Research Of Electrodeposited Diamond-like Carbon And Doped Carbon Films

In this paper, liquid phase electrodepositon technology was applied to prepare diamond-like carbon and doped diamond-like carbon films.With low deposition potential, diamond like carbon films were electrodeposited from acetonitrile and water solutions with different concentration of acetonitrile. The structure and tribological properties of the films were characterized and tested respectively. The films obtained from acetonitrile and water solution with different concentration have evident difference in structure and properties. With more water in the carbon source, the surface root mean square roughness is reduced, and the diameter of the grains of the films is reduced. The film obtained from the carbon source with 10% acetonitrile has compact and uniform surface morphology. However, the film deposited from the solution with 5% acetonitrile possesses inhomogeneous particles, owing to a low form nuclear density because of shack of positive carbon ions in the process of the electrodeposition. The Raman spectra indicate that the amount of sp3 carbon in the film increases with increasing water in the carbon source. The film prepared from the carbon source with 10% acetonitrile shows excellent friction-reducing and anti-wear property and relative low friction coefficient. The diamond like carbon film was able to forma a transfer film in the friction process, and it showed some signs of abrasive wear as well, indicating that the film could be dominated by mixed lubricating mechanisms.The fluorinated diamond like carbon film was prepared from CF3COOH as the carbon source. High potential applied between the two electrodes was found to lead to boiling of the carbon source near to the electrode, generating lots of small air bubbles in the deposition, and causing the surface roughness of the films. The surface energy was reduced by doping the fluorine into the diamond like carbon films. The films recorded contact angle of 150°. Low surface energy and special rough structure is imperative for preparing the surperhydrophobic surface.It is favourable to prepare doped diamond like carbon film by electrodeposition. The nickel doped diamond like carbon film was fabricated by electrodeposition from the mixture of DMSO and acetic nickel at a relatively low potential. The film was found to have nano-composite structure composed of metallic nickel inclusions in carbonaceous matrix, but nickel was partially oxidized by air. Raman spectroscopic analysis proves that there exists polyacetylene in nickel incorporated diamond like carbon film.