Hydrogen Evolution Reaction on Nanocrystalline Co-Mo/Ni Composite-Coated Electrodes

Abstract

The electrochemical behaviours of the hydrogen evolution reaction(HER) at electrodes prepared by composite coating of nanocrytstalline Co-Mo alloy particles formed by ball milling on nickel base has been sludied by using sleady-state polarization and ac impedance techiu ques.The microstructure and the size of the nanocrystals of Co- Mo alloy and the morphology of the composite-coating surface of the electrodes are measured by XRD, TEM and SEM. Results show that the nanocrystalline Co-Mo alloys prepared by high energy ball milling has high electrocatalytic activity for HER. The electrocatalytic activity for the HER is enhanced and the energy of activation for HER is decreased with increasing milling time. They are attributed to the increase in the real surface areas of the electrode and high proportion of active atoms on the surface of electrodes. The temperature study show that the energy of activation of electrodesorption is the same as the energy of activation of the overall reaction. The reaction rate of HER on the electrodes is proved to be controlled by electrodesorption.