Multi-component materials are a new trend in catalyst development for electrochemical CO 2 reduction. Understanding and managing the chemical interactions within a complex catalyst structure may unlock new or improved reactivity, but is scientifically challenging. We report the first example of capping ligand-dependent metal–oxide interactions in Au/SnO 2 structures for electrocatalytic CO 2 reduction. Cetyltrimethylammonium bromide capping on the Au nanoparticles enables bifunctional CO 2 reduction where CO is produced at more positive potentials and HCOO − at more negative potentials. With citrate capping or no capping, the Au–SnO 2 interactions steer the selectivity toward H 2 evolution at all potentials. Using electrochemical CO oxidation as a probe reaction, we further confirm that the metal–oxide interactions are strongly influenced by the capping ligand.
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Hydrogenation and electrocatalytic reduction of carbon dioxide to formate with a single Co catalyst
A cobalt( i ) complex is shown to be capable of both electrocatalytic reduction and hydrogenation of CO 2 to formate. Several proposed intermediates are characterized and thus form the basis for a proposed mechanism that allows for the dual reactivity: reduction of CO 2 via H 2 addition, and H + /e − equivalents. The work makes use of a novel tris(phosphino) ligand. When a pendent amine is attached to the ligand, no change in catalytic reactivity is observed.
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- Award ID(s):
- 1945646
- PAR ID:
- 10219144
- Date Published:
- Journal Name:
- Chemical Communications
- Volume:
- 56
- Issue:
- 81
- ISSN:
- 1359-7345
- Page Range / eLocation ID:
- 12142 to 12145
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/d0cc04310a
