Methanol upgrading coupled with hydrogen product at large current density promoted by strong interfacial interactions

Abstract

Anodic organic upgrading offers a promising strategy to produce value-added chemicals and to facilitate coupled hydrogen production but it is still challenging in terms of long-term stability and high activity of the electrocatalysts at large current densities. Herein, highly dispersed FeNi oxide heterojunctions anchored on nickel foam (Fe₂O₃/NiO) as efficient catalysts are synthesized via an ultrafast solution combustion strategy. In methanol electrooxidation, a large absolute current density (500 mA cm⁻² at 1.654 V vs. RHE) with a high faradaic efficiency (>98%) is achieved. In situ infrared spectroscopy and theoretical calculations indicate that the heterostructure modulates the electronic state of NiO through strong electronic interactions, providing unique collaborative active sites for the favorable dynamic conversion of methanol to formate and inhibiting further oxidation. Furthermore, the interface confinement effect also stabilizes the metastable nickel active site, which ensures the stability of the catalyst structure during the reversible redox cycling, resulting in a steady and dynamically-enhanced catalytic process.