Operando Insights on Stable Cu2+ Active Sites for Efficient Electrochemical CO2-to-C2H4 Conversion

Operando Insights on Stable Cu2+ Active Sites for Efficient Electrochemical CO2-to-C2H4 Conversion | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Article Operando Insights on Stable Cu2+ Active Sites for Efficient Electrochemical CO2-to-C2H4 Conversion Heng Rao, Zonghang Zhang, Qiang Xu, Jingwei Han, Ke Ren, Yinmeng Hu, and 3 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7593621/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 13 Mar, 2026 Read the published version in Nature Communications → Version 1 posted You are reading this latest preprint version Abstract Copper catalysts feature unique superiorities for the electrochemical conversion of CO2 to C2+ fuels and chemicals. Their surface oxidation states dominantly determine the reaction pathways to various products. However, most Cu-based catalysts inevitably undergo electroreduction from Cu2+ to Cu1+ or Cu0 species during the electrochemical CO2 reduction. Herein, we propose a straightforward strategy to stabilize Cu2+ ions by coordinating them with benzobistriazolate (H2BBTA), producing a novel metal-organic polymer (CuBBTA) with periodically adjacent copper atoms. Remarkably, CuBBTA exhibits superior CO2-to-C2H4 Faradic efficiency (FE) of 62.0 ± 1.9% and a half-cell C2H4 power conversion efficiency (PCE) of 34.4% in a flow cell. It also maintains stable operation for over 50 hours in a zero-gap electrolyzers, sustaining a FE > 55% at ≈ 1 A total current density. Operando X-ray absorption, Raman, and attenuated total reflection surface-enhanced infrared absorption spectroscopy (ATR-SEIRAS) reveal that the catalyst remains structurally stable with no dynamic transformation during the reaction. Online differential electrochemical mass spectrometry (DEMS), operando ATR-SEIRAS and theoretical calculations show that neighboring Cu2+ ions in the polymer provides suitably-distanced dual sites that enable the energetically favorable formation of an *COCHO intermediate. This study presents a strategic method for developing stable catalysts for efficient CO2-to-ethylene electroconversion. Physical sciences/Chemistry/Electrochemistry/Electrocatalysis Physical sciences/Chemistry/Energy Physical sciences/Chemistry/Polymer chemistry/Coordination polymers Full Text Additional Declarations There is NO Competing Interest. Supplementary Files SupportingInformation.pdf Supplementary Information Cite Share Download PDF Status: Published Journal Publication published 13 Mar, 2026 Read the published version in Nature Communications → Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-7593621","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":516442740,"identity":"7218e723-5822-46c5-91b9-e9948d533cf5","order_by":0,"name":"Heng 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