Tunable white light and energy transfer of Eu 2+ ‐Tb 3+ ‐Eu 3+ tri‐activated glasses synthesized in air

Abstract An ever increasing demand for white light‐emitting diodes (W‐LEDs) results in the gradual growth of research on functionalized luminescent glasses. In this paper, single‐composition tunable white‐emitting Eu 2+ ‐Tb 3+ ‐Eu 3+ tri‐activated glasses were synthesized by melt quenching method without additional reducing atmosphere. The coexistence of Eu 2+ and Eu 3+ was confirmed by ultraviolet‐visible transmission spectra, photoluminescent spectra, fluorescence decay curves, and X‐ray photoelectron spectroscopy. Tb 3+ can act as bridge to connect Eu 2+ ‐Eu 3+ luminescent centers by energy transfer. Tone‐tunable white light can be achieved by coupling the emission centered at 412, 541, and 612 nm contributed from Eu 2+ , Tb 3+ , and Eu 3+ , respectively. By adjusting the relative content of Eu 2+ /Tb 3+ /Eu 3+ , ideal chromaticity coordinates of (0.33, 0.33) can be achieved under excitation of ultraviolet light. High thermal stability and tiny chromaticity shift were exhibited in samples. These results suggest that Eu 2+ ‐Tb 3+ ‐Eu 3+ tri‐activated glasses have great potential application in ultraviolet‐driven W‐LEDs.