Synthesis and characterization of host material for phosphorescent organic light emitting diodes (PHOLEDs)

Phosphorescent organic light-emitting diodes (PHOLEDs) have been attractive, because theoretical quantum efficiency of phosphorescent emitting material is four times higher than that of fluorescent emitter. We applied... [ view full abstract ]

Phosphorescent organic light-emitting diodes (PHOLEDs) have been attractive, because theoretical quantum efficiency of phosphorescent emitting material is four times higher than that of fluorescent emitter. We applied phenylquinazoline and triazine moieties which could provide good electron transport ability and the 9-phenylcarbazole and dibenzothiophene moieties which could provide good hole transport ability to obtain a bipolar host materials for PHOLEDs. Three host materials, PCPMB, DBTPMB and DPTBT were designed and synthesized, incorporating 9-phenylcarbazole(PC) and dibenzothiophene(DBT), respectively. Compounds PCPMB, DBTPMB and DPTBT were synthesized by Suzuki coupling reactions. DFT calculations were performed using Spartan` 08 software at the B3LYP level. The chemical structures were characterized by ¹H-NMR, ¹³C-NMR, GC-Mass. Thermal stability was analyzed by thermo gravimetric analysis (TGA) and differential scanning calorimetry (DSC). Optical properties of the host materials were analyzed by UV-vis absorption spectroscopy and PL spectroscopy.