Realizing Efficient Deep Blue Light‐Emitting Diodes and Single Component White Light‐Emitting Diodes with Low Efficiency Roll‐Offs from Anthracene‐Based Organic Emitters

Abstract

AbstractPurely organic emitters that can efficiently utilize triplet excitons are highly desired for organic light‐emitting diodes (OLEDs). Hot exciton channel has emerged as a competitive strategy for the efficient harvest of triplet exciton to improve the OLEDs performance and suppress efficiency roll‐off in devices. Here, two deep blue emitters, OPACN and SPACN are designed and synthesized, employing diphenylanthracene (PAnP) unit as central core, sp3 hybridized O and S atom as conjugation blocker, and electron‐withdrawing cyano group as intramolecular charge transfer (ICT) introducer. Especially, OPACN presents bluer emission with electroluminescence (EL) peak at 436 nm, CIE coordinates of (0.16, 0.10), and a maximum external quantum efficiency (EQE) of 8.7%, while SPACN shows an EL peak at 444 nm, CIE coordinates of (0.17, 0.12) and a maximum EQE of 9.0%. Furthermore, the single‐component white organic light‐emitting diode (WOLED) based on OPACN exhibits dual emission from monomer and excimer with EQE of 5.4%. And even the luminance increases to 1000–10 000 cd m−2, the EQE still remains as high as 5.2% and 4.4%, respectively, showing very low efficiency roll‐offs. These results demonstrate an alternative approach for designing high‐performance deep blue OLEDs and WOLEDs based on single component.