Ce-doped cobalt-based hydroxide assisted with low-temperature molten salt for industrial oxygen evolution reaction

Developing low cost and high-performance oxygen evolution electrocatalysts is significant to improve the efficiency of water electrolysis for large-scale hydrogen production. Cobalt hydroxide is a promising electrocatalyst for oxygen evolution reaction (OER), but its poor conductivity and activity seriously restrict the practical application. A simple one-step low temperature molten salt method was applied to successfully synthesize the Ce-doped cobalt hydroxide nitrate (Ce-CoNH/CF), which exhibits outstanding OER performance with a low overpotential of 448 mV at the current density of 1000 mA/cm² in 1 mol/L KOH. The remarkable performance of Ce-CoNH/CF electrode in OER may be the comprehensive result of fast reaction kinetics, large electrochemical active specific surface area (ECSA) and small charge transfer resistance (Rct) as revealed by the Tafel, cyclic voltammetry (CV) and electrochemical impedance spectra (EIS) analysis. Under the simulated industrial test conditions (6 mol/L KOH, 70 ℃), the Ce-CoNH/CF electrode still displays excellent OER performance.