Photoluminescence and Thermoluminescence Properties of Nanophosphors, YVO4:Eu3+ and YVO4:Eu3+:Dy3+

Abstract

The as-synthesized, europium-doped, yttrium orthovanadate nanostructures exhibited photoluminescence properties that can vary based on the preparation conditions. All the samples exhibit red emissions, and the strongest emission band was observed at 620 nm and assigned to the 5D0 → 7F2 transition of Eu3+. The high intensity of the band is a consequence of the lack of inversion symmetry at the Eu3+ site (D2d symmetry) in the host lattice. The optimal europium doping concentration was 6 mol% for both preparation methods. These samples were annealed to obtain micro and nanoscale crystallite sizes in a range of 7.56 nm to 132.65 nm, and the emission spectra were obtained. The results revealed that the photoluminescence (PL) properties were dependent on crystallite size, the PL quantum yield measurements increased with increasing crystallite size. The introduction of the dopant ions induced changes in the TL glow curve structure and the kinetic properties, modifying the radiative recombination efficiency. The TL results suggest that both europium and europium-dysprosium doped YVO4 nanocrystalline phosphor present good potential for β-irradiation dosimeter applications.