Electrocatalytic activity of composite Fe/TiO2 electrodeposits for hydrogen evolution reaction in alkaline solutions
By Danilov, F. I.; Tsurkan, A. V.; Vasil'eva, E. A.; Protsenko, V. S.
Published in International Journal of Hydrogen Energy
2016
Abstract
Abstract Fe/TiO2 composite coatings were obtained by electrodeposition using a methanesulfonate plating bath containing colloidal TiO2 particles. Iron/titania electrodeposited composites exhibited enhanced electrocatalytic activity towards hydrogen and oxygen evolution reactions (HER and OER) in an alkaline solution. The electrocatalytic properties of Fe/TiO2 composites towards the {HER} were studied by means of voltammetry, electrochemical impedance spectroscopy and chronoamperometry methods. An increase in TiO2 content in iron matrix resulted in an increase in the electrocatalytic activity. The kinetic parameters were calculated on the basis of Tafel plots and {EIS} measurements and the possible mechanisms of the {HER} and {OER} were considered. The hydrogen evolution reaction on Fe/TiO2 electrodes obeyed Volmer-Heyrovsky mechanism. It was concluded that the increase in the rate of the {HER} and {OER} on Fe/TiO2 composite electrodes may be associated with the emergence of the redox couples on the electrode surface and the growth of the concentration of the surface active sites. The Fe/TiO2 electrocatalysts showed a good catalytic stability in the {HER} and {OER} in 1 M NaOH solution.