A three-step relay mechanism enables the highly selective reduction of NO3⁻ to N2 under acidic conditions

A three-step relay mechanism enables the highly selective reduction of NO3⁻ to N2 under acidic conditions | 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 A three-step relay mechanism enables the highly selective reduction of NO3⁻ to N 2 under acidic conditions Siyu Lu This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7669110/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract The electrocatalytic reduction of nitrate (NO 3 ⁻) to N 2 (NO₃RR), represents a promising approach for alleviating nitrogen pollution in water environments. Most of the current research efforts are concentrated on neutral or alkaline conditions, where precious metals or Cl⁻ are utilized to improve the efficiency of NO 3 ⁻ conversion into N 2 . However, a portion of industrial NO 3 ⁻ wastewater is acidic. necessitating a prior neutralization step that not only increases operational costs but may also result in secondary pollution. Here, we developed a three-step relay mechanism for achieving efficient NO 3 RR reactions in acidic media without the use of precious metals or Cl⁻, which includes a three-electron oxygen reduction reaction (3e⁻ ORR), electronic structure reconstruction, and NO 3 RR. Under 0.05 M H₂SO₄ and 0.1 M KNO₃, the yield and selectivity of N 2 were 10.03 mg mg cat .⁻ 1 h⁻ 1 and 81.92%, respectively, and it operated stably for 112 h at 120 mA/cm². Moreover, it demonstrates outstanding NO 3 ⁻ removal rates at concentrations of 100 mg/L and 200 mg/L. This three-step relay strategy paves the way for the application of NO₃RR under acidic conditions, thereby opening up new avenues for research in this area. Physical sciences/Chemistry/Environmental chemistry/Pollution remediation Physical sciences/Chemistry/Catalysis/Electrocatalysis Full Text Additional Declarations There is NO Competing Interest. Supplementary Files SupplementalInformation.docx Supporting information Cite Share Download PDF Status: Posted 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. 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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-7669110","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":525867988,"identity":"6d258c96-fa66-40a5-a0ee-73ef43d62fe7","order_by":0,"name":"Siyu 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conditions\u003c/p\u003e","fulltext":[],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":false,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":true,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":true,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":true,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research 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Most of the current research efforts are concentrated on neutral or alkaline conditions, where precious metals or Cl⁻ are utilized to improve the efficiency of NO\u003csub\u003e3\u003c/sub\u003e⁻ conversion into N\u003csub\u003e2\u003c/sub\u003e. However, a portion of industrial NO\u003csub\u003e3\u003c/sub\u003e⁻ wastewater is acidic. necessitating a prior neutralization step that not only increases operational costs but may also result in secondary pollution. Here, we developed a three-step relay mechanism for achieving efficient NO\u003csub\u003e3\u003c/sub\u003eRR reactions in acidic media without the use of precious metals or Cl⁻, which includes a three-electron oxygen reduction reaction (3e⁻ ORR), electronic structure reconstruction, and NO\u003csub\u003e3\u003c/sub\u003eRR. Under 0.05 M H₂SO₄ and 0.1 M KNO₃, the yield and selectivity of N\u003csub\u003e2\u003c/sub\u003e were 10.03 mg mg\u003csub\u003ecat\u003c/sub\u003e.⁻\u003csup\u003e1\u003c/sup\u003e h⁻\u003csup\u003e1\u003c/sup\u003e and 81.92%, respectively, and it operated stably for 112 h at 120 mA/cm\u0026sup2;. Moreover, it demonstrates outstanding NO\u003csub\u003e3\u003c/sub\u003e⁻ removal rates at concentrations of 100 mg/L and 200 mg/L. This three-step relay strategy paves the way for the application of NO₃RR under acidic conditions, thereby opening up new avenues for research in this area.\u003c/p\u003e","manuscriptTitle":"A three-step relay mechanism enables the highly selective reduction of NO3⁻ to N2 under acidic conditions","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-10-08 00:50:53","doi":"10.21203/rs.3.rs-7669110/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"00a592d9-0591-4774-9651-228c21344ec4","owner":[],"postedDate":"October 8th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[{"id":55929193,"name":"Physical sciences/Chemistry/Environmental chemistry/Pollution remediation"},{"id":55929194,"name":"Physical sciences/Chemistry/Catalysis/Electrocatalysis"}],"tags":[],"updatedAt":"2025-12-11T13:50:11+00:00","versionOfRecord":[],"versionCreatedAt":"2025-10-08 00:50:53","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-7669110","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7669110","identity":"rs-7669110","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}