Nanosized zinc gallate phosphors were prepared via the citric gel route and their luminous properties were characterized by photoluminescence in this study. From the results of X-ray diffraction studies, it was found that a spinel phase of ZnGa2O4 formed after the dry gel had been heat-treated at 470degreesC for I It and well-crystallized spinet phosphors with an average particle size of 35 nut were obtained after the dry gel had been heat-treated at 700degreesC for 5 It. The photoluminescence studies manifested that the shapes and the wavelengths of maximum intensity of the absorption and emission spectra were independent of the heat-treatment temperature in the range between 600 and 1000degreesC. Instead of the normally observed bell-shaped spectrum, peak-shaped emission spectra were observed when these nanosized phosphors were excited with UV light of wavelength of 254 nm. The peak-shaped emissions with maximum intensity at a wavelength of 470 run correspond to the self-activated luminescence of ZnGa2O4. (C) 2004 The Electrochemical Society.