CuInS2量子点敏化纳米TiO2太阳电池的界面电子复合机理研究

项目名称： CuInS2量子点敏化纳米TiO2太阳电池的界面电子复合机理研究

项目编号： No.21073193

项目类型： 面上项目

立项/批准年度： 2011

项目学科： 金属学与金属工艺

项目作者： 徐雪青

作者单位： 中国科学院广州能源研究所

项目金额： 12万元

中文摘要： 本项目采用连续离子层吸附反应法（SILAR）在多孔纳米TiO2电极上依次沉积InxS和CuyS，在S气氛550度条件下真空退火得到CuInS2量子点。材料微结构表征及器件光电化学测试结果表明，随着In-S敏化次数的增加，CuInS2量子点的结晶性能得到改善、内部缺陷减少，并在TiO2/CuInS2界面形成了In2S3缓冲层，使TiO2/CuInS2/多硫电解质界面化学电容、电子复合电阻增大，电子寿命显著提高，界面电子复合大大减少；太阳电池开路电压Voc升高、短路电流Jsc增大 (Voc最高达到0.4V, Jsc最高达到11.2mA/cm2))；此外，采用ZnS处理TiO2/CuInS2电极表面，可降低电子复合、提高电子注入效率，使太阳电池性能得到改善；但是当多孔TiO2电极孔道被过度填充，会造成纳米CuInS2敏化电极/电解质界面的比表面积下降，太阳电池填充因子劣化。总之，项目通过对材料内部与表面缺陷的控制、及界面电子复合过程的深入考察，结合理论分析揭示了量子点敏化太阳电池（QDSSCs）界面电子复合的主要途径与机制，为进一步降低电子复合、提高太阳电池效率提供了理论与实验依据。

中文关键词： CuInS2；量子点；电解质；敏化太阳能电池；界面电子复合

英文摘要： CuInS2 has been deposited onto the mesoporous TiO2 films by in sequence growth of InxS and CuyS via successive ionic layer absorption and reaction process (SILAR) and post-annealing in sulfur ambiance. It is found that with the increase of the deposition cycle of In-S, the crystalline quality of the CuInS2 improved and the defects of the materials decreased. Besides, an ultra thin layer of In2S3 has formed at TiO2/CuInS2 interface, which resulted in the increase of the chemical capacitance and electron recombination resistance, and the decrease of the electron recombination at TiO2/CuInS2 interfaces；As the results, the Voc and Jsc of the solar cells increased(Maximum of Voc=0.4V, Jsc=11.2mA/cm2)). On the other hand, with the increase of deposition cycles of In-S, the fill factor decreased due to the over filling of the pores of the mesoporous TiO2 films, which reduced the specific surface area of electrode/electrolyte interfaces. Combining impedance measurements and theoretic analysis, surface states and electron recombination process of QDSSCs has been systimatically investigated through innovative design of surface modification layers. The accomplishment of this project has revealed the interface electron recombination mechanism, and find an effective path to inhibit the electron recombination for QDSSCs, which has important theoretical and practical significance for the improvement of quantum efficiency of QDSSCs.

英文关键词： CuInS2;quantum dots;polyiodine;sensitized solar cells;interface electron recombination