Luminescence properties of Ce 3+and Tb 3+ ions codoped strontium borate phosphate phosphors

Abstract

The Ce 3+-activated, Tb 3+-activated, and Ce 3+ and Tb 3+ co-activated phosphors 2SrO– nB 2O 3–(1− n)P 2O 5 were synthesized by the solid-state reaction. The structures, photoluminescent spectra and dynamics of them were systemically studied. The results demonstrate that the structure of the samples with n=0.10–0.50 belongs to the hexagonal phase. When n is beyond this range, the structures are the mixed phases of α-Sr 2P 2O 7 and Sr 2B 2O 5. The optimum composition is determined to be n=0.25 for the 2SrO– nB 2O 3–(1− n)P 2O 5 phosphors. As n varies from 0.01 to 0.50, the lifetime of Ce 3+ ion increases gradually, while the lifetime of Tb 3+ ion decreases, indicating that the energy transfer efficiency decreases with the increase of n. The ET efficiency between Ce 3+ and Tb 3+ in the optimum composition reaches to 70%. The present results demonstrate that the Ce 3+ and Tb 3+ co-activated hexagonal 2SrO–0.25B 2O 3–0.75P 2O 5 powders can possibly be applied as the newly developed green efficient phosphors in the field of lighting and display.