A highly efficient red electrophosphorescent iridium(iii) complex containing phenyl quinazoline ligand in polymer light-emitting diodes

A novel iridium(III) complex (PQxD)2Ir(pic) (HPQxD, N,N,2-triphenylquinazolin-4-amine; pic, 2-picolinic acid) was synthesized and used as a triplet emitter doped in a polymeric host in solution-processed electrophosphorescent light-emitting diodes. Polymer light-emitting devices (PLEDs) with the structure of ITO/PEDOT:PSS/(70% PVK + 30% PBD):x% (PQxD)2Ir(pic)/TPBI/CsF/Al were fabricated with high external quantum efficiency. The device based on (PQxD)2Ir(pic) furnishes a maximum external quantum efficiency of 18.44% and a luminance of 7107 cd m−2 at 8% doping concentration. The Commission International de L'Eclairage (CIE) coordinates of the complex were (0.619,0.376).