Controlled growth of ZnO/SnO2 mixed nanowires by carbon assisted thermal evaporation process

Abstract

This work reports the controlled growth of ZnO/SnO2 mixed nanowires, fabricated by the bottom up process of carbon assisted thermal evaporation method, through vapor-liquid-solid (VLS) mechanism. In this study, SnO2, ZnO and activated carbon powders are used to grow ZnO/SnO2 mixed nanowires with the help of a gold catalyst on alumina substrate. Tin, zinc, and gold eutectic compounds promote a nucleation site for the deposition of ZnO/SnO2 mixed nanowires synthesized at 900°C. The crystalline structures of ZnO/SnO2 nanowires are analyzed by X-ray diffraction (XRD). The morphological characterization of fabricated products is performed by field emission scanning electron microscopy (FESEM). A sharp peak of XRD patterns exhibits the high crystallinity of the ZnO/SnO2 mixed nanowires. FESEM images show that the length of nanowires increased from 2 μm to 80 μm with the increase of growth time from 30 min to 120 min. These mixed nanowires could find potential applications in chemical gas sensors and optoelectronic devices.