Huang Y.-PTung C.-WChen T.-LHsu C.-SLiao M.-YChen H.-CHAO MING CHEN2022-12-142022-12-14202220403364https://www.scopus.com/inward/record.uri?eid=2-s2.0-85132690618&doi=10.1039%2fd2nr01478e&partnerID=40&md5=7493d46f2cf5d867f05684178e68684ehttps://scholars.lib.ntu.edu.tw/handle/123456789/626294Unravelling the dynamic characterization of electrocatalysts during the electrochemical CO2 reduction reaction (CO2RR) is a critical factor to improve the production efficiency and selectivity, since most pre-electrocatalysts undergo structural reconstruction and surface rearrangement under working conditions. Herein, a series of pre-electrocatalysts including CuO, ZnO and two different ratios of CuO/ZnO were systematically designed by a sputtering process to clarify the correlation of the dynamic characterization of Cu sites in the presence of Zn/ZnO and the product profile. The evidence provided by in situ X-ray absorption spectroscopy (XAS) indicated that appropriate Zn/ZnO levels could induce a variation in the coordination number of Cu sites via reversing Ostwald ripening. Specifically, the recrystallized Cu site with a lower coordination number exhibited a preferential production of methane (CH4). More importantly, our findings provide a promising approach for the efficient production of CH4 by in situ reconstructing Cu-based binary electrocatalysts. © 2022 The Royal Society of ChemistryCarbon dioxide; Copper; Copper oxides; Electrolysis; II-VI semiconductors; Production efficiency; Reduction; X ray absorption spectroscopy; Zinc; Zinc oxide; CH 4; CO 2 reduction; Coordination number; Critical factors; Dynamic characterization; Dynamic reconstruction; Electrochemicals; In-situ probing; Production efficiency; Reduction reaction; Electrocatalystsjournal article10.1039/d2nr01478e2-s2.0-85132690618