The electrocatalytic behaviour of electroless Ni–P alloys

Electroless nickel–phosphorous coated carbon steel electrodes, with P content ranging from 4.0 to 13.8 at.% P, were prepared and employed to investigate the effect of the structural and morphological features on the alloy electrocatalytic activity. Subsequent heat (400 °C, 1 h) or electrochemical (anodizing at 0.5 V followed by multi-cycle polarization) treatments were performed and the so imparted modifications established. The deposits characterization by glazing X-ray diffraction and by atomic force microscopy provided information on the conditions for the formation of crystallites in amorphous films and its influence on the surface topography; the comparative analysis of the cyclic voltammetry data gave information on the importance of the P content in nickel hydroxides/oxides formation. The possibility of using the as-deposited or the treated electroless Ni–P coatings as cathodes, in alkaline media, was evaluated with the study of the hydrogen evolution reaction.