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In this study Cu, Sn, and bimetallic CuSnxnanoparticles were synthesized and evaluated as electrocatalysts for CO2reduction using zero gap membrane electrode assemblies. Results show bimetallic electrocatalysts with Sn contents above 10% yield formate as a primary product with Faradaic Efficiencies near 70% at 350 mA cm−2. Cu-Snxelectrocatalysts with less than 10% Sn yield CO at current densities below 350 mA cm−2and relatively lower cell potentials. When the low-Sn content bimetallic electrocatalysts were evaluated in alkaline anolytes at 350 mA cm−2, ethanol was recorded as the primary product (FE = 48.5% at Ecell≥ 3.0 V). We propose enhanced C2activity and selectivity originate from Cu dimers adjacent to Sn atoms for bimetallic electrocatalyst with low-Sn content. The C2active sites are lost when the surface Sn content exceeds 25%–38%.
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Synthesis of Composition-Tunable Ag-Cu Bimetallic Nanoparticles Through Plasma-Driven Solution Electrolysis
Bimetallic nanomaterials have shown great potential across various fields of application. However, the synthesis of many bimetallic particles can be challenging due to the immiscibility of their constituent metals. In this study, we present a synthetic strategy to produce compositionally tunable silver–copper (Ag-Cu) bimetallic nanoparticles using plasma-driven liquid surface chemistry. By using a low-pressure nonthermal radiofrequency (RF) plasma that interacts with an Ag-Cu precursor solution at varying electrode distances, we identified that the reduction of Ag and Cu salts is governed by two “orthogonal” parameters. The reduction of Cu2+ is primarily influenced by plasma electrons, whereas UV photons play a key role in the reduction of Ag+. Consequently, by adjusting the electrode distance and the precursor ratios in the plasma–liquid system, we could control the composition of Ag-Cu bimetallic nanoparticles over a wide range.
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- Award ID(s):
- 2011401
- PAR ID:
- 10590037
- Publisher / Repository:
- Nanomaterials
- Date Published:
- Journal Name:
- Nanomaterials
- Volume:
- 14
- Issue:
- 21
- ISSN:
- 2079-4991
- Page Range / eLocation ID:
- 1758
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.3390/nano14211758
