Paper-based lead-free thin film X-ray detectors with high sensitivity and superior environmental stability

Paper-based lead-free thin film X-ray detectors with high sensitivity and superior environmental stability | 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 Paper-based lead-free thin film X-ray detectors with high sensitivity and superior environmental stability Qinghua Zhao, Yi Liu, Yingying Chen, Wenjie Gong, Xing Li, Boru Zhou, and 9 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8285989/v1 This work is licensed under a CC BY 4.0 License Status: Under Revision Version 1 posted 11 You are reading this latest preprint version Abstract Low-dimensional, lead-free halide perovskites are promising candidates for next-generation radiation detectors due to their favorable optoelectronic properties and environmental safety. Among them, Cs₃Bi₂Br₉ has thus attracted significant attention for its layered structure and intrinsic stability. However, the fabrication of Cs₃Bi₂Br₉ thin-film—critical for large-area and flexible detector applications—remains largely unexplored. Here, we demonstrate a sustainable, all-dry abrasion method to deposit Cs₃Bi₂Br₉ thin films onto biodegradable office-grade printing paper, enabling the fabrication of flexible, lead-free X-ray detectors. The resulting devices exhibit a resistivity of 6.9 × 10 9 Ω·cm and a mobility-lifetime ( μτ ) product of 9.07 × 10⁻ 4 cm² V⁻¹, yielding X-ray detection sensitivities of 660–860 μC Gy air ⁻¹ cm⁻². Reducing the electrode spacing to 50 μm further enhances sensitivity to ~28,000 μC Gy air ⁻¹ cm⁻², which is one of the largest values that reported for thin film-based X-ray detectors, indicating strong potential for miniaturized applications. In addition to high sensitivity, the devices deliver effective imaging performance with a spatial resolution of 1.0 lp/mm (with 28 cm between X-ray source and detectors) and retain stable operation after more than 30 days of air exposure. This work introduces a green and scalable platform for developing high-performance, lead-free, and environmentally sustainable X-ray detectors. Physical sciences/Engineering Physical sciences/Materials science Physical sciences/Nanoscience and technology Physical sciences/Physics Cs3Bi2Br9 perovskite thin film paper-based X-ray detector Full Text Additional Declarations No competing interests reported. Cite Share Download PDF Status: Under Revision Version 1 posted Editorial decision: Revision requested 25 Feb, 2026 Reviews received at journal 05 Feb, 2026 Reviews received at journal 05 Feb, 2026 Reviews received at journal 02 Feb, 2026 Reviewers agreed at journal 31 Jan, 2026 Reviewers agreed at journal 31 Jan, 2026 Reviewers agreed at journal 30 Jan, 2026 Reviewers invited by journal 30 Jan, 2026 Editor assigned by journal 16 Dec, 2025 Submission checks completed at journal 07 Dec, 2025 First submitted to journal 05 Dec, 2025 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-8285989","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":583609496,"identity":"6efc7dd4-5b2d-4979-8ce2-36bcc090b240","order_by":0,"name":"Qinghua Zhao","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA/0lEQVRIiWNgGAWjYDACZjACAgkg/gAVlCBaC+MMorQwIGlh5iFGC99x3sOvC9vsGORnNz98bLvjcJ7BAeaDt3kY7PJwaZE8zJdmPbMtmYFxzjFj49wzh4sNDrAlW/MwJBfj0mJwmMfMmLeNmYFZIsFMOrftduKGAzxm0jwMBxIb8GupZ2CTSP8mbQnWwv+NkBbjx7xthxl4JHLMpBkhtrDh1SIJtIWZ59xxBgmJnGLD3rb/xZKH2Ywt5xgk49TCd/6M8WeesmoG+RnpGx/8bEvL4zve/PDGmwo7nFoYDgB9AaTqYQoSINFkgEs9WAvzB2R+Ah61o2AUjIJRMEIBAGW5UQSgs+c5AAAAAElFTkSuQmCC","orcid":"","institution":"Research \u0026 Development Institute of Northwestern Polytechnical University in Shenzhen","correspondingAuthor":true,"prefix":"","firstName":"Qinghua","middleName":"","lastName":"Zhao","suffix":""},{"id":583609497,"identity":"ffcdc4ed-5e60-4051-9e85-1636e4638496","order_by":1,"name":"Yi Liu","email":"","orcid":"","institution":"Research \u0026 Development Institute of Northwestern Polytechnical University in Shenzhen","correspondingAuthor":false,"prefix":"","firstName":"Yi","middleName":"","lastName":"Liu","suffix":""},{"id":583609498,"identity":"4a057444-5899-4347-ade2-40570048d456","order_by":2,"name":"Yingying Chen","email":"","orcid":"","institution":"Research \u0026 Development Institute of Northwestern Polytechnical University in Shenzhen","correspondingAuthor":false,"prefix":"","firstName":"Yingying","middleName":"","lastName":"Chen","suffix":""},{"id":583609499,"identity":"f3bdeb8c-6ca3-417a-bd77-06feafa11f4a","order_by":3,"name":"Wenjie Gong","email":"","orcid":"","institution":"Research \u0026 Development Institute of Northwestern Polytechnical University in Shenzhen","correspondingAuthor":false,"prefix":"","firstName":"Wenjie","middleName":"","lastName":"Gong","suffix":""},{"id":583609500,"identity":"4ffbf79e-445c-45e9-8f09-b44b9241e45c","order_by":4,"name":"Xing Li","email":"","orcid":"","institution":"Research \u0026 Development Institute of Northwestern Polytechnical University in Shenzhen","correspondingAuthor":false,"prefix":"","firstName":"Xing","middleName":"","lastName":"Li","suffix":""},{"id":583609501,"identity":"2e836aff-21d1-4695-936a-29e62aa9ed4b","order_by":5,"name":"Boru Zhou","email":"","orcid":"","institution":"Tianjin University of Science and Technology","correspondingAuthor":false,"prefix":"","firstName":"Boru","middleName":"","lastName":"Zhou","suffix":""},{"id":583609502,"identity":"e91eeec2-b396-4886-a374-4f31da50edda","order_by":6,"name":"He Huang","email":"","orcid":"","institution":"Digital Publishing Department, Shaanxi Science and Technology Press","correspondingAuthor":false,"prefix":"","firstName":"He","middleName":"","lastName":"Huang","suffix":""},{"id":583609503,"identity":"28592c2b-20f6-47e5-a54a-fff7abf7039b","order_by":7,"name":"Ning Han","email":"","orcid":"","institution":"Chongqing Jiana Instruments Co , Ltd","correspondingAuthor":false,"prefix":"","firstName":"Ning","middleName":"","lastName":"Han","suffix":""},{"id":583609504,"identity":"e4ef3cd4-7b87-41d6-9cfe-e14ed3ec27e6","order_by":8,"name":"Shuyu Chen","email":"","orcid":"","institution":"Chongqing Jiana Instruments Co , Ltd","correspondingAuthor":false,"prefix":"","firstName":"Shuyu","middleName":"","lastName":"Chen","suffix":""},{"id":583609505,"identity":"6113fbc7-5569-4735-b09e-b5bb32e33dad","order_by":9,"name":"Baoqiang Zhang","email":"","orcid":"","institution":"Shaanxi Imdetek Co., Ltd","correspondingAuthor":false,"prefix":"","firstName":"Baoqiang","middleName":"","lastName":"Zhang","suffix":""},{"id":583609506,"identity":"04427860-a328-4241-974a-99aad2fe86eb","order_by":10,"name":"Jian Li","email":"","orcid":"","institution":"Shaanxi Imdetek Co., Ltd","correspondingAuthor":false,"prefix":"","firstName":"Jian","middleName":"","lastName":"Li","suffix":""},{"id":583609507,"identity":"0d2b35a2-5cd6-4fcc-8fd7-32867c998548","order_by":11,"name":"Andres Castellanos-Gomez","email":"","orcid":"","institution":"Instituto de Ciencia de Materiales de Madrid","correspondingAuthor":false,"prefix":"","firstName":"Andres","middleName":"","lastName":"Castellanos-Gomez","suffix":""},{"id":583609508,"identity":"0745f1d9-974d-4c65-a922-4fef2c9cc8d4","order_by":12,"name":"Volodymyr Gnatyuk","email":"","orcid":"","institution":"V.E. 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Among them, Cs₃Bi₂Br₉ has thus attracted significant attention for its layered structure and intrinsic stability. However, the fabrication of Cs₃Bi₂Br₉ thin-film—critical for large-area and flexible detector applications—remains largely unexplored. Here, we demonstrate a sustainable, all-dry abrasion method to deposit Cs₃Bi₂Br₉ thin films onto biodegradable office-grade printing paper, enabling the fabrication of flexible, lead-free X-ray detectors. The resulting devices exhibit a resistivity of 6.9 × 10\u003csup\u003e9\u003c/sup\u003e Ω·cm and a mobility-lifetime (\u003cem\u003eμτ\u003c/em\u003e) product of 9.07 × 10⁻\u003csup\u003e4\u003c/sup\u003e cm² V⁻¹, yielding X-ray detection sensitivities of 660–860 μC Gy\u003csub\u003eair\u003c/sub\u003e⁻¹ cm⁻². 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