In this work, two novel types of bipolar phosphorescent host materials derived from triazine and indenocarbazole, which were 5-(7-(4,6-diphenyl-1,3,5-triazin-2-yl)-9,9-dimethyl-4b,8a-dihydro-9H-fluoren-2-yl)-7,7-dimethyl-5,7-dihydroindeno[2,1-b] carbazole (m-TFFCz) and 5-(7-(4,6-diphenyl-1,3,5-triazin-2-yl)-9,9-dimethyl-4b,8a-dihydro-9H-fluoren-2-yl)-5H-benzofuro[3,2-c]carbazole (m-TFBFCz). Both host materials exhibit remarkable thermal stability, for example, their higher glass transition temperatures (T