The effect of tin ingredients on electrocatalytic activity of Raney-Ni prepared by mechanical alloying

Sn was added to the conventional Raney-Ni precursor powder by the mechanical alloying in order to improve the catalytic activity for hydrogen evolution reaction (HER). After leaching Al, the cathodic performance of the modified powder was investigated in 1 M NaOH at 303 K. Sn was incorporated in the Raney-Ni precursor alloy after mechanical alloying. This was confirmed by differential thermal analysis (DTA) and energy-dispersive X-ray spectroscopy (EDX). However, the appearance of a new phase due to the mechanical alloying was not observed by X-ray diffraction analysis (XRD). The Sn-containing Raney-Ni cathode indicated a decrease of the hydrogen overvoltage. This is because the Tafel slope of the Sn-containing Raney-Ni cathode decreases from 180 to 95 mV/decade. The Raney-Ni cathode prepared by electrochemical codeposition could increase the electrocatalytic activity when the mechanical alloyed powder substitutes for the conventional Raney-Ni precursor powder.