Synthesis and Luminescence Characteristics of CaWO4: Eu3+ Red Phosphor for White Light Emitting Diode

Abstract

White light emitting diode (LED) red phosphor Ca1−xWO4:xEu3+ (x = 0.10, 0.15, 0.20, 0.25, 0.30) was prepared by high temperature solid state method. The phase of the phosphor sample was analyzed by X-ray diffraction (XRD) and the morphological characteristics of the sample were analyzed by scanning electron microscope (SEM), and the luminescence characteristics of the sample were studied by fluorescence spectrophotometer. The results show that the synthesized samples are scheelite structure and can be effectively excited by near ultraviolet light (393 nm) and blue light (464 nm). The main emission peak is located at 615 nm, which belongs to the 5D0→7F2 transition of Eu3+. The optimum doping amount of Ca1−xWO4:xEu3+ is 25%. In addition, Ca0.75WO4: Eu3+0.25 was prepared by sol–gel method, which was compared with the same component sample prepared by high-temperature solid-state method. It was found that the phosphor prepared by high-temperature solid-state method had relatively high luminous intensity.