Effect of anion on the homogeneous precipitation of precursors and their thermal decomposition to zinc oxide

Abstract

The effect of using different anions (Cl-, SO42-, NO3-, and CH3COO-) during the synthesis of precursors to ZnO, by homogeneous precipitation, was studied. The precursors of ZnO were synthesized by homogeneous precipitation using various zinc salts, and urea as the precipitating agent. When Cl- and SO42- were used as the anions, single precursor phases were obtained, while the remaining anions (NO3-, and CH3COO-) produced mixed phases. All the precursors were calcined in air, based on their decomposition temperatures, to produce ZnO. The precursors and the oxides were characterized by an array of techniques including FT-IR, AAS, CHNS analysis, TGA, FE-SEM, TEM, UV-Vis spectroscopy, and XRD. The size and shape of the precursor particles and ZnO were found to depend on the anion used. The effect of varying the synthetic conditions such as concentrations of Zn2+ source and urea were also studied. © 2009 Elsevier B.V. All rights reserved.