GROWTH AND STRUCTURE OF SnO/ZnO BIAXIAL NANOWIRES ON ZnO NANOWIRE BY VAPOR-LIQUID-SOLID MECHANISM

Abstract

In this work, the biaxial SnO/ZnO nanowires in the average length of 5 μm, have been successfully synthesized on a ZnO-nanowire substrate using a chemical vapor deposition (CVD) system through a two-step process. First, ZnO nanowires were grown directly on the glass substrate with a gold catalyst. Then, these nanowires were used as templates for the growth of biaxial SnO/ZnO nanowires without any catalyst. The obtained products were characterized by X-ray diffraction (XRD), field-emission electron scanning microscopy (FE-SEM), and high-resolution transmission electron microscopy (HR-TEM). The Sn-Zn alloy formulated during the process was believed a catalyst for the growth of the biaxial SnO/ZnO nanowires. The biaxial structure was formed due to simultaneous growth of SnO and ZnO nanowire along the direction of SnO [110] and ZnO [002], respectively. A possible growth mechanism of the biaxial SnO/ZnO nanowire was discussed based on the vapor-liquid-solid (VLS) mechanism. The as-synthesized structure could be a good candidate for nano-sensors.