Mechanochemical Synthesis and Thin-Film Deposition of Zero-Dimensional Cesium Lead Mixed-Halide Perovskites for Wide-Range Color-Tunable Emission

Metal-halide perovskites possess synthetic tunability in terms of their compositions and structures, which results in a facile control of the properties crucial for optoelectronic device applications. For instance, the optical band gap of perovskites can be adjusted by means of halide compositions, which can generate a wide range of perovskite phases emitting visible light from purple to red. Furthermore, embedding the emissive perovskites within inorganic structural matrices provides further opportunities to tune their functionalities. In this study, we demonstrate that mechanochemical synthesis (MCS) can be successfully employed to prepare a full range of mixed-halide zero-dimensional (0D) perovskites (Cs 4 PbCl m Br 6– m and Cs 4 PbBr 6– m I m, where m is an integer from 0 to 6). The synthesized mixed-halide 0D perovskite powder samples exhibited photoluminescence emissions spanning the entire visible spectrum (410–690 nm), which likely originates from the inclusion of three-dimensional perovskites. Furthermore, we demonstrate that our 0D perovskite powder samples can be readily used as the source for fabricating thin films via fast single-source vacuum deposition while preserving the optical properties of the source powder samples. Overall, our study reveals the versatility of MCS as a useful toolkit for preparing a family of 0D perovskites with a full range of halide compositions with potential for light-emitting applications.