Organic-inorganic hybrid perovskite solar cells (PSCs) have aroused tremendous research interest for their high efficiency, low cost and solution processability. However, the involvement of toxic lead in state-of-art perovskites hinders their market prospects. As an alternative, Sn-based perovskites exhibit similar semiconductor characteristics and can potentially achieve comparable photovoltaic performance in comparison with their lead-based counterparts. The main challenge of developing Sn-based PCSs lies in the intrinsic poor stability of Sn2+ , which could be oxidized and converted to Sn4+ . Notably, introduction of SnX2 (X=Cl, Br, I) additive becomes indispensable in the fabrication process, which highlights the importance of incorporating a reducing agent to improve the device stability. Additionally, efforts are made to utilize other reducing agents with different functions for the further enhancement of device performance. Currently, Sn-based PSCs could attain a record efficiency over 10% with great stability. In this review, we present the recent progress on reducing agents for improving the stability of Sn-based PSCs, and we hope to shed light on the challenges and opportunities of this research field.

中文翻译：

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用于提高Sn基钙钛矿太阳能电池稳定性的还原剂。

有机-无机混合钙钛矿太阳能电池（PSC）的高效率，低成本和溶液可加工性引起了人们极大的研究兴趣。但是，最先进的钙钛矿中有毒铅的介入阻碍了它们的市场前景。作为替代方案，锡基钙钛矿具有相似的半导体特性，与铅基钙钛矿相比，具有潜在的可比光伏性能。开发基于Sn的PCS的主要挑战在于Sn2 +固有的较差的稳定性，该稳定性可能被氧化并转化为Sn4 +。值得注意的是，在制造过程中引入SnX2（X = Cl，Br，I）添加剂变得必不可少，这突出了掺入还原剂以提高器件稳定性的重要性。另外，努力利用具有不同功能的其他还原剂来进一步增强装置性能。目前，基于锡的PSC可以达到创纪录的10％以上的效率，并且具有很高的稳定性。在这篇综述中，我们介绍了还原剂在改善锡基PSC稳定性方面的最新进展，我们希望阐明该研究领域的挑战和机遇。