Perovskite CsPb₂Br₅ Microplate Laser with Enhanced Stability and Tunable Properties

Recent years have witnessed a surge of research in all-inorganic perovskite nanomaterials for solar cells and light emitting diodes due to their higher chemical stability compared to their hybrid organic–inorganic counterparts. Herein, by combining material synthesis, characterization, optical measurement, and density functional theory based first principles calculation, a type of all-inorganic perovskite CsPb₂Br₅ microplate with superior crystallinity, enhanced stability, and tunable optical properties is reported. With a robust band gap of ≈2.44 eV, CsPb₂Br₅ microplate exhibits low-threshold amplified spontaneous emission under both one- and two-photon excitation, which is related to its unique spatially distinguished valence/conduction band edge states originating from the intrinsic sandwiched structure. These results are expected to shed new light on future design and development of novel perovskite nanomaterials for optoelectronic devices.