染料敏化纳米晶太阳能电池用密封胶

染料敏化纳米晶太阳能电池(DSSC)因其制造成本远低于单晶硅和多晶硅太阳能电池,在石油资源紧张的现代备受瞩目,是继燃料电池之后新能源开发的又一热点。在实用化过程中,电解液的密封是一个至关重要又难于解决的关键技术。本文就电解液密封的技术要求介绍三键公司开发的紫外线固化型密封胶。     

染料敏化太阳能电池的研究进展

染料敏化太阳能电池（dye-sensitized solar cells,DSSC）由于工艺简单、价格便宜、转换效率高等优点而受到大量关注。本文介绍了染料敏化太阳能电池的基本结构和工作原理,综述了染料敏化太阳能电池的研究现状,论述了光阳极上半导体薄膜的制备、改性方法;阐述了敏化染料和氧化还原电解质的要求、特点和分类。指出高性能半导体薄膜、光谱响应宽稳定性好的敏化染料以及高效全固态电解质的研发与应用是今后的主要研究方向。     

Triphenylamine-based dyes for dye-sensitized solar cells

A novel, soluble, perylene oligomeric diimide dye, termed EOPPI was synthesized in high yield; for comparison, a small dye molecule, termed EOPDI, was also synthesized; both products readily dissolved in a wide range of organic solvents. The compounds were characterized using NMR, IR, MS, UV–vis, MS, GC–MS, HRMS, DSC, TGA, elemental analysis and cyclic voltammetry. The average molecular mass of EOPPI was 4460, its intrinsic viscosity was 0.3 dl g⁻¹ in m-cresol at 20 °C. The band gap energy (E_g), LUMO and HOMO energy values were 2.25, −3.78 and −6.03 eV for the small dye molecule and 2.24, −3.85 and −6.09 eV for the oligomer, respectively. The temperatures at which the monomer and oligomer began to lose mass were 300 and 375 °C, respectively. The oligomer showed concentration-dependent color tunability.     

染料敏化太阳能电池非铂对电极研究进展

对电极作为染料敏化太阳能电池（dye-sensitized solar cell,DSSC）的重要组成部分,对电极材料性能的好坏直接影响着染料敏化太阳能电池的光电转化效率。最常使用的对电极电催化材料是贵金属铂,而铂十分稀少而且价格昂贵,并且铂很容易被碘电解液腐蚀,不利于染料敏化太阳能电池的产业化发展。本文重点综述了2010年以来染料敏化太阳能电池非铂对电极的研究成果,简要说明了对电极在染料敏化太阳能电池中的作用,详细介绍了非铂金属、碳材料、导电聚合物和无机化合物等对电极材料,分析了各类非铂对电极材料的特点、制备工艺、发展前景、优缺点和改进措施。最后提出,继续开发各种成本低、原料易得以及稳定高效的新型非金属对电极材料仍是今后染料敏化太阳能电池研究的一个重要方向。     

Solid-state dye-sensitized hierarchically structured ZnO solar cells

A novel solid-state hierarchically structured ZnO dye-sensitized solar cell (DSC) was assembled by using TiO₂ as filler in polyethylene oxide (PEO)/polyethylene glycol (PEG) electrolytes and ZnO nanocrystalline aggregates as photoanode film. Under optimized composite polyelectrolyte containing PEO/oligo-PEG/TiO₂/LiI/I₂ the photovoltaic performance of the solid-state ZnO DSCs was significantly better, with an overall conversion efficiency (η) of 1.8% under irradiation of 100 mW/cm², which was higher than those of the cells with PEO/TiO₂/LiI/I₂ (η = 1.1%) or PEO/oligo-PEG/LiI/I₂ electrolyte (η = 1.5%). Further, the hierarchically structured ZnO-based cell showed a higher η value of 2.0% under 60 mW/cm² radiation. The morphologies, ionic conductivity of three different composite electrolytes and their performance to the DSCs were also studied by FESEM, I–V data, IPCE and EIS.     

Full-photonic-bandgap structures for prospective dye-sensitized solar cells

The photonic bands of various TiO₂ photonic crystals filled with acetonitrile were investigated with the perspective for application to dye-sensitized solar cells. Finite-difference time-domain methods revealed that three-dimensional (3D) photonic crystals with diamond-log and inverse-diamond-log structures composed of TiO₂ and an electrolyte had full photonic band gaps under certain conditions. The quality factor of the band gap and the electrolyte filling factor of the structures were optimized. Moreover, with the consideration for easy fabrication of such photonic crystals, two-dimensional (2D) photonic crystals, i.e., TiO₂ slabs with square holes filled with electrolytes, were also investigated. Two-dimensional structures that have a full photonic band gap were also discovered. These discoveries may lead to early electrochemical applications of dye-sensitized photonic-crystal electrodes.     

Graphene-based counter electrode for dye-sensitized solar cells

Graphene nanosheets (GNs) were synthesized and used as a substitute for platinum as counter-electrode materials for dye-sensitized solar cells (DSSCs). The as-synthesized GNs were dispersed in a mixture of terpineol and ethyl cellulose. GN films were screen-printed on fluorine-doped tin oxide (FTO) slides using the formed GN dispersions. GN counter-electrodes were produced by annealing the GN films at different temperatures. The annealed GN films revealed an unusual 3D network structure. Structural and electrochemical properties of the formed GN counter-electrodes were examined by field emission scanning electron microscopy, Raman spectroscopy and electrochemical impedance spectroscopy. It was found that the annealing temperature of GN materials played an important role in the quality of the GN counter-electrode and the photovoltaic performance of the resultant DSSC. The grown DSSCs with graphene-based counter-electrodes exhibited a conversion efficiency high up to 6.81%.     

Electrodeposited Pt for cost-efficient and flexible dye-sensitized solar cells

Pt electrodes were prepared by direct and pulse current electrodeposition for use as counter electrodes in dye-sensitized solar cells. Scanning electron microscope and transmission electron microscope images confirmed the formation of uniform Pt nanoclusters of ∼40 nm composed of 3 nm nanoparticles, when the pulse current electrodeposition method was used, as opposed to the dendritic growth of Pt by the results from direct current electrodeposition. By applying pulse electrodeposited Pt which has a 1.86 times higher surface area compared to direct current electrodeposited Pt, short-circuit current and conversion efficiency were increased from 10.34 to 14.11 mA/cm² and from 3.68 to 5.03%, respectively. In addition, a flexible solar cell with a pulse current electrodeposited Pt counter electrode with a conversion efficiency of 0.86% was demonstrated.     

Multi-alkylthienyl appended porphyrins for efficient dye-sensitized solar cells

Four porphyrin dyes, incorporating multi-alkylthienyl appended porphyrins as the electron donor, the 2-cyanoacrylic acid as the electron acceptor, and different π-conjugated spacer, have been synthesized for dye-sensitized solar cells (DSSCs). All the porphyrin dyes studied in this work exhibit red-shifted and broadened electronic spectra respect to the reference P_Zn as expected. By the introduction of thienyl groups at the meso-positions, the energy level of E_ox (excited-state oxidation potentials) is significantly shifted to the positive compared with the reference P_Zn, indicating a decreased HOMO-LUMO gap. The highest power conversion efficiency of the four dyes based on DSSCs reached 5.71% under AM 1.5 G irradiation.     

Electronically coupled porphyrin-arene dyads for dye-sensitized solar cells

An acetylene-linked porphyrin-perylene anhydride and an acetylene-linked porphyrin-naphthalic anhydride have been synthesized; the highly conjugated acetylenic bridge in these porpyrins efficiently mediates electronic interaction between the porphyrin and perylene units to extend the π-conjugation of the porphyrin dye and to cause both broadening and red shifts of both the Soret and Q absorption bands. This condition is a useful feature for efficient dye-sensitized solar cell applications. The optical, electrochemical and photovoltaic properties of the new linked anhydrides show that the HOMO–LUMO gap decreased upon extension of π-conjugation, indicating a strong electronic coupling between the porphyrin and the perylene or naphthalene unit.     

Multi-alkylthienyl appended porphyrins for efficient dye-sensitized solar cells

Four porphyrin dyes, incorporating multi-alkylthienyl appended porphyrins as the electron donor, the 2-cyanoacrylic acid as the electron acceptor, and different π-conjugated spacer, have been synthesized for dye-sensitized solar cells (DSSCs). All the porphyrin dyes studied in this work exhibit red-shifted and broadened electronic spectra respect to the reference P_Zn as expected. By the introduction of thienyl groups at the meso-positions, the energy level of E_ox (excited-state oxidation potentials) is significantly shifted to the positive compared with the reference P_Zn, indicating a decreased HOMO–LUMO gap. The highest power conversion efficiency of the four dyes based on DSSCs reached 5.71% under AM 1.5 G irradiation.     

Electronically coupled porphyrin-arene dyads for dye-sensitized solar cells

An acetylene-linked porphyrin-perylene anhydride and an acetylene-linked porphyrin-naphthalic anhydride have been synthesized; the highly conjugated acetylenic bridge in these porpyrins efficiently mediates electronic interaction between the porphyrin and perylene units to extend the π-conjugation of the porphyrin dye and to cause both broadening and red shifts of both the Soret and Q absorption bands. This condition is a useful feature for efficient dye-sensitized solar cell applications. The optical, electrochemical and photovoltaic properties of the new linked anhydrides show that the HOMO-LUMO gap decreased upon extension of π-conjugation, indicating a strong electronic coupling between the porphyrin and the perylene or naphthalene unit.     

染料敏化太阳能电池中凝胶电解质的研究进展

简单介绍了凝胶电解质的概念、分类以及凝胶电解质染料敏化太阳能电池制作过程,着重对有机小分子凝胶电解质、聚合物凝胶电解质和无机纳米粒子凝胶电解质3种不同凝胶电解质研究进展进行了综述.     

Novel fluoranthene dyes for efficient dye-sensitized solar cells

Three, novel, fluoranthene-based dyes, 2-cyano-3-(5-(7,12-diphenylbenzo[k]fluoranthen-3-yl)thiophen-2-yl)acrylic acid, 2-(5-((5-(7,12-diphenylben-zo[k]fluoranthen-3-yl)thiophen-2-yl)methylene)-4-oxo-2-thioxothiazolidin-3-yl)acetic acid and 2-cyano-3-(4-(2-(7,12-diphenylbenzo[k]fluoranthen-3-yl)ethynyl) phenyl) acrylic acid, were synthesized for application as sensitizers in dye-sensitized solar cells. In each dye, the 7,12-diphenyl-benzo[k]fluoranthene moiety acted as electron donor with phenyl and thiophene units as electron spacers and carboxylic acid as electron acceptor. Tuning of the HOMO and LUMO energy levels was conveniently accomplished by changing the spacer and acceptor moiety, as confirmed using electrochemical measurements. Maximum solar energy:electricity conversion efficiency was 4.4% under AM 1.5 solar simulator (100 mW cm^?2) for 2-cyano-3-(5-(7,12-diphenylbenzo[k]fluoranthen-3-yl)thiophen-2-yl)acrylic acid. The results suggest that dyes based on fluoranthene donor are promising candidates for high performance, dye-sensitized solar cells.     

染料敏化太阳能电池的进展及前景

国际太阳能光伏产业近年来发展迅猛,随着中国太阳能光伏发电技术的不断提高,为产业发展开拓了新思路,市场前景日趋广阔。笔者简明地介绍了染料敏化纳米薄膜太阳能电池的结构和原理;综合评述了染料敏化太阳能电池的研究进展,总结了染料敏化纳米薄膜太阳能电池的关键材料:(1)染料(2)电极材料(3)电解质等的研究现状和发展趋势,指出了各自存在的问题,提出了部分解决设想,并对其工业化前景进行了探讨。     

Plasmon-enhanced quasi-solid-state dye-sensitized solar cells with metal@Dendron nanoparticles

We have investigated the effects of localized surface plasmons (LSPs) on the performance of quasi-solid-state dye-sensitized solar cells (DSSCs). Ag and Au nanoparticles (NPs) were prepared by photoreduction in the presence of generation 5 polyester hydroxyl acetylene bis(hydroxymethyl)propanoic acid dendrons (Dendron) as a stabilizer. The plasmon-enhanced DSSCs were achieved by incorporating metal@Dendron NPs into TiO₂ photoanodes. The presence of dendrons prevents the photoelectrons from recombining on the surface of TiO₂ semiconductor and improves the stability of metal NPs. With the addition of Ag@Dendron NPs, the photocurrent and the power conversion efficiency of quasi-solid-state DSSCs increased due to the LSP effect of metal NPs and the barrier effect of dendron, which were confirmed by the increased incident photon-to-photocurrent efficiency and by electrochemical impedance spectroscopy analysis.     

First-principles modeling of dye-sensitized solar cells: challenges and perspectives

Since dye-sensitized solar cells (DSSCs) appeared as a promising inexpensive alternative to the traditional silicon-based solar cells, DSSCs have attracted a considerable amount of experimental and theoretical interest. In contrast with silicon-based solar cells, DSSCs use different components for the light-harvesting and transport functions, which allow researchers to fine-tune each material and, under ideal conditions, to optimize their overall performance in assembled devices. Because of the variety of elementary components present in these cells and their multiple possible combinations, this task presents experimental challenges. The photoconversion efficiencies obtained up to this point are still low, despite the significant experimental efforts spent in their optimization. The development of a low-cost and efficient computational protocol that could qualitatively (or even quantitatively) identify the promising semiconductors, dyes, and electrolytes, as well as their assembly, could save substantial experimental time and resources. In this Account, we describe our computational approach that allows us to understand and predict the different elementary mechanisms involved in DSSC working principles. We use this computational framework to propose an in silico route for the ab initio design of these materials. Our approach relies on a unique density functional theory (DFT) based model, which allows for an accurate and balanced treatment of electronic and spectroscopic properties in different phases (such as gas, solution, or interfaces) and avoids or minimizes spurious computational effects. Using this tool, we reproduced and predicted the properties of the isolated components of the DSSC assemblies. We accessed the microscopic measurable characteristics of the cells such as the short circuit current (J(sc)) or the open circuit voltage (V(oc)), which define the overall photoconversion efficiency of the cell. The absence of empirical or material-related parameters in our approach should allow for its wide application to the optimization of existing devices or the design of new ones.     

A flexible carbon counter electrode for dye-sensitized solar cells

A pure carbon counter electrode (CE) for dye-sensitized solar cells (DSCs), has been fabricated using an industrial flexible graphite sheet as substrate and activated carbon as the catalytic material. The CE shows very low series resistance (Rs) and charge-transfer resistance (Rct) by combining the high conductivity of the flexible graphite with the high catalytic property of activated carbon. The Rs and Rct for the CE are respectively only a quarter and two-thirds of those for a platinized fluorine-doped tin oxide glass (Pt/FTO). DSCs with cell areas of 0.15 and 1 cm² fabricated with this CE show higher solar-to-electricity conversion efficiencies. The respective values are 6.46% and 5%, compared with 6.37% and 2.91% for the Pt/FTO based devices.     

Solid-state dye-sensitized ZnO solar cells prepared by low-temperature methods

Solid-state dye-sensitized solar cells based on highly porous ZnO films prepared by template-assisted electrodeposition as electron collector, the indoline dye D149 as sensitizer and CuSCN as hole collector have been prepared using three different methods, namely impregnation with saturated CuSCN solution, successive ionic layer adsorption and reaction (SILAR) and electrodeposition, for filling the pores in the ZnO with CuSCN. The highest pore filling and the highest conversion efficiency of 0.46% were achieved with the impregnation method, while SILAR led to a very low pore filling, causing very low photocurrents, and electrodeposition led to short-circuiting between the CuSCN and the conducting substrate of the ZnO sample despite the presence of a compact ZnO bottom layer between the porous ZnO layer and the conducting layer, causing very low open-circuit voltages.     

Plastic-polymer composite electrolytes for solid state dye-sensitized solar cells

Three types of alkyl-substituted poly(N-alkyl-1-vinyl-imidazolium) iodides were synthesized and plasticized using succinonitrile as a solid plasticizer to develop a series of novel solvent-free plastic-polymer composite electrolytes. All these electrolytes appeared as a soft solid at room temperature and became sticky gel state at high temperature of 100 °C. Among the as-prepared plastic-polymer electrolytes, the SCN-PMVII (succinonitrile-poly(1-vinyl-3-methylimidazolium) iodide) electrolytes with a SCN content of 40-60 wt.% showed a room temperature conductivity of 1.0-1.6 mS cm⁻¹and a photoconversion efficiency of >4.1%, which are comparable to those observed from liquid organic carbonate electrolyte and the DSSCs using the liquid electrolyte at the same experimental conditions. Also, the DSSCs assembled with the SCN-PMVII electrolytes maintained their photoconversion efficiency very steadily during aging test of 50 days despite of being placed at 40 °C under 1 sun illumination or stored at 60 °C in an oven. Since these plastic-polymer electrolytes are solvent-free, highly conductive and electrochemically compatible, it is possible to use this type electrolyte for development of practical DSSCs.