Luminescence and structure of a novel red-emitting phosphor Eu3+-doped tellurate garnet Li3Y3Te2O12

Eu3+-doped red-emitting phosphors of tellurate garnets Li3Y3−3xEu3xTe2O12 (x = 0.05–1) were synthesized by the solid-state reaction. The phase purity of the as-prepared phosphor was verified by X-ray diffraction (XRD) studies. The photoluminescence excitation and emission spectra, the fluorescence decay curves, the dependence of luminescence intensity on doping level and CIE coordinates were investigated. The phosphor can be efficiently excited by near UV and blue light to realize an intense narrow red emission line (611 nm) corresponding to the forced electric dipole transition 5D0 → 7F2 of Eu3+ ions. The potential application as a red-emitting phosphor for solid state lighting was evaluated in comparison with Eu3+-doped Y2O2S and aluminum garnet phosphors. The phosphor can be suggested to be a potential red-emitting candidate for the application in white LEDs under the irradiation of near-UV or blue chips.

► A novel red-emitting phosphor on the base of tellurate garnet Li3Y3Te2O12 was developed.
► A potential candidate for the application on near-UV white LEDs.
► The excellent red luminescence properties were discussed on the base of the special garnet structure.
► The microstructure of Eu3+ ions has a great influence on the red luminescence.