Preparation of Dy3+/Tm3+ Co-doped Phosphate Glasses by Melt Method and its Luminescence Properties

Abstract

In this paper, P2O5 matrix materials were used to prepare Dy3+/Tm3+ phosphate glasses with different concentrations by high temperature melt method. The emission spectrum of Dy3+/Tm3+co-doped glass samples were measured under 350nm excitation. High-efficiency green and blue down-conversion emissions were already observed. Based on the intensity of the emission peaks of samples doped with different concentrations of Dy3+/Tm3+, It can be assumed that an energy transfer process is occurring between Dy3+/Tm3+, i.e. the energy transfer process between the two kinds of ions is Dy3+ to Tm3+ and Tm3+to Dy3+, respectively. Finally, the energy transfer between Dy3+/Tm3+ was further illustrated by testing the fluorescence decay lifetime of the samples. It was found that the increased probability of cross relaxation of ions in glasses doped with 0.8mol% Dy3+/0.2mol% Tm3+ caused the fluorescence quenching of Dy3+ ions, and a fluorescence color shift from blue to white was observed in the range of 0.2-0.7mol% Dy3+. CIE coordinates of the 0.2mol% Tm3+/0.7mol% Dy3+ co-doped phosphate glasses sample are (0.33, 0.32), which is extremely approximate to the standards of equivalent energy white light for illumination (0.33,0.33). The results indicate that Dy3+/Tm3+ has a significant contribution in the down-conversion mechanism.