Hybrid vapor-solution processing and evaporated dual-interface engineering enable FAPbI₃-based solar cells with thermal stability beyond 10 000 hours

Abstract

The hybrid evaporation/solution-coating method holds great promise for perovskite manufacturing and textured tandem architectures. Nevertheless, it has predominantly been applied to wide-bandgap (>1.65 eV) perovskites, while FAPbI3-based compositions remain underexplored. Here, we establish a hybrid vapor–solution FAPbI3-based perovskite platform and identify key roles of precursor composition and annealing conditions in perovskite formation. Building on this platform, an evaporated dual-interface CsBr engineering strategy is demonstrated, combining precise interfacial modification with enhanced device performance and thermal stability. Ultrathin CsBr layers deposited by thermal evaporation at both the bottom and top interfaces effectively hinder defect formation during thermal aging. This approach yields p–i–n perovskite solar cells based on sputtered NiOx with power conversion efficiencies exceeding 23%. Most notably, devices retain over 88% of their initial efficiency after more than 10 400 h of thermal aging at 85 °C under ISOS-D-2I (dark, inert atmosphere) conditions.