Formation of carbon nanotubes from mixture film of carbon and titanium

It was shown that a carbon nanotube was selectively formed from carbon film containing Ti, supported by a standard Mo transmission electron microscopic grid, by heating at 800 °C in vacuum. With heating above 950 °C, graphite and rutile crystals of TiO2 predominately appeared. The formation of oxide is due to the supply of oxygen from the Mo grid. The formation mechanism of the carbon nanotubes was discussed on the basis of the heat of combustion due to the oxidation of titanium. The present result will lead to the development of an efficient method of production of carbon nanotubes.