Ligand-modified nanoparticle surfaces influence CO electroreduction selectivity.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 38582773.
- Also identified by DOI 10.1038/s41467-024-47319-z and PMC identifier 10998913.
- 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
Improving the kinetics and selectivity of CO<sub>2</sub>/CO electroreduction to valuable multi-carbon products is a challenge for science and is a requirement for practical relevance. Here we develop a thiol-modified surface ligand strategy that promotes electrochemical CO-to-acetate. We explore a picture wherein nucleophilic interaction between the lone pairs of sulfur and the empty orbitals of reaction intermediates contributes to making the acetate pathway more energetically accessible. Density functional theory calculations and Raman spectroscopy suggest a mechanism where the nucleophilic interaction increases the sp<sup>2</sup> hybridization of CO<sub>(ad)</sub>, facilitating the rate-determining step, CO* to (CHO)*. We find that the ligands stabilize the (HOOC-CH<sub>2</sub>)* intermediate, a key intermediate in the acetate pathway. In-situ Raman spectroscopy shows shifts in C-O, Cu-C, and C-S vibrational frequencies that agree with a picture of surface ligand-intermediate interactions. A Faradaic efficiency of 70% is obtained on optimized thiol-capped Cu catalysts, with onset potentials 100 mV lower than in the case of reference Cu catalysts.