NiOx–FeOx Nanoclusters Anchored on g-C3N4 Sheets for Selective Seawater Oxidation with High Corrosion Resistance

Nickel-iron oxides have been suggested to be an efficient and selective low-cost anode for seawater oxidation due to their unique orbital confinement and compatible electronic structure. However, their poor stability at high current density in corrosive seawater is the main bottleneck in the seawater electrolysis for H2 production. Herein, a g-C3N4-supported Ni–Fe oxide nanocluster (NiOx–FeOx@g-C3N4) as an efficient and durable anode for alkaline seawater oxidation is reported. The experimental findings demonstrate that the NiOx–FeOx@g-C3N4 anode is more anticorrosive than pristine NiOx–FeOx NCs. The synergistic effect of the heterostructure enhances the corrosion resistance, structural integrity, and accelerates the gas release ability, resulting in outstanding sustainability over 100 h of continuous electrolysis at high current density without noticeable degradation and hypochlorite formation.