Characterization of Electrochemically Co-deposited Metal-Molybdenum Oxide Films

Molybdenum oxide films with and without metal inclusions were electrochemically deposited on glassy carbon electrodes and characterized by soft X-ray spectroscopy, X-ray diffraction, scanning electron microscopy, and Rutherford backscattering spectroscopy. The local coordination of Mo is preferentially octahedral, but changes in the composition promote the appearance of tetrahedral Mo sites. The Mo local structure configurations were evaluated when different potential cycles were used in the modification of the electrode surface. Some metals (Pt, Pd, Rh, and Cu) were co-deposited with the Mo species and their effect on the obtained material was investigated. Pt and Cu favored the formation of bronzes and the enrichment of the film with tetrahedral units of MoOx. The occupancy level of the 4d orbital of Mo was examined as an indicator of interactions between Mo and co-deposited metals.