Highly enhanced photoluminescence from perovskite-semiconductor composites formed by CsPbBr3 nanocrystals embedded in ZnSe microsphere

Perovskite-semiconductor composites formed by high quality CsPbBr 3 nanocrystals embedded in ZnSe microsphere were prepared. The optical properties of pure CsPbBr 3 and composites were studied in detailed. Highly enhanced luminescence from CsPbBr 3 -ZnSe composites was observed and the excitation power-dependent photoluminescence of samples showed that the recombination in all samples involves excitons . The recombination lifetimes of composites for both fast and slow decays increased compared with pure perovskite, indicating that the nonradiative combination was suppressed which may be possibly due to the decrease of both bulk and surface defects , owing to the passivation of ZnSe. Besides, the visible light absorption range of composites was extended, which suggests increasing efficiency of photoelectric conversion and the utilization of sunlight.