Poly(carbazole)-Based Copolymers Containing Deep-Blue Chromophore for Polymer Light-Emitting Diode Applications

A new series of two poly(carbazole)-based copolymers (poly(9-hexyl-carbazole-co-9-(6-(3-(4-phenylquinolin-2-yl)carbazol-9-yl)hexyl)carbazole) (PCVz) and poly(9,9-dioctylfluorene-co-9-(6-(3-(4-phenylquinolin-2-yl)carbazol-9-yl)hexyl)carbazole) (PFCVz)) containing carbazoylphenylquinoline pendant groups were synthesized via the Suzuki coupling reaction for polymer light-emitting diode applications. The electro-optical properties of ITO/PEDOT/Polymer/PBD/LiF/Al devices based on these copolymers were investigated using UV-visible, photoluminescence, and electroluminescence spectroscopy. The turn-on voltages of the copolymer devices were found to be 6.0-8.0 V. The maximum brightness and luminescence efficiency of the copolymers device were found to be 230 cd . m(-2) and 0.28 cd . A(-1) at 11V, respectively.