Blue fluorescence from the ligand and yellow phosphorescence from the iridium complex: High-efficiency wet-processed white organic light-emitting device

Abstract

We synthesized four carbazole modified blue-emitting fluorescent ligands. These ligands coordinated with Ir3+ and four yellow-emitting phosphorescent complexes were obtained. A high-efficiency (current efficiency 20.6cd/A) yellow electrophosphorescence device was wet-fabricated using the complex as a guest. The ligands can harvest and transfer energy to the complexes and a high efficiency (∼18cd/A) white-light emitting device (CIE 0.31, 0.39) was obtained using the ligand as the blue-fluorescence emitter and the complex as the yellow-phosphorescence emitter. Therefore, the ligand can be a coordinator, an emitter and partly, a host. This is beneficial to device efficiency and saving cost for large-scale manufacturing.