Structural, Electronic, and Magnetic Properties of NiGa2O4

In this study, NiGa2O4 phase is prepared using a sonication-assisted hydrothermal method. Rietveld-fitted x-ray diffraction results reveal the formation of a single-phase compound with average crystallite size of ~32.5 nm. UV-visible absorption spectroscopy results show bandgap energy of 4.1 eV. X-ray absorption near-edge structural analysis confirms the presence of Ga3+ and Ni2+ ions in Ga2NiO4. The magnetic properties of NiGa2O4 phase are studied at two temperatures (i.e., 50 K and 300 K), and the NiGa2O4 phase is found to be paramagnetic. The origin of magnetism in the NiGa2O4 phase is mechanistically discussed by considering the plausible magnetic interactions among the constituent ions in the compound.