Preparation and Electrocatalytic Performance for Hydrogen Evolution Reaction of the Ni/LaNi5 Porous Composite Electrode

At first, the Ni-Zn coating was electroplated, then, the coating was immersed in concentrated alkali solution to remove zinc and the porous nickel was obtained. Finally, the Ni/LaNi5 porous composite electrode was prepared on this porous nickel surface by means of the composite electro-deposition. The electro-catalytic properties for hydrogen evolution reaction of the electrode were evaluated by electrochemical steady-state polarization curve and electrochemical impendence spectroscopy (EIS). And the stability of the electrode was studied by open circuit potential and constant potential electrolysis technology for long time and discontinuity electrolysis. Results show that the apparent exchange current density of the porous composite electrode is 172 and 26 times as much as that of the nickel electrode and the porous nickel electrode, respectively. Because LaNi5 possesses the effect of electrode protection, the stability of the porous composite electrode is better than that of the porous nickel.