Organic electroluminescence device
Disclosed is an organic electroluminescence device. The device includes an anode; a cathode; and a first light-emission layer disposed between the anode and the cathode and configured for emitting blue light. The first light-emission layer comprises a host composition and a blue dopant. The blue dopant includes at least one compound represented by Chemical Formula D. The host composition contains a first host compound and a second host compound. The first host compound has a triplet energy level higher than a triplet energy level of the blue dopant, while the second host compound has a triplet energy level lower than the triplet energy level of the blue dopant. In Chemical Formula D, each of R a , R b , R c , R d and R e independently is the same as defined in the present specification.
1. An organic electroluminescence device comprising:
an anode;
a cathode; and
a first light-emission layer disposed between the anode and the cathode and configured for emitting blue light,
wherein the first light-emission layer comprises a host composition and a blue dopant,
wherein the blue dopant comprises at least one compound represented by Chemical Formula D, and the host composition comprises a first host compound and a second host compound,
wherein the first host compound is a carbazole-based compound and the second host compound is an anthracene-based compound,
wherein the carbazole-based compound is a compound represented by Chemical Formula C:
wherein, each of R d , R e , R f and R g independently represents one selected from a group consisting of hydrogen, deuterium, halogen, a substituted or unsubstituted C1 to C6 alkyl group, a substituted or unsubstituted C3 to C6 cycloalkyl group, a substituted or unsubstituted C6 to C15 aryl group, a substituted or unsubstituted C5 to C9 heteroaryl group, a substituted or unsubstituted carbazole group, a substituted or unsubstituted dibenzofuran group, a substituted or unsubstituted dibenzothiophene group, a substituted or unsubstituted trialkylsilyl group, and a substituted or unsubstituted triarylsilyl group,
each of m and p independently is an integer of 1 to 4,
each of n and o is independently an integer of 1 to 3, and
each of R x and R y independently represents a substituted or unsubstituted C6 to C50 monovalent aromatic hydrocarbon group,
wherein the anthracene-based compound is:
wherein a content of the first host compound is lower than a content of the second host compound,
wherein the first host compound has a triplet energy level higher than a triplet energy level of the blue dopant, and the second host compound has a triplet energy level lower than the triplet energy level of the blue dopant selected from the group consisting of:
wherein the organic electroluminescence device satisfies Equation I:
X+Y= 24 (Equation I)
wherein, X denotes a ratio of a mass of the first host compound to a mass of the blue dopant, and Y denotes a ratio of a mass of the second host compound to the mass of the blue dopant, Y is a rational number from 14 to 22, and a ratio between X and Y is in a range from 1:9 to 3:7.
2. The organic electroluminescence device of claim 1 , wherein Y is a rational number from 16 to 21.
3. The organic electroluminescence device of claim 1 , wherein the triplet energy level of the first host compound is in a range from 2.7 eV to 2.8 eV, and the triplet energy level of the second host compound is in a range from 1.8 eV to 1.9 eV.
4. The organic electroluminescence device of claim 1 , wherein the carbazole-based compound represented by Chemical Formula C is a compound represented by Chemical Formula C-1:
wherein, each of R d , R e , R f and R g independently represents one selected from a group consisting of hydrogen, deuterium, halogen, a substituted or unsubstituted C1 to C6 alkyl group, a substituted or unsubstituted C3 to C6 cycloalkyl group, a substituted or unsubstituted C6 to C15 aryl group, a substituted or unsubstituted C5 to C9 heteroaryl group, a substituted or unsubstituted carbazole group, a substituted or unsubstituted dibenzofuran group, a substituted or unsubstituted dibenzothiophene group, a substituted or unsubstituted trialkylsilyl group, and a substituted or unsubstituted triarylsilyl group,
each of m and p independently is an integer of 1 to 4,
each of n and o is independently an integer of 1 to 3, and
each of R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , R 8 , R 9 , and R 10 independently represents one selected from a group consisting of hydrogen, deuterium, halogen, a substituted or unsubstituted C1 to C6 alkyl group, a substituted or unsubstituted C6 to C15 aryl group, a substituted or unsubstituted carbazole group, a substituted or unsubstituted dibenzofuran group, and a substituted or unsubstituted dibenzothiophene group.
5. The organic electroluminescence device of claim 1 , wherein the carbazole-based compound is selected from the group consisting of:
6. The organic electroluminescence device of claim 1 , further comprising:
a second light-emission layer for emitting light of a wavelength longer than a blue light wavelength; and
a charge generation layer comprising an n-type charge generation layer and a p-type charge generation layer, wherein the charge generation layer is disposed between the first light-emission layer and the second light-emission layer, and the p-type charge generation layer is disposed between the n-type charge generation layer and the second light-emission layer.