Introduction
Hydrogen intercalation in intermetallics produces interesting modifications of the magnetic properties. In this field hydrogenation is often performed by gas phase reaction which foreseen the exposure of the intermetallic to high hydrogen pressure and high temperature [1-3] .
Hydrogen absorption in intermetallics is also regarded with great interest owing to the possibility to store weakly bonded hydrogen atoms ready to react with hydroxyl ions when they constitute the negative electrode of a battery, typically in Ni/IMCH battery.
In this work GdCo2 hydriding has been carried out electrochemically in concentrated KOH aqueous solution with the aim to optimise this procedure which offers many advantages in comparison with the gas phase reaction method. GdCo2 has been chosen for the availability of the experimental magnetic data of this phase and its hydrides GdCo2Hx.[4].