Construction of An Efficient Electrode with Ionomer Binding Sites for Stable Water Electrolysis

Construction of An Efficient Electrode with Ionomer Binding Sites for Stable Water Electrolysis | 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 Construction of An Efficient Electrode with Ionomer Binding Sites for Stable Water Electrolysis Hua Bing Tao, Xiankui Wei, Nanfeng Zheng, Kejie Lao, Linrui Wen, and 8 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7906062/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted You are reading this latest preprint version Abstract Performance discrepancy between laboratory-scale catalysts and practical electrodes in real devices are widely observed. However, the fundamental causes of this discrepancy remain poorly understood, hindering the translation of advanced academic technologies into industrial practice. Using representative IrO2/TiO2 anode catalysts in proton exchange membrane water electrolyzer (PEMWE) as examples, we demonstrate this gap originates from the catalyst-electrolyte interface and can be effectively addressed by the new concept of ionomer binding sites (IBSs) in this work. Although Norm-Catal. (IrO2 on rutile TiO2) exhibited fourfold higher mass activity than IBS-Catal. (IrO2 on anatase TiO2) in aqueous electrolytes, the PEMWE device employing IBS-Catal. achieved twofold higher mass activity and a 24-fold longer predicted lifetime. The key lies in the IBSs: stronger ionomer binding on exposed anatase TiO₂ facilitated efficient and robust mass transport while mitigating active site poisoning. Moreover, the IBSs also enabled a facile scale-up of electrode fabrication by slot-die coating, a typical industry process, from which a 5.5 kilowatt PEMWE stack surpassed the 2026 DOE target. This work highlights that catalyst design should pay more attention to IBSs, rather than focusing solely on active sites. Physical sciences/Chemistry/Electrochemistry/Fuel cells Physical sciences/Nanoscience and technology/Nanoscale materials PEM water electrolysis catalyst and electrode mass transport active sites ionomer binding sites Full Text Additional Declarations There is NO Competing Interest. Supplementary Files SupplementaryInformation.docx Supplementary Information Cite Share Download PDF Status: Under Review 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. 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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-7906062","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":535575119,"identity":"c3b49ecb-7d95-44d5-b3d7-bda18649e1c5","order_by":0,"name":"Hua Bing 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