Organic light emitting device

1. An organic light-emitting device, comprising:

a first electrode;

a second electrode facing the first electrode;

an emission layer between the first electrode and the second electrode;

a hole control layer between the first electrode and the emission layer; and

an electron control layer between the emission layer and the second electrode,

wherein the emission layer includes:

a first sub-emission layer;

a second sub-emission layer emits shorter wavelength than the first sub-emission layer; and

a third sub-emission layer emits shorter wavelength than the first and second sub-emission layers,

wherein the third sub-emission layer includes:

a mixed hole-transporting host and an electron-transporting host which form an exciplex; and

a third light-emitting dopant; and

wherein the third light-emitting dopant emits phosphorescent light and thermally activated delayed fluorescence light.

2. The organic light-emitting device as claimed in claim 1 ,

wherein a triplet energy of the exciplex is equal to or greater than triplet energy of the third light-emitting dopant.

3. The organic light-emitting device as claimed in claim 2 ,

wherein the first sub-emission layer including a first light-emitting dopant; and

a second sub-emission layer including a second light-emitting dopant; and

wherein a triplet energy of the exciplex is equal to or greater than triplet energies of the first and second light-emitting dopants.

4. The organic light-emitting device as claimed in claim 2 ,

wherein the first sub-emission layer and the second sub-emission layer emit phosphorescent light.

5. The organic light-emitting device as claimed in claim 1 ,

wherein a triplet energy of the exciplex is about 2.4 eV to about 3.0 eV.

6. The organic light-emitting device as claimed in claim 1 ,

wherein a highest occupied molecular orbital (HOMO) energy level of the hole-transporting host is −5.4 eV, and

a lowest unoccupied molecular orbital (LUMO) energy level of the hole-transporting host is −2.4 eV.

7. The organic light-emitting device as claimed in claim 1 ,

wherein a highest occupied molecular orbital (HOMO) energy level of the electron-transporting host is −5.8 eV, and

a lowest unoccupied molecular orbital (LUMO) energy level of the electron-transporting host is −2.7 eV.

8. The organic light-emitting device as claimed in claim 1 ,

wherein the electron-transporting host is organometallic complex, a spirofluorene-based compound, an oxidazole-based compound, a phenanthroline-based compound, a triazine-based compound, or a triazole-based compound.

9. The organic light-emitting device as claimed in claim 1 ,

wherein the electron control layer includes:

an electron transport layer; and

an electron injection layer on the electron transport layer, and

wherein the electron injection layer includes LiF, LiQ, Li 2 O, BaO, NaCl, Yb, CsF, RbCl, or RbI.

10. The organic light-emitting device as claimed in claim 1 ,

wherein the hole control layer includes:

a hole injection layer; and

a hole transport layer on the hole injection layer,

wherein the hole injection layer includes p-type dopant, and

wherein the p-type dopant is one of a quinone derivative, a metal oxide, and cyano group-containing compound.

11. An organic light-emitting device, comprising:

a first electrode;

a second electrode facing the first electrode;

an emission layer between the first electrode and the second electrode;

a hole control layer between the first electrode and the emission layer; and

an electron control layer between the emission layer and the second electrode,

wherein the emission layer includes:

a first sub-emission layer including a first light-emitting dopant;

a second sub-emission layer including a second light-emitting dopant; and

a third sub-emission layer including a third light-emitting dopant;

at least portions of the first to third sub-emission layers do not overlap one another,

at least one of the first sub-emission layer and the second sub-emission layer includes a mixed hole-transporting host and electron-transporting host which form an exciplex, and

a triplet energy of the exciplex is equal to or greater than triplet energies of the first light-emitting dopant and the second light-emitting dopant.

12. The organic light-emitting device as claimed in claim 11 ,

wherein a highest occupied molecular orbital (HOMO) energy level of the hole-transporting host is −5.4 eV, and

a lowest unoccupied molecular orbital (LUMO) energy level of the hole-transporting host is −2.4 eV.

13. The organic light-emitting device as claimed in claim 11 ,

wherein a highest occupied molecular orbital (HOMO) energy level of the electron-transporting host is −5.8 eV, and

a lowest unoccupied molecular orbital (LUMO) energy level of the electron-transporting host is −2.7 eV.

14. The organic light-emitting device as claimed in claim 11 ,

wherein the electron-transporting host is organometallic complex, a spirofluorene-based compound, an oxidazole-based compound, a phenanthroline-based compound, a triazine-based compound, or a triazole-based compound.

15. The organic light-emitting device as claimed in claim 11 ,

wherein the electron control layer includes:

an electron transport layer; and

an electron injection layer on the electron transport layer, and

wherein the electron injection layer includes LiF, LiQ, Li 2 O, BaO, NaCl, Yb, CsF, RbCl, or RbI.

16. The organic light-emitting device as claimed in claim 11 ,

wherein the hole control layer includes:

a hole injection layer; and

a hole transport layer on the hole injection layer,

wherein the hole injection layer includes p-type dopant, and

wherein the p-type dopant is one of a quinone derivative, a metal oxide, and cyano group-containing compound.