阅读说明：本技术 一种以菲并咔唑为核心的化合物及其应用 (Compound with phenanthrocarbazole as core and application thereof ) 是由 孙军 胡宗学 张洋 袁江波 刘凯鹏 张宏科 于 2021-11-10 设计创作，主要内容包括：本发明属于有机电致发光功能材料及器件技术领域,涉及一种以菲并咔唑为核心的化合物,该化合物的结构式如式(1)所示。本发明提供的以菲并咔唑为核心的化合物通过特定位置引入特定的给电子基团修饰构成的全新化合物具有较高玻璃转化温度,其作为有机电致发光器件中空穴传输材料或发光材料可显著提高发光器件的效率和寿命。(The invention belongs to the technical field of organic electroluminescent functional materials and devices, and relates to a compound taking phenanthrocarbazole as a core, wherein the structural formula of the compound is shown as a formula (1). The novel compound formed by modifying the phenanthrocarbazole-based compound through introducing a specific electron-donating group into a specific position has higher glass transition temperature, and can obviously improve the efficiency and the service life of a luminescent device when being used as a hole transport material or a luminescent material in an organic electroluminescent device.)

1. A phenanthrocarbazole-core compound is characterized in that the structural formula of the phenanthrocarbazole-core compound is shown as a formula (1):

wherein the content of the first and second substances,

l represents one of a single bond or aryl; d represents an electron donating group selected from the group consisting of a substituted or unsubstituted amine group, a substituted or unsubstituted carbazolyl group, a substituted or unsubstituted phenoxazinyl group, a substituted or unsubstituted acridinyl group, a substituted or unsubstituted 10H spiro [ acridin-9, 9 '-fluorene ] group, a substituted or unsubstituted 10H spiro [ acridin-9, 9' -xanthene ] group, a substituted or unsubstituted 5-phenyl-5, 10-dihydrophenazinyl group, and a substituted or unsubstituted 10H-phenothiazinyl group.

2. The compound of claim 1, wherein D is selected from one of aryl, carbazolyl, amine, furyl, and thienyl.

3. A compound according to claim 1, wherein the aryl group represented by L is selected from the group consisting of:

4. a compound according to claim 1, wherein the electron donating group represented by D is selected from the group consisting of:

wherein the content of the first and second substances,

Ar₁and Ar₂Is represented as one of aryl and heteroaryl; r₁And R₂Is represented by aryl, alkyl, heteroarylOne of the groups; x represents an oxygen atom, a sulfur atom, C-m₁m₂、Si-m₁m₂Or N-m₃One of (1), m₁、m₂Each independently selected from hydrogen atom, methyl, phenyl or biphenyl, m₃Is phenyl; y represents one of carbon atom, nitrogen atom and oxygen atom.

5. The compound of claim 4, wherein Ar is Ar₁、Ar₂Is represented by one of phenyl, biphenyl, carbazolyl and furyl, and R is₁And R₂Is represented by one of methyl, ethyl, tertiary butyl, phenyl, biphenyl, carbazolyl and furyl.

6. The compound of claim 1, having a structural formula selected from any one of compounds 1-52:

7. use of a compound according to any one of claims 1 to 6 in an organic electroluminescent device.

8. The use according to claim 7 for increasing the luminance efficiency of an organic electroluminescent device.

9. The use according to claim 7 for increasing the lifetime of an organic electroluminescent device.

10. An organic electroluminescent device, characterized in that one of the hole transport material or the light emitting material in the organic electroluminescent device comprises at least one compound according to any one of claims 1 to 6.

Technical Field

The invention belongs to the technical field of organic electroluminescent functional materials and devices, and particularly relates to a compound taking phenanthrocarbazole as a core and application thereof.

Background

The luminous mechanism of display and lighting elements of Organic Light Emitting Diodes (OLEDs), which are self-luminous electronic elements, is a novel optoelectronic information technology that converts electrical energy directly into Light energy with the help of Organic semiconductor functional materials under the action of a direct current electric field. The light emission color can be red, green, blue, yellow alone or combined white. The biggest characteristics of the OLED light-emitting display technology are ultrathin, high response speed, ultralight weight, surface light-emitting and flexible display, can be used for manufacturing monochromatic or panchromatic displays, can be used as a novel light source technology, and can also be used for manufacturing illumination and display products or a novel backlight source technology for manufacturing liquid crystal displays.

OLEDs include two main categories of small molecule light emitting diodes and Polymer Light Emitting Diodes (PLEDs). Among them, a typical double heterostructure small molecule OLED consists of three organic layers sandwiched between electrodes. The organic layers close to the cathode and the anode are an Electron Transport Layer (ETL), a Hole Transport Layer (HTL), and sandwiched therebetween is an emission layer (EML), which is typically a host material doped with an emission material (Emitter). The PLED structure is relatively simple with a single solution processed layer combining a Light Emitting Polymer (LEP) layer and a host, charge transport function. The performance of the material plays a decisive role in the performance of the OLED luminescent device, and the excellent hole transport material can effectively improve the efficiency and prolong the service life of the device.

Common hole transport materials include carbazoles, organic amines and butadiene compounds, such as NPB, PVK, TPH, TAPC and the like. Phenanthrocarbazole has higher thermal stability due to a specific molecular conjugated structure in a molecule, and can obtain higher glass transition temperature (Tg) and higher hole mobility through electron-donating group modification. Blue light materials are always a hot point of concern in the industry, the blue light materials used in the current production line still completely depend on import and face the risk of being blocked by neck, and the homemade replacement task is very urgent. The material constructed by the invention can be used as a hole transport material or a luminescent material to improve the efficiency and the service life of an OLED device.

Disclosure of Invention

The invention aims to provide a material for improving the brightness efficiency of an OLED device and improving the performance of the device.

Based on the above purpose, the invention provides a phenanthrocarbazole-based compound, and a hole transport material or a luminescent material of an organic electroluminescent device prepared from the phenanthrocarbazole-based compound can effectively improve the luminance efficiency and the service life of the device.

In one aspect, the invention relates to a phenanthrocarbazole-core compound, wherein the structural formula of the phenanthrocarbazole-core compound is shown as formula (1):

wherein the content of the first and second substances,

l represents one of a single bond or an aryl group; d represents an electron donating group selected from the group consisting of a substituted or unsubstituted amine group, a substituted or unsubstituted carbazolyl group, a substituted or unsubstituted phenoxazinyl group, a substituted or unsubstituted acridinyl group, a substituted or unsubstituted 10H spiro [ acridin-9, 9 '-fluorene ] group, a substituted or unsubstituted 10H spiro [ acridin-9, 9' -xanthene ] group, a substituted or unsubstituted 5-phenyl-5, 10-dihydrophenazinyl group, a substituted or unsubstituted 10H-phenothiazinyl group; preferably, the substituent of D is selected from one of aryl, carbazolyl, amine, furyl and thienyl.

Further, the L represents one of aryl and heteroaryl, and is selected from substituted or unsubstituted phenyl and substituted or unsubstituted naphthyl; preferably, said L is selected from the group consisting of:

further, D represents a group selected from:

wherein the content of the first and second substances,

Ar₁and Ar₂Is represented as one of aryl and heteroaryl; r₁And R₂Is represented by one of aryl, alkyl and heteroaryl; x represents an oxygen atom, a sulfur atom, C-m₁m₂、Si-m₁m₂Or N-m₃One of (1), m₁、m₂Each independently selected from hydrogen atom, methyl, phenyl or biphenyl, m₃Is phenyl; y represents one of carbon atom, nitrogen atom and oxygen atom; preferably, Ar is₁、Ar₂Is represented by one of phenyl, biphenyl, carbazolyl and furyl, and R is₁And R₂Is represented by one of methyl, ethyl, tertiary butyl, phenyl, biphenyl, carbazolyl and furyl.

In particular, the compound of formula (1) is selected from:

further, it has been found that the compounds of formula (1) have outstanding optical properties and are particularly suitable for improving the luminance efficiency of organic electroluminescent display devices.

On the other hand, the invention also provides an organic electroluminescent device which comprises a hole transport layer, a luminescent layer, an electron transport layer and an electron injection layer, wherein the hole transport layer and the luminescent layer are made of the compound shown in the formula (1).

Compared with the prior art, the invention has the following beneficial effects or advantages:

(1) according to the compound of the formula (1), a specific electron-donating group is introduced to a specific position to modify phenanthrocarbazole to form a brand new compound, and the compound has remarkable optical property;

(2) the compound of the formula (1) improves the glass transition temperature (Tg) of a phenanthrocarbazole core structure, so that the compound is more suitable for being used as a preparation material of an organic electroluminescent device.

(3) The compound of formula (1) provided by the invention has excellent optical performance, and can be used as a hole transport layer and a light-emitting layer material, so that the efficiency and the service life of a device can be effectively improved.

Drawings

Fig. 1 is a schematic structural diagram of an organic electroluminescent device provided in an embodiment of the present invention.

In fig. 1, 1 is a substrate, 2 is an anode layer, 3 is a hole injection layer, 4 is a first hole transport layer, 5 is a second hole transport layer, 6 is a light emitting layer, 7 is a hole blocking layer, 8 is an electron transport layer, 9 is an electron injection layer, and 10 is a cathode layer.

Detailed Description

The following examples are given to illustrate the technical aspects of the present invention, but the present invention is not limited to the following examples.

Example 1

This example provides methods and procedures for preparing compound 2, compound 13, compound 16, compound 18, compound 29, compound 34, compound 40, compound 48, and compound 52, and testing their optical properties as follows:

(1) synthesis of intermediate 1-2

Adding 60g of the intermediate 1-1 into 1.5L of 1, 4-dioxane, dropwise adding 45ml of 8mol/L concentrated nitric acid at normal temperature, heating the reaction solution to 60 ℃ after dropwise adding, stirring for 30min, cooling to room temperature after the raw materials completely react, pouring the reaction solution into 3L of ice water, stirring to separate out a solid, filtering, leaching the solid with petroleum ether, and purifying with a silica gel column to obtain 16.8g of the intermediate 1-2, wherein the yield is 23.9%.

(2) Synthesis of intermediate 1

Under nitrogen flow, 10g of intermediate 1-2, 30g of triethyl phosphite and 300ml of 1, 2-dichlorobenzene are added, then the temperature is increased to 160 ℃ for reaction for 3 hours, the temperature is reduced to room temperature after the raw materials are completely reacted, the reaction solution is washed by water to be neutral, then anhydrous sodium sulfate is dried, and the intermediate 1 of 4.7g is obtained after the reaction solution is purified by silica gel column, and the yield is 52.9%.

(3) Synthesis of Compound 2

A250 ml three-necked flask was charged with 10g of intermediate 1, 14.6g of compound 2-1, 9.1g of sodium tert-butoxide, 150ml of toluene, purged with nitrogen, and then added with 86mg of tris (dibenzylideneacetone) dipalladium and 38mg of tri-tert-butylphosphine. Heating the reaction solution to 110 ℃, refluxing and stirring for reaction for 6h, monitoring by TLC (thin layer chromatography), cooling the raw materials to room temperature after complete reaction, washing the reaction solution to be neutral, drying an organic phase by using anhydrous sodium sulfate, concentrating the obtained crude product, purifying the crude product by using a silica gel column, and recrystallizing to obtain 12.6g of a compound 2 with the yield of 65.9%.

The structural characterization nuclear magnetic data for compound 1 was measured as follows:

¹H NMR(400MHz,CDCl3)δ8.20(d,j＝7.2Hz,2H),7.62-7.69(m,6H),7.47(t,j＝7.2Hz,2H),7.39(d,j＝7.2Hz,2H),7.32(d,j＝6.4Hz,2H),7.24(d,j＝6.4Hz,4H),7.08(d,j＝6.4Hz,4H),7.00(d,j＝6.4Hz,2H)。

(4) synthesis of Compound 13

A250 ml three-necked flask was charged with 10g of intermediate 1, 19.6g of compound 13-1, 9.1g of sodium tert-butoxide, 150ml of toluene, purged with nitrogen, and then added with 86mg of tris (dibenzylideneacetone) dipalladium and 38mg of tri-tert-butylphosphine. Heating the reaction solution to 110 ℃, refluxing and stirring for reaction for 6h, monitoring by TLC (thin layer chromatography), cooling the raw materials to room temperature after complete reaction, washing the reaction solution to be neutral, drying an organic phase by using anhydrous sodium sulfate, concentrating the obtained crude product, purifying the crude product by using a silica gel column, and recrystallizing to obtain 15.7g of a compound 13, wherein the yield is 67.3%.

The structural characterization nuclear magnetic data for compound 13 was measured as follows:

¹H NMR(400MHz,CDCl3)δ8.36(s,2H),8.20(d,j＝7.2Hz,2H),7.87(d,j＝6.4Hz,4H),7.62-7.69(m,8H),7.47-7.50(m,4H),1.43(s,18H)。

(5) synthesis of Compound 16

A250 ml three-necked flask was charged with 10g of intermediate 1, 18.6g of compound 16-1, 9.1g of sodium tert-butoxide, 150ml of toluene, purged with nitrogen, and then added with 86mg of tris (dibenzylideneacetone) dipalladium and 38mg of tri-tert-butylphosphine. Heating the reaction solution to 110 ℃, refluxing and stirring for reaction for 6h, monitoring by TLC (thin layer chromatography), cooling the raw materials to room temperature after complete reaction, washing the reaction solution to be neutral, drying an organic phase by using anhydrous sodium sulfate, concentrating the obtained crude product, purifying the crude product by using a silica gel column, and recrystallizing to obtain 13.8g of a compound 16 with the yield of 61.5%.

The structural characterization nuclear magnetic data for compound 16 was measured as follows:

¹H NMR(400MHz,CDCl3)δ8.55(d,j＝7.2Hz,1H),8.20(d,j＝7.2Hz,2H),7.98(d,j＝7.2Hz,1H),7.94(d,j＝7.2Hz,1H),7.87(d,j＝6.4Hz,4H),7.62-7.66(m,4H),7.54(d,j＝7.2Hz,1H),7.49(s,1H),7.47(t,j＝7.2Hz,2H),7.42(s,1H),7.39(m,3H),7.35(t,j＝7.2Hz,1H),7.31(t,j＝7.2Hz,1H),7.16(t,j＝7.2Hz,1H)。

(6) synthesis of Compound 18

A250 ml three-necked flask was charged with 10g of intermediate 1, 14.5g of compound 18-1, 9.1g of sodium tert-butoxide, 150ml of toluene, purged with nitrogen, and then added with 86mg of tris (dibenzylideneacetone) dipalladium and 38mg of tri-tert-butylphosphine. Heating the reaction solution to 110 ℃, refluxing and stirring for reaction for 6h, monitoring by TLC (thin layer chromatography), cooling the raw materials to room temperature after complete reaction, washing the reaction solution to be neutral, drying an organic phase by using anhydrous sodium sulfate, concentrating the obtained crude product, purifying the crude product by using a silica gel column, and recrystallizing to obtain 13.9g of a compound 18 with the yield of 72.9%.

The structural characterization nuclear magnetic data for compound 18 was measured as follows:

¹H NMR(400MHz,CDCl3)δ8.55(d,j＝7.2Hz,1H),8.20(d,j＝7.2Hz,2H),7.94(d,j＝7.2Hz,1H),7.72(d,j＝7.2Hz,1H),7.58-7.67(m,8H),7.47-7.50(m,4H),7.35-7.39(m,4H),7.16(t,j＝7.2Hz,1H)。

(7) synthesis of Compound 29

A250 ml three-necked flask was charged with 10g of intermediate 1, 20.3g of compound 29-1, 9.1g of sodium tert-butoxide, 150ml of toluene, purged with nitrogen, and then added with 86mg of tris (dibenzylideneacetone) dipalladium and 38mg of tri-tert-butylphosphine. Heating the reaction solution to 110 ℃, refluxing and stirring for reaction for 6h, monitoring by TLC (thin layer chromatography), cooling the raw materials to room temperature after complete reaction, washing the reaction solution to be neutral, drying an organic phase by using anhydrous sodium sulfate, concentrating the obtained crude product, purifying the crude product by using a silica gel column, and recrystallizing to obtain 16.1g of a compound 29, wherein the yield is 67.2%.

The structural characterization nuclear magnetic data for compound 29 was measured as follows:

¹H NMR(400MHz,CDCl3)δ8.20(m,3H),8.15(d,j＝6.8Hz,1H),7.81(d,j＝6.8Hz,1H),7.75(d,j＝6.4Hz,2H),7.55-7.69(m,10H),7.47-7.50(m,6H),7.37-7.41(m,5H),7.32(d,j＝6.4Hz,2H)。

(8) synthesis of Compound 34

A250 ml three-necked flask was charged with 10g of intermediate 1, 22.1g of compound 34-1, 9.1g of sodium tert-butoxide, 150ml of toluene, purged with nitrogen, and then added with 86mg of tris (dibenzylideneacetone) dipalladium and 38mg of tri-tert-butylphosphine. Heating the reaction solution to 110 ℃, refluxing and stirring for reaction for 6h, monitoring by TLC (thin layer chromatography), cooling the raw materials to room temperature after complete reaction, washing the reaction solution to be neutral, drying an organic phase by using anhydrous sodium sulfate, concentrating the obtained crude product, purifying the crude product by using a silica gel column, and recrystallizing to obtain 16.1g of a compound 34 with the yield of 63.5%.

The structural characterization nuclear magnetic data for compound 34 was measured as follows:

¹H NMR(400MHz,CDCl3)δ8.20(d,j＝7.2Hz,2H),7.98(d,j＝6.8Hz,1H),7.75(d,j＝6.4Hz,2H),7.62-7.69(m,7H),7.55(m,3H),7.47-7.49(m,4H),7.37-7.41(m,6H),7.28-7.32(m,4H),6.97(d,j＝6.8Hz,1H)。

(9) synthesis of Compound 40

A250 ml three-necked flask was charged with 10g of intermediate 1, 23.3g of compound 2-1, 9.1g of sodium tert-butoxide, 150ml of toluene, purged with nitrogen, and then added with 86mg of tris (dibenzylideneacetone) dipalladium and 38mg of tri-tert-butylphosphine. Heating the reaction solution to 110 ℃, refluxing and stirring for reaction for 6h, monitoring by TLC (thin layer chromatography), cooling the raw materials to room temperature after complete reaction, washing the reaction solution to be neutral, drying an organic phase by using anhydrous sodium sulfate, concentrating the obtained crude product, purifying the crude product by using a silica gel column, and recrystallizing to obtain 16.2g of a compound 40 with the yield of 61.2%.

The structural characterization of compound 40 was measured as follows:

¹H NMR(400MHz,CDCl3)δ8.20(d,j＝7.2Hz,2H),7.90(d,j＝6.8Hz,1H),7.75(d,j＝6.4Hz,2H),7.62-7.69(m,6H),7.55(m,4H),7.47-7.49(m,4H),7.37-7.41(m,6H),7.28-7.34(m,4H),7.06(d,j＝6.8Hz,1H),1.69(s,6H)。

(10) synthesis of Compound 48

A250 ml three-necked flask was charged with 10g of intermediate 1, 15.2g of compound 48-1, 9.1g of sodium tert-butoxide, 150ml of toluene, purged with nitrogen, and then added with 86mg of tris (dibenzylideneacetone) dipalladium and 38mg of tri-tert-butylphosphine. Heating the reaction solution to 110 ℃, refluxing and stirring for reaction for 6h, monitoring by TLC (thin layer chromatography), cooling the raw materials to room temperature after complete reaction, washing the reaction solution to be neutral, drying an organic phase by using anhydrous sodium sulfate, concentrating the obtained crude product, purifying the crude product by using a silica gel column, and recrystallizing to obtain 14.4g of a compound 48 with the yield of 73.2%.

The structural characterization nuclear magnetic data for compound 48 was measured as follows:

¹H NMR(400MHz,CDCl3)δ8.20(d,j＝7.2Hz,2H),7.62-7.69(m,6H),7.47(d,j＝7.2Hz,2H),7.39(d,j＝7.2Hz,2H),7.32(d,j＝6.4Hz,2H),7.14(d,j＝7.6Hz,2H),7.01(t,j＝7.6Hz,4H),6.96(d,j＝7.6Hz,2H)。

(11) synthesis of Compound 52

A250 ml three-necked flask was charged with 10g of intermediate 1, 22.0g of compound 52-1, 9.1g of sodium tert-butoxide, 150ml of toluene, purged with nitrogen, and then added with 86mg of tris (dibenzylideneacetone) dipalladium and 38mg of tri-tert-butylphosphine. Heating the reaction solution to 110 ℃, refluxing and stirring for reaction for 6h, monitoring by TLC (thin layer chromatography), cooling the raw materials to room temperature after complete reaction, washing the reaction solution to be neutral, drying an organic phase by using anhydrous sodium sulfate, concentrating the obtained crude product, purifying the crude product by using a silica gel column, and recrystallizing to obtain 16.0g of a compound 52, wherein the yield is 63.5%.

The structural characterization nuclear magnetic data for compound 52 was measured as follows:

¹H NMR(400MHz,CDCl3)δ8.20(d,j＝7.2Hz,2H),7.90(d,j＝6.8Hz,2H),7.62-7.69(m,6H),7.56(d,j＝6.8Hz,2H),7.47(t,j＝7.2Hz,2H),7.38(m,4H),7.32(d,j＝6.4Hz,2H),7.28(d,j＝6.8Hz,2H),7.17-7.19(m,4H),7.14(d,j＝6.8Hz,2H),6.95(t,j＝6.8Hz,2H)。

(12) quantitative calculation of Tg, HOMO/LUMO and excited states

The compounds provided above and the conventional materials TCTA and BD01 were subjected to Tg, front track level, and excited state 1 tests, respectively, and the specific results are shown in table 1.

TABLE 1 HOMO, LUMO, Tg and excited state values of phenanthrocarbazole-based compounds

Compound (I)	HOMO(eV)	LUMO(eV)	Excited state 1(eV)	Tg(℃)
					Compound 2	-4.84	-1.58	2.762	126
Compound 13	-4.98	-1.72	2.755	132
					Compound 16	-4.99	-1.74	2.754	128
Compound 18	-4.77	-1.51	2.768	135
					Compound 29	-4.84	-1.58	2.761	142
Compound 34	-4.84	-1.59	2.759	138
					Compound 40	-4.85	-1.60	2.753	127
Compound 48	-4.91	-1.73	2.746	140
					Compound 52	-4.98	-1.73	2.762	151
TCTA	-5.20	-1.4	/	117
					BD01	-4.69	-1.59	2.661	/

Note: the glass transition temperature Tg is determined by a differential scanning calorimeter (DSC, Mettler DSC3+ STAR), the temperature rise rate is 10 ℃/min; the energy level and energy of the front line orbit of the compound are obtained by quantitative calculation simulation software.

As can be seen from Table 1, the organic compound of the present invention has a higher HOMO value, and is useful for hole transport in an OLED device as a hole transport layer, thereby reducing the voltage of the device. The organic electroluminescent device may be a phosphorescent device or a device containing a TADF material or a fluorescent device without particular limitation. Therefore, when the compound taking phenanthrocarbazole as a donor is applied to an OLED device, the luminous efficiency of the device can be effectively improved.

Example 2

This example provides the application effect of the phenanthrocarbazole-based compound prepared in example 1 in an organic electroluminescent device. The structure of the organic electroluminescent device is specifically shown in fig. 1.

(1) Constitution of organic electroluminescent device

The organic electroluminescent device used in the present embodiment is constituted by including a substrate 1, an anode layer 2, a hole injection layer 3, a first hole transport layer 4, a second hole transport layer 5, a light emitting layer 6, a hole blocking layer 7, an electron transport layer 8, an electron injection layer 9, and a cathode layer 10, which are sequentially stacked.

Wherein, the anode layer 2 is made of Indium Tin Oxide (ITO) with high work function, the hole injection layer 3 is made of HAT-CN with the thickness of 5 nm; NPB is selected as the material of the first hole transport layer 4, and the thickness is 60 nm; the material of the second hole transport layer 5 is compound 2, and the thickness is 15 nm; the light-emitting layer 6 used BH1 as a host material and BD01 as a light-emitting material, and had a doping ratio of 5% and a thickness of 30 nm; TPBI is selected as the material of the hole blocking layer 7, and the thickness is 10 nm; the material of the electron transport layer 8 is ET-1, and the thickness is 35 nm; liq is selected as the material of the electron injection layer 9, and the thickness is 2 nm; the cathode layer is made of Al and has a thickness of 100 nm.

The structural formula of the basic material used by each functional layer in the device is as follows:

(2) preparation steps of organic electroluminescent device

The specific preparation steps of the organic electroluminescent device containing the compound 2 used in the present embodiment are as follows:

1) cleaning an ITO anode on transparent glass or a plastic substrate, respectively ultrasonically cleaning the ITO anode for 20 minutes by using deionized water, acetone and ethanol, and then carrying out Plasma (Plasma) treatment for 5 minutes in an oxygen atmosphere;

2) evaporating a hole injection layer material HAT-CN on the ITO anode layer in a vacuum evaporation mode, wherein the thickness of the hole injection layer material HAT-CN is 5nm, and the hole injection layer is used as a hole injection layer;

3) evaporating a hole transport material NPB on the hole injection layer in a vacuum evaporation mode, wherein the thickness of the hole transport material NPB is 60nm, and the hole transport layer is used as a first hole transport layer;

4) evaporating a hole transport material compound 2 on the first hole transport layer NPB in a vacuum evaporation mode, wherein the thickness of the hole transport material compound 2 is 15nm, and the layer serves as a second hole transport layer;

5) co-evaporating a light-emitting layer on the second hole transport layer by a vacuum evaporation mode, wherein BH1 is used as a main material, BD01 is used as a light-emitting material, the doping amount ratio is 5%, and the thickness is 30 nm;

6) evaporating a hole blocking material TPBI on the light-emitting layer in a vacuum evaporation mode, wherein the thickness of the hole blocking material TPBI is 10nm, and the layer is used as a hole blocking layer;

7) evaporating an electron transport material ET-1 on the hole blocking layer in a vacuum evaporation mode, wherein the thickness of the electron transport material ET-1 is 35nm, and the electron transport material ET-1 serves as an electron transport layer;

8) evaporating an electron injection material Liq on the electron transport layer in a vacuum evaporation mode, wherein the thickness of the electron injection material Liq is 2nm, and the electron injection layer is used as an electron injection layer;

9) on the electron injection layer, a cathode Al was deposited by vacuum deposition to a thickness of 100nm, and the layer was used as a cathode conductive electrode.

The remaining prepared organic electroluminescent devices were the same as the organic electroluminescent device comprising compound 2, except that compound 3 was used as the second hole transport layer instead of compound 2; compound 5 as a second hole transport layer instead of compound 2; compound 11 as a second hole transport layer instead of compound 2; compound 40 as a second hole transport layer instead of compound 2; TCTA as the second hole transport layer, compound 4 as the light emitting material instead of BD 01; TCTA as the second hole transport layer, compound 6 as the light emitting material instead of BD 01; TCTA as the second hole transport layer, compound 13 as the light emitting material instead of BD 01; TCTA as the second hole transport layer, compound 16 as the light emitting material instead of BD 01; TCTA as the second hole transport layer, compound 18 as the light emitting material instead of BD 01; TCTA as the second hole transport layer and compound 29 as the light emitting material instead of BD 01; TCTA as the second hole transport layer, compound 34 as the light emitting material instead of BD 01; TCTA as the second hole transport layer and compound 48 as the light emitting material instead of BD 01; TCTA was used as the second hole transport layer, and compound 52 was used as the light emitting material instead of BD 01.

Based on the above-described preparation steps, the organic electroluminescent device constituent components of each device test group are shown in table 2.

TABLE 2 composition of organic electroluminescent devices of each group

(3) Performance testing of organic electroluminescent devices

The organic electroluminescent device prepared as described in (2) of example 2 was connected between the cathode and the anode using a driving circuit, and a Keithley2400 power supply in combination with a PR670 photometer by a standard methodTesting the voltage-efficiency-current density relation of the OLED device; the service life of the device is tested by a constant current method under the condition that the constant current density is 10mA/cm²The time for the test luminance to decay to 80% of the initial luminance is defined as the device LT₈₀The life and the test results are shown in Table 3.

TABLE 3 Performance results for each group of organic electroluminescent devices

As can be seen from Table 3, the compound provided by the invention is used as a second hole transport layer material or a luminescent material in an OLED blue light emitter, and has excellent performance. Compared with the comparative group 1TCTA, the compound 3 in the experimental group 2 as the second hole transport layer has obviously improved luminous efficiency and service life, the luminous efficiency is improved by 22 percent, and the service life is improved by 23.8 percent; compared with BD01, compound 34 in test group 12 has 26.5% higher luminous efficiency and 32.9% longer service life as a luminescent material. Compared with the prior art that the compound is applied to the OLED device, the compound provided by the invention has good photoelectric properties such as luminous efficiency, service life and the like, has a great application value in the application of the OLED device, and has a good industrial prospect.

As described above, the present invention can be preferably implemented, and the above-mentioned embodiments only describe the preferred embodiments of the present invention, and do not limit the scope of the present invention, and various changes and modifications of the technical solution of the present invention made by those skilled in the art without departing from the design spirit of the present invention shall fall within the protection scope defined by the present invention.