Tunable and enhanced luminescence of Ba2-xCaxSiO4-yN2/3y:Eu2+ phosphors for white light-emitting diodes

Color tuning and luminescence enhancement are predominant challenges for improving the performance of white light emitting diodes(LEDs) toward commercial application. In this paper, a novel promising BaCaSiON:Eutphosphors with tunable and enhanced luminescence for phosphors converted LEDs(pc-LEDs) have been successfully synthesized by a direct gas-reduction nitridation method. The effects of Ca and N doping on the phase purity, morphology and optical properties of BaCaSiON:Eutphosphors were also systematically investigated. The optical results show that BaCaSiON:Eutphosphors can be actively excited over a broad range from 250 to430 nm. With the adding of different concentrations of Cations in phosphors, the emission color wavelength can be tailored from 501 to 441 nm by a 375 nm NUV LED excitation source. Furthermore, it has been found that the emission and absorption of BaCaSiONtphosphor can be significantly improved when Nions were introduced into the host lattices. The intensity of BaCaSiON:Eutphosphor was 3.4 times higher than the phosphor without N doping. The fabrication and characterization of pc-LEDs using BaCaSiON:Eutphosphors-silica gel as the coating layer onto 375 nm-emitting In Ga N LED caps demonstrated the superior optical and current tolerant properties,making it a promising and competitive candidate for commercial utilization in white LED applications.