Synthesis of ZnO submicron spheres by a two-stage solution method

Abstract

This paper presents a two-stage method to synthesize the mono-dispersed ZnO spheres. The size and uniformity of ZnO spheres can be controlled in the sub-micrometer range. This makes the method applicable to the fabrication of photonic crystal structures. The effects of different reaction parameters such as reaction temperatures, reaction times, and water concentrations on the formation of ZnO spheres were investigated. On the basis of the experimental results, we discuss and propose a possible mechanism to elucidate the formation of ZnO submicron spheres. Furthermore, the room temperature photoluminescence (PL) measurements of the products were carried out to investigate their optical properties. The PL results showed that the ZnO submicron spheres exhibited a strong ultraviolet emission and a broadband green emission in the visible region.