Xiaoqiang Shi1,2, Ruochen Chen1,2, Tingting Jiang1,2, Shuang Ma1,2, Xuepeng Liu1,2, Yong Ding1,2, Molang Cai1,2, Jihuai Wu3, Songyuan Dai1,2
1Beijing Key Laboratory of Novel Thin-Film Solar Cells, North China Electric Power University, Beijing, 102206 P. R. China
2State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources, North China Electric Power University, Beijing 102206, P.R. China
3Fujian Provincial Key Laboratory of Photoelectric Functional Materials, Institute of Materials Physical Chemistry, Huaqiao University, Xiamen, 361021 P. R. China
Tóm tắt
Control of dynamics at the electron transport layer–perovskite interface, such as charge transfer and recombination, is essential in achieving high‐efficiency planar perovskite solar cells (PSCs). Herein, it was observed that the trade‐off between unfavorable electron transport of a thick SnO2 film and serious electron recombination at thin SnO2 film/perovskite interfaces is essential for the performance of SnO2‐based planar PSCs. The optimized efficiency of devices beyond 20% is obtained by using a two‐step deposition of SnO2. Moreover, trap‐assisted carrier recombination is significantly suppressed by using the diethylenetriaminepentaacetic acid passivator via the formation of coordination with undercoordinated Sn and Pb2+ ions. As a result, the champion device demonstrates a promising efficiency of 21.28% with negligible hysteresis and much improved environmental stability, i.e., retaining 98% of the initial efficiency under ambient atmosphere over 1000 h.
