Light-emitting element, light-emitting device, display device, lighting device, and electronic device

A light-emitting device comprising:

• an anode;
• a light-emitting layer over the anode, the light-emitting layer comprising a first substance, a second substance and a phosphorescent substance;
• an electron-transport layer over and in contact with the light-emitting layer, the electron-transport layer comprising a first organic compound;
• a first layer over and in contact with the electron-transport layer, the first layer comprising a second organic compound;
• and
• a cathode over the first layer,
• wherein the second substance is a heteroaromatic compound,
• wherein the first organic compound has an anthracene skeleton,
• wherein at least two phenyl groups are bonded to the anthracene skeleton in the first organic compound,
• wherein the second organic compound comprises a phenanthroline skeleton,
• wherein the first organic compound has lower triplet excitation energy than the phosphorescent substance, and
• wherein the first organic compound has a deeper LUMO level than the second organic compound.