Synthesis of Nanocrystalline ZnGa2O4 Phosphor with Different Concentrations via a Precipitation Method

In this study, nanocrystalline zinc gallate (ZnGa2O4) phosphors were prepared by a precipitation method using aqueous ammonia as the precipitant. This method enabled the low temperature formation of phosphors with spherical shape. The samples were characterized by X-ray diffractometry (XRD), scanning electron microscopy (SEM), and cathodoluminescence (CL). The highest diffraction intensity was observed for the sample with a metal ion concentration of 0.1 mol/dm3. The sample with this metal ion concentration had nanocrystalline ZnGa2O4 phosphor with an average size of about 80 nm. The emission spectra of ZnGa2O4 showed a broad self-activated blue emission band spanning over in the wide range of 300–600 nm with a peak wavelength of about 420 nm; this band showed a maximum intensity at a metal ion concentration of 0.1 mol/dm3.