There is growing evidence that the stability of perovskite solar cells (PSCs) is strongly dependent on the interface chemistry between the absorber films and adjacent charge‐transport layers, whereas the exact mechanistic pathways remain poorly understood. Herein, a straightforward approach is presented for decoupling the degradation effects induced by the top fullerene‐based electron transport layer (ETL) and various bottom hole‐transport layer (HTL) materials assembled in p‐i‐n PSCs. It is shown that chemical interaction of MAPbI₃ absorber with ETL comprised of the fullerene derivative most aggressively affects the device operational stability. However, washing away the degraded fullerene derivative and depositing fresh ETL leads to restoration of the initial photovoltaic performance when bottom perovskite/HTL interface is not degraded. Following this approach, it is possible to compare the photostability of stacks with various HTLs. It is shown that poly(3,4‐ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) and NiO_x induce significant degradation of the adjacent perovskite layer under light exposure, whereas poly[bis(4‐phenyl)(2,4,6‐trimethylphenyl)amine] (PTAA) provides the most stable perovskite/HTL interface. A time‐of‐flight secondary ion mass spectrometry (ToF‐SIMS) analysis allows identification of chemical origins of the interactions between MAPbI₃ and HTLs. The proposed research methodology and the revealed degradation pathways should facilitate the development of efficient and stable PSCs.

中文翻译：

---

电荷传输中间层对光致p-i-n钙钛矿太阳能电池降解的解耦贡献

越来越多的证据表明，钙钛矿太阳能电池（PSC）的稳定性在很大程度上取决于吸收膜与相邻电荷传输层之间的界面化学性质，而确切的机理途径仍知之甚少。本文提出了一种简单的方法来解耦由组装在p-i-n PSC中的顶层富勒烯电子传输层（ETL）和各种底部空穴传输层（HTL）材料引起的降解效应。结果表明，MAPbI _3的化学相互作用具有富勒烯衍生物的ETL的吸收剂最积极地影响器件的操作稳定性。但是，当底部钙钛矿/ HTL界面未降解时，洗去降解的富勒烯衍生物并沉积新鲜的ETL可以恢复初始光伏性能。按照这种方法，可以将堆栈与各种HTL的光稳定性进行比较。结果表明，聚（3,4-乙烯二氧噻吩）：聚苯乙烯磺酸盐（PEDOT：PSS）和NiO _x在光照下会引起相邻钙钛矿层的显着降解，而聚[双（4-苯基）（2,4,6-三甲基苯基）胺]（PTAA）提供了最稳定的钙钛矿/ HTL界面。飞行时间二次离子质谱（ToF-SIMS）分析可以识别MAPbI ₃与HTL之间相互作用的化学起源。拟议的研究方法和揭示的降解途径应有助于开发高效，稳定的PSC。