High-Efficiency Solution-Processed Small-Molecule Organic Light-Emitting Diodes with Simple Structure

Abstract

Standard fabrication of multi-layered and small molecule organic light-emitting diodes (OLEDs) based entails high device fabrication cost and inefficient material use because standard fabrication method of small-molecule OLED is a vacuum thermal deposition. Therefore, minimizing the cost for OLED fabrication by using solution-process is a major challenge for mass-production. To achieve high-efficiency solution-processed OLEDs using simple structure, we synthesized novel electron transporting host materials which have large energy band gaps (4.06 – 4.28 eV) and high triplet energy levels (2.82-2.90 eV) to be used as effective host materials for all colour phosphorescent dopants. We achieved high electroluminescent efficiencies in solution-processed orange-red, green, blue, white OLEDs, and solid-state-lighting devices with our novel host materials.