Implementation of inorganic perovskite compounds and reduction toxicity of lead are important for developing sustainable and renewable photovoltaic power generation. The inorganic Pb/Sn binary metal halide perovskites offer a perfect opportunity for tuning optical bandgap and thus hold significant potential in emerging technologies such as solar cells. However, an easy oxidation of Sn²⁺ to Sn⁴⁺ has become one of the main issues for achieving efficient and stable Sn‐based perovskite solar cells (PSCs). Herein, an effective method for stabilizing CsPb_0.5Sn_0.5I₂Br is proposed to realize high‐efficiency PSCs via antioxidant tea polyphenol (TP). It is found that TP can not only slow down the oxidation of Sn²⁺ but also regulate perovskite film crystallization during the formation of perovskite films via coordination interaction, leading to a reduced density of defects and an enlarged open‐circuit voltage. The resultant perovskite solar cell using CsPb_0.5Sn_0.5I₂Br (TP) with an all‐inorganic mesoscopic framework of FTO/c‐TiO₂/m‐TiO₂/Al₂O₃/NiO/carbon achieves an impressive power conversion efficiency of 8.10% with high stability.

中文翻译：

---

抗氧化剂茶多酚稳定无机CsPb0.5Sn0.5I2Br钙钛矿化合物

无机钙钛矿化合物的实现和铅的还原毒性对于发展可持续和可再生的光伏发电非常重要。无机Pb / Sn二元金属卤化物钙钛矿为调整光学带隙提供了绝佳的机会，因此在新兴技术（例如太阳能电池）中具有巨大的潜力。但是，将Sn ²⁺容易氧化为Sn ⁴⁺已成为实现高效，稳定的Sn基钙钛矿太阳能电池（PSC）的主要问题之一。本文提出了一种稳定CsPb _0.5 Sn _0.5 I ₂ Br的有效方法，以通过抗氧化剂茶多酚（TP）实现高效的PSC。发现TP不仅可以减缓Sn的氧化²⁺还能通过配位相互作用调节钙钛矿膜的形成过程中钙钛矿膜的结晶，从而导致缺陷密度降低和开路电压增大。所得的钙钛矿太阳能电池使用CsPb _0.5 Sn _0.5 I ₂ Br（TP）和FTO / c-TiO ₂ / m-TiO ₂ / Al ₂ O ₃ / NiO / Carbon的全无机介观框架，实现了令人印象深刻的功率转换效率高稳定性的8.10％。