Luminescent properties and energy transfer in novel single-phase multicolor tunable Sr3Y(BO3)3:Tb3+,Eu3+ phosphors

Abstract

A novel multicolor tunable phosphors Sr3Y(BO3)3:xTb3+,yEu3+ (SYBO:xTb3+,yEu3+) had been obtained by conventional solid state reaction. The XRD patterns, scanning electron microscope (SEM) and the luminescence spectral were used to explore the phase composition and crystal structure, luminescence properties as well as the energy transfer and fluorescence lifetimes in detail. Under 376 nm wavelength excitation, the phosphors included green and red color derived from the representative emission wavelengths of the Tb3+ and Eu3+, respectively. Both the luminescence spectral and the fluorescence lifetimes demonstrated energy transfer in the SYBO:xTb3+,yEu3+ phosphors. When the doped Eu3+ concentration was 0.5 mol, the energy transfer efficiency was as high as 96.48% and 98.34%, respectively. Moreover, the energy transfer mechanism from Tb3+ to Eu3+ in the SYBO:xTb3+,yEu3+ phosphors was proved to be the dipole–dipole interaction. With the increase of the Eu3+ concentration, the color of the SYBO:xTb3+,yEu3+ phosphors could tune from green to light-white, and then to red owing to the existing energy transfer. Those results indicated that the SYBO:xTb3+,yEu3+ phosphors could be as promising multicolor tunable candidates for WLEDs under UV light.