Gold nanocluster-enhanced electrochemical activity of a phosphorus-doped tetrahedral amorphous carbon film

An electrochemical electrode of a phosphorus-doped tetrahedral amorphous carbon film modified with gold nanoclusters (Au/ta-C:P) was prepared by electrodepositing gold nanoclusters on the surface of ta-C:P film synthesized by filtered cathodic vacuum arc technology. The microstructure, surface morphology and electrochemical behavior of ta-C:P and Au/ta-C:P films were characterized by X-ray photoelectron spectroscopy, Raman spectroscopy, scanning electron microscopy and electrochemical voltammetry. Results indicated that a pulse bias of -80V was favorable for doping phosphorus into the carbon network to improve the electrical conduction and electrochemical activity of the film. Furthermore, gold nanoclusters increased the effective surface area of the ta-C:P electrode, enhanced the activity and reversibility towards the ferricyanide oxidation reaction and improved the activity for the catalytic oxidation of dopamine. All of these revealed the potential applications of ta-C:P and Au/ta-C:P films in electroanalysis and biosensors.