Zinc Oxide Nanostructures by Solvothermal Synthesis

Abstract

The synthesis, characterization, and properties of three types of one-dimensional zinc oxide nanostructures are described. They were obtained by solvothermal treatment of nanometric zinc oxide as zinc ion source (i.e., starting from pure oxide), from a mixture of the oxide with stearic acid, and from intercalated oxide in the layered nanocomposite ZnO(stearic acid)0.38. The reactions were performed at 180◦C in a (1:1) ethanol/water mixture. Depending on the precursor and reaction times, morphologically homogenous phases corresponding to ZnO nanoneedles, nanorods or nanowires were obtained. Photoluminescence emissions were observed and are attributed to exciton transitions and to the presence of intrinsic defects such as oxygen and zinc interstitials. The band gap energies (Eg) were comparable to the values of bulk ZnO. The prepared nanostructures showed photocatalytic activities with respect to the degradation of methylene blue which were comparable to that of bulk zinc oxide.