Artículo de revista
Electrocatalysis of the hydrogen evolution reaction by rhenium oxides electrodeposited by pulsed-current
Fecha
2015Registro en:
Electrochimica Acta 178 (2015) 739–747
DOI: 10.1016/j.electacta.2015.08.065
Autor
Vargas Uscategui, Alejandro
Mosquera, Edgar
Chornik Aberbuch, Boris
Cifuentes, Luis
Institución
Resumen
Rhenium oxides are materials of interest for applications in the catalysis of reactions such as those occurring in fuel cells and photoelectrochemical cells. This research work was devoted to the production of rhenium oxide by means of pulsed current electrodeposition for the electrocatalysis of the hydrogen evolution reaction (HER). Rhenium oxides were electrodeposited over a transparent conductive oxide substrate (Indium Tin-doped Oxide - ITO) in an alkaline aqueous electrolyte. The electrodeposition process allowed the production of rhenium oxides islands (200-600 nm) with the presence of three oxidized rhenium species: Re-IV associated to ReO2, Re-VI associated to ReO3 and Re-VII associated to H(ReO4) H2O. Electrodeposited rhenium oxides showed electrocatalytic behavior over the HER and an increase of one order of magnitude of the exchange current density was observed compared to the reaction taking place on the bare substrate. The electrocatalytic behavior varied with the morphology and relative abundance of oxidized rhenium species in the electrodeposits. Finally, two mechanisms of electrocatalysis were proposed to explain experimental results.