A new potential green-emitting erbium-activated α-Na3Y(VO4)2 nanocrystals for UV-excitable single-phase pc-WLED applications

Abstract

A potential UV-excitable green-emitting erbium-doped α-Na3Y(VO4)2 nanocrystalline phosphor has been successfully synthesized via facile citrate-based solution combustion method. The structural characterization of the sample was carried out using X-ray diffraction, TEM, HRTEM, SAED, EDS and FTIR analysis. The phosphor exhibits green emission at 523 nm and 552 nm, which correspond to 2H11/2 → 4I15/2 and 4S3/2 → 4I15/2 transitions of Er3+, respectively. The energy transfer mechanism among Er3+ ions and the concentration mechanism have been studied. The optimal doping concentration of Er3+ in the α-Na3Y(VO4)2 is found to be 0.025 mol. The non-radiative interaction among Er3+ is attributed to the dipole–quadrupole interaction. The quantum yield is found to be 7.25%, and chromaticity coordinates for the optimal concentration are found to be (0.2571, 0.6707) which are close to National Television System Committee standards for green (0.21, 0.71). The lifetime of erbium emission is found to be in microsecond range. The photoluminescence studies reveal that the newly synthesized Er3+-doped α-Na3Y(VO4)2 nanocrystals would be a good choice as green emitter to be combined with previously investigated blue- and red-emitting Tm3+- and Sm3+-doped α-Na3Y(VO4)2 nanocrystals for realizing RGB phosphor.