Metal halide perovskite solar cells (PSCs) have been considered as one of the most promising candidates for clean and renewable energy sources, but the existence of the detrimental defects at the surface and grain boundaries seriously deteriorates the power conversion efficiency (PCE) and stability of PSCs. Defect passivation has been verified to efficiently enhance the PCE and stability of PSCs. Herein, a kind of 4-biphenylcarboxylic acid (4-BBC) is first utilized to passivate the perovskite film by a post-treatment strategy, finally improving the performance of PSCs. The carbonyl group of 4-BBC as Lewis base can interact with the uncoordinated Pb²⁺ ions to heal the I^- vacancy defects, and its hydroxyl group can form hydrogen bond with I^- anion of the perovskite to suppress the I^- ionic migration. The hydrophobic biphenyl group of 4-BBC can also be beneficial to improve the stability of the perovskite film. As a result, the inverted PSCs with 4-BBC passivation indicate a best PCE (20.32 %) with lower hysteresis index (HI) of 0.39 % and better stability in comparison with the control PSCs (PCE = 18.71 %). The synergistic passivation of 4-BBC developed in this work offers an effective strategy for the fabrication of highly efficient and stable PSCs.

金属卤化物钙钛矿太阳能电池（PSC）被认为是清洁和可再生能源最有前途的候选者之一，但表面和晶界存在有害缺陷严重降低了功率转换效率（PCE）和稳定性PSC。缺陷钝化已被证实可有效提高 PSC 的 PCE 和稳定性。在此，首先利用一种4-联苯羧酸（4-BBC）通过后处理策略钝化钙钛矿薄膜，最终提高PSCs的性能。4-BBC的羰基作为路易斯碱可与未配位的Pb ²⁺离子相互作用修复I ^-空位缺陷，其羟基可与I ^{-形成氢键}钙钛矿的阴离子抑制 I ^-离子迁移。4-BBC的疏水性联苯基也有利于提高钙钛矿薄膜的稳定性。因此，与对照 PSC (PCE = 18.71%) 相比，具有 4-BBC 钝化的倒置 PSC 具有最佳 PCE (20.32%)，滞后指数 (HI) 较低，为 0.39%，稳定性更好。在这项工作中开发的 4-BBC 的协同钝化为制造高效稳定的 PSC 提供了一种有效的策略。