Effective Surface Treatment for High-Performance Inverted CsPbI2Br Perovskite Solar Cells with Efficiency of 15.92%

Nano-Micro Letters

Sheng Fu¹  Junfeng Fang¹  Li Wan¹  Weijie Song¹  Wenxiao Zhang¹  Xiaodong Li² 

[1] Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences;School of Physics and Electronics Science, Engineering Research Center of Nanophotonics & Advanced Instrument, Ministry of Education, East China Normal University;

关键词: CsPbI2Br;    Inverted perovskite solar cells;    Effective passivation;    V oc loss;    Stability;   

DOI  :  10.1007/s40820-020-00509-y

来源: DOAJ

【 摘 要 】

Highlights A simple and multifunctional surface treatment strategy is proposed to address the inferior-performance inverted CsPbI2Br perovskite solar cells (PSCs). The induced-ions exchange can align energy levels, passivate both GBs and surface, and gift the solid protection from external erosions. The inverted CsPbI2Br PSCs reveal a champion efficiency of 15.92% and superior stability after moisture, operational, and thermal ages. Abstract Developing high-efficiency and stable inverted CsPbI2Br perovskite solar cells is vitally urgent for their unique advantages of removing adverse dopants and compatible process with tandem cells in comparison with the regular. However, relatively low opening circuit voltage (V oc ) and limited moisture stability have lagged their progress far from the regular. Here, we propose an effective surface treatment strategy with high-temperature FABr treatment to address these issues. The induced ions exchange can not only adjust energy level, but also gift effective passivation. Meanwhile, the gradient distribution of FA+ can accelerate the carriers transport to further suppress bulk recombination. Besides, the Br-rich surface and FA+ substitution can isolate moisture erosions. As a result, the optimized devices show champion efficiency of 15.92% with V oc of 1.223 V. In addition, the tolerance of humidity and operation get significant promotion: maintaining 91.7% efficiency after aged at RH 20% ambient condition for 1300 h and 81.8% via maximum power point tracking at 45 °C for 500 h in N2. Furthermore, the unpackaged devices realize the rare reported air operational stability and, respectively, remain almost efficiency (98.9%) after operated under RH 35% for 600 min and 91.2% under RH 50% for 300 min. Graphic Abstract

【 授权许可】

Unknown