Hierarchical CuS Nanoflowers via Atmosphere-Controlled Sulfurization: Enhanced Visible-Light Photocatalysis

Hierarchical CuS Nanoflowers via Atmosphere-Controlled Sulfurization: Enhanced Visible-Light Photocatalysis | 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 Research Article Hierarchical CuS Nanoflowers via Atmosphere-Controlled Sulfurization: Enhanced Visible-Light Photocatalysis Gholamreza Heidari, Morteza Hajizadeh-Oghaz This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8773513/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 Hierarchical flower-like copper sulfide (CuS) nanocrystals with exceptional visible-light photocatalytic activity were synthesized via atmosphere-controlled sulfurization of electrodeposited metallic precursor films. Through systematic comparison of three sulfurization protocols—tubular furnace, sealed ampoule, and pre-oxidation approaches—we demonstrate that sulfur-saturated conditions (≥ 7 mg S) are critical for producing covellite CuS with distinctive hierarchical nanoflower morphologies (200–500 nm diameter, 89–96 m²/g surface area) on substrate-adhered films, while insufficient sulfur yields mixed oxide-sulfide phases. The optimized CuS nanoflowers exhibited superior photocatalytic performance: 94.3% Rhodamine B degradation in 120 min under visible light with rate constant 43.8 × 10⁻³ min⁻¹ (10.4-fold enhancement over P25 TiO₂), primarily through superoxide radical-mediated oxidation. The narrow bandgap (1.45 eV), high surface area, and phase purity synergistically enabled efficient visible-light harvesting and charge separation. Thermodynamic calculations rationalized the formation mechanism via preferential SO₂/SO₃ formation that prevents oxidation and maintains reducing conditions throughout the sulfurization process. Excellent reusability (90.2% activity retention after 6 cycles) demonstrates practical applicability. This atmosphere-controlled synthesis strategy provides rational design principles for scalable production of high-performance nanostructured photocatalysts, with broad implications for chalcogenide materials synthesis. Electrodeposition Copper sulfide nanoflowers Sulfurization Visible-light photocatalysis Rhodamine B degradation Nanostructured materials Thermodynamic analysis Water treatment Full Text Additional Declarations No competing interests reported. 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. 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-8773513","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":615407175,"identity":"b4038115-7372-4701-bf19-f77e7df823a5","order_by":0,"name":"Gholamreza Heidari","email":"","orcid":"","institution":"Esfarayen University of Technology","correspondingAuthor":false,"prefix":"","firstName":"Gholamreza","middleName":"","lastName":"Heidari","suffix":""},{"id":615407176,"identity":"a5aa45bf-cd73-45ad-a17e-351c284ff20b","order_by":1,"name":"Morteza Hajizadeh-Oghaz","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAABBklEQVRIiWNgGAWjYJCCD4wNDMxsQIYEY4MNkGJsPEBAB+MMJC1pIIEGorSAAVDLYTADrxZz6cMHGxh32LHz8R9+eOPjjvN2a9sPA22psYnGpcWyLy2xgfFMMtBhx4wtZ565nbztTCJQy7G03AYcWgzO8Jg/YGxjZmZjbDCT5m27nWx2AKgF6EJ8WgwbGNvqmdmY2b9J/207l2x2/iFRWg4zs7HxmEkzth2wM7tBwBbLHrbEhsS248xsPDzFlr1tyQlmN4C2JODxizkP88GGj23VyfL9xzfe+NlmZ292Pv3hgw81NrgdBiISGBiSYQKJDVARnMAAStvBBOzxKB4Fo2AUjIIRCgB/4GBtJxuQ9QAAAABJRU5ErkJggg==","orcid":"","institution":"Esfarayen University of Technology","correspondingAuthor":true,"prefix":"","firstName":"Morteza","middleName":"","lastName":"Hajizadeh-Oghaz","suffix":""}],"badges":[],"createdAt":"2026-02-03 09:10:13","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-8773513/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-8773513/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":106094023,"identity":"e1611540-7630-4e2d-a3d4-aaf2a62e64d5","added_by":"auto","created_at":"2026-04-03 11:40:45","extension":"pdf","order_by":1,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1500645,"visible":true,"origin":"","legend":"","description":"","filename":"Manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-8773513/v1_covered_2d9d2716-f9bd-4a22-a0f2-3ffbc07a5ec2.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Hierarchical CuS Nanoflowers via Atmosphere-Controlled Sulfurization: Enhanced Visible-Light Photocatalysis","fulltext":[],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":false,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"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 Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Electrodeposition, Copper sulfide nanoflowers, Sulfurization, Visible-light photocatalysis, Rhodamine B degradation, Nanostructured materials, Thermodynamic analysis, Water treatment","lastPublishedDoi":"10.21203/rs.3.rs-8773513/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-8773513/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eHierarchical flower-like copper sulfide (CuS) nanocrystals with exceptional visible-light photocatalytic activity were synthesized via atmosphere-controlled sulfurization of electrodeposited metallic precursor films. Through systematic comparison of three sulfurization protocols\u0026mdash;tubular furnace, sealed ampoule, and pre-oxidation approaches\u0026mdash;we demonstrate that sulfur-saturated conditions (\u0026ge;\u0026thinsp;7 mg S) are critical for producing covellite CuS with distinctive hierarchical nanoflower morphologies (200\u0026ndash;500 nm diameter, 89\u0026ndash;96 m\u0026sup2;/g surface area) on substrate-adhered films, while insufficient sulfur yields mixed oxide-sulfide phases. The optimized CuS nanoflowers exhibited superior photocatalytic performance: 94.3% Rhodamine B degradation in 120 min under visible light with rate constant 43.8 \u0026times; 10⁻\u0026sup3; min⁻\u0026sup1; (10.4-fold enhancement over P25 TiO₂), primarily through superoxide radical-mediated oxidation. The narrow bandgap (1.45 eV), high surface area, and phase purity synergistically enabled efficient visible-light harvesting and charge separation. Thermodynamic calculations rationalized the formation mechanism via preferential SO₂/SO₃ formation that prevents oxidation and maintains reducing conditions throughout the sulfurization process. Excellent reusability (90.2% activity retention after 6 cycles) demonstrates practical applicability. This atmosphere-controlled synthesis strategy provides rational design principles for scalable production of high-performance nanostructured photocatalysts, with broad implications for chalcogenide materials synthesis.\u003c/p\u003e","manuscriptTitle":"Hierarchical CuS Nanoflowers via Atmosphere-Controlled Sulfurization: Enhanced Visible-Light Photocatalysis","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-04-02 17:07:09","doi":"10.21203/rs.3.rs-8773513/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":"1992595b-d186-4c2b-8bb1-9f8abdfc10ae","owner":[],"postedDate":"April 2nd, 2026","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2026-04-19T12:24:43+00:00","versionOfRecord":[],"versionCreatedAt":"2026-04-02 17:07:09","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-8773513","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-8773513","identity":"rs-8773513","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}