Highly Electroluminescent Fluorene-based Copolymer

A series of novel soluble conjugated copolymers derived from 9,9-dioctylfluorene (DOF) and pyridine (Py) are synthesized by palladium-catalyzed Suzuki coupling reaction. The DOF-Py copolymer emit blue light in the region of 438-446 nm. Highest EL quantum efficiency (0.72 %) is observed for device with 30 % Py unit in copolymer. The copolymers containing 5-30 mol % Py unit emit blue light with good external quantum efficiency and narrow lineshape. It could be a promising blue-light-emitting materials.