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

A light-emitting device comprising:

• a first electrode;
• a first electroluminescent unit over the first electrode;
• a first intermediate layer over the first electroluminescent unit, the first intermediate layer comprising:
• a first region comprising a first electron-transport material;
• a second region comprising a second electron-transport material;
• and
• a third region comprising a hole-transport material and a first substance;
• a second electroluminescent unit over the first intermediate layer;
• and
• a second electrode over the second electroluminescent unit,
• wherein the first region comprises one of an alkaline metal element and an alkaline earth metal element,
• wherein the second electron-transport material has one of a perylene skeleton and a phenanthroline skeleton, and
• wherein the first substance is a compound having one of a cyano group and a fluoro group or a transition metal oxide compound.

A light-emitting device comprising:

• a first electrode;
• a first hole-transport layer over the first electrode;
• a first light-emitting layer over the first hole-transport layer;
• a first electron-transport layer over the first light-emitting layer;
• an intermediate layer over the first electron-transport layer, the intermediate layer comprising:
• a first region comprising a first electron-transport material;
• a second region comprising a second electron-transport material;
• and
• a third region comprising a hole-transport material and a first substance;
• a second hole-transport layer over the intermediate layer;
• a second light-emitting layer over the second hole-transport layer;
• and
• a second electrode over the second light-emitting layer,
• wherein the first region comprises one of an alkaline metal element and an alkaline earth metal element,
• wherein the second electron-transport material has one of a perylene skeleton and a nitrogen-containing condensed aromatic ring skeleton,
• wherein the second electron-transport material has a LUMO level greater than or equal to −5.0 eV and lower than or equal to −3.0 eV, and
• wherein the first substance is a compound having one of a cyano group and a fluoro group or a transition metal oxide compound.