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-TiO 2) 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-TiO 2 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-TiO 2 coatings. The as-grown nc-TiO 2 coatings were found to display smooth surface profiles and the average crystallite size was in the range approximately 30–50 nm.