Weak CO binding sites induced by Cu-Ag interfaces promote CO electroreduction to multi-carbon liquid products.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 36755022.
- Also identified by DOI 10.1038/s41467-023-36411-5 and PMC identifier 9908878.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
Electrochemical reduction of carbon monoxide to high-value multi-carbon (C<sub>2+</sub>) products offers an appealing route to store sustainable energy and make use of the chief greenhouse gas leading to climate change, i.e., CO<sub>2</sub>. Among potential products, C<sub>2+</sub> liquid products such as ethanol are of particular interest owing to their high energy density and industrial relevance. In this work, we demonstrate that Ag-modified oxide-derive Cu catalysts prepared via high-energy ball milling exhibit near 80% Faradaic efficiencies for C<sub>2+</sub> liquid products at commercially relevant current densities (>100 mA cm<sup>-2</sup>) in the CO electroreduction in a microfluidic flow cell. Such performance is retained in an over 100-hour electrolysis in a 100 cm<sup>2</sup> membrane electrode assembly (MEA) electrolyzer. A method based on surface-enhanced infrared absorption spectroscopy is developed to characterize the CO binding strength on the catalyst surface. The lower C and O affinities of the Cu-Ag interfacial sites in the prepared catalysts are proposed to be responsible for the enhanced selectivity for C<sub>2+</sub> oxygenates, which is the experimental verification of recent computational predictions.