Structures and luminescence properties of y at.% Eu3+-doped Y(Ta1−xPx)O4 phosphors

UV-activated phosphors Y(Ta1−xPx)O4:y at.% Eu3+ for solid state lighting were synthesized by high temperature solid-state method. The crystal structures and luminescent characteristics of Y(Ta1−xPx)O4:Eu3+ phosphors were investigated in detail. It is found that PO43− can enter into YTaO4 crystal structure with a maximum doping concentration of 1%. And the luminescence performances of Y(Ta1−xPx)O4:Eu3+ can be continuously improved with the increase of PO43− doping. Gauss fitting analysis demonstrates that the excitation bands of Y(Ta1−xPx)O4:Eu3+ are mainly composed of charge transfer bands of TaO43− (peak center is located in 230 nm) and Eu3+ (peak center is located in 250 nm) which indicates that TaO43− has energy transfer effect on Eu3+ 615 nm emission. The characteristic emissions of Eu3+ excited by 250 nm ultraviolet light occurred at 595 nm (assigned to 5D0→7F1) and 615 nm (assigned to 5D0→7F2), respectively. It is of particular note that the color coordinates of Y(Ta0.99P0.01)O4:Eu3+ in the yellow-red region can be modulated by changing the doping concentrations of Eu3+. And the optimum doping concentration of Eu3+ with the strongest luminous intensity and the highest color purity is 7 at.%.