Effect of electrolytic oxidation upon the surface chemistry of type A carbon fibres: III. Chemical state, source and location of surface nitrogen Original Research Article

High energy resolution XPS and high mass resolution TOF SIMS have been used to probe the surface chemistry of type A carbon fibres. Four components have been identified within the XPS N1s envelope through a range of ammonium bicarbonate electrolytic oxidation levels. These peaks were assigned to amide, aza, imide and protonated amine functionalities. The amide is identified as the major nitrogen functionality introduced by electrolytic oxidation, and analysis of a model carbon (pyrolytic graphite) surface has shown the electrolyte to be the source. The distribution of the nitrogen and oxygen within the surface (5 nm) of the fibre is qualitatively determined using angle-resolved XPS. The implication upon possible adhesion mechanisms between fibre and epoxy resin are considered using this new information.