Published online by Cambridge University Press: 10 February 2011
The electrochemical reaction of polycrystalline MoxN (x=1 or 2) thin film electrodes in 4.4 M H2SO4 electrolyte has been investigated. The films were prepared by a temperature programmed procedure involving the reaction of MoO3, and NH3 The electrochemical voltage stability of these films in the electrolyte, referenced to a standard hydrogen electrode (SHE), was + 0.70 V (-0.01 to + 0.69). Below + 0.69 V, cyclic voltammetry and AC impedance spectroscopy indicated that MoxN electrodes were capacitive. However, above this value an electrochemical reaction of the MoxN films was observed. The formation of an amorphous phase in the reacted MoxN films was indicated by X-ray diffraction (XRD) patterns. Secondary ion mass spectroscopy (SIMS) detected the presence of hydrogen, oxygen, and sulfur. The voltage bias (+ or -) applied to the electrodes influenced the chemical composition of the reacted MoxN films.