Tin-based perovskite solar cells have exhibited great potential for their small bandgap, high carrier mobility, and non-toxic property. With an ever-increasing interest in putting on these lead-free perovskites, the oxidation of Sn(Ⅱ) to Sn(Ⅳ) has been revealed as one of the most crucial issues on their photovoltaic performance. Herein, the sources and impact of Sn(Ⅱ) oxidation and the correlated defects have been reviewed along with the suppression approaches. Compared to these defects in lead-based perovskites, the Sn vacancy dominants tin-based perovskite lattice due to their low formation energy. The essentially easy Sn(Ⅱ) oxidation can be attributed to the intrinsically low standard redox potential of Sn(Ⅱ)/Sn(Ⅳ) couple (0.15 V vs. SHE). Consequently, tin oxidation and its corresponding defective behavior seriously affect the device photovoltaic performance including output photovoltage and power conversion efficiency. We summarize these methods to suppress tin oxidation, such as tin halide compensation, reducing agents, composition and morphology optimization, and encapsulation. We further propose the prospective possible explorations for further restraining the tin oxidation process to improve the performances of tin-based perovskite solar cells.

锡基钙钛矿太阳能电池具有带隙小、载流子迁移率高和无毒等优点，显示出巨大的潜力。随着人们对这些无铅钙钛矿的兴趣日益浓厚，Sn(Ⅱ) 氧化为 Sn(Ⅳ) 已被揭示为影响其光伏性能的最关键问题之一。在此，综述了 Sn(Ⅱ) 氧化的来源和影响以及相关缺陷以及抑制方法。与铅基钙钛矿中的这些缺陷相比，锡基钙钛矿晶格的形成能较低，因此锡空位占主导地位。Sn(Ⅱ) 基本上容易氧化可归因于 Sn(Ⅱ)/Sn(Ⅳ) 对 (0.15 V vs. SHE) 固有的低标准氧化还原电位。最后，锡氧化及其相应的缺陷行为严重影响了器件的光伏性能，包括输出光电压和功率转换效率。我们总结了这些抑制锡氧化的方法，例如卤化锡补偿、还原剂、成分和形态优化以及封装。我们进一步提出了进一步抑制锡氧化过程以提高锡基钙钛矿太阳能电池性能的前瞻性探索。