本项目拟采用我们提出的水浴法和改进的浆料旋涂法低温大面积制备金红石相SnO2薄膜，研究其提升钙钛矿太阳电池电子传输层性能的微观机制。通过超临界流体处理与Cl离子表面处理等对衬底/SnO2薄膜/钙钛矿晶体之间的界面进行修饰与缺陷钝化，在它们之间构筑有利于电子快速转移与传输，且电荷复合得到最大程度抑制的异质结界面及与之相匹配的能级结构，降低电子传导损失。深入研究采用卤素(Cl、Br)掺杂、Cs（与/或Rb）A位掺杂、CH3NH3PbX3和HC(NH2)2PbX3混合，并与PCBM多元复合调控钙钛矿晶粒大小、晶界、能带、载流子迁移率及其扩散长度的机制，增强光吸收、加速载流子分离与传输。综合提升基于SnO2薄膜的柔性大面积平面异质结钙钛矿太阳电池的光电转换性能，显著减弱电流回滞，提高稳定性。为其实用化奠定一定的理论与实验基础。

This project intends to use the water bath method and the improved spin coating method to prepare rutile phase SnO2 thin film at low temperature and study the microscopic mechanism to improve the electron transport layer performance of the perovskite solar cells. The supercritical fluid treatment and Cl ion treatment are proposed to modify the interfaces between the substrate/SnO2/perovskite crystals and passivate the defects, respectively. A hetero junction between them with corresponding energy level structure is expected to be established to facilitate the rapid electron transfer and transmission, and suppress charge recombination to the most degree to reduce the electron conduction loss. Meanwhile, the modulation mechanism of grain size, grain boundary, band structure, carrier mobility and diffusion length by using the mixed cations (Cl, Br doping), Cs (and/or Rb) doped halides perovskite (CH3NH3PbX3 mixed with HC(NH2)2PbX3) composited with PCBM will be investigated systematically, to enhance light absorption and accelerate carrier separation and transmission. Through this study, the flexible large area planar heterojunction perovskite solar cells with the comprehensively promoted photoelectric conversion performance, the remarkably reduced current hysteresis, and the improved stability would be yielded.