Combustion synthesis and photoluminescence properties of CaZrO3: Eu3+ with highly enhanced brightness by Li+ doping

Eu3+, Li+ co-doped CaZrO3 nanocrystals composed of perovskite structure have been prepared by sol-gel-combustion method at 700 °C using ammonium nitrate as a fuel and citric acid as a complexing agent. No additional annealing was required, as crystalline CaZrO3 resulted directly from the combustion reaction. The structure and morphology were characterized by X-ray diffraction (XRD) and scanning electron microscope (SEM). The photoluminescence properties were measured using an Edinburgh FLS920 at room temperature. Stable orange-red emission from 550 nm to 630 nm has been observed from CaZrO3 crystalline phase. The incorporation of Li+ ions into CaZrO3 lattice could induce a remarkable increase of photoluminescence intensity by about three times. The mechanism of the enhanced emission by Li+ doping was discussed. The strong and color-uniform fluorescence images of the doped samples confirmed the potential applications of the phosphors in luminescence devices.