High-Performance Industrial-Grade CsPbBr3 Single Crystal by Solid-Liquid Interface Engineering.

Abstract

All-inorganic metal halide perovskite CsPbBr3 crystal is regarded as an attractive alternative to high purity Ge and CdZnTe for room temperature γ-ray detection. However, high γ-ray resolution is only observable in small CsPbBr3 crystal; more practical and deployable large crystal exhibits very low, and even no detection efficiency, thereby thwarting prospects for cost-effective room temperature γ-ray detection. The poor performance of large crystal is attributed to the unexpected secondary phase inclusion during crystal growth, which traps the generated carriers. Here, the solid-liquid interface during crystal growth is engineered by optimizing the temperature gradient and growth velocity. This minimizes the unfavorable formation of the secondary phase, leading to industrial-grade crystals with a diameter of 30mm. This excellent-quality crystal exhibits remarkably high carrier mobility of 35.4cm2 V-1 s-1 and resolves the peak of 137 Cs@ 662keV γ-ray at an energy resolution of 9.91%. These values are the highest among previously reported large crystals.