Synthesis and characterization of ZnGa2O4 particles prepared by solid state reaction

We employed solid state reaction technique to synthesize ZnGa2O4 particles, produced in steps of mixing/milling the ingredients in H2O following thermal treating under 1200 degrees C. We compare spinel and partially inverse spinel structure in ZnGa2O4 particles using Rietveld refinement. Crystal structure of ZnGa2O4 particles was identified with two structural phases; normal spinel structure and partially inverse spinel structure using Rietveld refinement. It is found that the partially inverse spinel structures occupy nearly 13% and the rest is normal spinel structure. The obtained X-ray diffraction data show that lattice constant and the position of Oxygen atoms remain almost constant in both structures. The characterization of the particles was also improved using X-ray photoelectron spectroscopy and Fourier transforms infrared spectroscopy measurements. The optical analyses were done with UV-visible spectroscopy. The band gap, calculated from climate point of UV-visible data, was found as 4.6 +/- 0.1 eV. Despite no unexpected compound (such as ZnO and Ga2O3) in the structure, the optical analyses were shown defective ZnO structure in ZnGa2O4. (C) 2012 Elsevier B.V. All rights reserved.