Morphology conversion and highly enhanced green emission of ZnO phosphors by annealing of ZnS in KC1 flux

摘要

KCl flux has been used to enhance the green emission of the ZnO phosphors prepared by direct annealing of ZnS powders in air. Compared with the ZnO powders obtained without using KC1 flux, the morphology of as-prepared powders was changed from spherical clusters to "hexagonal prisms". In addition, the intensity of the green emission was enhanced approx 5 times, as well as a clear red-shift (approx 30 nm) in excitation band with a new excitation level located at 380 nm was found. The significant enhancement of the green emission observed from the ZnO phosphors prepared with KCl flux is ascribed to the morphology conversion and the shift in the maximum excitation wavelength induced by the incorporation of Cl~- ions into ZnO lattice.