A multifunctional C + epoxy/Ag-paint cathode enables efficient and stable operation of perovskite solar cells in watery environments

Abstract

Organic/inorganic hybrid perovskite solar cells (PSCs) have attracted wide attention mainly due to the rapid rise in their power conversion efficiency (PCE), but their long-term stability is now becoming an even more important issue given that the active perovskite material is moisture sensitive. Herein we report a hole-transporter-free PSC based on a C + epoxy electrode that can serve as both a hole-selective extractor and a water-rejecting barrier. After boosting with a silver paint coating, the whole device is not only efficient at ∼11% but also waterproof. When immersed in water, no performance degradation occurred at the first 80 min. More impressively, when the cell stability was investigated in some harsh environments, e.g., high humidity and 50 °C thermal stressing, nearly no performance degradation was observed within the testing time span.