Development of a deep-blue exciplex as an emitter and a host for highly efficient and wide-color OLEDs

A deep-blue exciplex with thermally activated delayed fluorescence (TADF) at 444 nm enabled organic light-emitting diodes (OLEDs) with CIE coordinates of (0.152, 0.075) and EQE up to 4.83%, meanwhile, which can also serve as a co-host for wide color phosphorescent OLEDs.