Carrier dynamics in CsPbI3 perovskite microcrystals synthesized in solution phase

Abstract

All-inorganic cesium lead halide perovskites (CsPbX3, X=Cl-, Br-, I-) could provide comparable optoelectronic properties as a promising class of materials for photovoltaic cell (PV), photodetector and light-emitting diode (LED) with enhanced thermal and moisture stabilities compared to organic-inorganic lead halide species. However, fabrication of CsPbI3 perovskite via facile solution process has been difficult due to instability of CsPbI3 in the perovskite cubic phase in ambient air. Herein, we report the synthesis of CsPbI3 perovskite microcrystals by low-temperature, catalyst-free, solution-phase method. By applying the time-resolve spectroscopic technique, we determine the carrier diffusion coefficient of 0.6–1.2cm2/s, the intrinsic carrier lifetimes of 200–1300ns and diffusion length of 4–10μm in different individual CsPbI3 perovskite microcrystals. Our results suggest the CsPbI3 perovskite microcrystals synthesized by solution process exhibit high quality feature and are suitable for applications in optoelectronic devices.