Transport Limitations and Defect-Mediated Recombination in Lead- Free Double Perovskite Cs₂AgSbI₆: Implications for Solar-Cell Design

Transport Limitations and Defect-Mediated Recombination in Lead- Free Double Perovskite Cs₂AgSbI₆: Implications for Solar-Cell Design | 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 Transport Limitations and Defect-Mediated Recombination in Lead- Free Double Perovskite Cs₂AgSbI₆: Implications for Solar-Cell Design Mohamed Bouzidi, Abdullah A. Alatawi, Turki Alkathiri, Sultan Albarakati, and 4 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-9260183/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 Even though the defect-mediated recombination severely limits the photovoltaic performance of lead-free double perovskites, they have become a promising alternative to Pb-based absorbers. The transport mechanisms and the optoelectronic properties of Cs₂AgSbI₆ are systematically investigated in this work by combining impedance analysis, electrical transport, photoluminescence and optical spectroscopy. A highly disordered electronic structure dominated by nonradiative recombination is shown through a non-ideal charge transport, a strong photoluminescence quenching and a large Urbach energy (~ 90 meV). Based on SCAPS-1D, numerical simulations are carried out using a representative FTO/TiO₂/Cs₂AgSbI₆/Spiro-OMeTAD architecture in order to translate the experimentally observed limitations into a device-level framework. The Shockley–Read–Hall (SRH) recombination is consistently identified by the simulations as the dominant loss pathway, which results in limited photovoltaic parameters and reduced quasi-Fermi level splitting. Defect density is emphasized as the primary bottleneck in Cs₂AgSbI₆-based devices through the strong agreement between numerical trends and experimental material signatures. These results not only offer clear guidelines for defect mitigation strategies towards improved lead-free perovskite solar cells but also provide device-relevant losses, recombination and a coherent physical picture linking disorder. Physical sciences/Energy science and technology Physical sciences/Materials science Physical sciences/Optics and photonics Physical sciences/Physics Lead-free double perovskite Cs₂AgSbI₆ Defect-mediated recombination Urbach energy Photoluminescence quenching SCAPS-1D simulation Full Text Additional Declarations No competing interests reported. Supplementary Files SupportingInformation.pdf 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-9260183","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":619076864,"identity":"dde97bff-224e-4e1b-8ef0-724e118d8229","order_by":0,"name":"Mohamed Bouzidi","email":"","orcid":"","institution":"University of Ha’il","correspondingAuthor":false,"prefix":"","firstName":"Mohamed","middleName":"","lastName":"Bouzidi","suffix":""},{"id":619076865,"identity":"27e4df45-d1f7-466d-9883-4de17041c46e","order_by":1,"name":"Abdullah A. 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The transport mechanisms and the optoelectronic properties of Cs₂AgSbI₆ are systematically investigated in this work by combining impedance analysis, electrical transport, photoluminescence and optical spectroscopy. A highly disordered electronic structure dominated by nonradiative recombination is shown through a non-ideal charge transport, a strong photoluminescence quenching and a large Urbach energy (~\u0026thinsp;90 meV). Based on SCAPS-1D, numerical simulations are carried out using a representative FTO/TiO₂/Cs₂AgSbI₆/Spiro-OMeTAD architecture in order to translate the experimentally observed limitations into a device-level framework. The Shockley\u0026ndash;Read\u0026ndash;Hall (SRH) recombination is consistently identified by the simulations as the dominant loss pathway, which results in limited photovoltaic parameters and reduced quasi-Fermi level splitting. Defect density is emphasized as the primary bottleneck in Cs₂AgSbI₆-based devices through the strong agreement between numerical trends and experimental material signatures. These results not only offer clear guidelines for defect mitigation strategies towards improved lead-free perovskite solar cells but also provide device-relevant losses, recombination and a coherent physical picture linking disorder.\u003c/p\u003e","manuscriptTitle":"Transport Limitations and Defect-Mediated Recombination in Lead- Free Double Perovskite Cs₂AgSbI₆: Implications for Solar-Cell Design","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-04-08 05:42:34","doi":"10.21203/rs.3.rs-9260183/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":"47f5fe69-ec8c-47a7-b6d3-97e3318afa17","owner":[],"postedDate":"April 8th, 2026","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[{"id":65877318,"name":"Physical sciences/Energy science and technology"},{"id":65877319,"name":"Physical sciences/Materials science"},{"id":65877320,"name":"Physical sciences/Optics and photonics"},{"id":65877321,"name":"Physical sciences/Physics"}],"tags":[],"updatedAt":"2026-04-09T06:41:10+00:00","versionOfRecord":[],"versionCreatedAt":"2026-04-08 05:42:34","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-9260183","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-9260183","identity":"rs-9260183","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}