Direct formation of copper nanoparticles from atoms at graphitic step edges lowers overpotential and improves selectivity of electrocatalytic CO2 reduction

Burwell, Tom; Thangamuthu, Madasamy; Aliev, Gazi N.; Ghaderzadeh, Sadegh; Kohlrausch, Emerson C.; Chen, Yifan; Theis, Wolfgang; Norman, Luke T.; Alves Fernandes, Jesum; Besley, Elena; Licence, Pete; Khlobystov, Andrei N.

Abstract

A key strategy for minimizing our reliance on precious metals is to increase the fraction of surface atoms and improve the metal-support interface. In this work, we employ a solvent/ligand/counterion-free method to deposit copper in the atomic form directly onto a nanotextured surface of graphitized carbon nanofibers (GNFs). Our results demonstrate that under these conditions, copper atoms coalesce into nanoparticles securely anchored to the graphitic step edges, limiting their growth to 2–5 nm. The resultant hybrid Cu/GNF material displays high selectivity in the CO2 reduction reaction (CO2RR) for formate production with a faradaic efficiency of ~94% at -0.38 V vs RHE and a high turnover frequency of 2.78 × 106 h-1. The Cu nanoparticles adhered to the graphitic step edges significantly enhance electron transfer to CO2. Long-term CO2RR tests coupled with atomic-scale elucidation of changes in Cu/GNF reveal nanoparticles coarsening, and a simultaneous increase in the fraction of single Cu atoms. These changes in the catalyst structure make the onset of the CO2 reduction potential more negative, leading to less formate production at -0.38 V vs RHE, correlating with a less efficient competition of CO2 with H2O for adsorption on single Cu atoms on the graphitic surfaces, revealed by density functional theory calculations.

Citation

Burwell, T., Thangamuthu, M., Aliev, G. N., Ghaderzadeh, S., Kohlrausch, E. C., Chen, Y., Theis, W., Norman, L. T., Alves Fernandes, J., Besley, E., Licence, P., & Khlobystov, A. N. (2024). Direct formation of copper nanoparticles from atoms at graphitic step edges lowers overpotential and improves selectivity of electrocatalytic CO2 reduction. Communications Chemistry, 7(1), Article 140. https://doi.org/10.1038/s42004-024-01218-y

• Journal Article Type: Article
• Acceptance Date: Jun 5, 2024
• Online Publication Date: Jun 20, 2024
• Publication Date: Jun 20, 2024
• Deposit Date: Jun 22, 2024
• Publicly Available Date: Jun 25, 2024
• Journal: Communications Chemistry
• Print ISSN: 2399-3669
• Electronic ISSN: 2399-3669
• Publisher: Nature Research
• Peer Reviewed: Peer Reviewed
• Volume: 7
• Issue: 1
• Article Number: 140
• DOI: https://doi.org/10.1038/s42004-024-01218-y
• Public URL: https://nottingham-repository.worktribe.com/output/36304205
• Publisher URL: https://www.nature.com/articles/s42004-024-01218-y
• Additional Information: Received: 24 January 2024; Accepted: 5 June 2024; First Online: 20 June 2024; : The authors declare no competing interests.