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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 Ba_(2-x)Ca_xSiO_(4-y)N_(2/3y):Eu~(2+) tphosphors 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 Ba_(2-x)Ca_xSiO_(4-y)N_(2/3y):Eu~(2+) tphosphors were also systematically investigated. The optical results show that Ba_(2-x)Ca_xSiO_(4-y)N_(2/3y):Eu~(2+) tphosphors can be actively excited over a broad range from 250 to430 nm. With the adding of different concentrations of Ca~(2+) tions 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 Ba_(2-x)Ca_xSiO_(4-y)N_(2/3y) tphosphor can be significantly improved when N~(3-) ions were introduced into the host lattices. The intensity of Ba_(1.5)Ca_(0.5)SiO_(4-y)N_(2/3y):Eu~(2+) tphosphor was 3.4 times higher than the phosphor without N doping. The fabrication and characterization of pc-LEDs using Ba_(2-x)Ca_xSiO_(4-y)N_(2/3y):Eu~(2+) tphosphors-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.
Color shifting 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 Ba 2-x Ca x SiO 4-y N 2y: Eu 2+ tphosphors 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 (2-x) Ca_xSiO_ (4-y) N_ (2 / 3y): Eu ~ (2+) tphosphors were also systematically investigated. The optical results show that Ba_ (2-x) Ca_xSiO_ (4-y) (2 / 3y): Eu 2+ tosphors can be excited excited over a broad range from 250 to 430 nm. With the addition of different concentrations of Ca 2+ tions in phosphors, the emission color wavelength can be tailored from 501 to 441 nm by a 375 nm NUV LED excitation source. Further, it has been found that the emission and absorption of Ba_ (2-x) Ca_xSiO_ (4-y) N_ (2 / 3y) The intensity of Ba_ (1.5) Ca_ (0.5) SiO_ (4-y) N_ (2 / 3y): Eu ~ (2+) tphosphor was 3.4 times higher than the phosphor without N doping. The fabrication and characterization of pc-LEDs using Ba_ (2-x) Ca_xSiO_ (4-y) N_ (2 / 3y) as the coating layer onto 375 nm-emitting In Ga N LEDs capsulated the superior optical and current tolerant properties, making it a promising and competitive candidate for commercial utilization in white LED applications.