Dibenzothiophene dioxide-benzofuro carbazole based bipolar host material for yellow and red phosphorescent OLEDs

Abstract 2-(12H-benzofuro[3,2-a]carbazol-12-yl)dibenzo[b,d]thiophene 5,5-dioxide (DBT-INFUR) is a bipolar host material for yellow and red phosphorescent OLEDs. DBT-INFUR was designed and synthesized between dibenzothiphene acceptor and benzofuro carbazole donor with a yield of 60%. We constructed two different devices, namely a yellow and a red phosphorescent OLEDs, and we compared the device properties with reference 4,4′-Bis(N-carbazolyl)-1,1′-biphenyl (CBP). DBT-INFUR based yellow phosphorescent OLED device exhibited maximum current and external quantum efficiencies of 41.07 cd/A and 16.5%, respectively and which is better than that of reference CBP based similar device (27.66 cd A, 10.15%). DBT-INFUR based red phosphorescent OLED (12.44%) revealed higher efficiencies when compared to the reference (7.64%) device. The bipolar DBT-INFUR showed excellent host properties with yellow and red phosphorescent devices.