Exciplex hosts for blue phosphorescent organic light-emitting diodes

The host material of organic light-emitting diodes (OLEDs) has been advanced from a single host to a mixed host for high efficiency and long lifetime. Several types of mixed host have been reported in the literature, but the exciplex host has been popular as the mixed host of OLEDs. The exciplex host has been developed mostly for red and green phosphorescent OLEDs, and has upgraded device performances, but it is difficult to develop the exciplex host for blue phosphorescent OLEDs. Recently, several works demonstrated the potential of the exciplex host for blue phosphorescent OLEDs. In this paper, the exciplex host for blue OLEDs is reviewed, and its prospects are presented.