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Abstract Copper-based catalyst is uniquely positioned to catalyze the hydrocarbon formations through electrochemical CO2reduction. The catalyst design freedom is limited for alloying copper with H-affinitive elements represented by platinum group metals because the latter would easily drive the hydrogen evolution reaction to override CO2reduction. We report an adept design of anchoring atomically dispersed platinum group metal species on both polycrystalline and shape-controlled Cu catalysts, which now promote targeted CO2reduction reaction while frustrating the undesired hydrogen evolution reaction. Notably, alloys with similar metal formulations but comprising small platinum or palladium clusters would fail this objective. With an appreciable amount of CO-Pd1moieties on copper surfaces, facile CO*hydrogenation to CHO*or CO-CHO*coupling is now viable as one of the main pathways on Cu(111) or Cu(100) to selectively produce CH4or C2H4through Pd-Cu dual-site pathways. The work broadens copper alloying choices for CO2reduction in aqueous phases.
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Oxygen induced promotion of electrochemical reduction of CO2 via co-electrolysis
Abstract Harnessing renewable electricity to drive the electrochemical reduction of CO2is being intensely studied for sustainable fuel production and as a means for energy storage. Copper is the only monometallic electrocatalyst capable of converting CO2to value-added products, e.g., hydrocarbons and oxygenates, but suffers from poor selectivity and mediocre activity. Multiple oxidative treatments have shown improvements in the performance of copper catalysts. However, the fundamental underpinning for such enhancement remains controversial. Here, we combine reactivity, in-situ surface-enhanced Raman spectroscopy, and computational investigations to demonstrate that the presence of surface hydroxyl species by co-electrolysis of CO2with low concentrations of O2can dramatically enhance the activity of copper catalyzed CO2electroreduction. Our results indicate that co-electrolysis of CO2with an oxidant is a promising strategy to introduce catalytically active species in electrocatalysis.
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- Award ID(s):
- 1805022
- PAR ID:
- 10178552
- Publisher / Repository:
- Nature Publishing Group
- Date Published:
- Journal Name:
- Nature Communications
- Volume:
- 11
- Issue:
- 1
- ISSN:
- 2041-1723
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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