钙钛矿太阳电池（PSCs）是薄膜太阳电池的最新发展和研究热点之一，其光电转换效率已达22.1%。CH3NH3PbI3（MAPbI3）薄膜中适量PbI2的存在已被证明可以提高PSCs的光电转换效率，但是其作用机理尚未完全明晰，PbI2存在的量和位置亦无法做到精确控制。.本项目在两步溶液法制备MAPbI3薄膜的过程中引入脉冲激光沉积技术（PLD）实现MAPbI3薄膜中PbI2钝化层位置和厚度等参数的精确控制；利用超快光谱、光电压/光电流瞬态响应、紫外光电子能谱、交流阻抗谱等测试手段结合第一性原理计算，研究PbI2钝化层对MAPbI3薄膜和PSCs中载流子的提取、传输和复合行为的影响规律，完善PbI2钝化作用的机制和机理；并研究PbI2钝化作用对PSCs性能的影响规律，以提高PSCs的性能。本项目的研究将为利用PbI2钝化作用提高PSCs性能提供技术基础和科学依据。

Perovskite solar cells (PSCs) are the latest development and one of the research focuses of thin film solar cells, and their record power conversion efficiency has reached 22.1%. It has been proved that appropriate amount of PbI2 existing in CH3NH3PbI3 (MAPbI3) films could improve the power conversion efficiency of PSCs, however, the corresponding mechanism is not yet completely clear, and the amount and location of PbI2 couldn’t be precisely controlled..Herein, we introduce pulsed laser deposition technique into the preparation of MAPbI3 films by two-step solution method to achieve the precise control of the parameters of PbI2 passivation layer in MAPbI3 films. The influence of PbI2 passivation layer on carrier extraction, transport, and recombination will be investigated through ultrafast spectroscopy, transient photovoltage/photocurrent, ultraviolet photoelectron spectroscopy, and electrochemical impedance spectroscopy measurements combined with first-principle calculations, and then the mechanism of PbI2 passivation effect will be improved and perfected. Furthermore, the influence of PbI2 passivation effect on the performance of PSCs will also be studied for improving the performance of PSCs. This study will provide technical and scientific basis for improving the performance of PSCs by utilizing PbI2 passivation effect.