Inverted perovskite solar cells (PSCs) have significant potential in large-scale production due to their low cost and low-temperature process-ability. Nevertheless, the efficiency of the inverted PSCs suffers from non-ideal light-harvesting, surface recombination, and charge extraction loss. Here, tetraoctylammonium bromide (TOAB) is introduced by a post-treatment strategy to address these challenges. The film properties and the corresponding device performance are systemically studied. The results show that TOAB molecules distribute throughout the perovskite films and thus effectively passivate the trap states at grain boundaries (GBs) and surface. The built-in electrical field (V_bi) of the devices and hydrophobic properties of the perovskite films are enhanced by TOAB molecular arrangement at the perovskite surface. Moreover, the light-harvesting efficiency is also improved via the redistribution of the light field in the PSCs. Benefiting from trap sates passivation, enhanced V_bi and light-harvesting, the champion power conversion efficiency (PCE) of 21.47% is achieved, which is among the reported high efficiencies for inverted PSCs. In addition, device stability has been greatly improved. The PCE of PSCs treated by TOAB can retain 81% of its initial value after 264 h in the air and can retain 94% of its initial value after 71 days in N₂. This work represents a novel passivation strategy by post-treatment method without disturbing the perovskite film growth to understand the sole defect effects on the device performance of PSCs.

倒钙钛矿太阳能电池（PSC）由于其低成本和低温加工能力而在大规模生产中具有巨大潜力。然而，反型PSC的效率受到非理想的光收集，表面重组和电荷提取损失的困扰。在这里，通过后处理策略引入了溴化四辛基溴化铵（TOAB）来应对这些挑战。系统地研究了膜的性质和相应的器件性能。结果表明，TOAB分子分布在整个钙钛矿薄膜中，从而有效地钝化了晶界（GBs）和表面的陷阱态。内置电场（V _bi装置的钙钛矿膜的疏水性通过钙钛矿表面的TOAB分子排列而得以增强。此外，通过在PSC中重新分配光场，还可以提高光收集效率。得益于陷阱状态的钝化，增强的V _bi和光捕获，实现了21.47％的冠军功率转换效率（PCE），这是报道的反向PSC的高效率之一。此外，设备的稳定性得到了极大的提高。经过TOAB处理的PSC的PCE在空气中264 h后可保留其初始值的81％，在N _2中71天后可保留其初始值的94％。。这项工作代表了一种通过后处理方法形成的新型钝化策略，而不会干扰钙钛矿膜的生长，从而了解对PSC器件性能的唯一缺陷影响。