Trifunctional layered electrodeposited nickel iron hydroxide electrocatalyst with enhanced performance towards the oxidation of water, urea and hydrazine

In recent years, low-cost, non-noble metal-based and stable catalysts have gained attention for the development of clean energy devices. Additionally, the synthesis of materials that can exhibit more than one electrocatalytic reaction is notable. In this work, stepwise electrodeposited nickel-iron hydroxide nanoarrays are investigated as anode electrocatalysts with enhanced performance towards the oxidation of water, urea, and hydrazine. The stepwise electrodeposited nickel-iron hydroxide (NiFe(OH)₂-SD/NF) electrodes show excellent electrocatalytic activity and stability for the oxygen evolution reaction (OER) with a low potential of 1.45 V (vs RHE) at a current density of 10 mA cm⁻². These electrodes further display excellent catalytic activity towards the urea oxidation reaction (UOR) and hydrazine oxidation reaction (HzOR) with potentials lower than 1.32 V (vs RHE) and 0.06 V (vs RHE), respectively. Owing to synergistic effects, a porous structure for mass transport leads to excellent electrocatalytic performance. This non-precious-metal nickel-iron hydroxide, prepared by a simple synthesis approach, is promising for hybrid water electrolysis applications and the development of environmentally friendly clean energy reactions.