埋 底 界 面 修 饰 实 现 高 效 稳 定 钙 钛 矿 太 阳 能 电 池

Interface engineering at the bottom can effectively enhance the efficiency and stability of perovskite solar cells. In this study, the surface modifier, bis(triphenylphosphine)cobalt chloride (BTPPCC), was employed as a pre-buried interface modifier, successfully passivating the surface-enriched defects of MAPbI₃ perovskite films. This optimization improved the interface contact between the perovskite film and the underlying hole transport layer (HTL), enhancing the crystalline performance of the perovskite absorption layer. Additionally, BTPPCC effectively suppressed non-radiative recombination at the interface, improving the long-term stability of the device. As a result, the power conversion efficiency (PCE) of the p-i-n type device increased from 18.37% to 20.12%. The unencapsu-lated device maintained an efficiency of over 76% after continuous operation for nearly 500 hours in an ambient air environment with a relative humidity (RH) of 50% at room temperature. This study provides an effective method for optimizing the buried interface in perovskite solar cells.