1. Polyethylenimine‐assisted Synthesis of Au Nanoparticles for Efficient Syngas Production.
- Author
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Chung, Young‐Hoon, Ha, Min Gwan, Na, Youngseung, Park, Hee‐Young, Kim, Hyoung‐Juhn, Henkensmeier, Dirk, Yoo, Sung Jong, Kim, Jin Young, Lee, So Young, Lee, Seung Woo, Park, Hyun S., Kim, Yong‐Tae, and Jang, Jong Hyun
- Subjects
POLYMERS ,POLYETHYLENEIMINE ,SYNTHESIS gas ,ELECTROLYTIC reduction ,NANOPARTICLES ,GLOBAL warming ,DENSITY currents - Abstract
The ability to capture, store, and use CO2 is important for remediating greenhouse‐gas emissions and combatting global warming. Herein, Au nanoparticles (Au‐NPs) are synthesized for effective electrochemical CO2 reduction and syngas production, using polyethylenimine (PEI) as a ligand molecule. The PEI‐assisted synthesis provides uniformly sized 3‐nm Au NPs, whereas larger irregularly shaped NPs are formed in the absence of PEI in the synthesis solution. The Au‐NPs synthesized with PEI (PEI−Au/C, average PEI Mw=2000) exhibit improved CO2 reduction activities compared to Au‐NPs formed in the absence of PEI (bare Au NPs/C). PEI−Au/C displays a 34 % higher activity toward CO2 reduction than bare Au NPs/C; for example, PEI−Au/C exhibits a CO partial current density (jCO) of 28.6 mA cm−2 at −1.13 VRHE, while the value for bare Au NPs/C is 21.7 mA cm−2; the enhanced jCO is mainly due to the larger surface area of PEI−Au/C. Furthermore, the PEI−Au/C electrode exhibits stable performance over 64 h, with an hourly current degradation rate of 0.25 %. The developed PEI−Au/C is employed in a CO2‐reduction device coupled with an IrO2 water‐oxidation catalyst and a proton‐conducting perfluorinated membrane to form a PEI−Au/C|Nafion|IrO2 membrane‐electrode assembly. The device using PEI−Au/C as the CO2‐reduction catalyst exhibits a jCO of 4.47 mA/cm2 at 2.0 Vcell. Importantly, the resulted PEI−Au/C is appropriate for efficient syngas production with a CO ratio of around 30–50 %. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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