Photoluminescence investigation of novel reddish-orange phosphor Li2NaBP2O8:Sm3+ with high CP and low CCT

The exploration of appropriate inorganic phosphors with high color purity (CP) and low correlated color temperature (CCT) has always been a hot issue for solid state light applications. In this work, we have developed series of Sm3+ doped Li2NaBP2O8 (abbreviated as: LNBP) phosphors by means of the solid state synthesis route. The crystalline phase compositions, micromorphology, valence state of elements as well as photoluminescence properties were systematically illustrated. Upon the excitation wavelength at 400 nm, emission peaks are located at 561, 597, 643 and 699 nm, corresponding to the (4)G(5/2) -> F-6(5/2), H-6(7/2), H-6(9/2) and H-6(11/2) transitions of Sm3+ in the same order. The optimal doping amount of Sm3+ ions is 2 mol% for the reddish-orange photoluminescence of the LNBP:Sm3+ phosphor system. The critical energy transfer distance, mechanism of concentration quenching, CIE chromaticity coordinate, CP, CCT and internal quantum efficiency were extensively investigated. The title product might be considered as a promising candidate of phosphor in near UV-based warm white LEDs.