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Abstract Recent emphasis on carbon dioxide utilization has necessitated the exploration of different catalyst compositions other than copper-based systems that can significantly improve the activity and selectivity towards specific CO2 reduction products at low applied potential. In this study, a binary CoTe has been reported as an efficient electrocatalyst for CO2reduction in aqueous medium under ambient conditions at neutral pH. CoTe showed high Faradaic efficiency and selectivity of 86.83 and 75%, respectively, for acetic acid at very low potential of − 0.25 V vs RHE. More intriguingly, C1 products like formic acid was formed preferentially at slightly higher applied potential achieving high formation rate of 547.24 μmol cm−2 h−1 at − 1.1 V vs RHE. CoTe showed better CO2RR activity when compared with Co3O4, which can be attributed to the enhanced electrochemical activity of the catalytically active transition metal center as well as improved intermediate adsorption on the catalyst surface. While reduced anion electronegativity and improved lattice covalency in tellurides enhance the electrochemical activity of Co, high d-electron density improves the intermediate CO adsorption on the catalyst site leading to CO2reduction at lower applied potential and high selectivity for C2products. CoTe also shows stable CO2RR catalytic activity for 50 h and low Tafel slope (50.3 mV dec–1) indicating faster reaction kinetics and robust functionality. Selective formation of value-added C2products with low energy expense can make these catalysts potentially viable for integration with other CO2capture technologies thereby, helping to close the carbon loop.
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Reduction of carbon dioxide at a plasmonically active copper–silver cathode
Electrochemically deposited copper nanostructures were coated with silver to create a plasmonically active cathode for carbon dioxide (CO 2 ) reduction. Illumination with 365 nm light, close to the peak plasmon resonance of silver, selectively enhanced 5 of the 14 typically observed copper CO 2 reduction products while simultaneously suppressing hydrogen evolution. At low overpotentials, carbon monoxide was promoted in the light and at high overpotentials ethylene, methane, formate, and allyl alcohol were enhanced upon illumination; generally C 1 products and C 2 /C 3 products containing a double carbon bond were selectively promoted under illumination. Temperature-dependent product analysis in the dark showed that local heating is not the cause of these selectivity changes. While the exact plasmonic mechanism is still unknown, these results demonstrate the potential for enhancing CO 2 reduction selectivity at copper electrodes using plasmonics.
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- Award ID(s):
- 1653430
- PAR ID:
- 10181351
- Date Published:
- Journal Name:
- Chemical Communications
- ISSN:
- 1359-7345
- 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/d0cc03215h
