Electroluminescent device, and display device comprising thereof

An electroluminescent device, comprising

• a first electrode and a second electrode facing each other;
• an emission layer disposed between the first electrode and the second electrode and comprising:
• a plurality of quantum dots, and
• a first material,
• wherein the quantum dots are configured to emit a first light upon excitation by light, and the first material is configured to emit a second light upon excitation by light,
• wherein the first light has a first peak wavelength and the second light has a second peak wavelength,
• wherein in a time resolved photoluminescence analysis of the emission layer, t1 for the first light is less than or equal to about 15 nanoseconds,
• wherein the first peak wavelength is less than or equal to 680 nanometers, and the second peak wavelength is less than the first peak wavelength,
• wherein a difference between the second peak wavelength and the first peak wavelength is greater than or equal to 50 nanometers, and
• wherein on an application of a voltage, the emission layer emits light of the same color as the first light,
• wherein the first material comprises a compound represented by Chemical Formula 2-1 or Chemical Formula 2-2:
• wherein, in Chemical Formula 2-1 to Chemical Formula 2-2,
• X3 and X4 are independently selected from N—Rb or C(—Rc)(—Rd), wherein Rb, Rc, and Rd are each independently selected from hydrogen, or a substituted or unsubstituted C1 to C20 alkyl group,
• R11, R12, R13, R14, R15, R16, R21, R22, R23, R24, R25, and R26 are each independently hydrogen, a C1 to C3 alkyl group, a substituted or unsubstituted C4 to C20 alkyl group, a substituted or unsubstituted C6 to C20 aryl group, or a substituted or unsubstituted C3 to C20 heteroaryl group, provided that at least one of R11 to R14 and at least one of R21 to R26 are a substituted or unsubstituted C4 to C20 alkyl group,
• when R13 or R14 is a substituted or unsubstituted C6 to C20 aryl group, or a substituted or unsubstituted C3 to C20 heteroaryl group, then it is optionally fused with an adjacent aromatic ring to provide a C8 to C40 fused ring, and
• R27 and R28 are each independently hydrogen, a C1 to C3 alkyl group, a substituted or unsubstituted C12 to C40 arylamine group, or a substituted or unsubstituted carbazolyl group,
• wherein at least one substituent of the substituted C4 to C20 alkyl group, the substituted C1 to C20 alkyl group, the substituted C6 to C20 aryl group, the substituted C3 to C20 heteroaryl group, the substituted C12 to C40 arylamine group, the substituted methylene group, the substituted C2 to C4 alkenylene group, and the substituted carbazolyl group is a halogen group, a hydroxy group, a C1 to C30 alkoxy group, a C1 to C20 alkyl group, a C6 to C30 aryl group, or a combination thereof.