Tailoring Defects Regulation in Air-Fabricated CsPbI3 for Efficient Inverted All-Inorganic Perovskite Solar Cells with Voc of 1.225 V

Sheng Fu; Nannan Sun; Jiabo Le; Wenxiao Zhang; Renjie Miao; Wenjun Zhang; Yongbo Kuang; Weijie Song; Junfeng Fang

doi:10.1021/acsami.2c07420

Tailoring Defects Regulation in Air-Fabricated CsPbI₃ for Efficient Inverted All-Inorganic Perovskite Solar Cells with V_oc of 1.225 V

ACS Appl Mater Interfaces. 2022 Jul 13;14(27):30937-30945. doi: 10.1021/acsami.2c07420. Epub 2022 Jun 29.

Authors

Sheng Fu^{1

2

3}, Nannan Sun^{1

3}, Jiabo Le¹, Wenxiao Zhang², Renjie Miao^{1

3}, Wenjun Zhang¹, Yongbo Kuang¹, Weijie Song¹, Junfeng Fang^{1

2

3}

Affiliations

¹ Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201, China.
² School of Physics and Electronics Science, Engineering Research Center of Nanophotonics & Advanced Instrument, Ministry of Education, East China Normal University, Shanghai 200241, China.
³ Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of Sciences, Beijing 100049, China.

PMID: 35767458
DOI: 10.1021/acsami.2c07420

Abstract

Air fabrication of CsPbI₃ perovskite photovoltaics has been attractive and fast-moving owing to its compatibility to low-cost and up-scalable fabrication. However, due to the inevitable erosions, undesirable traps are formed in air-fabricated CsPbI₃ crystals and seriously hinder photovoltaic performance with poor reproduction. Here, 3, 5-difluorobenzoic acid hydrazide (FBJ) is incorporated as trap regulation against external erosions in air-fabricated CsPbI₃. Theoretical simulations reveal that FBJ molecules feature stronger absorbance on CsPbI₃ than water, which can regulate trap formations for water erosions. In addition, FBJ with solid bonding interaction to CsPbI₃ can enlarge formation energy of various defects during crystallization and further suppress traps. Moreover, profiling to reductive hydrazine groups, FBJ inhibits traps for oxidation erosions. Consequently, a champion efficiency of 19.27% with an impressive V_oc of 1.225 V is realized with the inverted CsPbI₃ devices. Moreover, the optimized devices present superior stability and contain 97.4% after operating at 60 °C for 600 h.

Keywords: CsPbI3; Voc losses; air fabrication; inverted inorganic perovskite photovoltaics; stability; trap regulation.