Li Fangjie, Hou Xiaoyi, Wang Zhen, Cui Xiaxia, Xie Guohua, Yan Feng, Zhao Xing-Zhong, Tai Qidong
The Insititute of Technological Sciences, Wuhan University, Wuhan 430072, P. R. China.
School of Physics and Technology, Wuhan University, Wuhan 430072, P. R. China.
ACS Appl Mater Interfaces. 2021 Sep 1;13(34):40656-40663. doi: 10.1021/acsami.1c11751. Epub 2021 Aug 18.
Nontoxic tin-based perovskite solar cells (Sn-PSCs) as a promising alternative to toxic Pb-PSCs have drawn great attention in recent years for their environmental friendliness and unique optoelectronic properties. However, both the efficiency and long-term stability of Sn-PSCs are considerably inferior to those of Pb-based ones. One of the main reasons is the difficulty in obtaining high-quality Sn-perovskite films due to the rapid crystallization of Sn-perovskites, which also results in poor device reproducibility. Here, we report a novel cation exchange strategy to prepare high-quality formamidinium tin triiodide (FASnI) perovskite films with a better controlled crystallization process and improved reproducibility, which allows easy access to smooth and pinhole-free perovskite films with oriented crystal growth, enlarged grain size, and reduced trap-state density. The corresponding Sn-PSCs show excellent photovoltaic performance with a champion efficiency of 9.11%, comparable to the best results reported for FASnI-PSCs, and the devices also demonstrate outstanding long-term stability without encapsulation. Our results offer a practical strategy for fabricating Sn-PSCs with superb performance and stability.
无毒的锡基钙钛矿太阳能电池（Sn-PSC）作为有毒的铅基钙钛矿太阳能电池（Pb-PSC）的一种有前景的替代品，近年来因其环境友好性和独特的光电特性而备受关注。然而，Sn-PSC的效率和长期稳定性都远低于铅基电池。主要原因之一是由于Sn-钙钛矿的快速结晶，难以获得高质量的Sn-钙钛矿薄膜，这也导致器件的重现性较差。在此，我们报告了一种新颖的阳离子交换策略，用于制备高质量的甲脒三碘化锡（FASnI）钙钛矿薄膜，其结晶过程得到更好的控制，重现性得到提高，从而能够轻松获得具有取向晶体生长、晶粒尺寸增大和陷阱态密度降低的光滑且无针孔的钙钛矿薄膜。相应的Sn-PSC表现出优异的光伏性能，冠军效率为9.11%，与报道的FASnI-PSC的最佳结果相当，并且这些器件在未封装的情况下也表现出出色的长期稳定性。我们的结果为制造具有卓越性能和稳定性的Sn-PSC提供了一种实用策略。
