Fabrication of SnO<sub>2</sub>/Zn<sub>2</sub>SnO<sub>4</sub>/ZnO Nanocables through Thermal Oxidation of Zn and Sn Mixture Powders

Abstract

We demonstrate the synthesis of a three-layer-coaxial SnO2/ZnSn2O4/ZnO core–shell nanocable heterostructures with diameters 80-150 nm via thermal oxidation of Zn and Sn mixture powders. The products are characterized by scanning electron microscopy (SEM), X-ray powder diffraction (XRD) and field emission transmission electron microscopy (TEM). The structural analysis shows the formation of ZnSnO4 in the interface region between the SnO2 core and ZnO shell, which is resulted from inter－diffusion of Sn and Zn ions during thermal evaporation. The selected area electron diffraction (SAED) pattern was composed of two series of overlapped polycrystalline rings attributed to SnO2 and Zn2SnO4, one set of hexahedron diffraction spots that can be indexed to the hexagonal ZnO. On the basis of investigation of the microstructures, the possible formation mechanism of Zn2SnO4 is discussed.