Effects of Anion on the Morphologies of ZnO Synthesized by an Aqueous Solution Method

ZnO were rapidly synthesized using different zinc salts (Zn(NO3)2, Zn(CH3CO2)2, ZnCl2 and ZnSO4) by an aqueous solution method at 90°C. The products were characterized by X-ray diffractometry and scanning electron microscopy. The results show that the anions have remarkable effects on the morphologies of ZnO. When Zn(NO3)2, Zn(CH3CO2)2 or ZnCl2 was used, ZnO was obtained with ellipsoidal, under-developed ellipsoidal and nano-particles morphologies, respectively. In the case of ZnSO4, layered basic zinc sulfate was obtained. The remarkable effects of anions on ZnO can be ascribed to the adsorption of the anions on the surface of ZnO, which hinders the further growth of ZnO nuclei. The effect of SO42- was further investigated by changing the mole ratio of SO42- to NO3-.