Kinetic Models for Thermally Activated Delayed Fluorescence Photocatalysts: From Time-Resolved Spectroscopy to Photoreactions under Continuous Irradiation

Kinetic Models for Thermally Activated Delayed Fluorescence Photocatalysts: From Time-Resolved Spectroscopy to Photoreactions under Continuous Irradiation | 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 Kinetic Models for Thermally Activated Delayed Fluorescence Photocatalysts: From Time-Resolved Spectroscopy to Photoreactions under Continuous Irradiation Caterina Bellatreccia, Federica Fina, Paola Ceroni This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-9009677/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 9 You are reading this latest preprint version Abstract Photocatalysts displaying thermally activated delayed fluorescence (TADF) display complex excited-state kinetics. Several approximations have been proposed to extract radiative and non-radiative rate constants from experimentally accessible observables such as prompt and delayed fluorescence lifetimes and quantum yields. However, many of these approaches implicitly neglect the distinctive TADF character of the chromophore, and the kinetics of excited-state quenching in TADF systems has not been examined in detail. Here, we analyze the quenching kinetics of S 1 and T 1 excited states of TADF chromophores. Using analytical modeling and numerical simulations, we show that under pulsed excitation Stern-Volmer analysis is generally valid, unless very strong singlet-triplet coupling dominates and new analytical expressions are provided. Under continuous irradiation, quencher depletion leads to more complex kinetics described by quasi-steady-state treatments. Importantly, triplet quenching is generally more productive than singlet quenching because of different cage escape yields, and the highest quenching rate constant does not necessarily yield the maximum photochemical quantum yield. These results highlight the need for rigorous kinetic modeling to optimize TADF-based photochemical reactions. Full Text Additional Declarations No competing interests reported. Supplementary Files TADFkineticsSI.docx FindingtheoptimalQ0foraphotoreaction.ipynb SternVolmervalidity.ipynb Modelingaphotoreaction.ipynb Cite Share Download PDF Status: Under Review Version 1 posted Editorial decision: Revision requested 18 Mar, 2026 Reviews received at journal 17 Mar, 2026 Reviews received at journal 12 Mar, 2026 Reviewers agreed at journal 09 Mar, 2026 Reviewers agreed at journal 08 Mar, 2026 Reviewers invited by journal 06 Mar, 2026 Editor assigned by journal 06 Mar, 2026 Submission checks completed at journal 04 Mar, 2026 First submitted to journal 02 Mar, 2026 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. 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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-9009677","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":603292247,"identity":"1a3ab980-0137-451b-881b-5438f396eb4a","order_by":0,"name":"Caterina Bellatreccia","email":"","orcid":"","institution":"Alma Mater Studiorum- Università di Bologna","correspondingAuthor":false,"prefix":"","firstName":"Caterina","middleName":"","lastName":"Bellatreccia","suffix":""},{"id":603292248,"identity":"8a9fbfcc-dc28-4f14-92d9-f29478389efb","order_by":1,"name":"Federica Fina","email":"","orcid":"","institution":"Alma Mater Studiorum- 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