Tai Qidong, Guo Xuyun, Tang Guanqi, You Peng, Ng Tsz-Wai, Shen Dong, Cao Jiupeng, Liu Chun-Ki, Wang Naixiang, Zhu Ye, Lee Chun-Sing, Yan Feng
Department of Applied Physics, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, P. R. China.
Center of Super-Diamond and Advanced Films (COSDAF), and Department of Chemistry, City University of Hong Kong, Hong Kong, P. R. China.
Angew Chem Int Ed Engl. 2019 Jan 14;58(3):806-810. doi: 10.1002/anie.201811539. Epub 2018 Dec 17.
Tin-based perovskites with excellent optoelectronic properties and suitable band gaps are promising candidates for the preparation of efficient lead-free perovskite solar cells (PSCs). However, it is challenging to prepare highly stable and efficient tin-based PSCs because Sn in perovskites can be easily oxidized to Sn upon air exposure. Here we report the fabrication of air-stable FASnI solar cells by introducing hydroxybenzene sulfonic acid or its salt as an antioxidant additive into the perovskite precursor solution along with excess SnCl . The interaction between the sulfonate group and the Sn ion enables the in situ encapsulation of the perovskite grains with a SnCl -additive complex layer, which results in greatly enhanced oxidation stability of the perovskite film. The corresponding PSCs are able to maintain 80 % of the efficiency over 500 h upon air exposure without encapsulation, which is over ten times longer than the best result reported previously. Our results suggest a possible strategy for the future design of efficient and stable tin-based PSCs.
具有优异光电性能和合适带隙的锡基钙钛矿是制备高效无铅钙钛矿太阳能电池（PSC）的有前途的候选材料。然而，制备高度稳定且高效的锡基PSC具有挑战性，因为钙钛矿中的Sn在暴露于空气中时很容易被氧化成Sn。在此，我们报告了通过将羟基苯磺酸或其盐作为抗氧化添加剂与过量的SnCl一起引入钙钛矿前驱体溶液中来制备空气稳定的FASnI太阳能电池。磺酸根基团与Sn离子之间的相互作用使得钙钛矿晶粒能够被SnCl添加剂复合层原位封装，这导致钙钛矿薄膜的氧化稳定性大大提高。相应的PSC在不封装的情况下暴露于空气中500小时后能够保持80%的效率，这比之前报道的最佳结果长十多倍。我们的结果为未来高效稳定的锡基PSC设计提供了一种可能的策略。
