Synergistic CoCO3/MnCO3/TiOx composite over nickel foam as anode for alkaline seawater electrolysis

The creation of chloride-resistant electrocatalysts for seawater electrolysis presents significant challenges due to the competing chlorine evolution reaction (CER), which results in considerable anodic corrosion. In this study, a CoCO 3 /MnCO 3 /TiO x composite is developed on nickel foam (C 2 M 1 T x /NF) using a solvothermal approach. Structural analyses confirm the presence of both CoCO 3 and MnCO 3 phases, which together form a microspherical structure that offers numerous accessible active sites and promotes favourable adsorption–desorption kinetics. The addition of TiO x improves hydroxide adsorption and enhances structural stability. Electrochemical studies on alkaline seawater electrolysis (ASE) indicate that C 2 M 1 T 0.1 /NF serves as an effective anode by facilitating the oxygen evolution reaction (OER) significantly below the onset potential for CER. The catalyst reaches a current density of 50 mA·cm −2 at an overpotential of 415 mV. Additionally, during overall water splitting at 1.92 V, the system exhibits stable performance for 100 h while sustaining a current density of 20 mA·cm −2 . The improved performance is attributed to the synergistic Co–Mn redox coupling, structural and electronic modulation induced by Ti, and reduced chloro-oxidation due to CO 3 2− species at the electrode–electrolyte interface, which enables selective and long-lasting ASE.