All-inorganic perovskite CsPbI₃ is an attractive light-absorbing layer material owing to its excellent light-absorbing ability and suitable band gap. However, as the research of perovskite progresses, the negative effects of the defect are further revealed. The uncoordinated Pb²⁺ and I⁻ vacancies within the perovskite film could inevitably lead to irreversible decay in the power conversion efficiency (PCE) as well as environmental instability for perovskite solar cells (PSCs), impeding the their commercialization process and further improvement in photovoltaic performance. Therefore, the new additive 4-Fluoro-3-phenoxybenzaldehyde (PB) containing fluorine and carboxyl groups is introduced as a dual functional passivator within the perovskite film. Under the cooperative passivation by carboxyl groups and fluorine, the optimized CsPbI₃ film exhibits denser morphology, lower density of defect states, as well as enhanced carrier transport properties. Ultimately, a high-performance PSC efficiency of 18.01% with enhanced stability is achieved. The optimized CsPbI₃ PSC still maintains 80% of original PCE after 1000 h of illumination with no encapsulation. The key to improving device performance is to fabricate the perovskite film with good morphology, large grain size, and low defect by utilizing the dual passivator of PB_.

全无机钙钛矿CsPbI ₃具有优异的吸光能力和合适的带隙，是一种极具吸引力的吸光层材料。然而，随着钙钛矿研究的深入，该缺陷的负面影响被进一步揭示。未配位的 Pb ²⁺和 I ^-钙钛矿薄膜内的空位不可避免地会导致功率转换效率 (PCE) 的不可逆衰减以及钙钛矿太阳能电池 (PSC) 的环境不稳定性，从而阻碍其商业化进程和光伏性能的进一步提高。因此，在钙钛矿薄膜中引入含有氟和羧基的新型添加剂 4-Fluoro-3-phenoxybenzaldehyde (PB) 作为双功能钝化剂。在羧基和氟的协同钝化下，优化后的CsPbI ₃薄膜具有更致密的形貌、更低的缺陷态密度以及增强的载流子传输性能。最终，实现了 18.01% 的高性能 PSC 效率和更高的稳定性。优化的 CsPbI ₃在没有封装的情况下光照 1000 小时后，PSC 仍保持原始 PCE 的 80%。提高器件性能的关键是利用PB双钝化剂制备形貌好、晶粒大、缺陷少的钙钛矿薄膜_。