WO2024060203A1 - Organic hole injection material and use - Google Patents

Abstract

The present invention relates to the field of organic light emission, and particularly, to an organic hole injection material and use. The organic hole injection material is a double five-membered ring derivative substituted by an electron-deficient group, and a double five-membered ring includes, but is not limited to, a double five-membered ring composed of thiophene, furan or selenophene groups. The synthesis of the material is simple, and large-scale production is facilitated. HOMO and LUMO energy level structures of the material are appropriate, thereby facilitating the injection of carriers. The material takes a substituent group and the double five-membered ring as a core, such that transmission of carriers in a device is facilitated. The material has a high LUMO/HOMO energy level, such that holes can be easily transmitted from an anode ITO to a hole transport layer. An organic light-emitting diode prepared from the described hole injection layer material is used and has relatively high light-emitting efficiency and device service life, can improve the photoelectric conversion efficiency when being applied to a perovskite solar cell, and has relatively high commercial value.

Description

An organic hole injection material and its application Technical field

The invention relates to the field of organic light emitting, and in particular to an organic hole injection material and its application.

Background technique

Organic Light-emitting Diodes (OLEDs), as a new generation of display technology, have gradually become an important part of current display technology due to their many advantages such as self-illumination, flexibility, high contrast, and power saving, and have received academic attention. wide attention from the world and industry. In OLEDs devices, the hole injection layer serves as the key material connecting the anode and the organic functional layer. It can lower the barrier for hole injection from the anode, allowing holes to be efficiently injected from the anode into the OLED device. Therefore, when selecting the hole injection layer material, it is necessary to consider the matching of the material energy level and the anode material.

The function of the injection layer is to make a good match between the work function of the anode and the HOMO of the hole transport layer material, so that holes can flow smoothly from the electrode to the transport layer. In fact, through the OLED structure design, the luminescent material The highest occupied orbital energy level is close to the work function of the anode, lowering the hole injection energy barrier. A hole injection layer is usually added between the anode and the hole transport layer, mainly because the energy barrier between the anode and the hole transport layer is large, which will cause the driving voltage of the component to increase, indirectly causing The life of the component is shortened, so a layer of material whose HOMO energy level is between the anode and the hole transport layer is added to improve the efficiency between the hole injection and the hole transport layer. Currently, hole injection materials used in optoelectronic devices can be divided into two categories: inorganic hole injection materials and organic hole injection materials. Inorganic hole injection materials easily react with organic layers at high temperatures, and the high evaporation temperature of inorganic hole injection materials is not conducive to the preparation of organic optoelectronic devices. Organic hole injection materials can be divided into small molecule hole injection materials and polymer hole injection materials. Polymer hole injection materials are also very limited due to their purity and the inability to prepare devices by evaporation. Small molecule organic hole injection materials can produce very high-purity materials and can produce high-quality devices through evaporation methods. However, there are relatively few small molecules with suitable HOMO and LUMO energy levels, and the selection range is small. Therefore, it is necessary to develop new suitable organic small molecule hole injection materials. Developing suitable hole injection materials plays an important role in improving the device performance of OLEDs.

Contents of the invention

In view of the above shortcomings of existing hole injection materials, the present invention provides an organic hole injection material and its application.

The technical solution of the present invention is achieved in the following manner: an organic hole injection material is provided, the general structural formula of which is as follows:

wherein X, Y, and Z are each independently selected from C, O, CO, S, Se, SO, SeO, SO ₂ or SeO ₂ ;

At least one of R ₁ , R ₂ , R ₃ and R ₄ is selected from F, CN,

or

The remainder is hydrogen.

Preferably, in one embodiment of the present invention, in the general structural formula of the organic hole injection material, Y or Z are different, and one of Y or Z is C.

Preferably, in one embodiment of the invention,

When Y=C, its general structural formula is:

When Z=C, its general structural formula is:

Preferably, in one embodiment of the present invention, at least two of R ₁ , R ₂ , R ₃ and R ₄ are selected from F, CN,

or

The same or different from each other.

Preferably, in one embodiment of the present invention, some or all of the hydrogens in the molecular formula are replaced by deuterium.

Preferably, in one embodiment of the present invention, the organic hole injection material is represented by any one of the following compounds:

The invention also provides an organic light-emitting device based on a double five-membered ring derivative substituted by a fluorine atom or a cyano group or a pentafluorophenyl group as a hole injection layer material. The double five-membered ring is selected from thiophene, furan or selenophene double five-membered ring groups. The specific structure of the device is a transparent substrate, anode, hole injection layer, hole transport layer, electron blocking layer, light emitting layer, electron transport layer and cathode.

The transparent substrate can be glass or plastic.

Anode materials are inorganic materials such as indium tin oxide, zinc oxide, tin zinc oxide, etc.;

The material of the hole injection layer can be any one of the above general formulas;

The hole transport layer material can be any of the following:

The electron blocking layer material can be

The guest material in the light emitting layer can be BPH.

The hole blocking layer material can be any of the following:

The electron transport layer material can be any of the following:

The electron injection layer can be lithium fluoride, Liq, etc.

The cathode material is metal aluminum, magnesium silver alloy, etc.

The present invention also provides a perovskite solar cell, which includes a cathode, an anode and each organic layer; wherein, the hole injection layer uses any one of the aforementioned organic hole injection materials.

The beneficial effects are as follows: The hole injection material provided by the present invention is a double five-membered ring derivative substituted by an electron-deficient group. The double five-membered ring includes but is not limited to thiophene, furan or selenium phenol double five-membered ring group. . The synthesis of this type of material is relatively simple and is conducive to large-scale production; the HOMO and LUMO energy level structure of the material is suitable, which is conducive to the injection of carriers; the material has substituents and five-membered rings as the core, which is conducive to the transfer of carriers in the device Medium transmission; the material has a high LUMO/HOMO energy level, which is beneficial to transporting holes from the anode ITO to the hole transport layer.

It can be seen from the results of HOMO and LUMO of the test materials that the material has a suitable energy level structure and can be used as a hole injection layer material for organic light-emitting devices.

The organic light-emitting diode prepared by the present invention using the above hole injection layer material has high luminous efficiency and device life. When applied to perovskite solar cells, it can improve the photoelectric conversion efficiency and has high commercial value.

Description of drawings

FIG1 is a schematic diagram of the structure of an organic light-emitting device according to an embodiment of the present invention;

Figure 2 is a schematic structural diagram of a perovskite solar cell using one embodiment of the present invention.

Detailed ways

In order to make the purpose, technical solutions and advantages of the present invention more clear, the technical solutions of the present invention will be clearly and completely described below with reference to specific embodiments of the present invention and corresponding drawings. Obviously, the described embodiments are only some of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the scope of protection of the present invention.

The present invention will be described in further detail below with reference to the accompanying drawings and examples. If no specific experimental steps or conditions are specified in the examples, conventional experimental steps or conditions described in literature in the field can be followed. If the manufacturer of the reagents or instruments used is not indicated, they are all conventional products that are commercially available.

The compounds whose synthesis methods are not mentioned in the present invention are all raw material products obtained through commercial channels. The solvents and reagents used in the present invention can be purchased from the domestic chemical market. In addition, those skilled in the art can also synthesize them through known methods.

Example 1

The synthetic route of molecular formula 8 is as follows:

The synthesis method of the compound specifically includes the following steps:

Synthesis of intermediate M8: A chloroform solution (50 mL) containing liquid bromine (30 mL, 583 mmol) was added dropwise to a chloroform solution (50 mL) of thieno[3,2-b]thiophene (14.02 g, 100 mmol) at 0°C. , the dripping is completed within 4 hours. After the dropwise addition was completed, the reaction was heated to room temperature, and then stirred under reflux for 3 h. Afterwards, a saturated NaOH aqueous solution was added to the reactant, and the above mixture was stirred under reflux for 1 h to remove excess bromine. Extract with chloroform, extract the aqueous phase three times with 100 mL of dichloromethane, combine the organic phases, dry over anhydrous magnesium sulfate, condense the organic solution under reduced pressure, and remove from the 1:1 (v/v) solution of chloroform and ethanol. The crude solid was recrystallized to give product M8 (43.30 g, 95% yield). ¹³ C NMR (100MHz, Chloroform-d) δ 138.67, 107.85, 102.59.HRMS: [C ₆ HBr ₄ S ₂ ] ⁺ calculated: 452.6253, found: 452.6250.

Synthesis of Molecular Formula 8: Weigh M8 (22.79 g, 50 mmol), cuprous cyanide (9.85 g, 110 mmol) and DMF (100 mL) in a 500 mL round-bottom flask and stir at 140°C for 24 hours. After the reaction is complete, add 20 mL of 1N HCl solution and stir at room temperature for 1 hour. Add saturated potassium carbonate solution to adjust pH to 7-8, extract with chloroform, extract the aqueous phase with 100 mL of dichloromethane three times, combine the organic phases, dry with anhydrous magnesium sulfate, and purify the crude product by silica gel column chromatography to obtain the compound represented by Molecular Formula 8 (9.49 g, yield 79%). ¹³ C NMR (100 MHz, Chloroform-d) δ 148.40, 116.81, 113.20, 112.75, 104.79. HRMS: [C ₁₀ HN ₄ S ₂ ] ⁺ calculated: 240.9643, found: 240.9642.

Example 2

The synthetic route of molecular formula 100 is as follows:

The synthesis method of the compound specifically comprises the following steps:

Synthesis of intermediate M100: A chloroform solution (50 mL) containing liquid bromine (30 mL, 583 mmol) was added dropwise to a chloroform solution of selenopheno[3,2-b]selenophene (23.40 g, 100 mmol) at 0°C. 50mL), the dropwise addition was completed within 4h. After the dropwise addition was completed, the reaction was heated to room temperature, and then stirred under reflux for 3 h. Afterwards, a saturated NaOH aqueous solution was added to the reactant, and the above mixture was stirred under reflux for 1 h to remove excess bromine. Extract with chloroform, extract the aqueous phase three times with 100 mL of dichloromethane, combine the organic phases, dry over anhydrous magnesium sulfate, condense the organic solution under reduced pressure, and remove from the 1:1 (v/v) solution of chloroform and ethanol. The crude solid was recrystallized to obtain product M8 (51.66g, yield 94%) ¹³ C NMR (100MHz, Chloroform-d) δ 157.57, 133.44, 124.44.HRMS: [C ₆ HBr ₄ Se ₂ ] ⁺ calculated: 548.5142, found: 548.5140.

Synthesis of molecular formula 100: Weigh M100 (27.48g, 50mmol), cuprous cyanide (9.85g, 110mmol) and DMF (100mL) in a 500mL round-bottomed flask, stir and react at 140°C for 24 hours. After the reaction is completed, add 20 mL of 1N HCl solution and stir at room temperature for 1 hour. Add saturated potassium carbonate solution to adjust pH = 7-8, extract with chloroform, extract the aqueous phase three times with 100 mL of methylene chloride, combine the organic phases, and dry over anhydrous magnesium sulfate. The crude product is purified by silica gel column chromatography to obtain the molecular formula 100 The indicated compound (12.53 g, yield 75%). ¹³ C NMR (100 MHz, Chloroform-d) δ 158.68, 128.41, 122.42, 113.47, 113.42. HRMS: [C ₁₀ HN ₄ Se ₂ ] ⁺ calculated: 336.8532, found: 336.8531.

Example 3

The synthetic route of molecular formula 24 is as follows:

The synthesis method of the compound specifically includes the following steps:

Synthesis of Molecular Formula 24: Weigh Molecular Formula 8 (4.81 g, 20 mmol) in a 150 mL single-mouth bottle, add 35% hydrogen peroxide solution (10 mL), water (20 mL) and acetone (20 mL) and react in an ice-water bath for 6 hours. Add saturated brine (50 mL), extract with chloroform, extract the aqueous phase three times with 100 mL of dichloromethane, combine the organic phases, dry with anhydrous magnesium sulfate, and purify the crude product by silica gel column chromatography to obtain the compound represented by Molecular Formula 24 (4.66 g, yield 91%). ¹³ C NMR (100 MHz, Chloroform-d) δ 144.41, 143.38, 122.14, 119.99, 119.55, 118.52, 112.96, 112.86, 112.38, 110.74. HRMS: [C ₁₀ HN ₄ OS ₂ ] ⁺ calculated: 256.9592, found: 256.9591.

Example 4

The synthetic route of molecular formula 35 is as follows:

The synthesis method of the compound specifically includes the following steps:

Synthesis of molecular formula 35: Weigh molecular formula 8 (4.81g, 20mmol) into a 150mL single-mouth bottle, weigh potassium permanganate (6.96g, 44mmol) and dissolve it in 50mL water, and then slowly add it dropwise to the reaction bottle. After the dropwise addition was completed, the reaction was stirred at room temperature for 24 hours. Add saturated brine (50 mL) and extract with chloroform. The aqueous phase was extracted three times with 100 mL of methylene chloride. The organic phases were combined and dried over anhydrous magnesium sulfate. The crude product was purified by silica gel column chromatography to obtain the compound represented by molecular formula 35 ( 4.75g, yield 78%). ¹³ C NMR (100 MHz, Chloroform-d) δ 140.11, 128.74, 113.10, 109.59, 105.25. HRMS: [C ₁₀ HN ₄ O ₄ S ₂ ] ⁺ calculated: 304.9439, found: 304.9436.

Example 5

The synthetic route of molecular formula 45 is as follows:

The synthesis method of the compound specifically includes the following steps:

Synthesis of intermediate M45: Place thieno[3,4-b]thiophene (14.02g, 100mmol) and NBS (19.58g, 110mmol) in a 500mL round-bottomed flask and stir overnight in an ice-water bath. After the reaction is completed, add 1N sodium thiosulfate aqueous solution to wash, extract with chloroform, wash with water 3 times, and then dry with anhydrous magnesium sulfate. The crude product is purified by silica gel column chromatography to obtain product M45 (20.82g, product rate 95%). ¹ H NMR(400MHz,Chloroform-d)δ7.93(d,1H),7.69(d,1H),7.55(t,1H). ¹³ C NMR(100MHz,Chloroform-d)δ141.52,136.48,125.14,123.05 ,119.67,109.59.HRMS:[C ₆ H ₄ BrS ₂ ] ⁺ calculated:218.8938,found:218.8935.

Synthesis of molecular formula 45: Weigh M45 (10.96g, 50mmol), cuprous cyanide (5.37g, 60mmol) and DMF (100mL) in a 500mL round-bottomed flask, stir and react at 140°C for 24 hours. After the reaction is completed, add 20 mL of 1N HCl solution and stir at room temperature for 1 hour. Add saturated potassium carbonate solution to adjust pH = 7-8, extract with chloroform, extract the aqueous phase three times with 100 mL of methylene chloride, combine the organic phases, and dry over anhydrous magnesium sulfate. The crude product is purified by silica gel column chromatography to obtain molecular formula 45 The indicated compound (7.27g, yield 88%). ¹ H NMR(400MHz,Chloroform-d)δ8.03(d,1H),8.01(d,1H),7.66(t,1H). ¹³ C NMR(100MHz,Chloroform-d)δ142.84,136.52,128.92,123.64 ,120.53,114.74,108.49.HRMS:[C ₇ H ₄ NS ₂ ] ⁺ calculated:165.9785,found:165.9786.

Example 6

The synthetic route of molecular formula 63 is as follows:

The synthesis method of the compound specifically comprises the following steps:

Synthesis of intermediate M63: Take 3,6-difluorothio[3,2-b]thiophene (17.62g, 100mmol) and NBS (39.2g, 220mmol) in a 500mL round-bottomed flask, stir under an ice-water bath overnight. After the reaction is completed, add 2N sodium thiosulfate aqueous solution to wash, extract with chloroform, wash with water 3 times, and then dry with anhydrous magnesium sulfate. The crude product is purified by silica gel column chromatography to obtain product M63 (31.06g, product rate 93%). ¹³ C NMR (100MHz, Chloroform-d) δ 140.52, 127.82, 92.59.HRMS: [C ₆ HBr ₂ F ₂ S ₂ ] ⁺ calculated: 332.7854, found: 332.7853.

Synthesis of molecular formula 63: Weigh M63 (16.70g, 50mmol), cuprous cyanide (9.85g, 110mmol) and DMF (100mL) in a 500mL round-bottomed flask, stir and react at 140°C for 24 hours. After the reaction is completed, add 20 mL of 1N HCl solution and stir at room temperature for 1 hour. Add saturated potassium carbonate solution to adjust pH = 7-8, extract with chloroform, extract the aqueous phase three times with 100 mL of methylene chloride, combine the organic phases, and dry over anhydrous magnesium sulfate. The crude product is purified by silica gel column chromatography to obtain molecular formula 63. The indicated compound (9.50 g, yield 84%). ¹³ C NMR (100MHz, Chloroform-d) δ 151.86, 134.50, 107.75, 93.55.HRMS: [C ₈ HF ₂ N ₂ S ₂ ] ⁺ calculated: 226.9549, found: 226.9547.

Example 7

The synthetic route of molecular formula 189 is as follows:

The synthesis method of the compound specifically includes the following steps:

Synthesis of intermediate M189: Furano[3,2-b]furan (10.81 g, 100 mmol) and NBS (39.2 g, 220 mmol) were placed in a 500 mL round-bottom flask and stirred overnight in an ice-water bath. After the reaction, 2N sodium thiosulfate aqueous solution was added for washing, extracted with chloroform, washed with water three times, and dried over anhydrous magnesium sulfate. The crude product was purified by silica gel column chromatography to obtain product M189 (23.93 g, yield 90%). ¹ H NMR (400 MHz, Chloroform-d) δ6.94 (s, 2H). ¹³ C NMR (100 MHz, Chloroform-d) δ147.52, 123.36, 97.44. HRMS: [C ₆ H ₃ Br ₂ O ₂ ] ⁺ calculated: 264.8500, found: 264.8503.

Synthesis of molecular formula 189: Weigh M189 (13.29g, 50mmol), cuprous cyanide (9.85g, 110mmol) and DMF (100mL) in a 500mL round-bottomed flask, stir and react at 140°C for 24 hours. After the reaction is completed, add 20 mL of 1N HCl solution and stir at room temperature for 1 hour. Add saturated potassium carbonate solution to adjust pH = 7-8, extract with chloroform, extract the aqueous phase three times with 100 mL of methylene chloride, combine the organic phases, and dry over anhydrous magnesium sulfate. The crude product is purified by silica gel column chromatography to obtain molecular formula 189 The indicated compound (6.32g, yield 80%). ¹ H NMR (400MHz, Chloroform-d) δ7.06 (s, 2H). ¹³ C NMR (100MHz, Chloroform-d) δ 149.24, 129.09, 111.38, 106.98. HRMS: [C ₈ H ₃ N ₂ O ₂ ] ⁺ calculated:159.0195,found:159.0196.

Example 8

The synthetic route of molecular formula 209 is as follows:

The synthesis method of the compound specifically includes the following steps:

Synthesis of intermediate M209: Place thieno[3,2-b]furan (12.42g, 100mmol) and NBS (39.2g, 220mmol) in a 500mL round-bottomed flask and stir overnight in an ice-water bath. After the reaction is completed, add 2N sodium thiosulfate aqueous solution to wash, extract with chloroform, wash with water 3 times, and then dry with anhydrous magnesium sulfate. The crude product is purified by silica gel column chromatography to obtain product M209 (25.09g, product rate 89%). ¹ H NMR (400MHz, Chloroform-d) δ7.34 (s, 1H), 7.24 (s, 1H). ¹³ C NMR (100MHz, Chloroform-d) δ 156.30, 128.68, 123.98, 112.22, 111.66, 108.70. HRMS: [C ₆ H ₃ Br ₂ OS] ⁺ calculated:280.8271,found:280.8270.

Synthesis of molecular formula 209: Weigh M209 (14.10g, 50mmol), cuprous cyanide (9.85g, 110mmol) and DMF (100mL) in a 500mL round-bottomed flask, stir and react at 140°C for 24 hours. After the reaction is completed, add 20 mL of 1N HCl solution and stir at room temperature for 1 hour. Add saturated potassium carbonate solution to adjust pH = 7-8, extract with chloroform, extract the aqueous phase three times with 100 mL of methylene chloride, combine the organic phases, and dry over anhydrous magnesium sulfate. The crude product is purified by silica gel column chromatography to obtain molecular formula 209 The indicated compound (7.14g, yield 82%). ¹ H NMR (400MHz, Chloroform-d) δ7.57 (s, 1H), 7.46 (s, 1H). ¹³ C NMR (100MHz, Chloroform-d) δ 158.40, 131.78, 129.01, 120.01, 116.79, 114.57, 112.70, 111.44.HRMS:[C ₈ H ₃ N ₂ OS] ⁺ calculated:174.9966,found:174.9999.

Example 9

The synthetic route of molecular formula 246 is as follows:

The synthesis method of the compound specifically includes the following steps:

Synthesis of intermediate M246: A chloroform solution (50 mL) containing liquid bromine (13 mL, 250 mmol) was added dropwise to 2,3-difluoroselenopheno[3,2-b]thiophene (22.31 g, 100 mmol) at 0°C. ) in chloroform solution (50 mL), and the dropwise addition was completed within 4 hours. After the dropwise addition was completed, the reaction was heated to room temperature, and then stirred under reflux for 3 h. Then, a saturated aqueous NaOH solution was added to the reactant, and the above mixture was stirred under reflux for 1 hour to remove excess bromine. Extract with chloroform, extract the aqueous phase three times with 100 mL of dichloromethane, combine the organic phases, dry over anhydrous magnesium sulfate, condense the organic solution under reduced pressure, and remove from the 1:1 (v/v) solution of chloroform and ethanol. The crude solid was recrystallized to give product M246 (35.04 g, 92% yield). ¹³ C NMR (100MHz, Chloroform-d) δ 146.81, 143.17, 141.03, 122.15, 114.13, 111.27. HRMS: [C ₆ HF ₂ Br ₂ SSe] ⁺ calculated: 380.7299, found: 380.7296.

Synthesis of molecular formula 246: Weigh M246 (7.62g, 20mmol), cuprous cyanide (9.85g, 110mmol) and DMF (100mL) in a 500mL round-bottomed flask, stir and react at 140°C for 24 hours. After the reaction is completed, add 20 mL of 1N HCl solution and stir at room temperature for 1 hour. Add saturated potassium carbonate solution to adjust pH = 7-8, extract with chloroform, extract the aqueous phase three times with 100 mL of methylene chloride, combine the organic phases, and dry over anhydrous magnesium sulfate. The crude product is purified by silica gel column chromatography to obtain molecular formula 246 The indicated compound (4.75 g, yield 87%). ¹³ C NMR (100MHz, Chloroform-d) δ 148.93, 147.76, 145.85, 123.88, 116.23, 112.57, 112.22, 108.41. HRMS: [C ₈ HF ₂ N ₂ SSe] ⁺ calculated: 274.8994, found: 274.8991.

Example 10

The synthetic route of molecular formula 267 is as follows:

The synthesis method of the compound specifically comprises the following steps:

Synthesis of intermediate M267: Take deuterated 3,6-difluoroselenopheno[3,2-b]furan (17.31g, 100mmol) and NBS (39.2g, 220mmol) in a 500mL round-bottomed flask, and place on ice Stir overnight in a water bath. After the reaction is completed, add 2N sodium thiosulfate aqueous solution to wash, extract with chloroform, wash with water 3 times, and then dry with anhydrous magnesium sulfate. The crude product is purified by silica gel column chromatography to obtain product M267 (28.12g, product rate 85%). ¹³ C NMR (100MHz, Chloroform-d) δ 155.82, 128.30, 125.26, 125.25, 118.36, 110.16. HRMS: [C ₆ HD ₂ Br ₂ OSe] ⁺ calculated: 330.7841, found: 330.7839.

Synthesis of molecular formula 267: Weigh M267 (16.54g, 50mmol), cuprous cyanide (9.85g, 110mmol) and DMF (100mL) in a 500mL round-bottomed flask, stir and react at 140°C for 24 hours. After the reaction is completed, add 20 mL of 1N HCl solution and stir at room temperature for 1 hour. Add saturated potassium carbonate solution to adjust pH = 7-8, extract with chloroform, extract the aqueous phase three times with 100 mL of methylene chloride, combine the organic phases, and dry over anhydrous magnesium sulfate. The crude product is purified by silica gel column chromatography to obtain molecular formula 267 The indicated compound (9.15g, yield 82%). ¹³ C NMR (100MHz, Chloroform-d) δ 157.64, 134.15, 131.77, 125.56, 119.16, 116.96, 115.29, 111.39. HRMS: [C ₈ HD ₂ N ₂ OSe] ⁺ calculated: 224.9536, found: 224.9531.

Example 11

The synthetic route of molecular formula 270 is as follows:

The synthesis method of the compound specifically includes the following steps:

Synthesis of intermediate M270: Put thieno[3,2-b]thiophene (14.02g, 100mmol) and NBS (39.2g, 220mmol) in a 500mL round-bottomed flask, and stir in an ice-water bath overnight. After the reaction is completed, add 2N sodium thiosulfate aqueous solution to wash, extract with chloroform, wash with water three times, and then dry with anhydrous magnesium sulfate. The crude product is purified by silica gel column chromatography and collected. Weigh the product from the previous step (14.90g, 50mmol), cuprous cyanide (9.85g, 110mmol) and DMF (100mL) into a 500mL round-bottomed flask, stir and react at 140°C for 24 hours. After the reaction is completed, add 20 mL of 1N HCl solution and stir at room temperature for 1 hour. Add saturated potassium carbonate solution to adjust pH = 7-8, extract with chloroform, extract the aqueous phase three times with 100 mL of methylene chloride, combine the organic phases, and dry over anhydrous magnesium sulfate. The crude product is purified by silica gel column chromatography to obtain the intermediate. Compound represented by M270 (8.08g, yield 85%). ¹ H NMR (400MHz, Chloroform-d) δ 7.86 (s, 2H). ¹³ C NMR (100MHz, Chloroform-d) δ 143.39, 132.20, 114.45, 113.22. HRMS: [C ₈ H ₃ N ₂ S ₂ ] ⁺ calculated:190.9738,found:190.9735.

Synthesis of molecular formula 270: Under nitrogen atmosphere and anhydrous conditions, n-BuLi (27 mL, 67.5 mmol) was slowly added to a solution of M270 (9.49 g, 49.9 mmol) in 50 mL THF at 0°C, and the mixture was stirred for 1 hour. . Next, tri-n-butyltin chloride (19 mL, 70 mmol) was added to the reaction mixture, and the mixture was stirred at 0°C for 30 minutes, then warmed to room temperature and stirred for 12 hours. After simple filtration under nitrogen, THF was removed under vacuum and 50 mL of toluene was charged. The toluene solution was then transferred to a solution of pentafluorobromobenzene (6 mL, 50 mmol) and tetrakis(triphenylphosphine)palladium (2.3 g, 1.9 mmol) in toluene (40 mL) and the mixture was refluxed at 140°C for 2 days. After cooling to room temperature, the mixture was filtered through a celite column with toluene. Finally, the toluene solutions were combined and concentrated, and recrystallized from chloroform to obtain the compound represented by molecular formula 270 (16.00 g, yield 90%). ¹ H NMR (400MHz, Chloroform-d) δ7.86 (s, 1H). ¹³ C NMR (100MHz, Chloroform-d) δ 150.51 (ddt), 150.39 (t), 149.49 (ddt), 141.72, 137.60 ( dtt),135.72(dtt),131.93,128.08(tt),116.35,114.67,113.97,112.00(t),111.45(m).HRMS:[C ₁₄ H ₂ F ₅ N ₂ S ₂ ] ⁺ calculated:356.9580, found:356.9583.

Example 12

The present invention provides an organic light-emitting device based on a hole injection material composed of thiophene derivatives, furan derivatives and selenium phenol derivatives substituted by electron-deficient groups such as cyano, fluorine, pentafluorophenyl, etc., as shown in Figure 1 As shown, the metal cathode 191, the electron injection layer 180, the electron transport layer 160, the light emitting layer 150, the hole transport layer 140, the hole injection layer 130, the anode 120 and the glass substrate 110 are stacked in sequence from top to bottom. Device preparation The process is evaporation method.

The metal cathode is aluminum, with a deposition rate of 0.1-0.3nm/s and a thickness of 100nm;

The electron injection layer uses the material synthesized by this patent and the commercial hole injection material LMZ-2178, with an evaporation rate of 0.05-0.1nm/s and a thickness of 1nm;

The electron transport layer uses the compound LET003 with the following structure, the evaporation rate is 0.05-0.1nm/s, and the thickness is 40nm;

The light-emitting layer is formed by co-doping host material and guest material. The host material is the currently commercialized host material LBH001, and the guest material is LBD001 with the following structure. The doping mass ratio of the host material to the guest material is 90:10. The plating rate is 0.003-0.2nm/s, and the thickness is 40nm;

The electron blocking layer uses the compound LEB001 with the following structure, the evaporation rate is 0.05-0.1nm/s, and the thickness is 10nm;

The hole transport layer uses a compound NPB having the following structure, with a deposition rate of 0.05-0.1 nm/s and a thickness of 100 nm;

The anode 7 is made of indium tin oxide (ITO).

Table 1. Device performance table

As can be seen from Table 1, compared with commercial materials, the hole injection layer materials provided by the present invention have lower turn-on voltage, higher current efficiency and longer lifespan of the device.

Example 13

The present invention compares the HOMO and LUMO orbital energies of different materials with commercial LMZ-2178. Compare the hole injection layer material in the present invention with currently commercialized materials.

Table 2. Performance values of the material of the present invention and commercial LMZ-2178

It can be seen from the measured data that compared with commercial materials, the hole injection layer material provided by the present invention has deeper HOMO and LUMO energy levels and a slightly higher energy band width, which is more conducive to hole injection from the anode into the organic layer. This shows that it can be better used in organic light-emitting devices to achieve better display effects.

To sum up, when the hole injection layer material provided by the present invention is applied to an organic light-emitting device, it can effectively improve the performance of the device, including efficiency and working life.

Example 14

The structure of the perovskite solar cell provided in this embodiment is shown in FIG2 , and the specific preparation process is as follows:

The ITO conductive glass was washed ultrasonically with acetone, deionized water, and isopropyl alcohol in sequence, and dried under vacuum at 80°C for 12 hours. A hole injection layer film is evaporated on ITO, and then PTAA is spin-coated as a hole transport layer. Prepare the perovskite precursor solution, dissolve it in DMSO, spin-coat it on the PTAA film, and anneal it at 100°C for 10 minutes. Configure the electron transport layer solution, dissolve PCBM in chlorobenzene at a concentration of 10 mg/ml, and prepare it on the perovskite film by spin coating. Then, the methanol solution of BCP was spin-coated on the PCBM, and finally the metallic silver electrode was vacuum evaporated.

The performance of the finally prepared perovskite solar cell device is shown in Table 3 below:

Hole injection layer configuration	Voc(V)	Jsc(mA/cm 2 )	FF(%)	PCE(%)
none	1.12	21.68	68.17	16.55
Molecular formula 8	1.21	22.28	73.51	17.95
Molecular formula 24	1.18	22.37	77.78	20.15
Molecular formula 35	1.13	23.01	75.98	19.88
Molecular formula 45	1.10	22.58	79.54	21.35
Molecular formula 63	1.12	21.16	80.53	20.03
Molecular formula 100	1.17	22.33	74.05	20.55
Molecular formula 189	1.11	22.92	73.18	20.06
Molecular formula 209	1.15	22.86	79.21	19.68
Molecular formula 246	1.16	22.35	79.28	19.65
Molecular formula 267	1.15	22.89	79.35	19.87
Molecular formula 270	1.16	22.38	79.48	20.56

The structures of organic hole injection materials listed above are only partial representatives. Other compounds containing five-membered rings with the same idea and strong electron-pulling groups on the periphery are within the scope of this patent protection.

Although the embodiments of the present invention have been shown and described above, it can be understood that the above-mentioned embodiments are illustrative and should not be construed as limitations of the present invention. Those of ordinary skill in the art can make modifications to the above-mentioned embodiments within the scope of the present invention. The embodiments are subject to changes, modifications, substitutions and variations.

Claims (8)

1. An organic hole injection material is characterized in that its general structural formula is as follows:

   

   Among them, X, Y and Z are each independently selected from C, O, CO, S, Se, SO, SeO, SO ₂ or SeO ₂ ;

   At least one of R ₁ , R ₂ , R ₃ and R ₄ is selected from F, CN,

   

   or

   

   The remainder is hydrogen.
2. The organic hole injection material according to claim 1, characterized in that Y or Z are different, and one of Y or Z is C.
3. The organic hole injection material according to claim 2, characterized in that:

   When Y=C, its general structural formula is:

   

   When Z=C, its general structural formula is:

   
4. The organic hole injection material according to any one of claims 1 to 3, characterized in that at least two of R ₁ , R ₂ , R ₃ and R ₄ are selected from F, CN,

   

   or

   

   The same or different from each other.
5. The organic hole injection material according to claim 1, characterized in that part or all of the hydrogen in the molecular formula is replaced by deuterium.
6. The organic hole injection material according to claim 1, characterized in that it is represented by any one of the following compounds:

   

   

   

   

   

   

   

   

   

   

   
7. An organic light-emitting device, characterized in that it comprises a cathode, an anode and various organic layers; wherein the electron injection layer uses the organic hole injection material described in any one of claims 1 to 6.
8. A perovskite solar cell, characterized in that it includes a cathode, an anode and each organic layer; wherein, the hole injection layer uses the organic hole injection material according to any one of claims 1-6.

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