Recent Advances Of PVA/ Chitosan/ITO Nanocomposites in Structural, Optical, Dielectric, And Nonlinear Optical Properties

Recent Advances Of PVA/ Chitosan/ITO Nanocomposites in Structural, Optical, Dielectric, And Nonlinear Optical Properties | 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 Recent Advances Of PVA/ Chitosan/ITO Nanocomposites in Structural, Optical, Dielectric, And Nonlinear Optical Properties Martin Ouma Osemba This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-9131821/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 Polyvinyl alcohol/chitosan (PVA/CS)–based nanocomposite films incorporating indium tin oxide (ITO) nanoparticles were successfully synthesized via a solution-casting technique to investigate their structural, linear, and nonlinear optical properties. ITO nanoparticles were introduced at concentrations of 2–5 wt% to tailor the optoelectronic performance of the polymer matrix. X-ray diffraction analysis revealed a progressive enhancement in crystallinity with increasing ITO content, evidenced by an increase in crystallite size from 25.7 to 32.8 nm and a concomitant reduction in dislocation density and microstrain, indicating improved structural ordering. FTIR and Raman spectroscopy confirmed strong interfacial interactions between ITO nanoparticles and the PVA/CS matrix, including characteristic Sn–O vibrations and shifted ITO phonon modes, validating successful nanoparticle incorporation. SEM and EDX analyses demonstrated uniform nanoparticle dispersion at low loadings, with the onset of agglomeration observed at 5 wt% ITO. UV–Vis–NIR spectroscopy showed a systematic reduction in optical transmittance and a red shift in the absorption edge with increasing ITO content. The optical band gap decreased from 4.49 to 4.13 eV, attributed to the formation of localized states and enhanced electronic interactions within the nanocomposite. Optical constants, dielectric parameters, and dispersion energies derived from the Wemple–DiDomenico and Sellmeier models exhibited pronounced enhancement with ITO loading, reflecting increased polarizability and charge carrier density. Photoluminescence measurements revealed concentration-dependent quenching behavior and defect-related emissions, indicating modified recombination dynamics. Furthermore, significant improvements in third-order nonlinear optical susceptibility (χ⁽³⁾) and nonlinear refractive index (n₂) were observed, driven by reduced band gap energy and increased electronic polarization. These results demonstrate that low-level ITO incorporation effectively tailors the structural and optoelectronic properties of PVA/CS nanocomposites, highlighting their strong potential for advanced applications in flexible optoelectronics, photonic devices, nonlinear optics, and sensing technologies. Materials Chemistry Polymer Science Biopolymers Nanoscience ITO Polymer Optical properties Flexible optoelectronic application Full Text Additional Declarations The authors declare no competing interests. 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-9131821","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":606515149,"identity":"f4e33835-de0e-4543-80df-db04f392f13a","order_by":0,"name":"Martin Ouma Osemba","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAABCklEQVRIiWNgGAWjYNCCCgh1AEKxQSgJvFrOwLQkEKuFsQ3GIkaLbnuP6Yaf8+zs5dubHx74+cPGnkHsWJoEQ40dg2R7A1YtZmfOmN3s3ZacuOHMMYODPQlpiQ3SacckGI4lM0jzHMCu5UaO2Q3ebcwJBhI5DAd4Eg4nMEint0kwsB1gkJNIwKnl5t859fbyM3IYDv5J+G8P0fIPqEX+AU4tt3kbDjM23MhhOMyTcIAR7DDGtgMM0jj8b3bmWNltmWPHwX45LJOWnNgmnZZskdiXzCPZg8Nhx5u33XxTUw0Ksccf39jY2fNLpxne+PDNTk7iOHbvYwJwrADN5yFS/SgYBaNgFIwCLAAAyTFdk+mKoW0AAAAASUVORK5CYII=","orcid":"https://orcid.org/0009-0007-2045-4746","institution":"Mount Kenya University","correspondingAuthor":true,"prefix":"","firstName":"Martin","middleName":"Ouma","lastName":"Osemba","suffix":""}],"badges":[],"createdAt":"2026-03-16 01:29:05","currentVersionCode":1,"declarations":{"humanSubjects":false,"vertebrateSubjects":true,"conflictsOfInterestStatement":false,"humanSubjectEthicalGuidelines":false,"humanSubjectConsent":false,"humanSubjectClinicalTrial":false,"humanSubjectCaseReport":false,"vertebrateSubjectEthicalGuidelines":true},"doi":"10.21203/rs.3.rs-9131821/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-9131821/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":104783390,"identity":"48760c52-85a5-4164-97d8-7f720f220e81","added_by":"auto","created_at":"2026-03-17 07:58:49","extension":"pdf","order_by":1,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1221540,"visible":true,"origin":"","legend":"","description":"","filename":"RecentAdvancesOfPVAChitosanITOfinal.pdf","url":"https://assets-eu.researchsquare.com/files/rs-9131821/v1_covered_5cce662a-3c1a-428e-825c-1e9632aef03c.pdf"}],"financialInterests":"The authors declare no competing interests.","formattedTitle":"\u003cp\u003e\u003cstrong\u003eRecent Advances Of PVA/ Chitosan/ITO Nanocomposites in Structural, Optical, Dielectric, And Nonlinear Optical Properties\u003c/strong\u003e\u003c/p\u003e","fulltext":[],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":false,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":true,"hideJournal":true,"highlight":"","institution":"Mount Kenya University","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":"ITO, Polymer, Optical properties, Flexible optoelectronic application","lastPublishedDoi":"10.21203/rs.3.rs-9131821/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-9131821/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003ePolyvinyl alcohol/chitosan (PVA/CS)\u0026ndash;based nanocomposite films incorporating indium tin oxide (ITO) nanoparticles were successfully synthesized via a solution-casting technique to investigate their structural, linear, and nonlinear optical properties. ITO nanoparticles were introduced at concentrations of 2\u0026ndash;5 wt% to tailor the optoelectronic performance of the polymer matrix. X-ray diffraction analysis revealed a progressive enhancement in crystallinity with increasing ITO content, evidenced by an increase in crystallite size from 25.7 to 32.8 nm and a concomitant reduction in dislocation density and microstrain, indicating improved structural ordering. FTIR and Raman spectroscopy confirmed strong interfacial interactions between ITO nanoparticles and the PVA/CS matrix, including characteristic Sn\u0026ndash;O vibrations and shifted ITO phonon modes, validating successful nanoparticle incorporation. SEM and EDX analyses demonstrated uniform nanoparticle dispersion at low loadings, with the onset of agglomeration observed at 5 wt% ITO. UV\u0026ndash;Vis\u0026ndash;NIR spectroscopy showed a systematic reduction in optical transmittance and a red shift in the absorption edge with increasing ITO content. The optical band gap decreased from 4.49 to 4.13 eV, attributed to the formation of localized states and enhanced electronic interactions within the nanocomposite. Optical constants, dielectric parameters, and dispersion energies derived from the Wemple\u0026ndash;DiDomenico and Sellmeier models exhibited pronounced enhancement with ITO loading, reflecting increased polarizability and charge carrier density. Photoluminescence measurements revealed concentration-dependent quenching behavior and defect-related emissions, indicating modified recombination dynamics. Furthermore, significant improvements in third-order nonlinear optical susceptibility (χ⁽\u0026sup3;⁾) and nonlinear refractive index (n₂) were observed, driven by reduced band gap energy and increased electronic polarization. These results demonstrate that low-level ITO incorporation effectively tailors the structural and optoelectronic properties of PVA/CS nanocomposites, highlighting their strong potential for advanced applications in flexible optoelectronics, photonic devices, nonlinear optics, and sensing technologies.\u003c/p\u003e","manuscriptTitle":"Recent Advances Of PVA/ Chitosan/ITO Nanocomposites in Structural, Optical, Dielectric, And Nonlinear Optical Properties","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-03-17 03:59:38","doi":"10.21203/rs.3.rs-9131821/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":"5d14f81d-949c-4edf-8687-aff0cf3f9240","owner":[],"postedDate":"March 17th, 2026","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[{"id":64538648,"name":"Materials Chemistry"},{"id":64538649,"name":"Polymer Science"},{"id":64538650,"name":"Biopolymers"},{"id":64538651,"name":"Nanoscience"}],"tags":[],"updatedAt":"2026-03-17T03:59:38+00:00","versionOfRecord":[],"versionCreatedAt":"2026-03-17 03:59:38","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-9131821","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-9131821","identity":"rs-9131821","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}