Influence of Dy3+ coactivator on the luminescence properties of Gd2O2S:Tb3+ phosphor

Abstract

Gd2O2S:Tb, Dy phosphor were synthesized by co-precipitation method combined with solid-state reactions. The crystal structure and luminescent properties were investigated in this paper. It was confirmed that no new phase was introduced by the analysis of X-ray diffractions (XRD) and fluorescence spectroscopy. It was also illustrated that the lattice size was decreased by doping Dy3+ ions. The results showed that the Dy3+ coactivator had a remarkable influence on the spectral properties of the Gd2O2S:Tb phosphor and can be taken as rare earth ion detector to determine the micro-structure of phosphors. Especially the cross relaxation between Tb3+ and Dy3+ may take place to form the non-radiative energy transfer. Dy3+ as the coactivator added in Gd2O2S:Tb could enhance the luminescence and not disturb its other primary properties. With Dy3+ concentration increased, the intensity of 4F9/2—H13/2 transition at 578 nm was increased further and the emission of 5D4—7FJ transition was highly improved to cause greener emission.