Deposition of nanocrystalline diamond and titanium oxide coatings onto pyrolytic carbon using CVD and sol-gel techniques

In this paper, we report the deposition of freestanding nanocrystalline diamond (NCD) films and dense nanocrystalline titanium oxide (nc-TiO2) coatings onto pyrolytic carbon (PyC) using advanced chemical vapour deposition (CVD) and sol-gel techniques, respectively. The micro-structural properties, such as surface morphology and crystallinity, of PyC, NCD and nc-TiO2 were characterised using XRD, Raman spectroscopy and SEM analysis. Freestanding NCD films were prepared using our newly introduced time-modulated CVD (TMCVD) process. Furthermore, conventional sol-gel technique was used to uniformly coat PyC with dense nc-TiO2 coatings. The as-grown nc-TiO2 coatings were found to display smooth surface profiles and the average crystallite size was in the range approximately 30-50 nm. (C) 2004 Elsevier B.V. All rights reserved.