Photo- and thermoluminescence properties of single-phase white light-emitting Y_(2-x)SiO_5:xDy~(3+) nanophosphor: a concentration-dependent structural and optical study

摘要

Despite high demand, the number of white light-emitting phosphors with single activator is limited. This is due to the fact that singly doped phosphors show no emission in the required spectral region to achieve white light. In the present study, we report the synthesis of single dopant (Dy3+) activated white light-emitting Y2SiO5 nanophosphor by one-step autoignition-based solution combustion method. The influence of Dy3+ concentration on the crystal structure, surface morphology and photoluminescence (PL) properties is investigated. The Y2SiO5:Dy3+ phosphor can be efficiently excited by near-UV radiation (390 nm) that results in the blue (482 nm) and yellow (572 nm) emission bands. The white light emission is achieved by mere variation of Dy3+ concentration. The color purity of the phosphor is confirmed by CIE coordinates (x = 0.295, y = 0.372). Thermoluminescence (TL) studies are carried out by using gamma radiation as excitation source, and highest intense TL glow curve is found for 5 mol% Dy3+-doped Y2SiO5. The intensity of the TL glow curves showed significant dependence on duration of gamma exposure. The TL intensity parameters, such as energy of activation, order of kinetics and frequency factors, were calculated and analyzed.