In this study, we developed a novel assembly technique for macroscopic one-dimensional metal oxide/CNT composites. An essential feature of the technique lies in the use of non-aqueous electrolyte in place of the usual aqueous electrolyte for electroplating, which ensures well-dispersed CNTs without surfactants. We successfully obtain unique metal oxide/CNT composite, in which CNTs are well aligned along the composite axis. Moreover, we can control the length and diameter of the composite by adjusting withdrawal time and electroplating current level, respectively. In the fabrication, it was observed that the electroplating process endows the composite with extraordinary properties. The “seed” formed on an anode electrode pulls up a cylindrical ingot in a way similar to the Czochralski crystal growth during the pulling. The seed also enhances adhesion between the anode and the composite. Current-induced thermal excitation could cure defective CNTs, leading to recovery of the crystallinity. The electroplated tungsten oxide on CNT wall could play the role of an electron acceptor. These factors are believed to have contributed to the improvement in the conductivity of the composite. We expect that the crystal-like growth of metal oxide/CNT composite would become a valuable tool for fabrication of nanocomposites with improved characteristics.
Journal: TechConnect Briefs
Volume: 2, Nanotechnology 2010: Electronics, Devices, Fabrication, MEMS, Fluidics and Computational
Published: June 21, 2010
Pages: 157 - 160
Industry sector: Advanced Materials & Manufacturing
Topics: Advanced Materials for Engineering Applications