Tseng, Kai-WeiKai-WeiTsengChen, Guan-LinGuan-LinChenChen, Po-YuanPo-YuanChenHsieh, Hsiao-ChiHsiao-ChiHsiehLEE-YIH WANG2025-07-072025-07-072025-08https://www.scopus.com/record/display.uri?eid=2-s2.0-105007450079&origin=resultslisthttps://scholars.lib.ntu.edu.tw/handle/123456789/730608Defect passivation plays a pivotal role in perovskite solar cells (PSCs), effectively mitigating non-radiative recombination and significantly enhancing their photovoltaic performance and stability. Herein, the zwitterionic molecule cocamidopropyl betaine (CAPB) was introduced into 3D triple-cation lead mixed-halide (CsFAMA) perovskite films, enabling dual bulk and surface passivation. The quaternary ammonium group in CAPB established electrostatic interactions with iodine ions in PbI2, while its carboxylate and amide C=O groups coordinated with Pb2+ ions, effectively suppressing non-radiative recombination. Devices incorporating CAPB achieved a notable maximum power conversion efficiency (PCE) of 21.47 % and demonstrated exceptional humidity resistance, retaining 98 % of their initial PCE after 4,080 h under 25 °C and 50 % relative humidity. Additionally, hydrogen bonds formed between the carboxylate C=O, amide C=O, and N-H groups in CAPB and the N-H groups of amines effectively mitigated amine volatilization at elevated temperatures. As a result, CAPB-based devices maintained 93 % and 80 % of their original PCE after 1,872 h at 65 °C and 85 °C, respectively. The successful integration of CAPB for dual bulk and surface passivation underscores its significant potential in advancing photovoltaic technologies.CoordinationDefect passivationHydrogen bondZwitterionic molecule[SDGs]SDG7journal article10.1016/j.mtener.2025.101933