Electrochemical Synthesis of Ni-SnO2 Composite Electrodes for Hydrogen Evolution Reaction in Alkaline Solution

In this work, high efficient Ni-SnO 2 electrodes were prepared for the alkaline hydrogen evolution reaction (HER) by a simple composite electroplating method from sulphamate bath containing SnO 2 nano-particles. The Ni-SnO 2 electrode was physically characterized byscanning electron microscopy (SEM), energy dispersive analysis of X-ray (EDAX),and X-ray diffraction (XRD). These physical characterization results revealed that the homemade SnO 2 particles (about 170 nm) were successfully co-deposited in coatings. The composited SnO 2 changed the surface morphology and phase structure of Ni matrix. The electrochemical activities and stabilities for HER weremonitored bysteady-state polarization, Tafel plots, electrochemical impedance spectroscopy (EIS) and chronopotentiometry technique. The activity was confirmed via the quantification of H 2 gases that evolved during chronopotentiometry study. The Ni-SnO 2 showed a higher catalytic activity for H 2 evolution, compared with Ni. The OH ads on SnO 2 surface was benefit to the formation of adsorbed H ads which is the rate-determining step for HER.