A novel blue-emitting Ba5(BO3)2(B2O5):Ce3+ phosphor for application in near-UV white LEDs

Abstract

The blue-emitting phosphor Ba5(BO3)2(B2O5):Ce3+ was synthesized by a high-temperature solid-state method. Its crystal structure, luminescence properties, concentration-quenching mechanism and thermal stability were investigated. This phosphor can be effectively excited by 351-nm near-ultraviolet light, with a broad blue emission band. The emission spectra of the Ba5(BO3)2(B2O5):Ce3+ phosphor were clearly monitored with critical emission quenching as a function of the Ce3+ content. It was further proven that the energy transfer among the nearest-neighbor ions results in the concentration quenching of Ce3+ in Ba5(BO3)2(B2O5). The dependence of the luminescent intensity on the charge-compensated (Li+, Na+, K+) was also discussed. Ba5(BO3)2(B2O5):Ce3+ phosphors can be effectively excited by near-UV light and simultaneously exhibit excellent luminescence resistibility against thermal quenching in the temperature range from 300 to 400 K. The activation energy ΔE is calculated to be 0.21 eV. The present work suggests that the Ba5(BO3)2(B2O5):Ce3+ phosphor is a promising material for near-UV chip-based white LEDs.