Single phase M+ (M = Li, Na, K), Dy3+ co-doped KSrBP2O8 white light emitting phosphors

A series of KSr1−xBP2O8:xDy3+ (0 ⩽ x ⩽ 0.09), and M+ (M = Li, Na, K) and Dy3+ co-doped KSrBP2O8 samples were synthesized by a solid state method for the first time. Their photoluminescence properties were investigated. Strong excitation peaks of KSrBP2O8:Dy3+ were found around 340–400 nm. Under the excitation of 345 nm, the phosphor can efficiently absorb UV light and emit white light by combining the blue light (∼480 nm) and yellow light (∼567 nm) emission peaks arising from f–f transitions of Dy3+. The optimal doping concentration of Dy3+ is found to be 5%, whose CIE chromaticity coordinates and corrected color temperature are respectively (0.357, 0.418) and 4846 K. Furthermore, the emission intensity of KSrBP2O8:Dy3+ can be enhanced by introducing the compensator charge M+ (M = Li, Na, K) without largely changing the CIE chromaticity coordinates and corrected color temperature. The results indicate that KSrBP2O8:Dy3+, M+ (M = Li, Na, K) may be a promising white light phosphor for white light-emitting diodes.