Fabrication of hollow ZnO microsphere with zinc powder precursor

A facile approach is reported for the preparation of hollow ZnO microspheres using Zn powders as raw materials. Firstly, Zn(OH)2 was precipitated on the surface of Zn powder to form core/shell structure in solution, and subsequent calcination these core/shell composite particles at 650 °C in air would lead to the formation of ZnO hollow spheres whose diameter were determined by the dimension of the used Zn powder. XRD, TEM, SAED, EDS and UV–vis were used to characterize the as-prepared samples. A formation mechanism is proposed to be a process following the formation of Zn/Zn(OH)2 core/shell particles, the decomposition of Zn(OH)2 shell to ZnO, and the sublimation and oxidation of Zn core.