An organic composition for an organic electroluminescent device and an organic electroluminescent device comprising the same

Abstract

The application belongs to the technical field of OLED and specifically comprises an organic composition for an organic electroluminescent device and an organic electroluminescent device comprising the same. The organic composition comprises a first compound as a first hole transport layer material, a second compound as a second hole transport layer material and a third compound as an electron transport layer material; wherein the general structural formula of the first compound is shown as formula I, the general structural formula of the second compound is shown as formula II, and the general structural formula of the third compound is shown as formula III. The layer formed by the first compound and the layer formed by the second compound jointly constitute a hole transport region, which can match the hole mobility of the whole hole transport region with the electron mobility of the electron transport layer formed by the third compound, so that the transmission of holes and electrons to the light-emitting layer is more balanced, the carrier recombination probability of the light-emitting layer is improved, the device efficiency is improved, and the device voltage is reduced.I;II;III

Description

Technical Field

[0001] This invention belongs to the field of OLED technology, specifically including an organic composition for an organic electroluminescent device and an organic electroluminescent device containing the same. Background Technology

[0002] Organic light-emitting diodes (OLEDs), as a next-generation flat panel display technology, have become one of the hottest topics in the information display field due to their numerous advantages, including self-emission, low driving voltage, low power consumption, fast response speed, high color purity, simple fabrication process, wide viewing angle, rollability, and environmental friendliness. OLEDs can be applied in various fields such as televisions, smartphones, smart wearables, small displays, and indoor lighting. Currently, numerous electronics and chemical companies and institutions are investing significant human and financial resources in the research and development of OLED materials and products, making OLEDs and materials one of the most competitive cutting-edge scientific fields.

[0003] After years of development, light-emitting devices have made significant progress in performance and demonstrated enormous application potential. However, shortcomings still exist, such as the need for further improvement in photoelectric performance. Organic electroluminescent devices (OLEDs) consist of a cathode, an anode, and an organic functional layer between them. This organic functional layer can specifically include a hole injection layer, a hole transport layer, a light-emitting layer, an electron transport layer, and an electron injection layer, each containing different organic materials. The light-emitting principle is as follows: holes and electrons are injected from the anode and cathode of the device through the organic functional layer to the light-emitting layer. They recombine in the light-emitting region of the light-emitting layer to form excitons, which then release photons through radiative transitions, thus achieving light emission. However, due to the imbalance in hole and electron transport between the hole transport layer and the electron transport layer, the rate or quantity of holes and electrons reaching the light-emitting layer is mismatched, limiting the recombination probability and efficiency of holes and electrons. This is one of the reasons restricting the efficiency of existing organic electroluminescent devices. On the other hand, the compatibility between adjacent organic functional layer materials has a certain impact on the device voltage.

[0004] Therefore, developing an organic composition that can improve the efficiency of organic electroluminescent devices while reducing device voltage is an urgent problem to be solved. Summary of the Invention

[0005] In view of the above-mentioned problems in the prior art, the present invention provides an organic composition for an organic electroluminescent device and an organic electroluminescent device comprising the same.

[0006] To achieve the above objectives, the technical solution adopted by the present invention includes: A first aspect of the present invention provides an organic composition for an organic electroluminescent device, comprising a first compound as a first hole transport layer material, a second compound as a second hole transport layer material, and a third compound as an electron transport layer material; The general structural formula of the first compound is shown in Formula I: I; Y1 represents a ring structure formed by fusion with carbazole, which may or may not exist, and has a carbon number of C4-C8. m represents 0, 1, or 2; L1 represents phenylene; Ar1, Ar2, and Ar3 are each represented independently. , , , , , Any one of them, and Ar1, Ar2, and Ar3 are not all of them. ; The general structural formula of the second compound is shown in Formula II: II; R1 and R2 each independently represent methyl or phenyl, and R1 and R2 optionally form a ring structure through single bond or heteroatom fusion; for example, the ring structure is , wait; n represents 0 or 1; L2 represents phenylene; Ar4 indicates , , , Any one of them; Ar5 indicates or ; The general structural formula of the third compound is shown in Formula III: III; Ar6 to Ar 10 Each of the following can be independently represented: aryl group with substituted or unsubstituted carbon atoms (C6-C30), heteroaryl group with substituted or unsubstituted carbon atoms (C6-C30), or fused-ring aryl group with substituted or unsubstituted carbon atoms (C6-C30), wherein the C atoms on the ring can be arbitrarily substituted by N or O. k represents 0 or 1; L3 represents phenylene; Any one of the hydrogen atoms in the first, second, and third compounds can be replaced by deuterium.

[0007] Furthermore, Y1 represents any one of phenyl, naphthyl, and anthracene.

[0008] Furthermore, the first compound is selected from the structures shown below:

[0009]

[0010]

[0011]

[0012]

[0013]

[0014]

[0015]

[0016]

[0017]

[0018]

[0019]

[0020]

[0021]

[0022]

[0023]

[0024]

[0025]

[0026]

[0027]

[0028]

[0029]

[0030]

[0031]

[0032]

[0033]

[0034]

[0035]

[0036]

[0037]

[0038]

[0039]

[0040] .

[0041] Furthermore, the second compound is selected from the structures shown below:

[0042]

[0043]

[0044]

[0045]

[0046]

[0047]

[0048]

[0049]

[0050]

[0051]

[0052]

[0053]

[0054]

[0055]

[0056] .

[0057] Furthermore, the Ar6 to Ar 10 At least one of the ring structures contains a cyano group.

[0058] Furthermore, Ar6 to Ar9 each represent independently. , , , , , , , , , Any one of them; Where X represents S or O.

[0059] Furthermore, the Ar 10 express , , , , , , Any one of them; Where X represents S or O.

[0060] Furthermore, the third compound is selected from the structures shown below:

[0061]

[0062]

[0063]

[0064]

[0065]

[0066]

[0067]

[0068]

[0069]

[0070]

[0071]

[0072]

[0073]

[0074]

[0075]

[0076]

[0077] .

[0078] A second aspect of the present invention provides an organic electroluminescent device comprising an anode, a hole transport region, a light-emitting layer, an electron transport region, and a cathode sequentially disposed on a substrate; wherein the hole transport region comprises a first compound and a second compound in the organic composition as described above, and the electron transport region comprises a third compound in the organic composition as described above.

[0079] Furthermore, the hole transport region includes a first hole transport layer and a second hole transport layer, wherein the first hole transport layer includes a first compound in the organic composition as described above, and the second hole transport layer includes a second compound in the organic composition as described above.

[0080] Furthermore, the electron transport region includes an electron transport layer, which includes a third compound in the organic composition as described above.

[0081] Beneficial effects of this invention: This invention protects an organic composition for use in an organic electroluminescent device and an organic electroluminescent device comprising the same. The organic composition includes a first compound, a second compound, and a third compound. The layers formed by the first compound and the second compound together constitute a hole transport region, and the third compound forms an electron transport layer. By using the organic composition provided by this invention, the overall hole mobility of the hole transport region can be matched with the electron mobility of the electron transport layer formed by the third compound, resulting in a more balanced transport of the two types of charge carriers (holes and electrons) to the light-emitting layer. This improves the carrier recombination probability of the light-emitting layer, enhances device efficiency, and reduces device voltage.

[0082] In addition, the layers formed by the first compound and the layers formed by the second compound are closely bonded and their energy levels are matched. Specifically, the absolute value of the difference between their HOMO energy levels (ΔHOMO) is small, and there is no obvious potential barrier. Therefore, hole injection is easier at the interface between the adjacent layers formed by the two compounds. Together, they can be used as hole transport layers in organic electroluminescent devices to form energy level steps, which can reduce the operating voltage of organic electroluminescent devices. Attached Figure Description

[0083] Figure 1 This is a schematic diagram of the structure of the organic electroluminescent device of the present invention, wherein 1-substrate, 2-anode, 3-hole injection layer, 4-first hole transport layer, 5-second hole transport layer, 6-light-emitting auxiliary layer, 7-light-emitting layer, 8-hole blocking layer, 9-electron transport layer, 10-electron injection layer, 11-cathode, and 12-capping layer. Detailed Implementation

[0084] To better understand the content of this invention, a detailed description will be provided in conjunction with the accompanying drawings and embodiments.

[0085] The compounds of this invention are applicable to light-emitting elements, display panels, and electronic devices, particularly organic electroluminescent devices. The electronic devices described in this invention are devices comprising a layer of at least one organic compound, and may also comprise layers of inorganic materials or layers formed entirely of inorganic materials. Preferably, the electronic devices are organic electroluminescent devices (OLEDs), organic integrated circuits (O-ICs), organic field-effect transistors (O-FETs), organic thin-film transistors (O-TFTs), organic light-emitting transistors (O-LETs), organic solar cells (O-SCs), organic dye-sensitized solar cells (O-DSSCs), organic optical detectors, organic photosensors, organic field quenching devices (O-FQDs), light-emitting electrochemical cells (LECs), organic laser diodes (O-lasers), and organic plasma emitting devices. Organic electroluminescent devices (OLEDs) are particularly preferred. A schematic diagram of an exemplary organic electroluminescent device is shown below. Figure 1 As shown.

[0086] Experimental Section To better understand the content of this invention, the polycyclic compound, the preparation method of the compound, and the luminescent properties of the device will be explained in detail with reference to embodiments. Various chemical reactions can be applied to the synthesis method of the compound according to one embodiment of this invention. However, it should be noted that the synthesis method of the compound according to one embodiment of this invention is not limited to the synthesis method described below. Unless otherwise stated, subsequent synthesis is carried out in an anhydrous solvent under a protective gas atmosphere. Solvents and reagents can be purchased from conventional reagent suppliers.

[0087] Synthesis Example 1: Synthesis of Compound HTO4

[0088] In a round-bottom flask, starting compound 1-1 (10.00 g), starting compound 1-2 (20.50 g), K2CO3 (16.65 g), tetrahydrofuran (40 mL), and water (250 mL) were added sequentially. The solvent was removed by freeze-drying. Under nitrogen protection, Pd(PPh3)4 (1.00 g) was added, and the mixture was heated to reflux for 18 h. After the reaction was complete as detected by TLC, the mixture was allowed to cool naturally to room temperature. The solvent was removed by rotary evaporation. The residue was dissolved in 800 mL of dichloromethane, washed with 1000 mL of water, poured into a separatory funnel, shaken, and allowed to stand for separation. The aqueous phase was extracted three times with dichloromethane (750 mL). The organic phases were combined, dried with anhydrous magnesium sulfate, filtered, and the filtrate was rotary evaporated to remove dichloromethane to obtain the crude product. The crude product was purified by silica gel column chromatography to obtain intermediate compound 1-3 (19.02 g, 75% yield). [MS-ESI] + ]:638.27.

[0089] Starting compound 1-4 (4.75 g) and intermediate compound 1-3 (11.00 g) were added to dimethyl sulfoxide (200 mL), followed by potassium hydroxide (0.20 g). The mixture was stirred at 160 °C for 24 hours under reflux. The resulting mixture was purified by column chromatography to give compound HTO4 (4.9 g, yield 81%). [MS-ESI] + ]:830.37; 1 H NMR (500 MHz, DMSO-d6) δ 8.19 (s, 1H), 8.13 (s, 1H), 7.82 (d, 2H), 7.68 (s, 1H), 7.66 (d, 2H),7.64 (d, 3H), 7.62 (s, 5H), 7.61 (q, 3H), 7.59 (d, 2H), 7.48 (s, 1H), 7.47(s, 1H), 7.44 (d, 2H), 7.42 (d, 2H), 7.41 (t, 1H), 7.39-7.38 (m, 2H), 7.37(t, 1H), 7.35 (d, 2H), 7.34 (s, 1H), 7.26 (s, 1H), 7.16 (d, 3H), 7.15 (d, 3H), 1.55 (s, 6H). Synthesis Example 2: Synthesis of Compound HT11

[0090] The preparation method was the same as in Synthesis Example 1, except that compound 2-1 was used to replace compound 1-3, and compound 2-2 was used to replace compound 1-4, yielding compound HT11 (6.3 g, yield 84%). [MS-ESI] + ]:665.31; 1 H NMR (500MHz, DMSO-d6) δ 7.82 (s, 1H), 7.80 (s, 1H), 7.69 – 7.63 (m, 4H), 7.62-7.59(m, 3H), 7.56 – 7.51 (m, 5H), 7.50 (d, 1H), 7.47-7.44 (m, 2H), 7.44-7.40 (m,3H), 7.40-7.35 (m, 4H), 7.33 (d, 1H), 7.33-7.29 (m, 2H), 7.21-7.19 (m, 2H),7.18 (d, 2H), 7.15 (d, 1H), 7.09 (t, 1H), 1.55(s, 6H). Synthesis Example 3: Synthesis of Compound ET01

[0091] The preparation method was the same as in Synthesis Example 1, using a method similar to that used for preparing intermediate compounds 1-3, except that compound 1-2 was replaced by compound 3-2, and compound 1-1 was replaced by compound 3-1, yielding intermediate compound 3-3 in 78% yield. [MS-ESI] + ]:444.11.

[0092] Under nitrogen protection, intermediate compound 3-3 (6.60 g) and bis(pinacol)diboron (3.81 g) were added to 1,4-dioxane (150 mL) and stirred under reflux. Then, potassium acetate (9.63 g) was added, and after thorough stirring, bis(dibenzylacetone)palladium(0) (0.09 g) and dicyclohexylphosphine (0.06 g) were added. After reacting for 9 hours, the mixture was cooled to room temperature, the organic layer was filtered to remove salts, and the collected organic layer was concentrated by rotary evaporation. It was then dissolved in chloroform (250 mL), washed three times with water (300 mL), the organic layer was separated, dried over anhydrous magnesium sulfate, filtered, and the filtrate was distilled under reduced pressure. The concentrated compound was recrystallized from chloroform and ethanol to give intermediate compound 3-4 (4.77 g, yield 59%). [MS-ESI] + ]:536.24.

[0093] By using a method similar to that used in the preparation of intermediates 1-3, compounds 1-2 were replaced with compounds 3-4, and compounds 1-1 were replaced with compounds 3-5, to obtain compound ET01 (4.5 g, 71% yield). [MS-ESI] + ]:641.23. 1 H NMR(500 MHz, DMSO-d6) δ 8.28 (t, 4H), 8.27 (d, 4H), 8.03 (d, 1H), 7.89-7.84 (m,2H), 7.71 (d, 1H), 7.70 (d, 1H), 7.63 (d, 1H), 7.62 (d, 1H), 7.56-7.53 (m,2H), 7.53-7.51 (m, 2H), 7.50 (d, 3H), 7.49 (d, 4H), 7.48 (q, 1H). Synthesis Example 4: Synthesis of Compound ET02

[0094] The preparation method was the same as in Synthesis Example 3, using a method similar to that used for preparing intermediate compounds 1-3, but with compound 4-1 replacing compound 3-2 and compound 4-2 replacing compound 3-1, to obtain intermediate compound 4-3 in 86% yield. [MS-ESI] + ]:495.15.

[0095] Intermediate compound 4-4 was obtained by replacing compound 3-3 with compound 4-3 using a method similar to that used in the preparation of intermediate compound 3-4, with a yield of 62%. [MS-ESI] + ]:587.27.

[0096] By using a method similar to that used in the preparation of compound ET01, compound ET02 (4.4 g, yield 62%) was obtained by replacing compound 3-4 with compound 4-4 and compound 3-5 with compound 4-5. [MS-ESI] + ]:692.27. 1 H NMR (500MHz, DMSO-d6) δ 8.28 (t, 4H), 8.27 (dd, 4H), 8.07 (t, 1H), 8.03 (q, J = 2.2Hz, 2H), 8.00 (t, 1H), 7.83 (dt, 1H), 7.68-7.65 (m, 1H), 7.65-7.63 (m, 2H), 7.56-7.53 (m, 2H), 7.53 – 7.50 (m, 6H), 7.50 – 7.47 (m, 5H), 7.45-7.41 (m, 2H), 7.40-7.35 (m, 1H). Synthesis Example 5: Synthesis of Compound HT06

[0097] The preparation method was the same as in Synthesis Example 1, except that compound 5-1 replaced compound 1-3, and compound 5-2 replaced compound 1-4, to obtain compound HT06 (4.63 g, yield 86%). [MS-ESI] + ]:802.33. 1H NMR (500 MHz, DMSO-d6) δ 8.20 (s, 1H), 7.93 (s, 1H), 7.80 (s, 1H), 7.70 (d, 2H), 7.69 (d, 2H),7.67 (s, 1H), 7.62 (d, 5H), 7.61 (d, 1H), 7.59 (d, 1H), 7.47 (s, 1H), 7.45-7.41 (m, 3H), 7.41-7.37 (m, 5H), 7.38-7.35 (m, 4H), 7.34-7.30 (m, 2H), 7.27-7.22 (m, 3H), 7.22-7.20 (m, 2H), 7.19 (t, 1H), 7.09 (tt, 1H), 7.03 (t, 2H), 7.02 (q, 3H). Synthesis Example 6: Synthesis of Compound HT07

[0098] The preparation method was the same as in Synthesis Example 1, except that compound 6-1 replaced compound 1-3, and compound 6-2 replaced compound 1-4, to obtain compound HT07 (5.12 g, yield 83%). [MS-ESI] + ]:804.35. 1 H NMR (500 MHz, DMSO-d6) δ 8.21 (s, 1H), 8.20 (s, 1H), 8.05 (s, 1H), 7.94 (s, 1H), 7.87 (s, 1H),7.82 (s, 1H), 7.75 (s, 1H), 7.70 (s, 2H), 7.69 (d, 1H), 7.67 (s, 2H), 7.62(d, 5H), 7.62-7.60 (m, 2H), 7.60 (q, 2H), 7.51 (s, 2H), 7.47 (s, 1H), 7.45-7.41 (m, 2H), 7.41-7.39 (m, 1H), 7.39-7.36 (m, 4H), 7.35 (s, 1H), 7.34 (s,1H), 7.26 (s, 1H), 7.17-7.15 (m, 2H), 7.01 (s, 1H), 1.54 (s, 6H). Synthesis Example 7: Synthesis of Compound HT08

[0099] The preparation method was the same as in Synthesis Example 1, except that compound 7-1 replaced compound 1-3, and compound 7-2 replaced compound 1-4, to obtain compound HT08 (4.19 g, yield 79%). [MS-ESI] + ]:804.35. 1 H NMR (500 MHz, DMSO-d6) δ 8.21 (s, 1H), 8.20 (s, 1H), 8.05 (s, 1H), 7.94 (s, 1H), 7.87 (s, 1H),7.82 (s, 1H), 7.75 (s, 1H), 7.70 (s, 1H), 7.67 (s, 2H), 7.66 (d, 1H), 7.66-7.64 (m, 2H), 7.64 (d, 1H), 7.62 (d, 5H), 7.61-7.58 (m, 2H), 7.51 (s, 2H),7.47 (s, 1H), 7.45-7.41 (m, 2H), 7.40 (d, 1H), 7.39-7.37 (m, 4H), 7.35 (s,1H), 7.34 (s, 1H), 7.26 (s, 1H), 7.21 (s, 1H), 7.16 (d, 1H), 7.15 (d, 1H),7.01 (s, 1H), 1.54 (s, 6H). Synthesis Example 8: Synthesis of Compound HT09

[0100] The preparation method was the same as in Synthesis Example 1, except that compound 1-3 was replaced by compound 8-1 and compound 1-4 was replaced by compound 8-2, yielding compound HT09 (5.50 g, yield 77%). [MS-ESI] + ]:799.42. 1H NMR (500 MHz, DMSO-d6) δ 7.82 (s, 1H), 7.80 (s, 1H), 7.68-7.66 (m, 2H), 7.66-7.64 (m, 2H), 7.61(d, 2H), 7.60 (d, 1H), 7.55 (t, 1H), 7.55-7.52 (m, 3H), 7.52-7.50 (m, 2H),7.47 (d, 1H), 7.46-7.43 (m, 1H), 7.42 (dd, 1H), 7.41-7.39 (m, 2H), 7.40-7.35(m, 4H), 7.19 (d, 1H), 7.18 (d, 1H), 7.15 (d, 1H), 7.13 (d, 1H), 7.11 (d,1H), 7.04 (d, 1H), 7.03 (d, 1H), 3.42 (d, 3H), 2.10 (s, 3H), 1.92 (s, 6H),1.83 (d, 3H), 1.54 (s, 6H). Synthesis Example 9: Synthesis of Compound HT10

[0101] The preparation method was the same as in Synthesis Example 1, except that compound 9-1 replaced compound 1-3, and compound 9-2 replaced compound 1-4, yielding compound HT10 (4.88 g, 91%). [MS-ESI] + ]:723.39. 1 H NMR (500 MHz, DMSO-d6)δ 8.02 (t, 1H), 7.82 (s, 1H), 7.67 (s, 1H), 7.66-7.64 (m, 2H), 7.64-7.61 (m,2H), 7.55 (q, 1H), 7.55-7.52 (m, 3H), 7.50 (t, 1H), 7.47 (s, 1H), 7.45-7.42(m, 2H), 7.42-7.41 (m, 2H), 7.38 (q, 4H), 7.36 (dt, 1H), 7.08-7.05 (m, 2H),7.05-7.02 (m, 2H), 7.01 (s, 1H), 3.42 (d, 3H), 2.10 (s, 3H), 1.92 (s, 6H), 1.83 (d, 3H), 1.54 (s, 6H). Synthesis Example 10: Synthesis of Compound HT12

[0102] The preparation method was the same as in Synthesis Example 1, except that compound 1-3 was replaced with compound 10-1 and compound 1-4 was replaced with compound 10-2, yielding compound HT12 (5.13 g, 75% yield). [MS-ESI] + ]:727.29. 1 H NMR (500 MHz, DMSO-d6) δ 8.01 (s, 1H), 7.74 (s, 1H), 7.66 (dt, 3H), 7.60 (s, 1H), 7.55 (q,1H), 7.54-7.52 (m, 3H), 7.53-7.50 (m, 2H), 7.51-7.49 (m, 1H), 7.46 (dd, 1H),7.44-7.40 (m, 4H), 7.40 (q, 3H), 7.39-7.36 (m, 3H), 7.35-7.33 (m, 1H), 7.33-7.28 (m, 3H), 7.22 (td, 2H), 7.20-7.16 (m, 2H), 7.15 (d, 1H), 7.13 (s, 1H), 7.12-7.07 (m, 3H). Synthesis Example 11: Synthesis of Compound HT13

[0103] The preparation method was the same as in Synthesis Example 1, except that compound 1-1 was used to replace compound 1-3, and compound 1-2 was used to replace compound 1-4, yielding compound HT13 (4.69 g, yield 84%). [MS-ESI] + ]:892.38. 1H NMR (500 MHz, DMSO-d6) δ 8.20 (s, 1H), 7.84 (s, 1H), 7.71 (s, 1H), 7.68 – 7.64 (m, 7H), 7.62 – 7.61 (m, 2H), 7.60 (s, 1H), 7.55 (dq, 1H), 7.54 – 7.52 (m, 3H), 7.51(dd, 2H), 7.49 – 7.46 (m, 2H), 7.46 – 7.44 (m, 2H), 7.44 – 7.41 (m, 2H), 7.40(dd, 2H), 7.38 (d, 4H), 7.38 – 7.37 (m, 2H), 7.35 (s, 1H), 7.34 (s, 1H), 7.34– 7.31 (m, 1H), 7.31 – 7.29 (m, 1H), 7.26 (s, 1H), 7.26 – 7.22 (m, 1H), 7.19(d, 1H), 7.18 (d, 1H), 7.16 – 7.14 (m, 2H), 7.14 (d, 2H), 1.71 (s, 3H). Synthesis Example 12: Synthesis of Compound HT14

[0104] The preparation method was the same as in Synthesis Example 1, except that compound 1-3 was replaced by compound 12-1 and compound 1-4 was replaced by compound 12-2, yielding compound HT14 (5.24 g, 74% yield). [MS-ESI] + ]:865.37. 1H NMR (500 MHz, DMSO-d6) δ 8.30 (s, 1H), 7.95 (s, 1H), 7.93 (s, 1H), 7.68 – 7.66 (m, 4H), 7.66 – 7.64 (m, 2H), 7.61 (q, 2H), 7.60 – 7.58 (m, 2H), 7.56 – 7.54 (m, 2H), 7.53 (dd, 2H), 7.51 (dd, 2H), 7.47 (s, 1H), 7.44 (dd, 1H), 7.44 – 7.41 (m,5H), 7.41 – 7.39 (m, 3H), 7.39 – 7.37 (m, 5H), 7.36 (d, 2H), 7.27 – 7.22 (m,2H), 7.20 (d, 2H), 7.18 (d, 2H), 7.15 (d, 1H), 7.03 (t, 2H), 7.02 (t, 2H). Synthesis Example 13: Synthesis of Compound HT15

[0105] The preparation method was the same as in Synthesis Example 1, except that compound 1-3 was replaced by compound 13-1 and compound 1-4 was replaced by compound 13-2, yielding compound HT15 (4.00 g, yield 73%). [MS-ESI] + ]:863.36. 1 H NMR (500 MHz, DMSO-d6) δ 8.18 (s, 1H), 8.02 (t, 1H), 7.97 (s, 1H), 7.95 (s, 3H), 7.67 (s,1H), 7.66 – 7.64 (m, 2H), 7.64 – 7.62 (m, 2H), 7.61 (dd, 3H), 7.56 – 7.54 (m,2H), 7.54 – 7.52 (m, 2H), 7.50 (d, 4H), 7.49 (d, 1H), 7.48 (t, 1H), 7.45 –7.42 (m, 2H), 7.42 – 7.40 (m, 5H), 7.40 – 7.39 (m, 2H), 7.38 (d, 5H), 7.38 –7.36 (m, 2H), 7.36 – 7.33 (m, 1H), 7.26 (dd, 1H), 7.24 – 7.22 (m, 1H), 7.19(d, 1H), 7.18 (d, 1H). Synthesis Example 14: Synthesis of Compound HT16

[0106] The preparation method was the same as in Synthesis Example 1, except that compound 1-3 was replaced by compound 14-1 and compound 1-4 was replaced by compound 14-2, yielding compound HT16 (5.92 g, 86%). [MS-ESI] + ]:861.43. 1 H NMR (500 MHz, DMSO-d6) δ 7.84 (s, 1H), 7.68-7.63 (m, 6H), 7.62-7.58 (m, 2H), 7.55 (dd, 1H), 7.54-7.52 (m, 3H), 7.52-7.49 (m, 2H), 7.47-7.44 (m, 2H), 7.44-7.41 (m, 2H), 7.41-7.37 (m, 5H), 7.34 (s, 1H), 7.33-7.29 (m, 2H), 7.27-7.22 (m, 1H), 7.19(d, 1H), 7.18 (d, 1H), 7.17-7.13 (m, 3H), 7.13 (d, 1H), 7.11 (d, 1H), 7.04(s, 1H), 7.04-7.02 (m, 1H), 3.42 (d, 3H), 2.09 (s, 3H), 1.92 (s, 6H), 1.83(d, 3H), 1.54 (s, 6H). Synthesis Example 15: Synthesis of Compound ET03

[0107] The preparation method was the same as in Synthesis Example 1, except that compound 1-3 was replaced by compound 15-1 and compound 1-4 was replaced by compound 15-2, yielding compound ET03 (3.37 g, yield 48%). [MS-ESI] + ]:869.33. 1H NMR (500 MHz, DMSO-d6) δ 8.30-8.27 (m, 3H), 8.27 (dd, 2H), 8.09 (d, 2H), 7.93 (d, 2H), 7.92(d, 2H), 7.72-7.70 (m, 1H), 7.70-7.67 (m, 5H), 7.67-7.64 (m, 2H), 7.61 (q,2H), 7.60-7.58 (m, 2H), 7.54 (dd, 3H), 7.52 (p, 1H), 7.51-7.49 (m, 4H), 7.49-7.46 (m, 2H), 7.44 (t, 1H), 7.42 (d, 2H), 7.41 (t, 1H), 7.39 (q, 1H), 7.38-7.35 (m, 1H). Other structurally similar compounds can be prepared according to the preparation methods disclosed in this invention and the prior art.

[0108] Synthesis Example 16: Synthesis of Compound HT01

[0109] The preparation method was the same as in Synthesis Example 1, except that compound 1-3 was replaced by compound 16-1 and compound 1-4 was replaced by compound 16-2, to obtain compound HT01 with a yield of 88%.

[0110] Synthesis Example 17: Synthesis of Compound HTO2

[0111] The preparation method was the same as in Synthesis Example 1, except that compound 1-3 was replaced by compound 17-1 and compound 1-4 was replaced by compound 17-2, to obtain compound HTO2 with a yield of 83%.

[0112] Synthesis Example 18: Synthesis of Compound HTO3

[0113] The preparation method was the same as in Synthesis Example 1, except that compound 1-3 was replaced by compound 18-1 and compound 1-4 was replaced by compound 18-2, to obtain compound HTO3 with a yield of 87%.

[0114] Synthesis Example 19: Synthesis of Compound HT05

[0115] The preparation method was the same as in Synthesis Example 1, except that compound 1-3 was replaced by compound 19-1 and compound 1-4 was replaced by compound 19-2, to obtain compound HT05 with a yield of 78%.

[0116] Synthesis Example 20: Synthesis of Compound ET04

[0117] The preparation method was the same as in Synthesis Example 1, except that compound 1-3 was replaced by compound 20-1 and compound 1-4 was replaced by compound 20-2, to obtain compound ET04 with a yield of 51%.

[0118] Synthesis Example 21: Synthesis of Compound ET05

[0119] The preparation method was the same as in Synthesis Example 1, except that compound 1-3 was replaced by compound 21-1 and compound 1-4 was replaced by compound 21-2, to obtain compound ET05 with a yield of 54%.

[0120] Comparative compounds DHT1, DHT2, DHT3, DHT4, DET1 DET2.

[0121] Material performance evaluation The compounds prepared in the synthesis examples of this invention and the comparative compounds were tested as follows: HOMO level: Tested using the ionization energy testing system (IPS3) in a vacuum environment. The absolute value of the difference between the HOMO value of the first compound (denoted as HOMO1) and the HOMO value of the second compound (denoted as HOMO2) is defined as ΔHOMO. 12 (i.e. │HOMO1-HOMO2│) <0.1 (eV); Eg level: Tested using a double-beam UV-Vis spectrophotometer (model: TU-1901). The value is calculated by drawing a tangent between the UV spectrophotometric (UV absorption) baseline of the single film of the material and the rising side of the first absorption peak, and using the value of the intersection of the tangent and the baseline. Hole mobility / electron mobility: Measured using the space charge confined current method (SCLC) after fabricating a single-charged half-device from the composite material. Hole mobility μ is measured. hIn this invention, the first and second compounds in the composition each form two adjacent layers that together constitute the hole transport region. MnO2 is used as the hole injection layer to regulate the potential barrier, thus fabricating a HOD device. Electron mobility μ is measured. e An electron transport layer is prepared using the third compound in the composition of this invention, and an EOD device is fabricated by controlling the potential barrier using LiF as an electron injection layer. The carrier transport balance coefficient k for organic electroluminescent devices is defined. DB = 10μ h / μ e k DB The closer k is to 1, the better the transport of holes and electrons is matched in this pairing. DB A score less than 10 indicates a good balance.

[0122] The general formula for a single-charge semiconductor device is as follows: Hole transport side HOD: ITO│MnO2 (5nm)│First compound: F4TCNQ (97:3, 10nm)│First compound (65nm)│Second compound (50nm)│Al Electron transport side EOD: Al│LiF (1 nm)│Third compound:LiQ (1:1, 30 nm)│LiF (1 nm)│Al All semiconductor devices were deposited with compound layers via vacuum evaporation. Before vacuum evaporation, the substrate was cleaned with a cleaning agent and deionized water in an ultrasonic bath for 20 minutes, then dried in an oven at 120°C, and finally pretreated with UV to obtain a clean substrate. The results are shown in Table 1.

[0123] Table 1

[0124] As can be seen, compared to Comparative Examples 1-7, the compounds used in Effect Examples 1-12, when combined with organic electroluminescent devices, exhibit a carrier transport balance coefficient k that is closer to 1. DB This demonstrates that using the compounds of the present invention to prepare organic electroluminescent devices results in a more balanced carrier transport compared to the comparative example, which is beneficial for reducing voltage and improving luminous efficiency.

[0125] Furthermore, the absolute value ΔHOMO of the difference between the HOMO value of the first compound and the HOMO value of the second compound in Examples 1 to 12 of the present invention is... 12 <0.1 (eV); while in Comparative Examples 1, 2, 4 to 7, ΔHOMO 12>0.1 (eV), therefore, the first and second compounds in this invention, when used together as the hole transport region in organic electroluminescent devices, can form an energy level ladder, thereby reducing the voltage. Comparative Example 3 uses the same first and second compounds as in this invention to form the hole transport region, only changing the choice of the third compound as the electron transport layer material; therefore, ΔHOMO... 12 There was no change, but due to the use of different compounds in the electron transport layer material, the carrier transport balance coefficient k was affected. DB A significant increase in size is detrimental to reducing device voltage and improving luminous efficiency.

[0126] OLED manufacturing and characterization The electrode fabrication method and the deposition method of each functional layer in this embodiment are conventional methods in the art, such as vacuum thermal evaporation or inkjet printing, and will not be described in detail here. Only some process details and testing methods in the fabrication process are supplemented as follows: Device Example 1 This embodiment provides an organic electroluminescent device, the specific preparation method of which is as follows: Substrate 1 is subjected to the following operations: The ITO / Ag / ITO substrate is patterned to give it a light-emitting area of ​​3mm × 3mm, followed by ultrasonic treatment with water / isopropanol, UV / ozone irradiation, and then drying at 100°C. The ITO substrate is then mounted on the substrate support of the vacuum deposition apparatus, and the pressure is adjusted to achieve a vacuum rate of 1 × 10⁻⁶. -7 torr.

[0127] Then proceed as follows: First, a hole injection layer is formed on the ITO layer anode formed on substrate 1 by vacuum deposition of compound first compound HT01 and compound PD01 (mass ratio of compound HT01 to compound PD01 is 97:3) with a thickness of 10 nm. On the aforementioned hole injection layer, a first hole transport layer is formed by vacuum deposition of compound HT01 with a thickness of 65 nm. On the first hole transport layer mentioned above, a second hole transport layer is formed by vacuum deposition of compound HT09 with a thickness of 50 nm. On the aforementioned second hole transport layer, a light-emitting auxiliary layer is formed by vacuum deposition of compound BPO1 with a thickness of 5 nm; On the aforementioned light-emitting auxiliary layer, a mixture of compound BH01 and compound BD01 is vacuum-deposited to a thickness of 20 nm to form a light-emitting layer, wherein compound BH01 is used as the host material and compound BD01 is used as the guest material, and the mass ratio of the host material to the guest material is 98:2. On the aforementioned light-emitting layer, a hole-blocking layer is formed by vacuum deposition of compound HB with a thickness of 5 nm; On the aforementioned hole blocking layer, an electron transport layer is formed by vacuum depositing compound ET01 and compound LiQ (the mass ratio of compound ET01 to compound LiQ is 1:1) with a thickness of 30 nm. On the aforementioned electron transport layer, an electron injection layer is formed by vacuum deposition of Yb with a thickness of 1 nm; On the aforementioned electron injection layer, Mg and Ag (Mg to Ag mass ratio of 1:9) are deposited to form a cathode with a thickness of 15 nm; On the aforementioned cathode, a capping layer of compound CP01 with a thickness of 50 nm is deposited to form a capping layer; The vapor-deposited substrate is encapsulated, and a UV adhesive is applied to the cleaned cover plate using a coating equipment. The coated cover plate is then moved to the lamination section, where the vapor-deposited substrate is placed on top of the cover plate. Finally, the substrate and cover plate are bonded together using a bonding equipment, while simultaneously curing the UV adhesive under light, thus fabricating a top-emitting organic light-emitting device. The device structure is described in [reference needed]. Figure 1 .

[0128] Except for compounds HT01, HT09, and ET01, the molecular structures of the remaining layers are as follows:

[0129]

[0130] Device Examples 2-12 Using the above method, the compounds in other device examples in Table 2 are combined, and the first, second and third compounds are used to replace HT01, HT09 and ET01 in device example 1, respectively, to make organic electroluminescent devices. The specific material combinations are shown in Table 2.

[0131] Device Comparison Examples 1-7 Using the above method, the compounds in the other device comparison examples in Table 2 are combined, and the first, second and third compounds are used to replace HT01, HT09 and ET01 in device example 1, respectively, to make organic electroluminescent devices. The specific material combinations are shown in Table 2.

[0132] The OLED devices prepared in Examples 1-12 and Comparative Examples 1-7 were tested using standard methods. For this purpose, J = 10 mA / cm² was used. 2 The driving voltage and luminous efficiency of organic electroluminescent devices were determined under a given current density.

[0133] The testing instruments and methods used to perform performance tests on the above-mentioned device embodiments and device comparison examples are as follows: Current density and turn-on voltage: tested using a Keithley 2400 digital source meter; Luminous efficacy (CE) (cd / A) and chromaticity coordinates (CIEy) were measured using a PhotoResearch PR-655 spectral scanner. The luminous efficiency of blue light devices is greatly affected by chromaticity. The industry generally uses the BI value as the basis for the efficiency of blue light devices. BI (Blue index) is obtained by dividing the luminous efficiency CE (cd / A) by the chromaticity coordinate (CIEy).

[0134] The performance test results of the above devices are listed in Table 2.

[0135] Table 2

[0136] As shown in Table 2, the device performance test results reveal that in Comparative Examples 1, 2, and 4-6, different compounds from the first, second, or third compound of this invention were used. Due to carrier transport imbalance, the luminous efficiency of the devices decreased significantly, and the voltage increased. Furthermore, when using compounds different from the first or second compound of this invention, the device voltage increased further due to the larger energy level barrier. Comparative Example 3 only replaced the third compound in the electron transport layer. It can be seen that the efficiency decreased and the voltage increased due to carrier transport imbalance, but the voltage increase was not significant because the energy level difference of the first and second compounds was appropriate. Comparative Example 7 used compounds different from those of this invention, thus exhibiting the highest voltage and the lowest efficiency. In summary, compared with the comparative compounds, using the compound combination provided by this invention as both hole transport material and electron transport material significantly reduced the driving voltage and significantly improved the luminous efficiency of the prepared organic electroluminescent devices. This indicates that the composition provided by this invention is a high-performance transport material combination that can meet the performance requirements of organic electroluminescent devices and has practical value.

[0137] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. For those skilled in the art, other variations or modifications can be made based on the above description. It is impossible to exhaustively list all the implementation methods here. All obvious variations or modifications derived from the technical solutions of the present invention are still within the protection scope of the present invention.

Claims

1. An organic composition for use in organic electroluminescent devices, characterized in that, This includes a first compound as a first hole transport layer material, a second compound as a second hole transport layer material, and a third compound as an electron transport layer material; The general structural formula of the first compound is shown in Formula I: I； Y1 represents a ring structure formed by fusion with carbazole, which may or may not exist, and has a carbon number of C4-C8. m represents 0, 1, or 2; L1 represents phenylene; Ar1, Ar2, and Ar3 are each represented independently. , , , , , Any one of them, and Ar1, Ar2, and Ar3 are not all of them. ; The general structural formula of the second compound is shown in Formula II: II; R1 and R2 each independently represent methyl or phenyl, and R1 and R2 optionally form a ring structure by single bond or heteroatom fusion; n represents 0 or 1; L2 represents phenylene; Ar4 indicates , , , Any one of them; Ar5 indicates or ; The general structural formula of the third compound is shown in Formula III: III; Ar6 to Ar 10 Each of the following can be independently represented: aryl group with substituted or unsubstituted carbon atoms (C6-C30), heteroaryl group with substituted or unsubstituted carbon atoms (C6-C30), or fused-ring aryl group with substituted or unsubstituted carbon atoms (C6-C30), wherein the C atoms on the ring can be arbitrarily substituted by N or O. k represents 0 or 1; L3 represents phenylene; Any one of the hydrogen atoms in the first, second, and third compounds can be replaced by deuterium.

2. The organic composition according to claim 1, characterized in that, The first compound is selected from the structures shown below: 。 3. The organic composition according to claim 1, characterized in that, The second compound is selected from the structure shown below: 。 4. The organic composition according to claim 1, characterized in that, The Ar6 to Ar 10 At least one of the ring structures contains a cyano group.

5. The organic composition according to claim 1, characterized in that, Ar6 to Ar9 are each represented independently. , , , , , , , , , Any one of them; Where X represents S or O.

6. The organic composition according to claim 1, characterized in that, The Ar 10 express , , , , , , Any one of them; Where X represents S or O.

7. The organic composition according to claim 1, characterized in that, The third compound is selected from the following structures: 。 8. An organic electroluminescent device, characterized in that, The device comprises an anode, a hole transport region, a light-emitting layer, an electron transport region, and a cathode sequentially disposed on a substrate; wherein the hole transport region comprises a first compound and a second compound in the organic composition according to any one of claims 1 to 7, and the electron transport region comprises a third compound in the organic composition according to any one of claims 1 to 7.

9. The organic electroluminescent device according to claim 8, characterized in that, The hole transport region includes a first hole transport layer and a second hole transport layer, wherein the first hole transport layer includes a first compound in the organic composition according to any one of claims 1 to 7, and the second hole transport layer includes a second compound in the organic composition according to any one of claims 1 to 7.

10. The organic electroluminescent device according to claim 8, characterized in that, The electron transport region includes an electron transport layer, which includes a third compound in the organic composition according to any one of claims 1 to 7.

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