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Abstract Copper (Cu) is the most attractive electrocatalyst for CO2reduction to multi‐carbon (C2+) products with high economic value in considerable amounts. However, the rational design of a structurally stable Cu‐based catalyst that can achieve high activity and stability towards C2+products remain a grand challenge. Here, a highly stable nickel oxygenate/Cu electrocatalyst is developed with abundant NiOOH/Cu interfaces by in situ electrochemical reconstruction. The nickel oxygenate/Cu electrocatalyst achieves a superior Faradaic efficiency of 86.3 ± 3.0% and a record partial current density of 2085 A g−1for C2+products with long‐term stability. In situ experimental and theoretical studies demonstrates that the exceptional performance in generating C2+products is attributed to the presence of the NiOOH/Cu interfaces which increase *CO coverage, lower energy barrier for *CO coupling and stabilize *OCCO simultaneously. This work provides new insights into the rational design of electrocatalysts to achieve stable and efficient electrocatalytic CO2reduction capabilities.
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Selective Electrochemical Conversion of CO 2 into Methane on Ag‐Decorated Copper Microsphere
Abstract We synthesized the silver‐decorated copper microsphere via the hydrothermal method followed by photoreduction of silver ions. Sub 100 nm Ag nanoparticles anchored on the surface of Cu microspheres enhance the electrochemical performance and the selectivity of the CO2reduction into CH4. Incorporating Ag nanoparticles onto Cu lowers the charge transfer resistance, enhancing the catalyst's conductivity and active site and increasing the rate of CO2reduction. The faradaic efficiency of silver nanoparticles decorated copper microsphere for methane was 70.94 %, almost twice that of a copper microsphere (44 %). The electrochemical performance showed higher catalytic properties, stability, and faradaic efficiency of silver‐decorated copper microspheres.
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- Award ID(s):
- 2100710
- PAR ID:
- 10551819
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- ChemistryOpen
- Volume:
- 14
- Issue:
- 1
- ISSN:
- 2191-1363
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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