A tunable single-component warm white-light Sr3Y(PO4)3:Eu2+,Mn2+ phosphor for white-light emitting diodes
The photoluminescence properties and energy transfer of the Eu2+ and Mn2+ co-doped Sr3Y(PO4)3 phosphors are investigated in detail. Two main emission bands attributed to the Eu2+ and Mn2+ ions are observed under UV light excitation via an efficient energy transfer process. When the Eu2+ doping content is fixed, the emission chromaticity can be varied by simply adjusting the content of Mn2+. The study of the behavior as a function of doping concentration indicates that the warm white-light can be obtained in a single host lattice. Furthermore, the analysis of the fluorescence decay curves based on the Inokuti–Hirayama theoretical model reveals that the dipole–quadrupole interaction is mainly responsible for the energy transfer mechanism from the Eu2+ to Mn2+ ions in the Sr3Y(PO4)3 phosphor. The developed phosphor exhibits a strong absorption in UV spectral region and white-light emission which may find utility as a single-component white-light-emitting UV-convertible phosphor in white LED devices.