钙钛矿电池中有机卤化铅/宽带半导体异质结界面电荷输运性质与调控

Perovskite organic lead halide solar cells have attracted much research interest due to their outstanding photoelectricity properties and low cost. Currrently, the main work is the promotion of the efficiency, including the optimization of film deposition and material design. However, few works have been focused on the interfacial charge transport, which makes it ambigious in understanding the working mechanism and charge properties in the cell. In this project,based on Anderson heterojunction diffusion model, a new theory for analyzing electrochemical impedance spectra of perovskite solar cells will be developed. And the dynamics on photogenerated electron seperation, collection and recombination processes will be revealed. Besides,a series of heterojunction interfaces will be established, which is based on wide bandgap semiconductor films with different morphologies and crystal orientations. Interfacial electron transportation properties will be investigated as well. Finally, interfacial modification will be carried out in order to restrain the interfacial recombination, improve the electron collection efficiency and cell performance.

钙钛矿薄膜太阳能电池因其优异的光电转换性能和低廉的制备成本吸引了众多科研工作者的注意。目前，此类电池研究主要集中在改善薄膜沉积质量和设计新材料方面，而有关电池中有机卤化铅钙钛矿/宽禁带半导体异质结界面研究非常少，对钙钛矿电池的界面电荷输运性质和界面结构等方面的认识不清晰、不深入。针对上述问题，本项目首先基于Anderson异质半导体模型，发展适用于钙钛矿电池阻抗研究的相关理论，为揭示界面电荷分离、收集和复合等物理机制提供理论指导；基于不同形貌和晶面取向的宽禁带半导体薄膜，构筑一系列异质半导体界面，运用电化学阻抗谱、时间分辨光致吸收、发射谱、表面光电压光谱等方法研究界面电荷输运性质；在此基础上，利用ALD沉积技术进行界面修饰和调控，抑制界面复合，提高电荷收集效率，进一步提高电池性能。

钙钛矿薄膜太阳能电池因其优异的光电转换性能和低廉的制备成本吸引了众多科研工作者的注意。目前，此类电池研究主要集中在改善薄膜沉积质量和设计新材料方面，而有关电池中有机卤化铅钙钛矿/宽禁带半导体异质结界面研究非常少，对钙钛矿电池的界面电荷输运性质和界面结构等方面的认识不清晰、不深入。针对上述问题，本项目首先基于Anderson 异质半导体模型，发展了适用于钙钛矿电池阻抗研究的相关理论，为揭示界面电荷分离、收集和复合等物理机制提供理论指导；基于自掺杂调控了宽禁带半导体和钙钛矿材料的电荷载流子浓度，构筑一系列异质半导体界面，运用电化学阻抗谱、电容-电压、发射谱、瞬态光电流/电压等方法研究界面电荷输运性质，并证明了钙钛矿电池是一种典型的异质结太阳能电池；在此基础上，利用ALD 、液相旋涂等薄膜沉积技术进行界面修饰和调控，抑制界面复合，提高电荷收集效率，进一步提高了电池性能。