Solution‐processed high‐performance organic light‐emitting diodes containing a green‐emitting multiresonant thermally activated delayed fluorescent dendrimer

Abstract

Abstract A multi‐resonance thermally activated delayed fluorescence (MR‐TADF) dendrimer emitter and a related reference MR‐TADF compound were designed, synthesized, and characterized for use as narrowband emitters in solution‐processed OLEDs. The 1 wt% doped films in PMMA film revealed that the compounds MR‐D1 and MR‐D2 showed narrowband green emission at λ PL of 490 and 495 nm and with FWHM of 23 and 29 nm, respectively. The 50 wt% doped films in mCP still show narrowband green emission at λ PL of 495 and 499 nm and with FWHM of 28 nm for MR‐D1 and MR‐D2 , respectively, while conserving the small ΔE ST of 0.14 and 0.13 eV, respectively. OLEDs containing an emissive layer consisting of 50 wt% MR‐D1 and MR‐D2 in mCP showed high EQE max of 27.7% and 21.0%, respectively, and low efficiency roll‐off of 19% and 30% at a luminance of 2000 cd/m −2 .