Ye Tao, Wang Ke, Hou Yuchen, Yang Dong, Smith Nicholas, Magill Brenden, Yoon Jungjin, Mudiyanselage Rathsara R H H, Khodaparast Giti A, Wang Kai, Priya Shashank
Department of Materials Science and Engineering, Pennsylvania State University, University Park, Pennsylvania 16802, United States.
Materials Research Institute, Pennsylvania State University, University Park, Pennsylvania 16802, United States.
J Am Chem Soc. 2021 Mar 24;143(11):4319-4328. doi: 10.1021/jacs.0c13069. Epub 2021 Mar 11.
Black orthorhombic (B-γ) CsSnI with reduced biotoxicity and environmental impact and excellent optoelectronic properties is being considered as a promising eco-friendly candidate for high-performing perovskite solar cells (PSCs). A major challenge in a large-scale implementation of CsSnI PSCs includes the rapid transformation of Sn to Sn (within a few minutes) under an ambient-air condition. Here, we demonstrate that ambient-air stable B-γ CsSnI PSCs can be fabricated by incorporating ,'-methylenebis(acrylamide) (MBAA) into the perovskite layer and by using poly(3-hexylthiophene) as the hole transporting material. The lone electron pairs of -NH and -CO units of MBAA are designed to form coordination bonding with Sn in the B-γ CsSnI, resulting in a reduced defect (Sn) density and better stability under multiple conditions for the perovskite light absorber. After a modification, the highest power conversion efficiency (PCE) of 7.50% is documented under an ambient-air condition for the unencapsulated CsSnI-MBAA PSC. Furthermore, the MBAA-modified devices sustain 60.2%, 76.5%, and 58.4% of their initial PCEs after 1440 h of storage in an inert condition, after 120 h of storage in an ambient-air condition, and after 120 h of 1 Sun continuous illumination, respectively.
具有降低的生物毒性和环境影响以及优异光电性能的黑色正交晶系（B-γ）CsSnI，正被视为高性能钙钛矿太阳能电池（PSC）的一种有前景的环保候选材料。大规模实施CsSnI PSC的一个主要挑战包括在环境空气条件下Sn在几分钟内迅速转变为Sn。在此，我们证明通过将N,N'-亚甲基双丙烯酰胺（MBAA）掺入钙钛矿层并使用聚（3-己基噻吩）作为空穴传输材料，可以制造出在环境空气中稳定的B-γ CsSnI PSC。MBAA的-NH和-CO单元的孤对电子旨在与B-γ CsSnI中的Sn形成配位键，从而降低缺陷（Sn）密度，并使钙钛矿光吸收体在多种条件下具有更好的稳定性。经过改性后，未封装的CsSnI-MBAA PSC在环境空气条件下记录到的最高功率转换效率（PCE）为7.50%。此外，MBAA改性的器件在惰性条件下储存1440小时后、在环境空气条件下储存120小时后以及在1个太阳连续光照120小时后，分别保持其初始PCE的60.2%、76.5%和58.4%。
