Efficient circularly polarized thermally activated delayed fluorescence hetero-[4]helicene with carbonyl-/sulfone-bridged triarylamine structures

This work presents the first circularly polarized thermally activated delayed fluorescence hetero-[4]helicene with a carbonyl-/sulfone-bridged triarylamine structure (QPO-PhCz), demonstrating circularly polarized light emission through effective intramolecular steric hindrance and intramolecular space charge transfer. The new molecular architecture displays a good quantum yield (0.51) and clearly circularly polarized luminescence with an absolute luminescence dissymmetry factor of 1.2 x 10(-3) in dichloromethane solution. Moreover, for their racemates, characterization of the electroluminescence device shows a sky-blue emission (488 nm) and a maximum external quantum efficiency of 10.6%. Finally, the circularly polarized organic light-emitting diodes exhibit circularly polarized electroluminescence signals with an electroluminescence dissymmetry factor of +1.6 x 10(-3) and -1.1 x 10(-3) for (M)-QPO-PhCz and (P)-QPO-PhCz, respectively.

Automated summary

This study presents the first ever circularly polarized thermally activated delayed fluorescence molecule with a carbonyl-/sulfone-bridged triarylamine structure. Circularly polarized light emission is achieved through intramolecular steric hindrance and intramolecular space charge transfer. The molecule exhibits good quantum yield and clear circularly polarized luminescence in solution.