X-RAY PHOTOELECTRON SPECTROSCOPIC STUDIES OF CARBON-FIBER SURFACES VII-ELECTROCHEMICAL TREATMENT IN AMMONIUM SALT ELECTROLYTES

Carbon fibres, electrochemically treated in a variety of different ammonium salt electrolytes, have been analysed using X-ray photoelectron spectroscopy. Substantial surface oxidation is found in various ammonium salts, with the exception of ammonium bicarbonate, where low surface oxidation and carbon dioxide evolution occurs. Most of the surface functionality involves carbon-oxygen bonds, but some surface nitrogen is found and this can be greatly enhanced by saturating the electrolyte solution with ammonia gas.