Yun, Hyewon Choi, Woong Shin, Dongwoo Oh, Hyung-Suk Hwang, Yun Jeong 2024-01-19T09:04:43Z 2024-01-19T09:04:43Z 2023-07-13 2023-07 2155-5435 https://pubs.kist.re.kr/handle/201004/113536 Tailoring catalyst performance is especially crucialin a zero-gapmembrane-electrode assembly (MEA) electrolyzers for electrochemicalCO(2) reduction reaction at the industrial scale. However,few studies have directly focused on MEA systems combined with operando techniques when compared to aqueous catholyte-basedflow cells or H-cells. Using the MEA system, this study demonstratesimproved catalytic performance of the AuAg bimetallic catalyst byadjusting the atomic arrangement of the alloy structure and its extrinsicproperties with a carbon support. The AuAg catalyst containing only10 at. % Au and the AgCl domain underwent atomic arrangement via AgClreduction. The catalyst with more oxidative Ag species achieved near-unityCO selectivity (97.3%) and three-fold higher CO partial current comparedto Ag nanoparticles. Operando X-ray absorption analysisof the active AuAg catalyst in the MEA cell demonstrates that theAuAg active site contained more Ag+ and under-coordinatedsurfaces. When the carbon support was properly adjusted, high CO productionactivity is achieved with a CO partial current density and mass activityof 618 mA cm(-2) and 0.824 A mg(-1), respectively, by effectively alleviating the mass transport restriction.AuAg catalysts are competitive with CO2-to-CO catalystsin MEA because their intrinsic and extrinsic properties can be properlycontrolled. English American Chemical Society Atomic Arrangement of AuAg Alloy on Carbon Support Enhances Electrochemical CO2 Reduction in Membrane Electrode Assembly Article 10.1021/acscatal.3c01044 1 ACS Catalysis, v.13, no.13, pp.9302 - 9312 ACS Catalysis 13 13 9302 9312 N scie scopus 001018990800001 Chemistry, Physical Chemistry Article GALVANIC REPLACEMENT REACTION AG-AU ELECTROCATALYSTS ELECTROREDUCTION NANOPARTICLES CATALYSTS SITU CO2 reduction AuAg alloy CO production membrane electrode assembly galvanic replacement operando XAS carbon support