Synthesis and application of a novel 9,9-diethyl-1,2-diaryl-1,9-dihydrofluoreno[2,3-d]imidazole for blue organic light emitting diode

Abstract Two novel 2-(4-(9,9-disubstitued-9 H -fluoren-2-yl)phenyl)-9,9-diethyl-1-phenyl-1,9-dihydrofluoreno[2,3- d ]imidazole derivatives 2a and 2b were synthesized and characterized. Their photophysical and electrochemical properties, thermal stability property, and electroluminescence (EL) performance of 2b were investigated. The fabricated device based on 2b doping into 4,4′- N , N '-dicarbazole-biphenyl (5%) as an emitter present a maximum brightness of 1272 cd/m 2 at 4 V with the CIE coordinate of (0.1590, 0.0465).