Na1. 88Bi1. 88S4 and Na1. 36Ca1. 28Bi1. 36S4 Single Crystals: Growth, Structure and Optical Property

摘要: Na1. 88Bi1. 88S4 and Na1. 36Ca1. 28Bi1. 36S4 single crystals of high quality were successfully synthesized by solid-state reaction method using NaI as flux. Both compounds crystallize in the rocksalt structure type of a cubic Fm-3m space group. The preferred orientation growth of lattice face (111) were observed in both two compounds. The optical absorption measurements show that the band gap of Na1. 88Bi1. 88S4 and Na1. 36Ca1. 28Bi1. 36S4 compounds are 1.29 eV and 1.45 eV, respectively. Two compounds were fabricated into devices that exhibit notable photoelectric behavior, suggesting their potential for applications as photoelectric switches.