Growth and performance of CsCu(Br, Cl)3 single crystals

This paper presents the growth of large-sized CsCu(Br, Cl) 3 crystals using the aqueous solution evaporation method. The structure and the components of the crystals were analyzed. It was found that CsCuBr 3 is a direct bandgap material, while CsCuCl 3 is an indirect bandgap material, and the band gap of CsCu(Br, Cl) 3 halides can be adjusted in the range of 2.63–3.63 eV (PBE) by changing the ratio of Br - /Cl - . Besides CsCuCl 3, which has an absorption valley at 654 nm, the other CsCu(Br, Cl) 3 crystals show high absorption in the range of 200–1000 nm. Under UV excitation, the PL spectra show that CsCu(Br, Cl) 3 crystals exhibit red and blue emission.