热电/光电芯-壳结构一维纳米光阳极及其电荷输运机制研究

Dye-sensitized solar cells have significantly lower short-circuit current density than crystalline silicon solar cells , resulting in lower conversion efficiency. To solve this problem, this project intends to develop thermoelectric / photovoltaic core - shell one -dimensional composite materials as photoanodes of DSSC. Inner cores and outer shells of he photoanodes can cooperate and fulfil their own duties. On one hand, the shells achieve a good match with dyes, and on the other hand, thermoelectric cores with high conductivity play a role of fast conduction channel of electrons, which decreases electron-hole recombination probability and increases short-circuit current density. As a result, conversion efficiency of solar cells are improved substantially. In addition, thermoelectric potential of thermoelectric cores, which is derived from temperature difference between shady sides and irradiant sides of the solar cells according toseebeck effect, stacking with photovoltaic effect of DSSC, would also have an important affect on photoelectric properties of the solar cells. In the project, thermoelectric / photovoltaic core - shell one-dimensional nano photoanodes would be assembled into DSSC, to study systematicly charge transfer mechanism, especially the influence of thermoelectric cores on charge transfer. The charge transfer characteristics of the photoanode with the new structure would be revealed. Interaction between thermoelectric effect of the cores and photovoltaic effect of DSSC would be investigated thoroughly. Finally, DSSCs with increased short-circuit photocurrent density and high efficiency can be obtained. This project not only is significant for developing novel photoanode of the DSSC and contributing to the industrilization of the DSSC, but also provide a new idea for integrated utilization of different new energy technologies including photovoltaic devices and thermoelectric devices.

针对目前染料敏化太阳能电池存在转换效率效率偏低的问题，本项目拟开发热电/光电芯-壳结构一维纳米复合材料制备光阳极，使光阳极内芯与外壳各司其职，实现既能与染料能级良好匹配，又能使高导电率的热电材料芯成为电子传导的快速通道，减小电子空穴复合几率；同时在塞贝克效应与光电效应的叠加作用下，使短路电流密度大幅提高，进而提升电池的光电转换效率。通过将热电/光电芯-壳结构一维纳米光阳极组装成电池，系统研究电池的电荷输运机制，特别是热电材料内芯的存在对电池光生电荷输运的影响，揭示这种新型结构对电荷输运特性的影响规律和机制，以及热电材料内芯温差电动势与光阳极光生伏特效应的叠加机理及互相影响机制，并在此基础上，制备出高效率的太阳能电池器件。本项目为光电、热电等不同新能源技术的交叉融合发展与综合利用提供新思路，对于开发新型高性能光阳极并推动电池的产业化具有重要的现实意义。

本项目开发热电/光电芯-壳结构一维纳米复合材料制备光阳极，使光阳极内芯与外壳各司其职，实现既能与染料能级良好匹配，又能使高导电率的热电材料芯成为电子传导的快速通道，减小电子空穴复合几率；同时在热电材料内芯的塞贝克效应与光电效应的叠加作用下，使短路电流密度大幅提高，进而提升电池转换效率。通过将热电/光电芯-壳结构一维纳米光阳极组装成电池，系统研究电池电荷输运机制，特别是热电材料内芯对电池电荷输运的影响；揭示这种新型结构中的电荷输运特性与机制，以及热电材料内芯温差电动势与光阳极光伏效应的叠加机理及互相影响规律；并在此基础上，获得高效率太阳能电池器件。本项目按照预定计划顺利开展，并顺利完成预定研究目标。