Growth of vertically aligned carbon nanotubes by CVD by evaporation of carbon precursors

Abstract

We report about the growth of carbon nanotubes, carbon microfibers and other forms of carbon on uncoated silicon and glass substrates, obtained by evaporating either a solid carbon precursor such as camphor or a liquid one such as cyclohexanol. The latter is a cyclic alcohol never used before in this field. The process of synthesis involves the coevaporation of the carbon precursor and ferrocene, used as the catalyst source, in nitrogen atmosphere. The morphology and structure of the samples grown at various substrate temperatures were characterized by Raman and FT-IR spectroscopy, HR-TEM and SEM analysis. At a substrate temperature of about 650 °C a ‘carpet’ of vertically oriented nanotubes, with spare signs of other form of carbons, is obtained on silicon substrate, whereas a disordered carbon nanotubes structure and other carbon form are grown on glass substrates. The results demonstrate the ability of this method to grow carbon nanotubes on uncoated glass substrates.