Heterocyclic compound and organic electroluminescence device including the same

1. A heterocyclic compound represented by Formula 1,

wherein an absolute value of a difference between a singlet energy level and a triplet energy level of the heterocyclic compound is about 0.2 eV or less:

wherein, in Formula 1,

R 1 to R 6 are each independently a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms for forming a ring, or a substituted or unsubstituted heteroaryl group having 2 to 30 carbon atoms for forming a ring,

L is a substituted or unsubstituted arylene group having 6 to 30 carbon atoms for forming a ring, or a substituted or unsubstituted heteroarylene group having 2 to 30 carbon atoms for forming a ring,

a, b, c, d and e are each independently an integer of 0 to 4,

f is an integer of 0 to 3,

n is 0 or 1, and

Z is represented by Formula 2-1 or Formula 2-2:

wherein, in Formula 2-1,

g is 1 or 2, when g is 1, h is an integer of 0 to 4, and when g is 2, h is an integer of 0 to 3, and

R 7 is a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms for forming a ring, or a substituted or unsubstituted heteroaryl group having 2 to 30 carbon atoms for forming a ring,

wherein, in Formula 2-2,

X 1 to X 3 are each independently CR 10 or N,

at least one of X 1 to X 3 is N, and

R 8 to R 10 are each independently a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms for forming a ring, or a substituted or unsubstituted heteroaryl group having 2 to 30 carbon atoms for forming a ring,

wherein when Z is represented by Formula 2-1, n is 1.

2. The heterocyclic compound of claim 1 , wherein Z is represented by one of Formulae 3-1 to 3-9:

3. A heterocyclic compound represented by Formula 1,

wherein an absolute value of a difference between a singlet energy level and a triplet energy level of the heterocyclic compound is about 0.2 eV or less:

wherein, in Formula 1,

R 1 to R 6 are each independently a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms for forming a ring, or a substituted or unsubstituted heteroaryl group having 2 to 30 carbon atoms for forming a ring,

L is a substituted or unsubstituted arylene group having 6 to 30 carbon atoms for forming a ring, or a substituted or unsubstituted heteroarylene group having 2 to 30 carbon atoms for forming a ring,

a, b, c, d and e are each independently an integer of 0 to 4,

f is an integer of 0 to 3,

n is 0 or 1, and

Z is represented by Formula 2-1 or Formula 2-2:

wherein, in Formula 2-1,

p is 1 or 2, when g is 1, h is an integer of 0 to 4, and when g is 2, h is an integer of 0 to 3, and

R 7 is a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms for forming a ring, or a substituted or unsubstituted heteroaryl group having 2 to 30 carbon atoms for forming a ring,

wherein, in Formula 2-2,

X 1 to X 3 are each independently CR 10 or N,

at least one of X 1 to X 3 is N, and

R 8 to R 10 are each independently a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms for forming a ring, or a substituted or unsubstituted heteroaryl group having 2 to 30 carbon atoms for forming a ring, wherein Z is represented by Formula 2-2-1:

wherein, in Formula 2-2-1,

W 1 to W 5 are each independently CH or N, and

X 1 to X 3 are the same as defined above.

4. The heterocyclic compound of claim 3 , wherein a total number of N in W 1 to W 5 is 0 or 1.

5. The heterocyclic compound of claim 1 , wherein L is a substituted or unsubstituted phenylene group.

6. The heterocyclic compound of claim 1 , wherein at least one of R 1 , R 2 , R 4 , and R 5 is a substituted or unsubstituted phenyl group, or a substituted or unsubstituted carbazole group.

7. The heterocyclic compound of claim 6 , wherein at least one of R 1 , R 2 , R 4 , and R 5 is represented by one of following structures:

8. The heterocyclic compound of claim 1 , wherein a+b+d+e is 0, 1 or 2.

9. The heterocyclic compound of claim 1 , wherein the heterocyclic compound represented by Formula 1 is one selected from compounds represented in Compound Group 1:

10. An organic electroluminescence device, comprising:

a first electrode;

a hole transport region on the first electrode;

an emission layer on the hole transport region;

an electron transport region on the emission layer; and

a second electrode on the electron transport region,

wherein the emission layer comprises a heterocyclic compound represented by Formula 1, an absolute value of a difference between a singlet energy level and a triplet energy level of the heterocyclic compound being about 0.2 eV or less:

wherein, in Formula 1,

R 1 to R 6 are each independently a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms for forming a ring, or a substituted or unsubstituted heteroaryl group having 2 to 30 carbon atoms for forming a ring,

L is a substituted or unsubstituted arylene group having 6 to 30 carbon atoms for forming a ring, or a substituted or unsubstituted heteroarylene group having 2 to 30 carbon atoms for forming a ring,

a, b, c, d and e are each independently an integer of 0 to 4,

f is an integer of 0 to 3,

n is 0 or 1, and

Z is represented by Formula 2-1 or Formula 2-2:

wherein, in Formula 2-1,

g is 1 or 2, when g is 1, his an integer of 0 to 4, and when g is 2, his an integer of 0 to 3, and

R 7 is a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms for forming a ring, or a substituted or unsubstituted heteroaryl group having 2 to 30 carbon atoms for forming a ring,

wherein, in Formula 2-2,

X 1 to X 3 are each independently CR 10 or N,

at least one of X 1 to X 3 is N, and

R 8 to R 10 are each independently a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms for forming a ring, or a substituted or unsubstituted heteroaryl group having 2 to 30 carbon atoms for forming a ring,

wherein when Z is represented by Formula 2-1, n is 1.

11. The organic electroluminescence device of claim 10 , wherein the heterocyclic compound represented by Formula 1 is to emit blue light having a wavelength of less than about 470 nm.

12. The organic electroluminescence device of claim 10 , wherein the heterocyclic compound represented by Formula 1 is to emit thermally activated delayed fluorescence.

13. The organic electroluminescence device of claim 10 , wherein Z is represented by one of Formulae 3-1 to 3-9:

14. The organic electroluminescence device of claim 10 , wherein Z is represented by Formula 2-2-1:

wherein, in Formula 2-2-1,

W 1 to W 5 are each independently CH or N, and

X 1 to X 3 are the same as defined in claim 10 .

15. The organic electroluminescence device of claim 14 , wherein a total number of N in W 1 to W 5 is 0 or 1.

16. The organic electroluminescence device of claim 10 , wherein L is a substituted or unsubstituted phenylene group.

17. The organic electroluminescence device of claim 10 , wherein at least one of R 1 , R 2 , R 4 , and R 5 is a substituted or unsubstituted phenyl group, or a substituted or unsubstituted carbazole group.

18. The organic electroluminescence device of claim 10 , wherein at least one of R 1 , R 2 , R 4 , and R 5 is represented by one of following structures:

19. The organic electroluminescence device of claim 10 , wherein a+b+d+e is 0, 1 or 2.

20. The organic electroluminescence device of claim 10 , wherein the heterocyclic compound represented by Formula 1 is at least one selected from compounds represented in Compound Group 1: