A crystal capping layer for formation of black-phase FAPbI3 perovskite in humid air

• 成果类型: Article
• 署名作者: Zou, Yu; Yu, Wenjin; Guo, Haoqing; Li, Qizhi; Li, Xiangdong; Li, Liang; Liu, Yueli; Wang, Hantao; Tang, Zhenyu; Yang, Shuang; Chen, Yanrun; Qu, Bo; Gao, Yunan; Chen, Zhijian; Wang, Shufeng; Zhang, Dongdong; Chen, Yihua; Chen, Qi; Zakeeruddin, Shaik M.; Peng, Yingying; Zhou, Huanping; Gong, Qihuang; Wei, Mingyang; Graetzel, Michael; Xiao, Lixin
• 署名单位: Peking University; Peking University; Peking University; Tsinghua University; Beijing Institute of Technology; Swiss Federal Institutes of Technology Domain; Ecole Polytechnique Federale de Lausanne; Huairou Laboratory
• 刊物名称: SCIENCE
• ISSN/ISSBN: 0036-11197
• DOI: 10.1126/science.adn9646
• 发表日期: 2024-07-12
• 页码: 161-167
• 关键词: solar-cells; EFFICIENCY; formamidinium; temperature; degradation; grain

摘要

Black-phase formamidinium lead iodide (alpha-FAPbI(3)) perovskites are the desired phase for photovoltaic applications, but water can trigger formation of photoinactive impurity phases such as delta-FAPbI(3). We show that the classic solvent system for perovskite fabrication exacerbates this reproducibility challenge. The conventional coordinative solvent dimethyl sulfoxide (DMSO) promoted delta-FAPbI(3) formation under high relative humidity (RH) conditions because of its hygroscopic nature. We introduced chlorine-containing organic molecules to form a capping layer that blocked moisture penetration while preserving DMSO-based complexes to regulate crystal growth. We report power conversion efficiencies of >24.5% for perovskite solar cells fabricated across an RH range of 20 to 60%, and 23.4% at 80% RH. The unencapsulated device retained 96% of its initial performance in air (with 40 to 60% RH) after 500-hour maximum power point operation.