Narrow band gap semiconductor materials were composited to a photoanode to improve its light response characteristics and the photoelectric conversion properties of dye-sensitized solar cells (DSSCs).The citric acid gel method was used to prepare the CoAl2O4 nanopowders and the X-ray diffraction spectra were utilized to analyze the effect of roasting temperature on crystal structures and particle sizes.Then,the surface morphology of CoAl2O4 was observed by transmission electron microcopy,the absorbances of CoAl2O4 nanopowders and CoAl2O4/TiO2 porous composite films were tested by UV-visible absorption spectroscopy and the band gaps of CoAl2O4 nanopowders were calculated.By using CoAl2O4/TiO2 composite films as the photoanode,the DSSC was prepared.The optical performance of the DSSC was tested by a solar simulator and a SourceMeter and the influence of doping CoAl2O4 on the photoelectric properties of a DSSC was investigated.The results show that the optimum roasting temperature of CoAl2O4 powders is 700 ℃ ; and its band gap energy is 1.69 eV,which means that it is a narrow band gap semiconductor material.Moreover,the performance of DSSC is the best and the conversion efficiency improves by 62％ when the amount of CoAl2O4 powder is 1％ (weight percentage).The stability of the CoAl2O4/TiO2 composite thin film cells is better than that of the pure TiO2 thin film cell.These results demondtrate that compositing CoAl2O4 to TiO2 can improve the conversion efficiencies of DSSCs.%采用向太阳电池光阳极中复合窄禁带半导体材料的方法来提高光阳极的光响应范围,以改善染料敏化太阳能电池的性能.用柠檬酸凝胶法制备CoAl2O4纳米粉体,并通过X-射线衍射光谱分析煅烧温度对CoAl2O4纳米粉体晶型及晶粒的影响规律；采用透射电镜观察CoAl2O4纳米粉体的表面形貌；通过紫外-可见吸收光谱分析CoAl2O4纳米粉体和CoAl2O4/TiO2复合多孔纳米薄膜的吸光度,并计算了CoAl2O4纳米粉体的禁带宽度.以CoAl2O4/TiO2复合薄膜为光阳极制备了染料敏化太阳电池(DSSC),应用太阳光模拟器及数字源表测试了DSSC的光电性能,分析了CoAl2O4的复合量对DSSC光电性能的影响规律.实验结果表明:CoAl2O4粉体的最佳烧结温度为700℃；CoAl2O4粉体的禁带宽度为1.69 eV,属于窄禁带半导体材料；当CoAl2O4的复合量为1％时,电池性能较好,转化效率提高了62％.另外,CoAl2O4/TiO2复合薄膜电池的稳定性比纯TiO2薄膜电池好.得到的结果说明向TiO2中复合CoAl2O4粉体可以提高电池的转化效率.
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