Chelating N-Heterocyclic Carbene Ligands Enable Tuning of Electrocatalytic CO2 Reduction to Formate and Carbon Monoxide: Surface Organometallic Chemistry

Zhi Cao; Jeffrey S Derrick; Jun Xu; Rui Gao; Ming Gong; Eva M Nichols; Peter T Smith; Xingwu Liu; Xiaodong Wen; Christophe Copéret; Christopher J Chang

doi:10.1002/anie.201800367

Chelating N-Heterocyclic Carbene Ligands Enable Tuning of Electrocatalytic CO₂ Reduction to Formate and Carbon Monoxide: Surface Organometallic Chemistry

Angew Chem Int Ed Engl. 2018 Apr 23;57(18):4981-4985. doi: 10.1002/anie.201800367. Epub 2018 Mar 23.

Authors

Zhi Cao¹, Jeffrey S Derrick^{1

2}, Jun Xu³, Rui Gao^{4

5}, Ming Gong^{1

2}, Eva M Nichols^{1

2}, Peter T Smith^{1

2}, Xingwu Liu^{4

5}, Xiaodong Wen^{4

5}, Christophe Copéret³, Christopher J Chang^{1

6

2}

Affiliations

¹ Department of Chemistry, University of California, Berkeley, CA, 94720, USA.
² Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA.
³ Department of Chemistry and Applied Biosciences, ETH Zürich, Vladimir Prelog Weg 1-5, 8093, Zürich, Switzerland.
⁴ Institute of Coal Chemistry, Chinese Academy of Sciences, Taiyuan, Shanxi, 030001, China.
⁵ Synfuels China, Beijing, 100195, China.
⁶ Department of Molecular and Cell Biology, Howard Hughes Medical Institute, University of California, Berkeley, CA, 94720, USA.

PMID: 29498168
DOI: 10.1002/anie.201800367

Abstract

Reported here is the chelate effect as a design principle for tuning heterogeneous catalysts for electrochemical CO₂ reduction. Palladium functionalized with a chelating tris-N-heterocyclic carbene (NHC) ligand (Pd-timtmb^Me ) exhibits a 32-fold increase in activity for electrochemical reduction of CO₂ to C1 products with high Faradaic efficiency (FE_C1 =86 %) compared to the parent unfunctionalized Pd foil (FE=23 %), and with sustained activity relative to a monodentate NHC-ligated Pd electrode (Pd-mimtmb^Me ). The results highlight the contributions of the chelate effect for tailoring and maintaining reactivity at molecular-materials interfaces enabled by surface organometallic chemistry.

Keywords: CO2 reduction; N-heterocyclic carbenes; electrocatalysis; palladium; surface chemistry.

Publication types

Research Support, Non-U.S. Gov't