Preparation and Characterization of Red-Luminescence Phosphors Ca _0.5Sr _0.5MoO ₄:Eu ³⁺ for White-Light-Emitting Diodes

A novel nano red-emitting phosphors Ca_0.5Sr_0.5MoO₄:Eu³⁺ were successfully synthesized via the sol–gel method using citric acid as a chelate. The resultant powders were characterized by X-ray diffraction, scanning electron microscopy, and photoluminescent spectroscopy. The results show that the particle size of the synthesized phosphors is about 700 nm. It also shows that the synthesized phosphor powders can be effectively excited at the wavelengths of 395 nm in ultraviolet light area and 467 nm in blue light area, and it has an intense red emission at 615 nm. Furthermore, the optimal concentration of Eu³⁺ in Ca_0.5Sr_0.5MoO₄:Eu³⁺ is about 10%, the best firing temperature is at 1 000 and the emission intensity becomes five times stronger as the introduction of Na ⁺ acting as charge compensation in Ca_0.5Sr _0.5MoO₄:Eu³⁺, 0.01 Na⁺. It is considered to be an efficient red-emitting phosphor for white light-emitting diodes (w-LEDs).