Coordination Polymer Electrocatalysts Enable Efficient CO-to-Acetate Conversion

Upgrading carbon dioxide/monoxide to multi-carbon C2+ products using renewable electricity offers one route to more sustainable fuel and chemical production. One of the most appealing products is acetate, the profitable electrosynthesis of which demands a catalyst with higher efficiency. Here, a coordination polymer (CP) catalyst is reported that consists of Cu(I) and benzimidazole units linked via Cu(I)-imidazole coordination bonds, which enables selective reduction of CO to acetate with a 61% Faradaic efficiency at -0.59 volts versus the reversible hydrogen electrode at a current density of 400 mA cm(-2) in flow cells. The catalyst is integrated in a cation exchange membrane-based membrane electrode assembly that enables stable acetate electrosynthesis for 190 h, while achieving direct collection of concentrated acetate (3.3 molar) from the cathodic liquid stream, an average single-pass utilization of 50% toward CO-to-acetate conversion, and an average acetate full-cell energy efficiency of 15% at a current density of 250 mA cm(-2).

Automated summary

Upgrading carbon dioxide/monoxide to multi-carbon C2+ products using renewable electricity offers a sustainable approach to fuel and chemical production. A new coordination polymer catalyst consisting of Cu(I) and benzimidazole units linked via Cu(I)-imidazole coordination bonds enables selective reduction of CO to acetate with a 61% Faradaic efficiency. The catalyst integrated in a cation exchange membrane-based membrane electrode assembly allows stable acetate electrosynthesis and achieves concentrated acetate collection, high CO-to-acetate conversion efficiency, and good acetate full-cell energy efficiency.