Enhanced photoluminescence and stability of ZnSe microspheres/Cs4PbBr6 microcrystals/CsPbBr3 nanocrystals composites

摘要

A ternary complex combining dual-phase perovskites-Cs4PbBr6/CsPbBr3(DP-CPB) with ZnSe micropshere s(ZnSe-DP-CPB) was succes s fully prepared using supersaturated recrystallization technique at room temperature.It was showed that the DP-CPB composites were partially embedded in ZnSe microsphere composed with ZnSe NCs.The light absorption range of ZnSe-DP-CPB composites was extended from visible to near infrared light.Highly enhanced luminescence from ZnSe-DP-CPB composite was observed and the excitation power-dependent photoluminescence showed that the recombination involves excitons.The recombination lifetimes of the ternary composites increased compared with DP-CPB composite,indicating that the non-radiative combination was suppressed which maybe possibly due to the decrease of both bulk and surface defects,owing to the passivation of ZnSe,as well as the suitable band alignments of these three components.The ternary complex also showed improved stability of photoluminescence(PL),which opens a newavenue for enhancing the stability of PL and optoelectronic applications for semiconductor-perovskite composites.