Composite Encapsulation Enabled Superior Comprehensive Stability of Perovskite Solar Cells

and organic vapor at high temperature or upon light illumination, and the decomposition was reversible in a well-encapsulated environment, resulting in reversible performance degradation and recovery. The enhanced thermal stability was ascribed to the competition between the perovskite decomposition and reverse synthesis. The as-prepared high-quality, multilayered encapsulation scheme demonstrated superior sealing property, and no obvious performance decline was observed when the device was stored under ambient air, continuous light illumination, double 85 condition (85 °C, 85% humidity), or even water immersion. Therefore, this work paves the way for a scalable and robust encapsulation strategy feasible to hybrid perovskite optoelectronics in a reproducible manner.