Preparation of Carbon Nanotubes and Nanowires by Electrolysis in Molten Salts

Carbon nanotubes and metal nanowires were formed in situ during the electrolysis of graphite cathode using LiCl, LiOHand LiCl/SnCl2 melts as electrolyte, respectively. The structure and morphology were characterized by TEM, XRD and EDS analyses. TEM images showed that the prepared materials varied with the nature and composition of the melts. Carbon nanotubes were formed electrolytically in the LiCl melt with the diameters in the range of 75~100 nm, but β-Sn-filled carbon nanotubes were generated in molten LiCl+1.0%SnCl2 mixtures. Followed by subsequent oxidation in the air, β-Sn nanowires were converted into SnO2 in carbon nanotubes, which was identified by XRD analysis. The obtained SnO2 nanowires were of tetragonal structure ranging from 20~50 nm in diameter. It was implied that the occurrence of LiC6produced from cathodic reactions had significant influence on the formation of carbon nanostructure during electrolysis.