Solvent-induced growth of ZnO microcrystals

A simple route was reported to synthesize various morphological ZnO by selecting different solvents as reaction medium under solvothermal condition. Column-like ZnO microcrystals were obtained in monohydric alcohol, while polyhedral spherical ZnO formed when ethylene glycol with two hydroxyl groups was selected. In order to estimate the basic effect of OH, ethanolamine with OH and NH2 functional groups was used as solvent, melon seed-like ZnO were prepared. Besides, other morphological ZnO were synthesized in mixture solvents. The results showed that selected solvents played a crucial role in controlling the ZnO morphologies and acted as templates for the growth of ZnO microcrystals. The morphological difference of as-obtained microcrystals strongly depended on the specific functional groups of solvent media, such as hydroxyl group (OH), amino group (NH2) and carbonyl group (CO).