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The subject of this work is Ni50Mo40Ti10 alloy produced by mechanical alloying and subsequent heat treatment. The obtained material was tested as electrode for the hydrogen evolution reaction (HER) in an alkaline environment. The results were compared with those obtained for the Ni50Mo50 catalyst. Electrochemical characterization was carried out by the steady‐state polarization method and the electrochemical impedance spectroscopy (EIS). On the basis of the results of the EIS measurements, the average rate constant of the HER was determined. The calculated values of surface roughness factor, Rf, allowed to evaluate the true catalytic effect of the investigated electrode material. It was stated that Ni50Mo40Ti10 alloy annealed at 1173 K exhibits the higher electrocatalytic activity for the HER compared with the Ni50Mo50. The increase in the intrinsic activity could be attributed to the presence of NiMo intermetallic phase and Ni(Ti) solid solution. Copyright © 2014 John Wiley & Sons, Ltd.

Composite Ni + Mo coatings were obtained by electrodeposition of Ni with Mo particles on a steel substrate from the nickel bath in which metallic Mo powder was suspended by stirring. Deposits were characterized by the presence of Mo particles embedded into the crystalline nickel matrix. Incorporation of metallic powder into electrolytic nickel matrix causes an increase in the real surface area of deposits.The composite coatings obtained were tested as electrode materials for hydrogen evolution reaction (HER) in an alkaline environment. Electrochemical characterization of the composites was carried out by steady-state polarization method and electrochemical impedance spectroscopy (EIS) measurements. It was ascertained, that Ni + Mo coatings are characterized by enhanced electrochemical activity for this process, which was confirmed by considerable decrease in the hydrogen evolution overpotential at the current density of 100 mA cm −2 − η 100 , by a nearly 170-260 mV compared to nickel electrode. Exchange current density j 0 increases with the increase in Mo content in the coatings.Based on the results of EIS measurements, the rate constants of the HER for Ni and Ni + 44%Mo coatings were determined. The calculated values of surface roughness factor R f allowed also to evaluate the influence of the real surface area on the electrocatalytic performance of these materials in an alkaline environment. It was stated that the improvement of the electrocatalytic performance of Ni + Mo composite coatings could be attributed to the increase in their real surface area as well as to the synergetic effect of molybdenum with the nickel matrix, as Ni/Mo materials are considered in literature, typical electrocatalysts for the HER.