Zinc gallate and its starting materials in solid state reaction route- A comparative study

ZnGa2O4 belonging to the class of inorganic compounds with spinel structure is a self activated phosphor having wide applications in display devices. We report the synthesis and characterization of ZnGa2O4 using conventional solid state reaction method and a comparative study of its properties with commercial ZnO and Ga2O3 fired under similar conditions. XRD results proved that the zinc gallate phosphor is cubic in structure with an average grain size of 25 nm. Rectangular porous nature of zinc gallate phosphor is obtained from the SEM analysis. From the diffuse reflectance spectrum, the band gap of zinc gallate (4.74 eV) was evaluated to be between that of ZnO and Ga2O3. This ternary phosphor showed a bluish green emission with Commission International d’Eclairage (CIE) coordinates x = 0.26 and y = 0.36 under the excitation by UV light.