Two-/Three-Dimensional Perovskite Bilayer Thin Films Post-Treated with Solvent Vapor for High-Performance Perovskite Photovoltaics.

Perovskite photovoltaics (PPVs) using three-dimensional (3D) perovskites incorporated with two-dimensional (2D) perovskites have drawn great concentration in both academic and industrial sectors. Here, we report high performance of PPVs based on the 2D/3D perovskite bilayer thin film post-annealed with solvent vapor. The 2D/3D perovskite bilayer thin film post-annealed with solvent vapor possesses enlarged crystal size and crystallinity and blue-shifted photoluminescence compared to a 3D MAPbI3 thin film. Moreover, compared to the PPVs based on a 3D perovskite thin film, enlarged built-in potential, suppressed charge carrier recombination, boosted charge transport, and reduced charge carrier extraction time are observed from the PPVs based on the 2D/3D perovskite bilayer thin film post-annealed with solvent vapor. As a result, perovskite solar cells exhibit a power conversion efficiency of 22.13% and dramatically enhanced stability, and perovskite photodetectors show a photoresponsivity of 1.38 AW-1, detectivity of 6.52 × 1014 cm Hz1/2 W-1, and linear dynamic range of over 167 dB at room temperature. These results demonstrate that we develop a simple method to approach high-performance PPVs by the 2D/3D perovskite bilayer thin film.