Electrochemical characterization of Raney nickel electrodes prepared by atmospheric plasma spraying for alkaline water electrolysis

The Ni–Al alloy-coated electrode, which was heat treated at 610°C in H2 atmosphere for 1h, showed more evenly distributed Al component on the surface. [Display omitted] •Raney Ni electrode was prepared by the atmospheric plasma spraying (APS) method.•The electrode showed great activity in HER compared to the polished Nickel.•H2 heat-treated Raney Ni electrode had no NiAl phase and a small Ni crystallite size.•Electrochemical properties for HER before and after H2 heat treatment were similar.•Low Al content of H2 heat-treated Raney Ni led to faster deactivation of electrode. A Raney Ni electrode was prepared by the simple and economical atmospheric plasma spraying method. It showed excellent performance for hydrogen evolution reaction (HER), as indicated by a Tafel slope of 54mV/dec and overvoltage of 108mV at 300mA/cm2. The Ni–Al alloy coating contained a NiAl phase, which has a very slow Al leaching rate in alkaline solution. H2 heat treatment of the electrode enhanced the uniformity of Al distribution in the coating and adhesion of the coating to the substrate. However, the HER performance did not improve and the electrode was rendered more structurally vulnerable to deactivation.