Web Release Date: December 28,
Controllable Fabrication and Photocatalytic Activity of ZnO Nanobelt Arrays


and

Carbon Research Laboratory, State Key Laboratory of Fine Chemicals, Center for Nano Materials and Science, School of Chemical Engineering, Dalian University of Technology, 158 Zhongshan Road, P.O. Box 49, Dalian 116012, China, and Key Laboratory for Micro/Nano Technology and System of Liaoning Province, Dalian University of Technology, Dalian 116023, China
Received: October 16, 2007
Abstract:
Well-aligned single-crystalline ZnO nanobelt arrays were fabricated on a Si wafer by a carbothermal reduction route with the assistance of a SnO2/Sn species. The as-prepared ZnO nanobelt arrays were characterized by X-ray diffraction, scanning electron microscopy, energy dispersive X-ray spectroscopy, transmission electron microscopy, UV-vis spectroscopy, and photoluminescence spectroscopy. The photocatalytic activity for methyl orange on the ZnO nanobelt arrays was also investigated under UV irradiation. The ZnO nanobelts are several tens of nanometers in thickness, 100-500 nm in width, and have a length of up to several micrometers. It has been found that the ZnO nanobelt arrays form on a substrate only when the thickness of the SnO2 coating is less than 100 nm. The rod-/comb-like ZnO nanostructures and the ZnO film can be obtained by increasing the SnO2 loading or the temperature, respectively. The ZnO nanobelts grow from the active surface at the nanobelt root via a vapor-liquid-solid mechanism. The ZnO nanobelt arrays show strong emission both in the UV and in the green region. The as-prepared ZnO nanobelt arrays have a good photocatalytic property, as evidenced by the result that over 94% of the methyl orange decomposed over the ZnO nanobelt arrays, which is better than the as-prepared ZnO film and the rod-/comb-like ZnO nanostructures under identical conditions.
Download the full text: PDF | HTML