Optical Property of Inorganic Halide Perovskite Hexagonal Nanocrystals

Inorganic halide perovskite nanocrystals (NCs) exhibit many excellent optical and semiconductor properties. Herein, CsPbBr3 hexagonal NCs (HNCs) have been synthesized, and their photophysical behavior has been investigated in detail. The CsPbBr3 cubic NCs (CNCs) act as references. The CsPbBr3 HNCs exhibit apparent linear and two-photon fluorescence properties, and their two-photon absorption cross section is 4668.7 GM. In addition, the energy band, radiative channel, and carrier recombination of CsPbBr3 HNCs have been analyzed compared to those of CsPbBr3 NCs by changing the temperature and pressure. The photoluminescence (PL) property of CsPbBr3 HNCs is always better than that of CsPbBr3 CNCs since their electron–hole bimolecular recombination related to PL is much rapid. Our results provide comprehensive insights into the photophysical properties of inorganic halide perovskite nanomaterials and examine their potential in the optoelectronic field.