Three- and two-dimensional mixed metal halide perovskites for high-performance photovoltaics

Three-dimensional (3D) metal halide perovskites (MHPs) incorporated with two-dimensional (2D) MHPs have been demonstrated to be a facile way to approach the high performance of perovskite photovoltaics (PPVs). In this study, we report high-performance PPVs, in terms of efficiency, detectivity, stability, and photocurrent hysteresis, based on the 3D mixed with 2D MHPs composites (termed as the 2D:3D mixed MHPs composites), where 4-fluoro-phenethylammonium, which possesses larger dipole moment compared to phenethylammonium, is used to create 2D MHPs. Systematically studies indicate that the 2D:3D mixed MHPs composites possess larger crystals, higher crystallinity, and enhanced charge transport compared to 3D MHPs thin film. As a result, the PPVs based on the 2D:3D mixed MHPs composites exhibit over 21.16 +/- 0.53% power conversion efficiency with suppressed photocurrent hysteresis, over 1016 cm Hz1/2W-1 detectivity, and dramatically boosted stability. Our results indicate that we provide a facile way to approach high-performance PPVs.