Controllable synthesis and characterization of porous Zn/Cu composite hollow microspheres via a template-free route

Abstract

In this work, porous Zn/Cu composite hollow microspheres have been successfully prepared via a template-free solution phase route. By controlling the reaction temperature, porous Zn/Cu composite hollow microspheres with the different Zn/Cu mass ratios were achieved. The results from X-ray powder diffraction and X-ray photoelectron spectroscopy show that porous Zn/Cu composite hollow microspheres are Zn/Cu composite but not Zn/Cu alloy, and the composition of the oxide layers is mainly Cu2O phase. Scanning electron microscopic studies indicate that the metallic zinc powder microspheres consist of numerous small particles with an average diameter of about 100 nm, while the composite hollow microspheres are assembled by Zn/Cu composite submicrometer particles with an average diameter of about 500–700 nm. On the basis of these experimental results, a rational formation mechanism is proposed here.