Defects at the surface and grain boundaries at the interface between perovskite and electron transport layer (ETL) induce severe non-radiative recombination, detrimental to device's performance and stability. Organic materials are often used for surface passivation, but most works ascribed the great passivation ability to the formed two-dimensional (2D) perovskite. Here, we demonstrated that the organic halide salt hexaneammonium iodide (HAI) targets growth at grain boundaries and plays a critical role in suppressing the charge recombination instead of forming quasi-2D or 2D perovskite to passivate the surface defects. Moreover, the HAI invested the perovskite films with superhydrophobicity, enhancing the moisture resistance and preventing the diffusion of Li⁺ into perovskite films. As a result, boosting the efficiency of PSCs from 22.38% to 24.07% (certified efficiency of 23.59%) with a voltage deficit of 0.35 V. The surface treatment also enhances the operational stability of perovskite solar cells (PSCs), unencapsulated devices maintain 81.4% of their initial efficiency for 200 h under continuous light irradiation in the N₂ atmosphere.

钙钛矿和电子传输层 (ETL) 之间界面处的表面和晶界缺陷会导致严重的非辐射复合，不利于器件的性能和稳定性。有机材料通常用于表面钝化，但大多数工作将强大的钝化能力归因于形成的二维（2D）钙钛矿。在这里，我们证明了有机卤化物盐六碘化铵 (HAI) 以晶界处的生长为目标，并在抑制电荷复合而不是形成准二维或二维钙钛矿以钝化表面缺陷方面发挥关键作用。此外，HAI 还投资了具有超疏水性的​​钙钛矿薄膜，增强了防潮性并阻止了 Li ⁺的扩散。成钙钛矿薄膜。因此，在电压不足 0.35 V 的情况下，PSC 的效率从 22.38% 提高到 24.07%（认证效率为 23.59%）。表面处理还增强了钙钛矿太阳能电池 (PSC) 的运行稳定性，未封装的器件保持 81.4在 N ₂气氛中连续光照下 200 小时的初始效率的百分比。