Fig. 3From: Controlled Hydrothermal Synthesis and Photoluminescence of Nanocrystalline ZnGa2O4:Cr3+ MonospheresFE-SEM micrographs showing morphologies of the 2ZGC products obtained by 24 h of hydrothermal reaction at 180 °C and pH = 9. The Cit3−/M (M total cation) molar ratios are a 0.5, b 1, c 1.5, and d 2.0Back to article page