Many organic molecules with various functional groups have been used to passivate the perovskite surface for improving the efficiency and stability of perovskite solar cell (PSCs). However, the intrinsic attributes of the passivation effect based on different chemical bonds are rarely studied. Here, we comparatively investigate the passivation effect among 12 types of functional groups on para-tert-butylbenzene for PSCs and find that the open circuit voltage (V_OC) tends to increase with the chemical bonding strength between perovskite and these passivation additive molecules. Particularly, the para-tert-butylbenzoic acid (tB-COOH), with the extra intermolecular hydrogen bonding, can stabilize the surface passivation of perovskite films exceptionally well through formation of a crystalline interlayer with water-insoluble property and high melting point. As a result, the tB-COOH device achieves a champion power conversion efficiency (PCE) of 21.46%. More importantly, such devices, which were stored in ambient air with a relative humidity of ≃45%, can retain 88% of their initial performance after a testing period of more than 1 year (10,080 h). This work provides a case study to understand chemical bonding effects on passivation of perovskite.

许多具有各种官能团的有机分子已被用于钝化钙钛矿表面，以提高钙钛矿太阳能电池（PSC）的效率和稳定性。然而，很少研究基于不同化学键的钝化效应的内在属性。在这里，我们比较研究了 12 种官能团对PSC 的对叔丁基苯的钝化效果，发现开路电压 ( V _OC ) 倾向于随着钙钛矿与这些钝化添加剂分子之间的化学键合强度而增加。特别是，第- 叔丁基苯甲酸 (tB-COOH) 具有额外的分子间氢键，通过形成具有水不溶性和高熔点的结晶中间层，可以非常好地稳定钙钛矿薄膜的表面钝化。结果，tB-COOH 器件实现了 21.46% 的冠军功率转换效率 (PCE)。更重要的是，这些存储在相对湿度为 ≃45% 的环境空气中的设备在经过超过 1 年（10,080 小时）的测试后仍可保持其初始性能的 88%。这项工作提供了一个案例研究，以了解化学键合对钙钛矿钝化的影响。