Molecular design of modifying 4-position of dibenzofuran for high temperature stability and high efficiency

•Host materials with a 4-position modified dibenzofuran as a core structure.•Pyridoindole modification of dibenzofuran for high temperature stability.•High efficiency in blue phosphorescent organic light-emitting diodes using dibenzofuran derived host materials.

A molecular design modifying 4- position of dibenzofuran with a pyridoindole moiety for high temperature stability and high efficiency was examined as an approach to develop host materials for blue phosphorescent organic light-emitting diodes. The simple pyridoindole modification of 4- position of carbazole substituted dibenzofuran lead to high glass transition temperature above 130 °C in addition to high quantum efficiency in the blue phosphorescent device.