Wide Bandgap Interface Layer Induced Stabilized Perovskite/Silicon Tandem Solar Cells with Stability over Ten Thousand Hours

Abstract The perovskite/silicon tandem solar cell (PK/c‐Si TSC) is a reasonable choice that can break through the efficiency limitations of silicon cells. Here, the p‐i‐n perovskite solar cell is conformally grown by the evaporation–solution combination technique on fully‐textured silicon heterojunction cells to realize two‐terminal PK/c‐Si TSCs. Due to the adverse effect of the residual PbI 2 at the bottom of the perovskite bulk on device performance, a thermal‐evaporated CsBr thin layer is introduced between the perovskite layer and the hole transport layer to construct a gradient perovskite absorber for optimized energy level alignment, so as to improve the open‐circuit voltage and fill factor of the device. Finally, the PK/c‐Si tandem cell achieves an efficiency of 27.48% and is stable in nitrogen over 10 000 h.