The stability issues of perovskite solar cells (PSCs), especially illumination stability, have become a bottleneck that limits their further development, which needs urgent attention. Herein, we present a novel strategy for enhancing the illumination stability of PSCs using the radical scavenger of 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) to interrupt photoinduced radical decomposition. It is demonstrated that selectively generated triiodide with the addition of TEMPO can obliterate I-deficient phases during crystallization and passivate defects. More importantly, the photochemical decomposition of targeted perovskite polycrystalline films has been observably inhibited by the free-radical elimination effect of TEMPO. By harnessing TEMPO's defect passivation and radical-scavenging effects, target perovskite devices achieve an outstanding power conversion efficiency of 25.03%, maintaining over 90% of their initial efficiency after continuous maximum power point tracking under ISOS-L-2 conditions at 65 °C for 1000 hours. We demonstrate a novel perspective on the management of photochemical behavior in perovskite devices.

中文翻译：

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一种增强钙钛矿太阳能电池光稳定性的新型自由基反应中断策略

钙钛矿太阳能电池（PSC）的稳定性问题，特别是光照稳定性，已成为限制其进一步发展的瓶颈，亟待关注。在此，我们提出了一种利用 2,2,6,6-四甲基哌啶-1-氧基 (TEMPO) 自由基清除剂来中断光诱导自由基分解来增强 PSC 光照稳定性的新策略。结果表明，添加 TEMPO 选择性生成的三碘化物可以消除结晶过程中的 I 缺陷相并钝化缺陷。更重要的是，TEMPO的自由基消除作用明显抑制了目标钙钛矿多晶薄膜的光化学分解。通过利用 TEMPO 的缺陷钝化和自由基清除效应，目标钙钛矿器件实现了 25.03% 的出色功率转换效率，在 65 °C ISOS-L-2 条件下连续最大功率点跟踪后，仍保持其初始效率的 90% 以上。 1000小时。我们展示了钙钛矿器件中光化学行为管理的新视角。