Preparation, electronic structure and luminescence properties of Ce~(3+)-activated CaZnOS under UV and X-ray excitation

摘要

The electronic structure of CaZnOS calculated using the CASTEP mode is an intermediate band gap semiconductor with a direct band gap of 2.4 eV. Ce~(3+)-activated CaZnOS samples were prepared by a solid-state reaction method at high temperature and their luminescence properties under UV-visible and X-ray excitation were investigated. CaZnOS:Ce~(3+) exhibits a broad band emission in the wavelength range of 450-650 nm, originating from the 5d-4f transition of Ce~(3+) for both under blue light (460 nm) and X-ray excitation. The mechanism of luminescence and concentration quenching of Ce~(3+) in CaZnOS have been investigated in detail. The results showed that the relative luminescence intensity reaches a maximum at 1 mol% of Ce~(3+), and the electric dipole-dipole interaction is the major mechanism for concentration quenching of Ce~(3+) emission in CaZnOS. The potential application of CaZnOS:Ce~(3+) has been pointed out.