Pt-Modified CoFe Alloy Electrode Enables Ampere-Level Coproduction of Acetate and Hydrogen

Abstract

Abstract Paired electrolysis integrating the ethanol oxidation reaction (EOR) with the hydrogen evolution reaction (HER) provides an energy-efficient strategy for the simultaneous production of value-added chemicals and green hydrogen. Herein, we report a Pt-modified CoFe alloy electrode directly grown on nickel foam (Pt-CoFe/NF) through a facile two-step strategy. The conductive CoFe alloy maximizes Pt utilization, while the electronically coupled Pt-CoFe interface regulates the electronic structure, accelerates charge transfer, and generates abundant catalytic active sites. Operando spectroscopic investigations, together with density functional theory calculations reveal that the Pt-CoFe heterointerface promotes water activation and *OH generation for ethanol oxidation, while simultaneously optimizing *H adsorption for hydrogen evolution, thereby synergistically accelerating both half-reactions. As a result, the Pt-CoFe/NF electrode requires only 1.48 V and 95.8 mV to achieve 1000 mA cm–2 for the EOR and HER, respectively, and also delivers a high acetate Faradaic efficiency (90.6%) with a yield rate of 4.30 mmol h–1 cm–2 at 1.9 V. In addition, the assembled EOR‖HER electrolyzer delivers a low cell voltage of 2.25 V to reach 1 A cm–2, high yields of H2/acetate and realizes long-term stability for 100 h.