Sn‐based materials are identified as promising catalysts for the CO2electroreduction (CO2RR) to formate (HCOO−). However, their insufficient selectivity and activity remain grand challenges. A new type of SnO2nanosheet with simultaneous N dopants and oxygen vacancies (
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.
more » « less- Award ID(s):
- 2102609
- NSF-PAR ID:
- 10375020
- Publisher / Repository:
- Springer Science + Business Media
- Date Published:
- Journal Name:
- Materials for Renewable and Sustainable Energy
- Volume:
- 11
- Issue:
- 2
- ISSN:
- 2194-1459
- Page Range / eLocation ID:
- p. 115-129
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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