Cathodic Hydrogen Evolution on Nickel in Acidic Environment

Cathodic hydrogen evolution on polycrystalline nickel with differently prepared surfaces and on individual faces of single-crystal nickel is studied. It is established that the hydrogen overvoltage on nickel in acid media considerably depends on the surface preparation technique. In some cases, the difference in the hydrogen overvoltage cannot be explained by different roughness of electrodes. The absorption of atomic hydrogen in a surface layer may substantially alter electrocatalytic properties of both polycrystalline and single-crystal nickel.