Highly active electrocatalytic alcohol oxidation coupled hydrogen production with unsaturated Ni-O(OH) coordination

Abstract Electrocatalytic H₂ production coupled with valuable chemical fabrication is highly desirable and sustainable approach for a carbon neutral future. The prerequisite for its industrialization on terawatt-scale is the exploitation of an electrocatalyst that can operate steadily at current densities exceeding ampere levels. In this work, a Ni-O(H)-C electrocatalyst is proposed to realize the exceptional performance at the ampere-level current densities towards ethanol electrooxidation to acetic acid (EOR), hydrogen evolution reaction (HER), and their integrated system. This catalyst achieves a current density of 2 A cm–² for EOR and 1.5 A cm–² for HER at approximately 320 mV overpotential. This remarkable activity is achieved by the unsaturated atomic confinement of Ni-O(OH) species on the surface layer of Ni crystal, which offers an optimized electronic structure to suppress the kinetic processes, and block unfavorable structural transformation during electrocatalysis. A Ni-O(H)-C catalytic HER||EOR integration system offers a 220 mV voltage reduction at 1 A cm–² in comparison to that of Pt/C||RuO₂ water electrolysis cell. A Zn-ethanol-air battery is equipped with a Ni-O(H)-C catalyst, exhibiting more than 500 h of stable operation. Thanks to extensive universality of the proposed alcohol systems, our findings shine a bright future for the efficient and scalable manufacture of the value-added chemicals, together with high-purity hydrogen production.