ZnO纳米四脚状阵列电极染料敏化太阳能电池

采用化学气相沉积(CVD)法制备了不同尺寸的四脚状纳米ZnO和ZnO纳米棒。采用X射线粉末衍射(XRD)、扫描电子显微镜(SEM)对纳米ZnO的晶型结构和形貌进行表征,研究结果表明CVD法制备的四脚状纳米ZnO具有三维空间结构,其最小平均臂宽约为70nm,臂长约300nm,制备的纳米棒直径约为84nm,长约2μm,且都为六方纤锌矿晶型结构。将ZnO纳米四脚状及纳米棒利用滚涂法在FTO导电玻璃上形成ZnO光阳极,经N719染料敏化后组装成染料敏化太阳能电池,光电性能结果表明,染料敏化小尺寸的四脚状纳米ZnO太阳能电池光电转换效率(η=1.88%)高于染料敏化大尺寸的四脚状纳米ZnO太阳能电池光电转换效率(η=1.18%),远高于染料敏化ZnO纳米棒太阳能电池的光电转换效率(η=0.7%)。     

后续的KOH腐蚀对ZnO纳米棒阵列及性能的影响

采用化学沉积和KOH腐蚀结合的方法,在FTO导电玻璃上制备了ZnO纳米棒阵列。用XRD、SEM、I-V曲线对ZnO纳米棒阵列的结构和性能进行了表征。结果表明:ZnO纳米棒为单晶,属于六方纤锌矿结构。后续的KOH腐蚀有利于ZnO纳米阵列形貌的改变及光电性能的提高,将ZnO纳米棒阵列作为光阳极制备染料敏化太阳能电池,被KOH腐蚀后的ZnO纳米棒阵列的光电转换效率(η)、短路电流(Jsc)、开路电压(Voc)分别达到1.2%、0.006A/cm2、0.557V,与未被KOH腐蚀的ZnO纳米棒相比,光电转换效率提高了1.05%。     

金红石型TiO2纳米棒的制备及其在染料敏化太阳电池中的应用

采用十二烷基苯磺酸钠表面活性剂(DBS)辅助水热法合成TiO2纳米材料,XRD和TEM测试表明,不含DBS的TiO2溶胶水热处理后得到10~20nm锐钛矿型TiO2纳米颗粒;添加DBS后,生成了金红石型TiO2纳米棒.虽然金红石型TiO2纳米棒光电极的染料吸附性能和光电性能均不如锐钛矿型TiO2纳米颗粒光电极,但金红石型TiO2纳米棒漫反射性能较高.可用其制备具有光电转换性能的反射层,这种新型反射层使染料敏化太阳能电池光电转换效率提高了26.14%,而含Ti-nanoxide 300大颗粒TiO2构成的反射层仅能使电池光电转换效率提高11.04%.这种差异的根源在于金红石型TiO2纳米棒不仅具有散射光能力,其本身还可吸附染料进行光电转换.随着反射层厚度的增加,电池短路电流逐步提高.而不吸附染料且无光电转换能力的Ti-nanoxide 300传统反射层则没有这种功能.     

SrCO_3/TiO_2复合薄膜太阳能电池的性能研究

采用丝网印刷法制备了SrCO3/TiO2复合薄膜电极;组装电池,研究了复合电极的光电性能。结果表明:敏化SrCO3/TiO2复合薄膜电极太阳能电池的短路电流密度、开路电压和填充因子比敏化TiO2电极电池均有增加,总的光电转换效率从3.01%提高到了3.53%,增加了17.3%。另外紫外光谱表明,SrCO3/TiO2复合薄膜电极吸附更多的染料。电化学阻抗谱研究表明,SrCO3/TiO2复合薄膜电极相对于空白TiO2电极有更小的阻抗,有利于电子在薄膜中的传输,提高了太阳能电池的性能。     

鸭跖草色素敏化TiO_2纳米管太阳能电池的研究

以高度有序TiO2纳米管阵列作为光阳极,鸭跖草色素作为敏化剂制备了天然染料敏化太阳能电池。阳极氧化6h制备的TiO2纳米管作为电极的电池的光电转换效率约达0.52%,短路电流为1.53mA/cm2。比较不同管长TiO2纳米管阵列对电池的光电性能的影响。利用紫外-可见光光谱仪研究鸭跖草色素的光吸收性能。利用电化学阻抗谱分析电池的界面阻抗。研究表明适当提高TiO2纳米管长度可以有效提高天然染料敏化太阳能电池的光电性能。     

Zn/纳米棒阵列ZnO/聚噻吩复合电极的制备及光电化学性质

使用简单的水热法在锌片上生长ZnO纳米棒阵列,并用电化学共聚制备了ZnO纳米棒阵列与聚噻吩(Zn/ZnO/PTH)复合膜。通过X射线衍射(XRD)、扫描电子显微镜(SEM)等手段对ZnO的结构和形貌进行表征,XRD结果表明产物为六方纤锌矿型ZnO。SEM结果表明,在垂直锌片方向生长了包括纳米棒、纳米片、纳米线的表面光滑的ZnO纳米阵列,其中以纳米棒为主,其直径为30～100nm,长度1μm。用光电流作用谱、光电流-电势图研究了Zn/ZnO/PTH电极的光电转换性质。结果表明,PTH修饰ZnO/Zn电极可使光电流产生波长发生明显红移,使其光电转换效率提高了4倍,填充因子FF=33%,光电转换效率η=1.25%。     

二氧化钛有序纳米阵列染料敏化太阳能电池光阳极的研究进展

介绍了染料敏化太阳能电池(DSSC)的结构和基本原理,综述了近年来作为DSSC光阳极的TiO2纳米管、纳米线、纳米棒阵列的制备工艺进展,重点介绍了阳极氧化法制备纳米管和水热法制备纳米线和纳米棒.阐述了通过改进TiO2纳米管提高DSSC效率的几种途径,包括优化纳米管的尺寸、改善纳米管的输运性能、在透明基板上生长纳米管、对纳米管进行表面修饰等.最后展望了TiO2纳米阵列DSSC的研究方向.     

利用有机介质丝网印刷技术制备TiO2纳晶电极

在水热法制备TiO2胶体的基础上,加入松油醇、聚丙烯酸酯、Tx-100、乙基纤维素组成浆液,利用丝网印刷技术制备了染料敏化纳晶多孔TiO2薄膜电极.在光强为100mW/cm2的条件下,TiO2电极显示了良好的光电化学性能,由介孔TiO2电极组装的染料敏化太阳能电池的光电转换效率可达6.9%.     

聚苯乙烯和聚乙二醇对TiO2薄膜微观结构及DSSC性能的影响

用水热法制备了多孔TiO2光电薄膜;分析了聚苯乙烯和聚乙二醇对纳米TiO2晶体薄膜微观结构的影响;用紫外-可见-近红外分光光度计和场发射扫描电镜对纳米TiO2薄膜进行了表征;并对组装的染料敏化太阳能电池进行了光电性能测试,发现用聚苯乙烯处理后的TiO2薄膜提高了染料敏化太阳能电池(DSSC)的开路电压、短路电流密度、填充因子和光电转换效率.     

敏化剂修饰纳米晶TiO2多孔膜电极的光电化学行为

在TiO2纳米晶多孔膜电极上,修饰了合成的RuL2(SCN)2(L＝2,2′-bipyridine-4,4′-dicarboxylic acid)及聚苯胺,用光电化学方法研究了该纳米晶TiO2/敏化剂多孔膜电极的光电转换机理,并比较了两类敏化复合电极的光电转换效能.用染料或聚苯胺修饰纳米晶多孔膜电极后,可使该复合电极在可见光区吸收增加,光电流增强,且起始波长红移至＞600 nm,从而提高了宽禁带半导体电极的光电转换效率.     

染料敏化太阳电池CuAl2O4/TiO2光阳极制备及性能

采用柠檬酸法制备了尖晶石型纳米晶CuAl2O4,将其添加到P25(degussa,TiO2)中,制备成CuAl2O4/TiO2薄膜光阳极,并组装成染料敏化太阳电池(DSSC),对其光电性能进行表征。结果表明:CuAl2O4的加入,电池性能得到提高;当CuAl2O4含量为2%(质量分数)时,与纯TiO2薄膜光阳极相比,光电转化效率提高了39.1%。     

Photocurrent-voltage of a dye-sensitized nanocrystalline TiO2 solar cells influenced by N719 dye adsorption properties

Titanium particles of single-phase anatase nanocrystallites were prepared by the hydrolysis of titanium tetraisopropoxide. A dye-sensitized solar cell (DSSC) was fabricated by adsorbing cis-bis(isothiocyanato)bis(2,2'-bipyridyl-4,4'-dicarboxylato)-ruthenium(II)bis-tetrabutylammonium dye (N719) onto TiO2 film. The samples were characterized by XRD, TEM, FE-SEM, AFM, and Brunauer-Emmett-Teller (BET) analysis. The influence of the acetic acid treatment of TiO2 electrode with different concentrations on the photovoltaic performance of DSSC was investigated. It was found that DSSC had better photoelectric performance when the TiO2 electrode was treated by acetic acid of 0.5 M. An equivalent circuit analysis using the one-diode model was used to evaluate the influences of adsorption quantity and acetic acid treatment on the energy conversion efficiency of DSSC. A nonlinear least-square optimization method was used to determine five model parameters.     

Enhancement of photovoltaic performance in dye-sensitized solar cells with the spin-coated TiO2 blocking layer

The TiO2 thin film layers were introduced with the spin-coating method between FTO electrode and TiO2 photoanode in dye sensitized solar cell (DSSC) to prevent electron back migration from the FTO electrode to electrolyte. The DSSC containg different thickness of TiO2 thin film (10-30, 40-60 and 120-150 nm) were prepared and photovoltaic performances were analysed with /-Vcurves and electrochemical impedance spectroscopy. The maximum cell performance was observed in DSSC with 10-30 nm of TiO2 thin film thickness (11.92 mA/cm2, 0.74 V, 64%, and 5.62%) to compare with that of pristine DSSC (11.09 mA/cm2, 0.65 V, 62%, and 4.43%). The variation of photoelectric conversion efficiency of the DSSCs with different TiO2 thin film thickness was discussed with the analysis of crystallographic and microstructural properties of TiO2 thin films.     

Fabrication and characterization of photoelectrode thin films with different morphologies of TiO2 nanoparticles for dye-sensitized solar cells

This study deals with the fabrication of three different morphologies of TiO2 nanoparticles to fabricate two-layer photoelectrode thin film for dye-sensitized solar cells (DSSC). The four different TiO2 morphologies are titania nanotubes (Tnt), TiO2 nanoparticles (H220), TiO2 nanoparticle (SP) and commercial DP-25 nanoparticles (P-25). To prepare the thin films of the photoelectrodes, the first layer is coated by H220 TiO2 nanoparticles, and the second is coated by 3 kinds of materials optimally proportionally mixed - P25, SP and Tnt. The photoelectric conversion efficiency of DSSCs with photoelectrodes fabricated using H220 reached 6.31%. Finally, the TiO2 nanaomaterials with four different morphologies were used to prepare a two layer photoelectrode with the structure of H220/P25-Tnt-SP which was combined with a Pt counter electrode to assemble DSSCs. These DSSCs had photoelectric conversion efficiencies of as high as 7.47%.     

Surface modified TiO2 nanostructure with 3D urchin-like morphology for dye-sensitized solar cell application

Three-dimensional (3D) urchin-like rutile TiO2 powders were synthesized by a mild hydrothermal method without any templates. An individual urchin-like TiO2 powder consists of self-assembled nanorods with a length of about 150 nm and width of about 10 nm. Additionally, the urchin-like TiO2 nanopowders were coated with an ultra-thin ZnO layer in order to modify the surface properties of the nanopowders, and the ZnO layer was confirmed by high-resolution transmission electron microscopy (HRTEM) and X-ray photoelectron spectroscopy (XPS) analysis. The ZnO-modified TiO2 was used as a photoelectrode of a dye-sensitized solar cell (DSSC) and the solar cell performances were investigated. In comparison with bare TiO2, ZnO-modified TiO2 improved the photovoltaic performances, i.e., energy conversion efficiency, open circuit voltage, and short circuit current were increased. The higher DSSC performance of ZnO-modified TiO2 was attributed to its higher dye loading and lower charge recombination rate.     

Application of TiO2 nanoparticles coated multi-wall carbon nanotube to dye-sensitized solar cells

This study uses the sol-gel method to prepare TiO2 nanoparticle, and further applies TiO2 nanoparticle coating on the surface of the multi-wall carbon nanotube (MWCNT). As a result, TiO2-CNT composite nanoparticles are prepared to serve as photoelectrode material in dye-sensitized solar cell (DSSC). First, after acid treatment of MWCNT is used to remove impurities. Then, the sol-gel method is employed to prepare TiO2-CNT composite nanopowder. X-ray diffraction (XRD) pattern shows that after the TiO2 in TiO2-CNT composite nanopowder has been thermally treated at 450 degrees C, it can be completely changed to anatase phase. Furthermore, as shown from the SEM image, TiO2 has been successfully coated on CNT. The photoelectrode of DSSC is prepared using the electrophoretic deposition method (EPD) to mix the Degassa P25 TiO2 nanoparticles with TiO2-CNT powder for deposition on the indium tin oxide (ITO) conductive glass. After secondary EPD, a thin film of TiO2/CNTs with thickness 17 microm can be acquired. For the prepared TiO2-CNT composite nanoparticles, since MWCNT can increase the short-circuit current density of DSSC, the light-to-electricity conversion efficiency of DSSC can be effectively increased. Experimental results show that the photoelectric conversion efficiency of DSSC using CNT/TiO2 photoelectrode and N719 dye is increased by 41% from the original 3.45% to 4.87%.     

方酸菁功能材料修饰纳米晶TiO2薄膜电极的光电转换性能研究

考察了三种方酸菁染料修饰的米晶ＴｉＯ２薄膜电极表面应用于光电化学太阳能电池进行光电转换的情况,发现它们的光电化学性能参数按照Ｓｑ３〉Ｓｑ２〉Ｓｑ１的顺序,随着染料在纳米晶ＴｉＯ２上吸附力的增强而提高,其中,Ｓｑ３的光电转换效率为２．１７％,它在６５０ｎｍ处的最高单色光光电流效率ＩＰＣＥ值达到６．２％,表明方酸菁是一类优良的光电转换功能材料。     

Effect of MWCNT Inclusion in TiO2 Nanowire Array Film on the Photoelectrochemical Performance

Rutile TiO2 nanowire array films with multi-walled carbon nanotube(MWCNT) inclusion perpendicularly grown on fluorine-doped tin oxide(FTO) substrate were prepared by a facile hydrothermal method.The absorption edges of the TiO2 nanowire array films are blue-shifted with increasing MWCNT content.The resistance of the TiO2 nanowire array film is decreased by MWCNT inclusion.The optimum TiO2 /MWCNT molar ratio in the feedstock is 1:0.1.For the TiO2 nanowire array film with MWCNT inclusion served as electrode in dye-sensitized solar cell(DSSC),an overall 194% increase of photoelectric conversion efficiency has been achieved.     

Fabrication of 3D interconnected porous TiO2 nanotubes templated by poly(vinyl chloride-g-4-vinyl pyridine) for dye-sensitized solar cells

Porous TiO(2) nanotube arrays with three-dimensional (3D) interconnectivity were prepared using a sol-gel process assisted by poly(vinyl chloride-graft-4-vinyl pyridine), PVC-g-P4VP graft copolymer and a ZnO nanorod template. A 7 μm long ZnO nanorod array was grown from the fluorine-doped tin oxide (FTO) glass via a liquid phase deposition method. The TiO(2) sol-gel solution templated by the PVC-g-P4VP graft copolymer produced a random 3D interconnection between the adjacent ZnO nanorods during spin coating. Upon etching of ZnO, TiO(2) nanotubes consisting of 10-15 nm nanoparticles were generated, as confirmed by wide-angle x-ray scattering (WAXS), energy-filtering transmission electron microscopy (EF-TEM) and field-emission scanning electron microscopy (FE-SEM). The ordered and interconnected nanotube architecture showed an enhanced light scattering effect and increased penetration of polymer electrolytes in dye-sensitized solar cells (DSSC). The energy conversion efficiency reached 1.82% for liquid electrolyte, and 1.46% for low molecular weight (M(w)) and 0.74% for high M(w) polymer electrolytes.     

TiO2/PEN表面改性对柔性DSSC性能的影响

对于柔性DSSC的透明光阳极而言,在低温下制备出结晶性高、颗粒间结合性能良好的TiO₂薄膜是其获得优异光电性能的关键。本文通过对比三种不同浆料添加剂(盐酸、乙二醇乙醚、小颗粒凝胶)对DSSC光电性能的影响,发现小颗粒凝胶的加入可以显著提高器件的光电性能。在此基础上,优化了小颗粒凝胶添加量及退火工艺,得出了最佳制备工艺条件,最终获得短路电流密度为8.14 mA/cm²、填充因子为67.9%、光电转化效率为4.1%的DSSC。进一步研究表明,小颗粒凝胶的加入一方面可以增强TiO₂颗粒之间的连接,从而提高TiO₂的成膜质量;另一方面可以增加TiO₂薄膜对光的散射,从而提高电池的吸光率。