Aromatic‐Imide‐Based Thermally Activated Delayed Fluorescence Materials for Highly Efficient Organic Light‐Emitting Diodes

Abstract

Supportinginformation and the ORCID identification number(s) for the author(s) of this article can be found under: https://doi.Figure 6. Performance of OLEDs based on AI-Cz and AI-TBCz as emitters. a) Current density-voltage-luminance characteristics. b) EQE-luminance characteristics. Inset:E Lspectra of the devices at 10 V. Angewandte Chemie Communications 8821

Design of Conformationally Distorted Donor–Acceptor Dyads Showing Efficient Thermally Activated Delayed Fluorescence

“…17 For achieving high TADF efficiency, a small energy gap between the excited singlet and the triplet state E(S1-T1) is a prerequisite for an effective thermal up-ISC (or reverse ISC, RISC) from T1 to S1. 6,18,19 Twisted donor-acceptor systems are very promising lead structures with respect to small HOMO-LUMO overlap and thus, small E(S1-T1). 17,20,21,22 Based upon our program to develop sequential palladium-catalyzed one-pot methods for synthesizing functional organic chromophores, 23 we decided to use the Masuda borylation-Suzuki arylation (MBSA) one-pot process 24 as a key step to access predicted donor-acceptor biaryl structures.…”

Axially Chiral TADF‐Active Enantiomers Designed for Efficient Blue Circularly Polarized Electroluminescence

“…As shown in Figure S25 a, the transient decay curve shows two exponential decays at 300 K, which were assigned to a fluorescence lifetime τ PF =30 ns and a delayed component τ DF =12.6 μs. The delayed fluorescence spectra (after 5 μs and 10 μs) of the enantiomers were identical to the emission spectra without a delay (Figure S25 b), which indicates that the delayed fluorescence is related to the delayed component by RISC . The short τ DF of the enantiomer could effectively suppress the annihilation of triplet excitons in devices, thus being beneficial for low efficiency roll‐off.…”

Advances in circularly polarized electroluminescence based on chiral TADF-active materials

“…5, a pair of TADF enantiomers S,S-/R,R-CAI-Cz were designed and synthesized by introducing chiral 1,2-diaminocyclohexane into aromatic imide-based TADF units. 18 The obtained enantiomers showed excellent TADF properties with a small ΔE ST of 0.06 eV, temperature-dependent transient PL spectra, and a high PLQY of up to 98%. Moreover, the TADF enantiomers also displayed mirror-image CD and CPL activities (Fig.…”