Luminous properties of highly moisture-resistant Dy3+-Tm3+-Eu3+ co-doped phosphate glasses for W-LED

Abstract

In this study, the high-temperature melt quenching method was used to create Dy3+-Tm3+-Eu3+ co-doped P2O5–CaO–K2O–ZnO series glasses (abbreviated PCKZ glasses). The samples were then subjected to various analyses such as X-ray diffraction, thermo-temperature property analyses, chemical stability analysis, Raman spectroscopy analysis, absorption spectroscopy, photoluminescence spectroscopy, fluorescence decay lifetime and CIE chromaticity coordinates to determine the structure and luminous properties of the glass. The sample’s density was determined, and the molar volume was calculated. The results reveal that the PCKZ series glasses prepared in this study are structurally stable and resistant to moisture. Following the addition of Eu3+ to the glass, the emission spectra revealed red emission from Eu3+ at 613 nm. The emission bands of Dy3+ and Tm3+ were enhanced as the concentration of Eu3+ increased, indicating an energy transfer between Eu3+ and Dy3+-Tm3+. The energy was fitted using the Inokuti-Hirayama (I–H) model resulting in energy transfer in dipole-dipole mode. Notably, the glass prepared in this study shows good moisture resistance and chemical stability, as well as emitting bright warm white light when exposed to 350 nm UV light excitation. Under UV simulation at 350 nm, the glass with the composition 50P2O5– 12CaO– 5K2O– 33ZnO-0.5Dy2O3-0.6Tm2O3-0.09Eu2O3 produces white light with a white colour temperature of 4954 K, colour coordinates of (0.3498, 0.3744), a long fluorescence lifetime of 0.498 ms, the quantum yield is 6.86 %, and it has good thermal stability. Therefore, it is considered that PCKZ: DTE (1, 2, 3) series glasses can be used in high humidity-resistant W-LEDs.