Synthesis and device application of 3- position modified benzothieno[3,2-c]pyridine derivative

• benzofuro[3,2-c]pyridine as an electron deficient core structure.
• Bipolar host material with 9-phenylcarbazole and benzofuro[3,2-c]pyridine.
• High quantum efficiency in green phosphorescent organic light-emitting diodes.

A new electron deficient core, benzothieno[3,2-c]pyridine (3BTP) functionalized at 3- position, was developed as the electron transport unit and a derivative of 3BTP, 3-(3-(9H-carbazol-9-yl)phenyl)benzothieno[3,2-c]pyridine (Cz3BTP), was synthesized as the triplet host material for green phosphorescent organic light-emitting diodes (PHOLEDs). The Cz3BTP host showed a triplet energy of 2.63 eV and bipolar charge transport properties. Green PHOLEDs were fabricated using the Cz3BTP host and a quantum efficiency of 11.6% was achieved.