NiP cathode catalyst for alkaline water electrolyser

Abstract

Hydrogen is considered a promising alternative energy source due to its high energy density and environmental benefits. Among the various hydrogen production methods, water electrolysis is the most effective way to obtain high-purity hydrogen. However, the efficiency of this process heavily depends on the catalyst used. Precious metals like Pt and Au exhibit excellent catalytic activity but are costly and scarce. Therefore, developing costeffective, conductive, and environmentally friendly catalysts is crucial for advancing hydrogen production technologies. This study focuses on designing a highly efficient hydrogen evolution reaction (HER) catalyst for alkaline electrolysis using a perforated stainless steel support. Initially, the support is coated with two layers of nickel film, followed by the electrodeposition of copper-zinc (CuZn) via the chronopotentiometry method. A selective zinc leaching process in an alkaline solution generates a highly porous structure. Finally, the electrode is doped with nickel-phosphorus (NiP) using an electroless coating technique. Characterization by XRD and SEM confirms the formation of amorphous NiP. Electrochemical analysis using EIS and LSV demonstrates that the NiPcoated electrode achieves the highest HER efficiency, with a current density of 100 mA cm-2 at-1.66 V and a Tafel slope of 133.8 mV dec-1 in 1.0 M KOH.