Sol–gel synthesis of red-emitting LiEuW2O8 powder as a near-ultraviolet convertible phosphor

LiEuW2O8 phosphor with the optical function of color conversion from near-UV to red wavelength was prepared by sol–gel method using inorganic salts as a starting material. Viscous mixing sol was prefired at 300 °C for 120 min in air and then white precursor was finally annealed at 800 °C for 240 min in Ar. Structural and photoluminescent properties of the sample were analyzed by an X-ray diffraction analysis, field emission-scanning electron microscope and a fluorescent spectrophotometer. The main emission peak is 5D0 → 7F2 transitions of Eu3+ at 615 nm, other transitions from the 5D0 → 7F1, 5D0 → 7F3 and 5D0 → 7F4 located at 570–700 nm range are weak. The characteristic emission of WO42− in LiEuW2O8 is quenched absolutely and only red-light emission of Eu3+ appears.