1. Judicious Heteroatom Doping Produces High Performance Deep Blue/Near UV Multiresonant Thermally Activated Delayed Fluorescence OLEDs
- Author
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Madayanad Suresh, Subeesh, Zhang, Le, Matulaitis, Tomas, Hall, David Luke Starkey, Si, Changfeng, Ricci, Gaetano, Slawin, Alexandra Martha Zoya, Warriner, Stuart, Beljonne, David, Olivier, Yoann, Samuel, Ifor David William, Zysman-Colman, Eli, EPSRC, European Commission, The Leverhulme Trust, University of St Andrews. Institute of Behavioural and Neural Sciences, University of St Andrews. School of Chemistry, University of St Andrews. EaSTCHEM, University of St Andrews. Centre for Biophotonics, University of St Andrews. Condensed Matter Physics, University of St Andrews. School of Physics and Astronomy, and University of St Andrews. Centre for Energy Ethics
- Subjects
Mechanics of Materials ,MCP ,Mechanical Engineering ,DAS ,QD ,General Materials Science ,QD Chemistry - Abstract
Funding: Horizon 2020 Framework Programme - 838885; Leverhulme Trust - RPG-2016-047; Engineering and Physical Sciences Research Council - EP/L017008, EP/P010482/1; Fonds de la Recherche Scientifiques de Belgique - 2.5020.11; Walloon Region - n1117545; Fonds De La Recherche Scientifique - FNRS - F.4534.21. Two multiresonant thermally activated delayed fluorescence (MR-TADF) emitters are presented and it is shown how further borylation of a deep-blue MR-TADF emitter, DIDOBNA-N, both blueshifts and narrows the emission producing a new near-UV MR-TADF emitter, MesB-DIDOBNA-N, are shown. DIDOBNA-N emits bright blue light (ΦPL = 444 nm, FWHM = 64 nm, ΦPL = 81%, τd = 23 ms, 1.5 wt% in TSPO1). The deep-blue organic light-emitting diode (OLED) based on this twisted MR-TADF compound shows a very high maximum external quantum efficiency (EQEmax) of 15.3% for a device with CIEy of 0.073. The fused planar MR-TADF emitter, MesB-DIDOBNA-N shows efficient and narrowband near-UV emission (λPL = 402 nm, FWHM = 19 nm, ΦPL = 74.7%, τd = 133 ms, 1.5 wt% in TSPO1). The best OLED with MesB-DIDOBNA-N, doped in a co-host, shows the highest efficiency reported for a near-UV OLED at 16.2%. With a CIEy coordinate of 0.049, this device also shows the bluest EL reported for a MR-TADF OLED to date. Publisher PDF
- Published
- 2023