Organic light emitting device and display apparatus

1. An organic light emitting device, comprising an anode, a cathode, and an emitting layer disposed between the anode and the cathode, wherein the emitting layer comprises a host material and a dopant material doped in the host material; the host material and the dopant material satify:

|HOMO Dopant |<|HOMO Host |,|LUMO Dopant |≤|LUMO Host |;

where HOMO Dopant is a highest occupied molecular orbit (HOMO) energy level of the dopant material, HOMO Host is a HOMO energy level of the host material, LUMO Dopant is a lowest unoccupied molecular orbital (LUMO) energy level of the dopant material, and LUMO Host is a LUMO energy level of the host material:

wherein a hole block layer is further disposed between the emitting layer and the cathode, and wherein and the host material and the hole block layer satisfy:

|HOMO HBL −HOMO Host ≥0.5eV, and

E HBL ≥E Host

wherein HOMO HBL is a HOMO energy level of the hole block layer, E HBL is an electron mobility of the hole block layer, and E Host is an electron mobility of the host material, and wherein electron mobility is measured by Space Charge Limited Current (SCLC) method.

2. The organic light emitting device of claim 1 , wherein the dopant material and the hole block layer satisfy:

|HOMO HBL −HOMO Dopant |≥0.9eV.

3. The organic light emitting device of claim 1 , wherein the host material and the hole block layer satisfy:

|LUMO Host |>|LUMO HBL |

where LUMO HBL is a LUMO energy level of the hole block layer.

4. The organic light emitting device of claim 1 , wherein the dopant material and a material of the hole block layer satisfy:

T 1 HBL >T 1 Dopant ,

where T1 HBL is a lowest triplet energy of the hole block layer, and T1 Dopant is a lowest triplet energy of the dopant material.

5. The organic light emitting device of claim 1 , wherein a hole transport layer and an electron block layer are further disposed between the anode and the emitting layer, and the hole transport layer and the electron block layer satisfy:

|HOMO HTL −HOMO EBL |<0.3eV,

where HOMO HTL is a HOMO energy level of the hole transport layer, and HOMO EBL is a HOMO energy level of the electron block layer.

6. The organic light emitting device of claim 5 , wherein the electron block layer and the host material satisfy:

0.2eV≤HOMO EBL −HOMO Host |<0.5eV.

7. The organic light emitting device of claim 5 , wherein the hole transport layer and the electron block layer satisfy:

EK HTL >EK EBL ,

where EK HTL is a hole mobility of the hole transport layer, and EK E BL is a hole mobility of the electron block layer.

8. The organic light emitting device of claim 1 , wherein the host material comprises anthracene derivatives.

9. The organic light emitting device of claim 1 , wherein

the host material comprises one or more of the following compounds having the following structural formulas:

where D is deuterium.

10. The organic light emitting device of claim 1 , wherein the dopant material comprises a compound having the following structural formula:

where X is oxygen (O) or sulfur (S); Y is B, P; R1 to R3 are hydrogen, deuterium, fluorine, C1-C4 alkyl, C3-C10 cycloalkyl, C1-C30 alkylsilyl, or C6-C10 arylsilyl; R4 and R5 are hydrogen, deuterium, fluorine, C1-C4 alkyl, C3-C10 cycloalkyl, C1-C30 alkylsilyl, or C6-C30 arylsilyl, C6-C30 aryl or heteroaryl; Ar i and Ar 2 are C6-C30 aryl or heteroaryl; and R1 to R3 are the same or different.

11. The organic light emitting device of claim 1 , wherein the dopant material comprises one or more of the following compounds having the following structural formulas:

12. The organic light emitting device of claim 1 , wherein the hole block layer comprises, but is not limited to, a compound having a structure represented by the following formula:

where R1 and R2 are hydrogen, deuterium, fluorine, C1-C4 alkyl, C3-C10 cycloalkyl, C1-C30 alkylsilyl, or C6-C10 arylsilyl; Ar 1 and Ar 2 are C6-C30 aryl or heteroaryl, one of which is heteroaryl containing at least one nitrogen; R1 and R2 are the same or different; and Ar 1 and Ar 2 are different;

or

the hole block layer comprises, but is not limited to, a compound having a structure represented by the following formula:

where L is C6-C30 aryl or heteroaryl; A is a nitrogen-containing aromatic heterocyclic which contains at least one nitrogen atom; R1 and R2 are methyl or aryl; R1 and R2 are the same or different;

or

the hole block layer comprises one or more of the following compounds having the following structural formulas:

13. The organic light emitting device of claim 5 , wherein a material of the electron block layer comprises one of the compounds having the following structural formulas:

where L1-L3 are C6-C15 aryl; Ar 1 , Ar 2 are C6-C40 aryl, arylamino, or fluorenyl, Ar 1 and Ar 2 are different groups.

14. The organic light emitting device of claim 13 , wherein a material of the electron block layer comprises one or more compounds having the following structural formulas.

15. The organic light emitting device of claim 13 , wherein one of Ar 1 and Ar 2 is a substituent represented by the following structural formula:

where R1-R5 are hydrogen, deuterium, alkyl, cycloalkyl, or C6-C36 aryl;

or one of Ar 1 and Ar 2 is a substituent represented by the following structural formulas:

16. A display apparatus comprising the organic light emitting device of claim 1 .