ZnO Nanostructures in Vapor Transport Growth Method

In this paper, vapor transport method was explored for controlling the size and morphology of ZnO nanostructures. A mixture of commercially available ZnO and carbon (C) powders were used as starting raw materials. Carbon powder was used to reduce the growth temperature of ZnO nano/microstructures. The growth process was carried out in a quartz tube at 1100 C using argon and oxygen as carrier gases. By varying the ZnO/C weight ratio the size of the grown nanostructures was found to be reduced. The synthesized nanostructures were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM) and UV-vis spectroscopy. The morphology of the grown ZnO nano/microstrucutres depends upon the temperature zone of the tubular furnace. The photocatalytic activity of ZnO nanostructures of various morphologies were studied by the degradation of Resazurin under UV light. The thinner ZnO nanostructures show high photocatalytic activity. The increased photocatalytic activity of thinner nanostructures is attributed to higher surface activity of the nanowires.