UCL Discovery
UCL home » Library Services » Electronic resources » UCL Discovery

Mechanistic insights into carbon–carbon coupling on NiAu and PdAu single-atom alloys

Kress, P; Réocreux, R; Hannagan, R; Thuening, T; Boscoboinik, JA; Stamatakis, M; Sykes, ECH; (2021) Mechanistic insights into carbon–carbon coupling on NiAu and PdAu single-atom alloys. The Journal of Chemical Physics , 154 (20) , Article 204701. 10.1063/5.0048977. Green open access

[thumbnail of NiAu_C-C_Coupling_Manuscript_SI.pdf]
Preview
Text
NiAu_C-C_Coupling_Manuscript_SI.pdf - Accepted version

Download (1MB) | Preview

Abstract

Carbon–carbon coupling is an important step in many catalytic reactions, and performing sp³–sp³ carbon–carbon coupling heterogeneously is particularly challenging. It has been reported that PdAu single-atom alloy (SAA) model catalytic surfaces are able to selectively couple methyl groups, producing ethane from methyl iodide. Herein, we extend this study to NiAu SAAs and find that Ni atoms in Au are active for C–I cleavage and selective sp³–sp³ carbon–carbon coupling to produce ethane. Furthermore, we perform ab initio kinetic Monte Carlo simulations that include the effect of the iodine atom, which was previously considered a bystander species. We find that model NiAu surfaces exhibit a similar chemistry to PdAu, but the reason for the similarity is due to the role the iodine atoms play in terms of blocking the Ni atom active sites. Specifically, on NiAu SAAs, the iodine atoms outcompete the methyl groups for occupancy of the Ni sites leaving the Me groups on Au, while on PdAu SAAs, the binding strengths of methyl groups and iodine atoms at the Pd atom active site are more similar. These simulations shed light on the mechanism of this important sp3–sp3 carbon–carbon coupling chemistry on SAAs. Furthermore, we discuss the effect of the iodine atoms on the reaction energetics and make an analogy between the effect of iodine as an active site blocker on this model heterogeneous catalyst and homogeneous catalysts in which ligands must detach in order for the active site to be accessed by the reactants.

Type: Article
Title: Mechanistic insights into carbon–carbon coupling on NiAu and PdAu single-atom alloys
Open access status: An open access version is available from UCL Discovery
DOI: 10.1063/5.0048977
Publisher version: https://doi.org/10.1063/5.0048977
Language: English
Additional information: This version is the author accepted manuscript. For information on re-use, please refer to the publisher’s terms and conditions.
UCL classification: UCL
UCL > Provost and Vice Provost Offices > UCL BEAMS
UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Engineering Science
UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Engineering Science > Dept of Chemical Engineering
URI: https://discovery.ucl.ac.uk/id/eprint/10128523
Downloads since deposit
73Downloads
Download activity - last month
Download activity - last 12 months
Downloads by country - last 12 months

Archive Staff Only

View Item View Item