga In; Baek, Se-Woong; Lee, Jung-Yong; Kang, Jeung Ku

    2013-01-01

    The efficiency of solar cells depends on absorption intensity of the photon collectors. Herein, mobile quantum dots (QDs) functionalized with thiol ligands in electrolyte are utilized into dye–sensitized solar cells. The QDs serve as mediators to receive and re–transmit energy to sensitized dyes, thus amplifying photon collection of sensitizing dyes in the visible range and enabling up–conversion of low-energy photons to higher-energy photons for dye absorption. The cell efficiency is boosted by dispersing QDs in electrolyte, thereby obviating the need for light scattering1 or plasmonic2 structures. Furthermore, optical spectroscopy and external quantum efficiency data reveal that resonance energy transfer due to the overlap between QD emission and dye absorption spectra becomes dominant when the QD bandgap is higher than the first excitonic peak of the dye, while co–sensitization resulting in a fast reduction of oxidized dyes is pronounced in the case of lower QD band gaps. PMID:24048384

  5. Effect of unmodulated laser light on the nanostructure of a thin solid AD-1 azo dye film

    SciTech Connect

    Dubrovkin, A M; Ezhov, A A; Kozenkov, V M; Magnitskiy, Sergey A; Nagorskiy, Nikolay M; Panov, Vladimir I

    2010-06-23

    Exposure to light uniform in intensity and polarisation causes marked changes in the surface topography of a thin (320 nm) nanostructured AD-1 low molecular weight azo dye film. Linearly polarised incoherent light with a wavelength of 470 nm and intensity of 1 mW cm{sup -2} produces numerous teardrop-shaped hillocks of the order of 200 nm in radius over most of the film surface. (letters)

  6. Electrical characterization of dye sensitized nano solar cell using natural pomegranate juice as photosensitizer

    NASA Astrophysics Data System (ADS)

    Adithi, U.; Thomas, Sara; Uma, V.; Pradeep, N.

    2013-02-01

    This paper shows Electrical characterization of Dye Sensitized Solar Cell using natural dye, extracted from the pomegranate as a photo sensitizer and ZnO nanoparticles as semiconductor. The constituents of fabricated dye sensitized solar cell were working electrode, dye, electrolyte and counter electrode. ZnO nanoparticles were synthesized and used as semiconductor in working electrode. Carbon soot was used as counter electrode. The resistance of ZnO film on ITO film was found out. There was an increase in the resistance of the film and film changes from conducting to semiconducting. Photovoltaic parameters of the fabricated cell like Short circuit current, open circuit voltage, Fill factor and Efficiency were found out. This paper shows that usage of natural dyes like pomegranate juice as sensitizer enables faster and simpler production of cheaper and environmental friendly solar cell.

  7. High-efficiency dye-sensitized solar cells using ferrocene-based electrolytes and natural photosensitizers

    NASA Astrophysics Data System (ADS)

    Sönmezoğlu, Savaş; Akyürek, Cafer; Akin, Seçkin

    2012-10-01

    A new and promising dye-sensitized solar cell (DSSC) bilayer design was developed using an Fe2+/Fe3+ (ferrocene) liquid electrolyte and natural dyes extracted from Hypericum perforatum, Rubia tinctorum L. and Reseda luteola. The photovoltaic parameters controlling the device performance were then investigated. A DSSC based on quercetin dye displayed the most efficient solar to electricity conversion efficiency compared with other dyes with a maximum η value of 2.17%. Maximum overall conversion efficiencies under simulated sunlight that was comparable to natural photosynthesis were increased by 15%. The identification of appropriate additives for improving VOC without causing dye degradation may result in further enhancement of cell performance, making the practical application of such systems more suitable for achieving economically viable solar energy devices.

  8. Zinc-oxide-based nanostructured materials for heterostructure solar cells

    SciTech Connect

    Bobkov, A. A.; Maximov, A. I.; Moshnikov, V. A. Somov, P. A.; Terukov, E. I.

    2015-10-15

    Results obtained in the deposition of nanostructured zinc-oxide layers by hydrothermal synthesis as the basic method are presented. The possibility of controlling the structure and morphology of the layers is demonstrated. The important role of the procedure employed to form the nucleating layer is noted. The faceted hexagonal nanoprisms obtained are promising for the fabrication of solar cells based on oxide heterostructures, and aluminum-doped zinc-oxide layers with petal morphology, for the deposition of an antireflection layer. The results are compatible and promising for application in flexible electronics.

  9. Microscopic observation of dye molecules for solar cells on a titania surface.

    PubMed

    Koshiya, Shogo; Yamashita, Shunsuke; Kimoto, Koji

    2016-01-01

    The lateral distribution and coverage of Ru-based dye molecules, which are used for dye-sensitized solar cells (DSCs), were directly examined on a titania surface using high-resolution scanning transmission electron microscopy (STEM). The clean surface of a free-standing titania nanosheet was first confirmed with atomic resolution, and then, the nanosheet was used as a substrate. A single dye molecule on the titania nanosheet was visualized for the first time. The quantitative STEM images revealed an inhomogeneous dye-molecule distribution at the early stage of its absorption, i.e., the aggregation of the dye molecules. The majority of the titania surface was not covered by dye molecules, suggesting that optimization of the dye molecule distribution could yield further improvement of the DSC conversion efficiencies. PMID:27087005

  10. Microscopic observation of dye molecules for solar cells on a titania surface

    PubMed Central

    Koshiya, Shogo; Yamashita, Shunsuke; Kimoto, Koji

    2016-01-01

    The lateral distribution and coverage of Ru-based dye molecules, which are used for dye-sensitized solar cells (DSCs), were directly examined on a titania surface using high-resolution scanning transmission electron microscopy (STEM). The clean surface of a free-standing titania nanosheet was first confirmed with atomic resolution, and then, the nanosheet was used as a substrate. A single dye molecule on the titania nanosheet was visualized for the first time. The quantitative STEM images revealed an inhomogeneous dye-molecule distribution at the early stage of its absorption, i.e., the aggregation of the dye molecules. The majority of the titania surface was not covered by dye molecules, suggesting that optimization of the dye molecule distribution could yield further improvement of the DSC conversion efficiencies. PMID:27087005