染料敏化太阳电池新型介孔碳对电极的制备及性能研究

以三嵌段共聚物F127为模板剂制备介孔碳,并用N2吸附和透射电子显微镜对介孔碳样品进行分析.所制备介孔碳材料的孔呈无序蠕虫状,平均孔径为6.8nm,比表面积为400m2/g.用介孔碳作为I(-)/I(-)3氧化还原反应的催化剂制备染料敏化太阳电池对电极,用电化学阻抗谱对介孔碳电极的催化活性进行了分析.介孔碳电极对I(-...     

磁控溅射制备染料敏化太阳能电池氮掺杂碳膜对电极

采用双极脉冲磁控溅射法制备氮掺杂碳膜并作为对电极应用在染料敏化太阳能电池(DSSC)中。研究了氮掺杂对碳膜的结构与性能的影响。用X射线光电子能谱(XPS)对氮掺杂碳膜进行薄膜表面元素分析,用四探针测试仪对氮掺杂碳膜的方块电阻进行测试,用扫描电镜对氮掺杂碳膜表面形貌进行分析。组装电池,用太阳光模拟器测试电池的光电转化率。研究结果表明,经过氮掺杂的碳膜,表面形貌致密,当N2的体积分数为30%时,薄膜中N元素含量为15.21%,薄膜的方块电阻为9.4Ω/□,电池的光电转化率为1.16%。     

Characteristics of dye-sensitized solar cells with surface-modified multi-walled carbon nanotubes as counter electrodes

A polystyrene-based functional block copolymer is employed as a surface modifier for multi-walled carbon nanotube (MWCNT) paste utilized in the fabrication of a MWCNT counter electrode (CE) in dye-sensitized solar cells (DSSCs). The surface modification of MWCNTs paste improves the dispersibility of MWCNTs, resulting in a facilitated fabrication of electrodes through the screen printing procedure, as evidenced by a lower viscosity and more homogeneous paste, as well as a more uniform MWCNT coating. Upon removing organic compounds from the paste through a thermal treatment procedure, the DSSC with the modified CE exhibits enhanced solar energy conversion efficiency (η) compared with that of the neat MWCNT CE. The behavior stems from an improvement in the overall redox reaction kinetics and the short-circuit current (J _sc) of the DSSC. The DSSC also exhibits an improved η value over an extended storage period, which demonstrates a successful combination of processability, performance, and stability of the DSSC achieved by using an optimum amount of surface modifier for MWCNTs.     

基于不同浓度铂对电极的染料敏化太阳能电池的性能研究

染料敏化太阳能电池对电极上用于催化的铂的浓度对电池的光电转换性能有重要的影响,特别是当光从对电极射入染料敏化太阳能电池(DSSC)时.制备了不同铂浓度对电极的电池,研究了光从对电极入射时,铂对内部阻抗、光吸收效率等的影响,优化出最佳的铂浓度.结果表明,10mmol/L为最佳对电极入射铂浓度,在一定浓度范围内,开路电压(...     

Aligned carbon nanotube sheets for the electrodes of organic solar cells

Aligned carbon nanotube sheets are developed as a new family of electrodes to fabricate dye-sensitized solar cells. The energy conversion efficiency of the resulting cell is higher than the randomly dispersed carbon nanotube film and comparable with the platinum. Novel and flexible solar cells can be easily made from such carbon nanotube sheets with high potentials.     

Large area dye-sensitized solar cells with titanium based counter electrode

Construction of dye-sensitized solar cell of large area using platinum sputtered titanium metal counter electrode is demonstrated. An impressive increase in the fill factor and consequently the efficiency compared to the conventional platinized conducting glass based counter electrodes result from very low sheet resistance of the titanium plate and a cell of active area 151 cm² with parallel silver collecting grids delivered an efficiency of 7.4%. The possibility of using this technique for commercial production of dye-sensitized solar cells was discussed giving details of fabrication procedure.     

染料敏化太阳电池中铂金对电极的制备及性能之比较

分别采用了3种不同的方法制备了用于染料敏化TiO2太阳电池的铂金对电极，并分别以此3种铂金对电极组装染料敏化太阳电池，对比、分析和探讨了它们对光电转化性能的影响。结果表明：采用纳米粒子电沉积法与电化学电镀法制备的铂金对电极，具有较高的催化活性，以这两种方法制备的铂金对电极组装的DSSCs获得较好的光电转化性能，电池的光电转化效率分别为6．40％和6．63％，且采用纳米粒子电沉积法制备的铂金对电极铂金含量较低；而采用热分解法制备的铂金对电极来组装的DSSCs获得的光电性能相对较低，电池效率为5．58％。     

染料敏化太阳能电池柔性对电极的研究进展

从柔性基体的选择,高聚物基底铂对电极的低温制备方法,金属基底铂对电极以及其它催化材料柔性对电极等几个方面介绍了染料敏化太阳能电池柔性对电极的研究现状,重点评述了高聚物基底铂对电极的低温制备技术,如磁控溅射真空镀铂、化学镀铂、电化学镀铂、雕版印刷、旋转涂布等,并就柔性对电极的未来发展方向进行了展望.     

不同炭材料对电极对染料敏化太阳能电池性能的影响

分别以石墨/活性炭/炭黑/碳纳米管为原料,采用丝网印刷技术制备染料敏化太阳能电池(DSSC)的对电极。分析比较了各原料的孔结构、比表面积及各原料制膜的方块电阻对组装电池性能的影响。结果表明,对于制备DSSC对电极的原料而言,孔尺寸要有一定的分布范围,孔形状要求口径大于或至少等于体径;比表面积并非越大越好,还应考虑其内部孔结构;制膜的方块电阻并非是影响电池性能的决定性因素。另外,原料的颗粒形状及排布方式也影响电池的性能。笔者以比表面积31.163 m.2g-1、方块电阻12.5Ω/□的碳纳米管所制碳膜组装的电池性能最佳,光电转化效率达5.87%。     

An improved polymer solar cell incorporating single-wall carbon nanotubes

We present an improved efficiency of polymer solar cell by incorporating single-wall carbon nanotubes (SWCNTs). A power conversion efficiency of 2.66% was achieved for the device with 0.125 wt% SWCNTs, which is 16% improvement over control device without SWCNTs, primarily due to the increase in the photocurrent and fill factor. The results reveal that SWCNTs serve as effective and additional electron pathways, facilitating the electron transport and improving the interface contact between active layer and electrode. The improved contact area was evidenced by the increased root-mean-square surface roughness as SWCNTs concentration increases. However, the increased peak-to-valley value also indicates the possibility of short circuit in device, thus the concentration of SWCNTs has to be optimized.     

CuI-Si heterojunction solar cells with carbon nanotube films as flexible top-contact electrodes

We report the fabrication of CuI-Si heterojunction solar cells with carbon nanotubes (CNTs) as a transparent electrode. A flexible CNT network was transferred onto the top of a polycrystalline CuI layer, making a conformal coating with good contact with the underlying CuI. The solar cells showed power conversion efficiencies in the range of 6% to 10.5%, while the efficiency degradation was less than 10% after the device was stored in air for 8 days. Compared with conventional rigid electrodes such as indium tin oxide (ITO) glass, the flexibility of the CNT films ensures better contact with the active layers and removes the need for press-contact electrodes. Degraded cells can recover their original performance by acid doping of the CNT electrode. Our results suggest that CNT films are suitable electrical contacts for rough materials and structures with an uneven surface.      

Highly conductive, transparent flexible films based on open rings of multi-walled carbon nanotubes

Open rings of multi-walled carbon nanotubes were stacked to form porous networks on a poly(ethylene terephthalate) substrate to form a flexible conducting film (MWCNT-PET) with good electrical conductivity and transparency by a combination of ultrasonic atomization and spin-coating technique. To enhance the electric flexibility, we spin-coated a cast film of poly(vinyl alcohol) onto the MWCNT-PET substrate, which then underwent a thermo-compression process. Field-emission scanning electron microscopy of the cross-sectional morphology illustrates that the film has a robust network with a thickness of ~ 175 nm, and it remarkably exhibits a sheet resistance of approximately 370 Ω/sq with ~ 77% transmittance at 550 nm even after 500 bending cycles. This electrical conductivity is much superior to that of other MWCNT-based transparent flexible films.     

Multi-walled carbon nanotubes as a new counter electrode for dye-sensitized solar cells

Airbrushed multi-walled carbon nanotube (MWNT) networks were investigated as a new counter electrode for dye-sensitized TiO2 photoelectrochemical solar cells. The structural and physical properties of the MWNTs were studied by various techniques including SEM, TEM, Raman, optical absorption, and electrochemical impedance spectroscopy (EIS). The MWNTs exhibited catalytic activity for the reduction of triiodide in the electrolyte as studied by EIS measurements. The performance of the dye-sensitized solar cells was improved by using MWNTs as counter electrodes. This observation is explained by the significantly increased contact area between the MWNT counter electrode and the electrolyte which facilitates efficient charge transportation in the solar cell. We demonstrated that the MWNTs are suitable for replacing expensive Pt electrodes for fabricating high efficiency dye-sensitized solar cells. The process used in this study is also technically attractive for large scale and economic production.     

表面活性剂改性的大孔径介孔炭对电极染料敏化太阳电池(英文)

以大孔径的介孔炭(MC)为催化层材料经低温热处理构建出炭对电极,着重探讨了在炭浆料中添加Triton X100对其组装的染料敏化太阳电池(DSCs)光电性能的影响,并引入分形维数(DF)用于定量评估炭膜形貌的差异。结果表明,当炭浆料中Triton X100的含量增加到0.1 mL(相应MC含量为0.6 g)时,DSCs的光电转换效率增加至5.65%,其值比活性炭对电极DSCs高46.5%,且达到Pt对电极DSCs的95.4%。Triton X100改性的介孔炭对电极的高性能归功于高品质的炭膜和介孔炭本身合理的孔结构(如大尺寸孔径和大比表面积等)。相对于未添加Triton X100的纯介孔炭对电极,Triton X100改性的介孔炭对电极具有分布更均匀的炭膜和更小的分形维数,是对电极欧姆串阻减小及相应器件效率改善的一个重要因素。     

TiO2-grafted multi-walled carbon nanotubes for dye-sensitized solar cells

Dye-Sensitized Solar Cells (DSSCs) comprised of TiO2 porous films with multi-walled carbon nanotubes (MWNT) were prepared at low temperature (150 degrees C). MWNT were incorporated to facilitate the fast electron transport resulting from metallic properties of carbon nanotubes. In order to enhance the effect of MWNT incorporation, TiO2-grafted MWNT (TiO2-MWNT) was synthesized which can increase the electron transport rate further due to proximity of TiO2 to MWNT The presence of TiO2 nanoparticles on the surface of MWNT was confirmed by electron microscopy and energy dispersive X-ray spectroscopy. As in the DSSCs prepared through high temperature sintering of photoanodes, the maximum content of MWNT incorporated into TiO2 was limited to 0.01 wt% relative to TiO2. TiO2 photoanodes including TiO2-grafted MWNT (TiO2-MWNT/P25) enhanced the cell efficiencies by ca. 28% and 14%, relative to TiO2 photoanodes without and with MWNT respectively, reaching the efficiency of 5.0%. Electrochemical impedance spectroscopy (EIS) was utilized to examine the effect of incorporation of TiO2 nanoparticles grafted to MWNT on the cell performance.     

Optimization of the cutting process of multi-wall carbon nanotubes for enhanced dye-sensitized solar cells

Dye-sensitized solar cells (DSSCs) were fabricated based on multi-wall carbon nanotube (MWCNT)-TiO₂ photo-anodes, which were prepared by the procedures of cutting MWCNTs and subsequent immobilization TiO₂ on MWCNTs. Through a detailed study, we found that cut-MWCNTs with proper ultrasonication time (2 h) and proper content (0.075%) resulted in 58 and 40% increase in short-circuit photocurrent and overall energy conversion efficiency, respectively, compared with that of a DSSC using only TiO₂ photo-anode. The enhancement of cut-MWCNTs for DSSC was attributed to the introduction of percolative conductive paths which facilitate the rapid electron transfer.     

Effects of mesoscopic poly(3,4-ethylenedioxythiophene) films as counter electrodes for dye-sensitized solar cells

Counter electrode coated with chemically polymerized poly(3,4-ethylenedioxythiophene) (PEDOT) in a dye-sensitized solar cell (DSSC) was studied. The surface morphology and the nature of I⁻/I₃⁻ redox reaction based on PEDOT film were investigated using Atomic Force Microscopy and Cyclic Voltammetry, respectively. The performance of the DSSCs containing the PEDOT coated electrode was compared with sputtered-Pt electrode. We found that the root mean square roughness decreases and conductivity increases as the molar ratio of imidazole (Im)/EDOT in the PEDOT film increases. The DSSC containing the PEDOT coated on fluorine doped tin oxide glass with Im/EDOT molar ratio of 2.0, showed a conversion efficiency of 7.44% compared to that with sputtered-Pt electrode (7.77%). The high photocurrents were attributed to the large effective surface area of the electrode material resulting in good catalytic properties for I₃⁻ reduction. Therefore, the incorporation of a multi-walled carbon nanotube (MWCNT) in the PEDOT film, coated on various substrates was also investigated. The DSSC containing the PEDOT films with 0.6 wt.% of MWCNT on stainless steel as counter electrode had the best cell performance of 8.08% with short-circuit current density, open-circuit voltage and fill factor of 17.00 mA cm⁻², 720 mV and 0.66, respectively.     

染料敏化太阳能电池的研究进展

综述了近年来关于染料敏化太阳能电池制备的研究状况,详细介绍了国内外关于二氧化钛薄膜、反电极、染料和电解质的设计思路及制备情况,并讨论了制备方法对太阳能电池性能的影响.     

Review on development of electrolytes for dye-sensitized solar cells

Since the prototype of a dye-sensitized solar cell(DSSC)was reported in 1991 by M. Gratzel,it has aroused intensive interest over the past decade due to its low cost and simple preparation procedure.The typical cell consists of a dye-coated mesoporous nanocrystalline TiO_2 film sandwiched between two transparent electroldes.A liquid electrolyte,traditionally containing the trioidide/iodide redox couple,fills the pores of the mesoporous nanocrystalline TiO_2 film and contacts the nanoparticles.Photoexcite...