2D PbS Quantum Dot Superlattices with Unprecedented Area Coverage and Homogeneity via Langmuir-Schaefer Deposition

2D PbS Quantum Dot Superlattices with Unprecedented Area Coverage and Homogeneity via Langmuir-Schaefer Deposition | 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 2D PbS Quantum Dot Superlattices with Unprecedented Area Coverage and Homogeneity via Langmuir-Schaefer Deposition Maria Antonietta Loi, Jacopo Pinna, Alexandru Mednicov, Razieh Mehrabi Koushki, and 5 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-5860939/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 09 Oct, 2025 Read the published version in Nature Communications → Version 1 posted You are reading this latest preprint version Abstract Superlattices of lead chalcogenide colloidal quantum dots hold promise to revolutionise the field of infrared optoelectronics due to their unique combination of optical and transport properties. However, the main challenge remains to form a homogeneous thin-film with long-range order avoiding cracking upon ligand exchange. This problem is particularly evident in 2D superlattices where the interactions driving the self-assembly are limited to a single plane yielding very defective films. To overcome these issues, we introduce a novel approach where external lateral pressure is applied during the self-assembly and ligand exchange, forcing the quantum dots toward each other thus avoiding the formation of cracks due to the volume shrinking. Such films consist of a hexagonal monolayer superlattice with long-range order that are crack-free over several millimetres square. The mechanism beyond the formation and ordering of the samples under external pressure is elucidated by atomistic molecular dynamic simulations. Transport measurements in an ionic gel-gated field-effect transistor reveal that increasing the external pressure during the superlattice formation leads to higher electron mobilities above 25 cm 2 /Vs thanks to better compactness, high ordering, and a higher number of nearest neighbours. These results demonstrate that colloidal quantum dot superlattices with high charge mobility can be fabricated over large areas with important implications for technological applications. Physical sciences/Nanoscience and technology/Nanoscale materials/Quantum dots Physical sciences/Nanoscience and technology/Nanoscale devices/Electronic devices Full Text Additional Declarations There is NO Competing Interest. Supplementary Files LBSI1.0JPGP.docx Supplementary Information supplmvid1.mp4 Supplementary Video 1 supplvid2.mp4 Supplementary Video 2 Cite Share Download PDF Status: Published Journal Publication published 09 Oct, 2025 Read the published version in Nature Communications → 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-5860939","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":412144447,"identity":"a89504b3-e164-45f4-bda4-f2ad8210a099","order_by":0,"name":"Maria Antonietta Loi","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAqUlEQVRIiWNgGAWjYLCCBwwSchBWAbFaEhgkjCEsA+K1MCQ2EK1Ft4H5AUNChUX69hnpF5gLiNFidoDNgCHhjETunBs5BcwziNMCdExim0TuDImcBGYe4rSwfwBpSZcgQQsP2JYECYn0A0RqOcxTcADoF8MZPG8YDhOn5Xj7xgcfKurkJdjTHz7mqSBCCwMzA8MBCIvH4AAxGpAB+wNSdYyCUTAKRsEIAQB6IS3E5qDetQAAAABJRU5ErkJggg==","orcid":"https://orcid.org/0000-0002-7985-7431","institution":"University of Groningen","correspondingAuthor":true,"prefix":"","firstName":"Maria","middleName":"Antonietta","lastName":"Loi","suffix":""},{"id":412144448,"identity":"93c8e7f3-71da-4402-bffc-e125dffa4d23","order_by":1,"name":"Jacopo Pinna","email":"","orcid":"https://orcid.org/0000-0003-1899-0113","institution":"University of Groningen","correspondingAuthor":false,"prefix":"","firstName":"Jacopo","middleName":"","lastName":"Pinna","suffix":""},{"id":412144449,"identity":"fe1be655-83e2-47d2-9939-7d5b60063e67","order_by":2,"name":"Alexandru Mednicov","email":"","orcid":"https://orcid.org/0009-0000-9221-9728","institution":"University of Groningen","correspondingAuthor":false,"prefix":"","firstName":"Alexandru","middleName":"","lastName":"Mednicov","suffix":""},{"id":412144450,"identity":"9e8f6ec3-8dd3-457f-a4e3-cbfe993303d1","order_by":3,"name":"Razieh Mehrabi Koushki","email":"","orcid":"","institution":"University of Groningen","correspondingAuthor":false,"prefix":"","firstName":"Razieh","middleName":"Mehrabi","lastName":"Koushki","suffix":""},{"id":412144451,"identity":"92c0b1a9-25ff-4dc1-bba8-4606c5f33f37","order_by":4,"name":"Majid Ahmadi","email":"","orcid":"https://orcid.org/0000-0003-2321-3060","institution":"University of Groningen","correspondingAuthor":false,"prefix":"","firstName":"Majid","middleName":"","lastName":"Ahmadi","suffix":""},{"id":412144452,"identity":"686335ed-fc6e-4f5d-9603-c9fc16523bbe","order_by":5,"name":"José Ruiz-Franco","email":"","orcid":"","institution":"University of Groningen","correspondingAuthor":false,"prefix":"","firstName":"José","middleName":"","lastName":"Ruiz-Franco","suffix":""},{"id":412144453,"identity":"1fcfe54f-3c1a-4a9e-8fcc-8ceac9a1dfc4","order_by":6,"name":"Andrea Giuntoli","email":"","orcid":"","institution":"University of Groningen","correspondingAuthor":false,"prefix":"","firstName":"Andrea","middleName":"","lastName":"Giuntoli","suffix":""},{"id":412144454,"identity":"d78b79c2-c90f-4211-8637-cc24f1419f4d","order_by":7,"name":"Bart Kooi","email":"","orcid":"https://orcid.org/0000-0002-0311-4105","institution":"University of Groningen","correspondingAuthor":false,"prefix":"","firstName":"Bart","middleName":"","lastName":"Kooi","suffix":""},{"id":412144455,"identity":"97213bdb-e2f1-42c4-8a0e-ca00c02be22e","order_by":8,"name":"Giuseppe Portale","email":"","orcid":"https://orcid.org/0000-0002-4903-3159","institution":"Univ Groningen, Zernike Inst. 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