Effects of Bi3+ co-doping on structure and luminescence of SrZn2(PO4)2-based phosphor

In this study, novel orange-red-emitting SrZn2(PO4)2-based phosphors have been synthetized by solid-state reaction. The effects of Bi3+ co-doping on structure and luminescence of SrZn2(PO4)2-based phosphors are first explored based on theoretical arithmetic and experimental researches. The results show that Bi3+ co-doping increases the conductivity and absorbance of SrZn2(PO4)2 matrix. SrZn2(PO4)2:Eu3+, Bi3+ phosphors monitored at 393 nm exhibits an orange-red emission and the excitation wavelength matches the output wavelength of near-ultraviolet chips. In addition, one can find that the emission intensity of Eu3+ can be increased by adjusting Bi3+ doping concentration due to the energy transfers from Bi3+ to Eu3+ in SrZn2(PO4)2 matrix, and the optimized Bi3+ doping concentration is 2%. The obtained phosphor SrZn2(PO4)2:Eu3+, Bi3+ has a potential application in light-emitting diodes excited by near ultraviolet light.