Thermal Management of OLEDs Based on TADF Materials: Implication of Heat Upconversion to the Visible Light

Thermal Management of OLEDs Based on TADF Materials: Implication of Heat Upconversion to the Visible Light | 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 Thermal Management of OLEDs Based on TADF Materials: Implication of Heat Upconversion to the Visible Light Oleg Dimitriev, Daria Kuznetsova, Shih-Wei Huang, Fu-Chuan Fan, and 6 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6836729/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted You are reading this latest preprint version Abstract High temperatures normally deteriorate the performance of light-emitting diodes, leading to excessive leakage currents, material degradation, and device failure. However, a thermal activation step is necessary for proper operation of OLEDs based on thermally-activated delayed fluorescence (TADF) compounds; therefore, heat might be exploited as a useful factor and as a side energy converted to the OLED emission. Here, we show that the performance of OLEDs based on two different TADF materials can be significantly improved by heating, where thermal management is extremely dependent on the applied biases. Device heating by ~30 K above room temperature causes enhancement of the OLED’s electroluminescence by 5-6 times when operating near the turn-on voltage, while emission enhancement decreases at higher applied biases. At the same time, temperature dependencies of currents, current differential sensitivity, and activation energy for carrier injection behave differently, showing normal and abnormal regions, where currents increase and decrease with temperature, respectively. The discrepancy of temperature dependence of electroluminescence and current in the abnormal region provides increased external quantum efficiency and improved power efficiency of the device with increasing temperature. These findings suggest potential exploitation of TADF-based OLEDs in energy-saving applications and as energy upconverters pumping waste thermal energy to light emission. Physical sciences/Optics and photonics/Lasers, LEDs and light sources/Organic LEDs Physical sciences/Materials science/Materials for energy and catalysis thermally-activated delayed fluorescence OLED thermal management activation energy energy upconversion Full Text Additional Declarations There is NO Competing Interest. Cite Share Download PDF Status: Under Review 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. 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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-6836729","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":478802297,"identity":"20f25343-b080-43db-b7e4-71e1d666f299","order_by":0,"name":"Oleg Dimitriev","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAy0lEQVRIie3PMQrCMBSA4ScZjZ1bEHuFHKDoVV4ReoYODoWCZxB6CcHV4UnALtWsBR06OevmJKZZ3Ey6CeaHkAz5eAmAz/eLSQACSLg+MkBnQpANIWSWBEOcCupxKh97NY2rgokulyBq+k4iOdkS3S5cXIkhNpo0lucJQ0iTEBml6wwEuZEzjzc9eWmiOidCHFpkmBYJiNYyxfyloaX+y6EUeEx41FqmBOq0u+c0X8RVKaPnKpwFyjLlUzgq+o273u/JgLs+n8/3X70B11FMnW+sLs0AAAAASUVORK5CYII=","orcid":"https://orcid.org/0000-0002-6848-6401","institution":"V. 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