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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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Distinguishing the mechanism of electrochemical carboxylation in CO 2 eXpanded Electrolytes
We shed light on the mechanism and rate-determining steps of the electrochemical carboxylation of acetophenone as a function of CO 2 concentration by using a robust finite element analysis model that incorporates each reaction step. Specifically, we show that the first electrochemical reduction of acetophenone is followed by the homogeneous chemical addition of CO 2 . The electrochemical reduction of the acetophenone-CO 2 adduct is more facile than that of acetophenone, resulting in an Electrochemical–Chemical–Electrochemical (ECE) reaction pathway that appears as a single voltammetric wave. These modeling results provide new fundamental insights into the complex microenvironment in CO 2 -rich media that produces an optimum electrochemical carboxylation rate as a function of CO 2 pressure.
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- Award ID(s):
- 1922649
- PAR ID:
- 10450437
- Date Published:
- Journal Name:
- Chemical Communications
- Volume:
- 59
- Issue:
- 38
- ISSN:
- 1359-7345
- Page Range / eLocation ID:
- 5713 to 5716
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/d2cc06560f
