Effects of Solvent Vapor Atmosphere on Photovoltaic Performance of Perovskite Solar Cells

Tremendous efforts have been devoted to facilitating the commercialization of perovskite solar cells (PSCs) in the past decade. However, the influence of solvent vapor atmosphere on PSC device performance during its fabrication still lacks related investigations. Here, by using three commonly employed solvent vapors during the perovskite annealing process, i.e., isopropanol, chlorobenzene and dimethylformamide, we reveal the effects of atmosphere on related perovskite film properties and device performance. The results indicate that perovskite films prepared under these external solvent vapors exhibit distinct crystalline phases, morphologies and optical properties from films under normal conditions (nitrogen gas), resulting in a significant drop in power conversion efficiency from the initial 20.01% to the lowest of only ~15%. Our work highlights the importance of atmospheric effects in preparing efficient PSCs for scalable fabrication and commercialization.