1. Exact Solution of Kinetic Analysis for Thermally Activated Delayed Fluorescence Materials
- Author
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Stefan Diesing, Eli Zysman-Colman, Fatima Bencheikh, Ifor D. W. Samuel, Paloma L. dos Santos, Hironori Kaji, Youichi Tsuchiya, Yoshimasa Wada, Chihaya Adachi, EPSRC, University of St Andrews. School of Physics and Astronomy, University of St Andrews. EaSTCHEM, University of St Andrews. Organic Semiconductor Centre, University of St Andrews. School of Chemistry, University of St Andrews. Centre for Biophotonics, and University of St Andrews. Condensed Matter Physics
- Subjects
Chemistry ,Kinetics ,Kinetic analysis ,DAS ,Rate equation ,Materials design ,QD Chemistry ,Fluorescence ,Intersystem crossing ,Reaction rate constant ,Exact solutions in general relativity ,Chemical physics ,QD ,Physical and Theoretical Chemistry - Abstract
Research at Kyushu, Kyoto and St Andrews Universities was supported by EPSRC and JSPS Core to Core grants (JSPS Core-to-core Program; EPSRC grant number EP/R035164/1). Authors are also grateful for financial support from the Program for Building Regional Innovation Ecosystems of the Ministry of Education, Culture, Sports, Science and Technology, Japan, JST ERATO Grant JPMJER1305, JSPS KAKENHI JP20H05840, and Kyulux Inc. The photophysical analysis of thermally activated delayed fluorescence (TADF) materials has become instrumental to providing insight into their stability and performance, which is not only relevant for organic light-emitting diodes (OLED), but also for other applications such as sensing, imaging and photocatalysis. Thus, a deeper understanding of the photophysics underpinning the TADF mechanism is required to push materials design further. Previously reported analyses in the literature of the kinetics of the various processes occurring in a TADF material rely on several a priori assumptions to estimate the rate constants for forward and reverse intersystem crossing (ISC and RISC, respectively). In this report, we demonstrate a method to determine these rate constants using a three-state model together with a steady-state approximation and, importantly, no additional assumptions. Further, we derive the exact rate equations, greatly facilitating a comparison of the TADF properties of structurally diverse emitters and providing a comprehensive understanding of the photophysics of these systems. Postprint Postprint
- Published
- 2021