Light-Emitting Element, Light-Emitting Device, Display Device, Lighting Device, and Electonic Device

摘要

A light-emitting element is disclosed where a host material and a hole-transport material each consist of a carbazole skeleton and another skeleton other than the carbazole skeleton. Both the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) of the hole-transport material are distributed over the carbazole skeleton, while the HOMO of the host material is distributed over the carbazole skeleton and the LUMO thereof is distributed over the skeleton other than the carbazole skeleton. This combination of the hole-transport material and the host material allows the fabrication of a light-emitting element with high emission efficiency and low driving voltage.