LIGHT-EMITTING ELEMENT, LIGHT-EMITTING DEVICE AND ELECTRONIC DEVICE

摘要

A light-emitting element with improved emission efficiency is provided. The light-emitting element includes a light-emitting layer in which a first light-emitting layer and a second light-emitting layer are stacked in contact with each other over an anode, and a first substance serving as an emission center substance in the second light-emitting layer constitutes the first light-emitting layer. A second substance serving as a host material to disperse the first substance serving as an emission center substance is included in the second light-emitting layer. In the light-emitting element, the second substance is a substance having an energy gap (or triplet energy) larger than the first substance.