Jung, Hyejin Lee, Si Young Lee, Chan Woo Cho, Min Kyung Won, Da Hye Kim, Cheonghee Oh, Hyung-Suk Min, Byoung Koun Hwang, Yun Jeong 2024-01-19T20:31:49Z 2024-01-19T20:31:49Z 2021-09-02 2019-03-20 0002-7863 https://pubs.kist.re.kr/handle/201004/120200 In this study, we demonstrate that the initial morphology of nanoparticles can be transformed into small fragmented nanoparticles, which were densely contacted to each other, during electrochemical CO2 reduction reaction (CO2RR). Cu-based nanoparticles were directly grown on a carbon support by using cysteamine immobilization agent, and the synthesized nanoparticle catalyst showed increasing activity during initial CO2RR, doubling Faradaic efficiency of C2H4 production from 27% to 57.3%. The increased C2H4 production activity was related to the morphological transformation over reaction time. Twenty nm cubic Cu2O crystalline particles gradually experienced in situ electrochemical fragmentation into 2-4 nm small particles under the negative potential, and the fragmentation was found to be initiated from the surface of the nanocrystal. Compared to Cu@CuO nanoparticle/C or bulk Cu-0 foil, the fragmented Cu-based NP/C catalyst achieved enhanced C2+, production selectivity, accounting 87% of the total CO2RR products, and suppressed H-2 production. In-situ X-ray absorption near edge structure studies showed metallic Cu state was observed under CO2RR, but the fragmented nanoparticles were more readily reoxidized at open circuit potential inside of the electrolyte, allowing labile Cu states. The unique morphology, small nanoparticles stacked upon on another, is proposed to promote C-C coupling reaction selectivity from CO2RR by suppressing HER. English AMER CHEMICAL SOC CARBON-DIOXIDE POLYCRYSTALLINE COPPER SUBSURFACE OXYGEN OXIDATION-STATE ELECTROREDUCTION ELECTRODES MORPHOLOGY STABILITY CATALYSTS ETHYLENE Electrochemical Fragmentation of Cu2O Nanoparticles Enhancing Selective C-C Coupling from CO2 Reduction Reaction Article 10.1021/jacs.8b11237 1 JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, v.141, no.11, pp.4624 - 4633 JOURNAL OF THE AMERICAN CHEMICAL SOCIETY 141 11 4624 4633 scie scopus 000462260400020 2-s2.0-85061915621 Chemistry, Multidisciplinary Chemistry Article CARBON-DIOXIDE POLYCRYSTALLINE COPPER SUBSURFACE OXYGEN OXIDATION-STATE ELECTROREDUCTION ELECTRODES MORPHOLOGY STABILITY CATALYSTS ETHYLENE