Dibenzo[b,d]furan/thiophene-fused double boron-based multiresonance emitters with narrowband ultrapure green electroluminescence

Abstract

Herein, double boron (DB)-based narrowband pure-green multiresonance (MR) emitters DBF-DBN and DBT-DBN have been designed and synthesized. Dibenzo[b,d]furan and dibenzo[b,d]thiophene as linkages between two B−N skeletons endow target DB-MR-emitters with...

RGB Thermally Activated Delayed Fluorescence Emitters for Organic Light‐Emitting Diodes toward Realizing the BT.2020 Standard

“…Most recently, Lan and coworkers reported dibenzo‐[ b , d ]furan‐ and dibenzo[ b , d ]thiophene‐fused pure‐green MR‐type emitters DBF‐DBN and DBT‐DBN . [ 77 ] The double‐sized symmetric molecular structure allow DBF‐DBN and DBT‐DBN to show narrowband pure‐green emissions with peaks at 514 and 516 nm and small FWHMs of 22 and 19 nm, respectively. The OLEDs fabricated with DBF‐DBN and DBT‐DBN exhibit ultrapure EL with peaks at 521 and 520 nm, FWHMs of 31 and 24 nm and EQE max s of 21.5% and 31.3%, respectively.…”

Efficient orange organic light-emitting diodes employing a central aniline bridged multiresonant thermally activated delayed fluorescence emitter

“…Lan and co-workers reported another two MR-TADF dimeric emitters, DBF-DBN and DBT-DBN (Scheme S1, ESI †). 24 The OLEDs with DBF-DBN and DBT-DBN emitted at 514 and 516 nm and showed EQE max of 21.5 and 31.3%, respectively. Each of these three reports documents a red-shifted emission of the dimeric emitters compared to their monomeric counterparts; however, the emission is in the green region and no example to date demonstrates that this strategy can be used to push the emission further to the red.…”

“…To date, there are only limited samples that have been reported based on this latter strategy. [22][23][24] Our group reported the first example of a dimeric MR-TADF emitter by connecting two DiKTa units (aka QAO or QAD) [25][26][27] through a single bond in DDiKTa (Scheme S1, ESI †). 22 The photoluminescence (PL) was observed to red-shift from 451 nm for DiKTa to 470 nm for DDiKTa in toluene.…”

Efficient Ultra‐Narrowband OLEDs Based on Carbazole‐Fused Dual‐Boron Embedded Multi‐Resonance Thermally Activated Delayed Fluorescence Materials

“…3) Developing novel MR‐TADF frameworks to appropriately enhance the non‐bonding character of the π‐skeleton, efficaciously minimizing the vibration coupling and vibrational relaxation. [ 18 ]…”