Tailoring Component Interaction for Air‐Processed Efficient and Stable All‐Inorganic Perovskite Photovoltaic

• Published in: Angewandte Chemie International Edition Vol. 59; no. 32; pp. 13354 - 13361
• Main Authors: Wang, Xiaojuan, Ran, Xueqin, Liu, Xiaotao, Gu, Hao, Zuo, Shouwei, Hui, Wei, Lu, Hui, Sun, Bo, Gao, Xingyu, Zhang, Jing, Xia, Yingdong, Chen, Yonghua, Huang, Wei
• Format: Journal Article
• Language: English
• Published: Germany Wiley Subscription Services, Inc 03.08.2020
• Edition: International ed. in English
• Subjects: Acetic acid; all-inorganic perovskite; chemical interactions; Crystallization; Dimethyl sulfoxide; Dimethylformamide; Hydrogen bonds; Ionic liquids; Lead; Lead compounds; Metal halides; Optoelectronics; perovskite solar cells; Perovskites; Photovoltaic cells; Photovoltaics; Precursors; solution processed in air; Solvents; Strong interactions (field theory); solution processed in air; chemical interactions; perovskite solar cells; all-inorganic perovskite
• ISSN: 1433-7851; 1521-3773; 1521-3773
• DOI: 10.1002/anie.202004256

All‐inorganic lead halide perovskites are promising candidates for optoelectronic applications. However, fundamental questions remain over the component interaction in the perovskite precursor solution due to the limitation of the most commonly used solvents of N,N‐dimethylformamide (DMF) and dimethyl sulfoxide (DMSO). Here, we report an interaction tailoring strategy for all‐inorganic CsPbI3−xBrx perovskites by involving the ionic liquid solvent methylammonium acetate (MAAc). C=O shows strong interaction with lead (Pb2+) and N−H⋅⋅⋅I hydrogen bond formation is observed. The interactions stabilize the perovskite precursor solution and allow production of the high‐quality perovskite films by retarding the crystallization. Without the necessity for antisolvent treatment, the one‐step air‐processing approach delivers photovoltaic cells regardless of humidity, with a high efficiency of 17.10 % along with long operation stability over 1500 h under continuous light illumination. By involving a methyl ammonium acetate (MAAc) ionic liquid solvent, strong Pb−O interaction and N−H⋅⋅⋅I hydrogen bonds between MAAc and PbI2 lead to a controllable all‐inorganic perovskite formation in ambient air. The resulting solar cells exhibit high efficiency and excellent stability under continuous light illumination.