Solution-processable host materials

Developing solution-processable host materials is of fundamental importance to construct high-performance solution-processed organic light-emitting diodes (s-OLEDs) because hosts can greatly suppress the triplet excitons involved in quenching phenomena. In this chapter, we provide an overview of recent advances in the molecular structure engineering of host materials for solution-processed OLEDs. Basic design tactics and the relationships between molecular structures and optoelectronic properties for the various types of hosts have been systematically summarized. A survey of the recent progress in the investigations of different hosts including unipolar host materials, bipolar host materials, thermally activated delayed fluorescence host materials, dynamic resonance host materials, and exciplex host materials is presented.