High-efficiency and thermally stable FACsPbI3 perovskite photovoltaics

• 成果类型: Article
• 署名作者: Li, Saisai; Jiang, Yuanzhi; Xu, Jian; Wang, Di; Ding, Zijin; Zhu, Tong; Chen, Bin; Yang, Yingguo; Wei, Mingyang; Guo, Renjun; Hou, Yi; Chen, Yu; Sun, Changjiu; Wei, Keyu; Qaid, Saif M. H.; Lu, Haizhou; Tan, Hairen; Di, Dawei; Chen, Jun; Gratzel, Michael; Sargent, Edward H.; Yuan, Mingjian
• 署名单位: Nankai University; University of Toronto; Beijing Institute of Technology; Fudan University; Swiss Federal Institutes of Technology Domain; Ecole Polytechnique Federale de Lausanne; National University of Singapore; Chinese Academy of Sciences; Institute of High Energy Physics, CAS; King Saud University; Southeast University - China; Nanjing University; Zhejiang University; Nankai University; Haihe Laboratory of Sustainable Chemical Transformations
• 刊物名称: Nature
• ISSN/ISSBN: 0028-5016
• DOI: 10.1038/s41586-024-08103-7
• 发表日期: 2024-11-07
• 关键词: halide perovskites; solar; stabilization

摘要

alpha-FA1-xCsxPbI3 is a promising absorbent material for efficient and stable perovskite solar cells (PSCs)1,2. However, the most efficient alpha-FA1-xCsxPbI3 PSCs require the inclusion of the additive methylammonium chloride3,4, which generates volatile organic residues (methylammonium) that limit device stability at elevated temperatures5. Previously, the highest certified power-conversion efficiency of alpha-FA1-xCsxPbI3 PSCs without methylammonium chloride was only approximately 24% (refs. 6,7), and these PSCs have yet to exhibit any stability advantages. Here we identify interfacial contact loss caused by the accumulation of Cs+ in conventional alpha-FA1-xCsxPbI3 PSCs, which deteriorates device performance and stability. Through in situ grazing-incidence wide-angle X-ray scattering analysis and density functional theory calculations, we demonstrate an intermediate-phase-assisted crystallization pathway enabled by acetate surface coordination to fabricate high-quality alpha-FA1-xCsxPbI3 films, without using the methylammonium additive. We herein report a certified stabilized power output efficiency of 25.94% and a reverse-scanning power-conversion efficiency of 26.64% for alpha-FA1-xCsxPbI3 PSCs. Moreover, the devices exhibited negligible contact losses and enhanced operational stability. They retained over 95% of their initial power-conversion efficiency after operating for over 2,000 h at the maximum power point under 1 sun, 85 degrees C and 60% relative humidity (ISOS-L-3). Suppressing surface Cs+ accumulation in methylammonium-free alpha-FA1-xCsxPbI3 perovskite with an intermediate phase-assisted strategy enables high-efficiency and thermally stable photovoltaics.