A novel one-step method to synthesize nano/micron-sized ZnO sphere

This paper presents a novel one-step method to synthesize nano/micron-sized ZnO spheres assembled from the aggregation of nano-particles. It was observed that ZnO spheres with controllable diameter were obtained when various volume ratios of triethanolamine (TEA) to H2O were used. Increasing the volume ratio of TEA to H2O could favor the formation of densely packed ZnO spheres. The UV–vis absorption spectra show that the absorption peak red-shifts with the increasing average diameter of the spheres. On the basis of the experimental results, we proposed a possible mechanism to elucidate the formation of ZnO spheres.