Light emitting element and polycyclic compound for the same

A light emitting element comprising:

• a first electrode;
• a second electrode disposed on the first electrode;
• and
• an emission layer disposed between the first electrode and the second electrode, wherein
• the emission layer comprises:
• a first compound represented by Formula 1 and having a luminescence center wavelength in a range of about 440 nm to about 480 nm;
• and
• at least one of a second compound represented by Formula HT-1, a third compound represented by Formula ET-1, or a fourth compound represented by Formula M-b:
• wherein in Formula 1,
• X1 and X2 are each independently N(R0), O, or S,
• R0 is a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted hydrocarbon ring group having 6 to 60 ring-forming carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 60 ring-forming carbon atoms,
• at least one of R1 to R4, R11 to R14, and R21 to R23 is each independently a group represented by Formula 2, and
• the remainder of R1 to R4, R11 to R14, and R21 to R23 are each independently a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted amine group, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted hydrocarbon ring group having 6 to 60 ring-forming carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 60 ring-forming carbon atoms:
• wherein in Formula 2,
• X3 and X4 are each independently N(R8), O, or S,
• a1 and a2 are each independently an integer from 0 to 4,
• a3 is an integer from 0 to 2,
• R5 to R8 are each independently a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted silyl group, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 60 ring-forming carbon atoms, and
• represents a binding site to a neighboring atom:
• wherein in Formula HT-1,
• a4 is an integer from 0 to 8, and
• R9 and R10 are each independently a hydrogen atom, a deuterium atom, a substituted or unsubstituted aryl group having 6 to 60 ring-forming carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 60 ring-forming carbon atoms:
• wherein in Formula ET-1,
• at least one of Y1 to Y3 is N,
• the remainder of Y1 to Y3 are each independently C(Ra),
• Ra is a hydrogen atom, a deuterium atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 60 ring-forming carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 60 ring-forming carbon atoms,
• b1 to b3 are each independently an integer from 0 to 10,
• L1 to L3 are each independently a direct linkage, a substituted or unsubstituted arylene group having 6 to 30 ring-forming carbon atoms, or a substituted or unsubstituted heteroarylene group having 2 to 30 ring-forming carbon atoms, and
• Ar1 to Ar3 are each independently a hydrogen atom, a deuterium atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 ring-forming carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 ring-forming carbon atoms:
• wherein in Formula M-b,
• Q1 to Q4 are each independently C or N,
• C1 to C4 are each independently a substituted or unsubstituted hydrocarbon ring group having 5 to 30 ring-forming carbon atoms, or a substituted or unsubstituted heterocyclic group having 2 to 30 ring-forming carbon atoms,
• e1 to e4 are each independently 0 or 1,
• L21 to L24 are each independently a direct linkage,
• a substituted or unsubstituted divalent alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted arylene group having 6 to 30 ring-forming carbon atoms, or a substituted or unsubstituted heteroarylene group having 2 to 30 ring-forming carbon atoms,
• d1 to d4 are each independently an integer from 0 to 4, and
• R31 to R39 are each independently a hydrogen atom, a deuterium atom, a halogen atom, a cyano group, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 ring-forming carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 ring-forming carbon atoms, or are bonded to an adjacent group to form a ring.