Polybenzocarbazole derivative as well as preparation method and application thereof

Abstract

The invention discloses a polybenzocarbazole derivative as well as a preparation method and application thereof, the polybenzocarbazole derivative has a structure as shown in a formula (I), and Ar is an aromatic group; the linker is selected from one of straight-chain alkyl, phenyl or biphenyl with the carbon atom number of 2-8; n is the number of repetitive units and ranges from 5 to 1000. A repeating unit adopted by the polybenzocarbazole derivative is a conjugated unit composed of the benzocarbazole derivative, phenyl and thienyl, and compared with a small-molecule self-assembly material, the polybenzocarbazole derivative shows good hole transport capacity, and the hole transport efficiency is improved. And due to the excellent characteristics in the aspects of conductivity and wettability on a conductive substrate, the material has inclusivity to the layer thickness, has good photo-thermal stability, and lays a good foundation for commercial application of solar cell modules. # imgabs0 #

Description

Technical Field

[0001] The invention relates to the field of optoelectronic functional devices, and in particular to a polybenzocarbazole derivative and a preparation method and application thereof. Background Art

[0002] On September 22, 2020, at the general debate of the 75th United Nations General Assembly, the Chinese government proposed to adopt strong policies and measures to strive to peak carbon dioxide emissions by 2030 and achieve carbon neutrality by 2060. The power generation industry is an important source of carbon dioxide emissions, and its carbon dioxide emissions account for more than 1 / 3 of the total carbon dioxide emissions from fossil fuel combustion in the world. In my country, carbon dioxide emissions from the power sector account for more than 40% of the country's total carbon dioxide emissions. In order to effectively promote and achieve the dual carbon goals, the power industry is the key to carbon emission reduction, and the development of clean energy technologies such as photovoltaic power generation and wind power generation has become inevitable.

[0003] As an important clean and renewable energy source, solar power generation is an important part of coping with the transformation of the global energy structure and achieving the dual carbon goals. Hole transport materials play a vital role in solar cells, especially in organic solar cells and perovskite solar cells. In the cell device, it effectively transports photogenerated holes, ensures the rapid migration and separation of charges, and finally reaches the electrode to generate current.

[0004] At present, self-assembled monolayer (SAM) materials are the most outstanding among hole transport materials. They have the advantages of easy adjustment of substrate work function, small optical and electrical losses, and good compatibility with stacked cells. The development of SAM molecules has strongly promoted the efficiency of inverted perovskite solar cells to exceed 26%.

[0005] Patent document CN118251024A discloses a solar cell, including a glass substrate and a transparent conductive layer, a first hole transport layer and a perovskite layer stacked in sequence on the surface of one side of the glass substrate, wherein the first hole transport layer includes at least one SAM layer, and the method for preparing the SAM layer includes: coating a solution containing a SAM raw material on the side of the transparent conductive layer away from the glass substrate, and performing a first annealing treatment to obtain a SAM prefabricated layer; washing the SAM prefabricated layer with a first solvent, and then performing a second annealing treatment on the washed SAM prefabricated layer to form a SAM layer, wherein the first solvent is the same as the solvent used in the precursor solution for preparing the perovskite layer. The invention can improve the interface contact ability between the perovskite layer and the SAM layer, which is conducive to better carrier transmission and better crystal growth.

[0006] Although the use of SAM as a hole transport material in the existing technology can improve device efficiency and stability to some extent, most SAM molecules are difficult to form a dense and uniform single-molecule hole transport layer during solution processing, and SAM molecules are difficult to achieve complete coverage on a rough conductive glass substrate, and diffuse into the perovskite active layer in the battery device due to environmental factors. These problems need to be solved urgently.

[0007] In order to continue to advance the technology of organic solar cells and perovskite solar cells and further improve device efficiency and stability, it is crucial to develop new high-efficiency hole transport materials. Summary of the invention

[0008] The purpose of the present invention is to provide a polybenzocarbazole derivative and a preparation method and application thereof, so as to solve the problems existing in the prior art that it is difficult for SAM molecules to form a dense and uniform single-molecule hole transport layer during processing and it is difficult to achieve complete coverage on a rough conductive glass substrate, thereby improving the efficiency and stability of solar cell devices.

[0009] The first aspect of the present invention provides a polybenzocarbazole derivative, the structure of which is shown in formula (I):

[0010]

[0011] Wherein, Ar is an aromatic group; linker is selected from a linear alkyl group having 2 to 8 carbon atoms, a phenyl group or a biphenyl group; and n is the number of repeating units, which is between 5 and 1000.

[0012] The repeating unit used in the polybenzocarbazole derivative of the present invention is a conjugated unit composed of a benzocarbazole derivative, a phenyl group and a thiophene group. Compared with the small molecule benzocarbazole phosphate SAM, the polybenzocarbazole derivative has a larger π conjugated structure, which is conducive to the production of better π-π stacking of molecules, and the larger conjugated system is also more conducive to the transmission of charge between molecules, thereby improving the efficiency of battery devices. A straight chain alkyl or a rigid benzene ring is introduced into the linker for modification (partially or completely replacing the flexible alkyl chain part), which optimizes the absorption band of the hole transport material to ultraviolet light, thereby improving the resistance of the battery device to ultraviolet light, and due to the enhanced π-π stacking between molecules and inside molecules, a more compact and orderly hole transport layer is formed on the substrate. In addition, the polymer structure connected by multiple conjugated repeating units can effectively alleviate the problem that the small molecule SAM is easy to diffuse to the photoactive layer (such as the perovskite active layer) and improve the uneven coverage of the small molecule SAM on the conductive glass substrate, and finally achieve the improvement of the efficiency and stability of the battery device.

[0013] Preferably, Ar is selected from one of the following structures:

[0014]

[0015] Among them, R1, R2, and R3 are independently selected from hydrogen atoms, fluorine atoms, chlorine atoms, bromine atoms, aldehyde groups, amino groups, polyether chains, straight-chain or branched alkyl groups with 1 to 50 carbon atoms, alkoxy groups, substituted or unsubstituted halogenated alkyl groups with 1 to 50 carbon atoms, substituted or unsubstituted aryl groups with 1 to 50 carbon atoms, and substituted or unsubstituted heteroaryl groups with 1 to 50 carbon atoms.

[0016] Preferably, the linker is selected from one of the following structures:

[0017]

[0018] Wherein, n is the number of repeating units, and its value is between 1 and 4.

[0019] The second aspect of the present invention provides a method for preparing the polybenzocarbazole derivative, comprising the following steps:

[0020] (1) dissolving a halogen-substituted benzocarbazole derivative monomer having a phosphate group in an organic solvent, adding a tin- or borate-substituted aromatic group monomer, performing a polymerization reaction under the action of a metal catalyst, and obtaining a polybenzocarbazole derivative intermediate through sedimentation and Soxhlet extraction;

[0021] (2) dissolving the polybenzocarbazole derivative intermediate in an organic solvent 2, adding trimethylsilyl bromide to carry out a reaction, and after the reaction is completed, quenching with alcohols and treating the reaction product with a poor solvent to obtain the polybenzocarbazole derivative.

[0022] Preferably, in step (1), the structure of the halogen-substituted benzocarbazole derivative monomer having a phosphate group is as shown in formula (II):

[0023]

[0024] Wherein X represents a halogen atom, and linker is a straight-chain alkyl group having 2 to 8 carbon atoms, a phenyl group or a biphenyl group.

[0025] Preferably, in step (1), the organic solvent 1 comprises N,N-dimethylformamide, dimethyl sulfoxide, tetrahydrofuran or toluene, preferably N,N-dimethylformamide (DMF).

[0026] Preferably, the structure of the tin-based or borate-substituted aromatic group monomer is as shown in formula (III) or formula (IV):

[0027]

[0028] Wherein, Ar is an aromatic group; R is independently selected from an alkyl group or an aryl group, and n is the number of R groups, which is 3.

[0029] Preferably, in step (1), the molar ratio of the halogen-substituted benzocarbazole derivative monomer with a phosphate group to the tin- or borate-substituted aromatic group monomer is 1:0.2-5.

[0030] Preferably, the metal catalyst comprises tetrakistriphenylphosphine palladium, palladium chloride, palladium acetate or [1,1′-bis(di-tert-butylphosphino)ferrocene]dichloropalladium(II).

[0031] Preferably, the amount of the metal catalyst used is 3-10% of the molar amount of the halogen-substituted benzocarbazole derivative monomer with a phosphate group.

[0032] Preferably, in step (1), the polymerization reaction conditions are: heating under reflux for 12 to 36 hours.

[0033] Preferably, in step (2), the organic solvent comprises dichloromethane, 1,4-dioxane or chloroform, preferably dichloromethane.

[0034] Preferably, in step (2), the molar ratio of the polybenzocarbazole derivative intermediate to trimethylsilyl bromide is 1:10-20.

[0035] Preferably, in step (2), the reaction time is 12 to 36 hours.

[0036] The synthetic route of the polybenzocarbazole derivative is:

[0037]

[0038] Preferably, the halogen-substituted benzocarbazole derivative monomer with a phosphate group is prepared by the following method:

[0039] Step 1: Under an inert atmosphere, dissolve the benzocarbazole with a halogen group in an organic solvent 3, add a linker with a bromine end group, heat under reflux in an alkaline environment, and react under the action of a catalyst to obtain an intermediate product;

[0040] Step 2: Mix the intermediate product obtained in step 1 with triethyl phosphite, heat and reflux to carry out Arbuzal reaction, and obtain the halogen-substituted benzocarbazole derivative monomer with a phosphate group.

[0041] Preferably, in step one, the organic solvent three comprises acetone, toluene or tetrahydrofuran, preferably acetone.

[0042] Preferably, in step 1, the ratio of the benzocarbazole with a halogen group to the linker with a bromine end group is 1:5-20.

[0043] Preferably, in step 1, the catalyst comprises tetrabutylammonium bromide (TBAB) or sodium hydride.

[0044] Preferably, in step 1, the amount of the catalyst used is 10-30% of the molar amount of the benzocarbazole with a halogen group.

[0045] Preferably, in step 2, the molar ratio of the intermediate product to triethyl phosphite is 1:10-30.

[0046] Preferably, in step 2, the heating reflux temperature is 130°C to 170°C.

[0047] The preparation route of the halogen-substituted benzocarbazole derivative monomer with a phosphate group is as follows:

[0048]

[0049] Wherein X represents a halogen atom, and linker is a straight-chain alkyl group having 2 to 8 carbon atoms, a phenyl group or a biphenyl group.

[0050] The third aspect of the present invention provides the use of the polybenzocarbazole derivative in a photoelectric functional device. The photoelectric functional device of the present invention includes an organic solar cell and a perovskite solar cell. The polybenzocarbazole derivative of the present invention exhibits good hole transport capability, excellent properties in terms of conductivity and wettability on a conductive substrate, making it tolerant to layer thickness, and having good photothermal stability. Its development lays a good foundation for the commercial application of solar cell modules.

[0051] The fourth aspect of the present invention provides an organic solar cell, comprising a cathode layer, a cathode buffer layer, a photoactive layer, an anode buffer layer and an anode layer stacked in sequence, wherein the anode buffer layer contains the polybenzocarbazole derivative.

[0052] The fifth aspect of the present invention provides a perovskite solar cell, comprising a cathode layer, a hole blocking layer, an electron transport layer, a perovskite active layer, an anode modification layer and an anode layer stacked in sequence, wherein the anode modification layer contains the polybenzocarbazole derivative.

[0053] Compared with the prior art, the present invention has at least the following beneficial effects:

[0054] (1) The repeating unit used in the polybenzocarbazole derivative of the present invention is a conjugated unit composed of a benzocarbazole derivative, a phenyl group and a thiophene group. Compared with the small molecule benzocarbazole phosphate SAM, the polybenzocarbazole derivative has a larger π conjugated structure, which is conducive to better π-π stacking of the molecule, and the larger conjugated system is also more conducive to the transfer of charge between molecules, thereby improving the efficiency of the battery device. The introduction of a straight chain alkyl or a rigid benzene ring into the linker for modification (partially or completely replacing the flexible alkyl chain part) optimizes the absorption band of the hole transport material to ultraviolet light, thereby improving the resistance of the battery device to ultraviolet light, and due to the enhanced π-π stacking between molecules and within molecules, a more compact and orderly hole transport layer is formed on the substrate. In addition, the polymer structure connected by multiple conjugated repeating units can effectively alleviate the problem that the small molecule SAM is easy to diffuse into the photoactive layer (such as the perovskite active layer) and improve the uneven coverage of the small molecule SAM on the conductive glass substrate, ultimately achieving the improvement of the efficiency and stability of the battery device.

[0055] (2) The solar cell prepared by using the polybenzocarbazole derivative of the present invention exhibits good hole transport capability, and the excellent properties in terms of conductivity and wettability on the conductive substrate make it tolerant to layer thickness, and has good photothermal stability. Its development lays a good foundation for the commercial application of solar cell modules. BRIEF DESCRIPTION OF THE DRAWINGS

[0056] Figure 1 The schematic diagram of the structure of the perovskite solar cell device of the present invention; the device structures 1 to 6 are respectively a cathode layer (1), a hole blocking layer (2), an electron transport layer (3), a perovskite active layer (4), an anode modification layer (5) and an anode layer (6).

[0057] Figure 2 The schematic diagram of the structure of the organic solar cell device of the present invention; the device structures 1 to 5 are respectively a cathode layer (1), a cathode buffer layer (2), a photoactive layer (3), an anode buffer layer (4) and an anode layer (5). DETAILED DESCRIPTION

[0058] The preparation process of the benzocarbazole derivative monomer (the halogen-substituted benzocarbazole derivative monomer having a phosphate group) in the embodiment of the present invention is as follows:

[0059] Step 1: Under the protection of inert gas argon, 1 molar equivalent of benzocarbazole with a halogen group is dissolved in acetone, and then 15 times the molar equivalent of a linker with a bromine end group is added, and the mixture is heated to reflux in an alkaline environment, and the reaction is catalyzed by 20% molar amount of tetrabutylammonium bromide (TBAB).

[0060] Step 2: The product obtained in the first step (1 molar equivalent) is mixed with 10 molar equivalents of triethyl phosphite, and heated under reflux at 160° C. to perform Arbuzal reaction to obtain a benzocarbazole derivative monomer.

[0061] The preparation route is as follows:

[0062]

[0063] The four benzocarbazole derivative monomers in the examples of the present invention are all prepared by the above method.

[0064] Example 1: Synthesis of polybenzocarbazole derivative CS-1

[0065]

[0066] Preparation method of polybenzocarbazole derivative intermediate 1: Add benzocarbazole phosphate (0.22g, 0.40mmol), tetrakistriphenylphosphine palladium (10mg) and 20mL N,N-dimethylformamide (DMF) to a two-necked bottle, stir under nitrogen protection until the solution is clear, then add 2,5-bis(trimethyltinyl)thiophene (0.16g, 0.40mmol) at room temperature, and heat to reflux for 24h. After the reaction is completed, add 10ml hydrochloric acid solution for post-treatment and extract with chloroform. The organic phase is slowly dripped into ether to precipitate a yellow solid, which is filtered and dried to obtain a crude product. Extract with n-hexane and ether for 12h respectively, and finally obtain 0.12g of yellow solid CS-1M with a yield of 61%.

[0067]

[0068] Preparation method 2 of polybenzocarbazole derivative intermediate: In a two-necked bottle, add reaction substrate (benzocarbazole phosphate) (0.22g, 0.40mmol), 20mL DMF, tetrakistriphenylphosphine palladium (10mg), add thiophene-2,5-diboronic acid dipinacol ester (0.13g, 0.40mmol) at room temperature under nitrogen protection, and heat under reflux for 24h. After the reaction is completed, the post-treatment is the same as the preparation method 1 to obtain CS-1M (intermediate).

[0069] Take 40 mg of the polybenzocarbazole derivative CS-1M (intermediate) obtained by the above reaction and dissolve it in 15 ml of dichloromethane. Add 2 ml of trimethylsilyl bromide under nitrogen protection and stir at room temperature for 12 hours. After the reaction is completed, add 5 ml of methanol to the system to remove excess trimethylsilyl bromide and stir for 3 hours. Concentrate the solution by vacuum distillation, then add sufficient deionized water for precipitation. After the precipitated product is filtered and dried, 25 mg of green solid is obtained with a yield of 70%, which is the polybenzocarbazole derivative CS-1. TOF-MS (APCI): m / z [M+H] 1467.871. The structural formula is as follows:

[0070]

[0071] Example 2: Synthesis of polybenzocarbazole derivative CS-2

[0072]

[0073] In a two-necked flask, add benzocarbazole phosphate (0.22g, 0.40mmol), tetrakistriphenylphosphine palladium (10mg) and 20mL N,N-dimethylformamide (DMF), stir under nitrogen protection until the solution is clear, then add methoxy-tin-based thiophene (0.17g, 0.40mmol) at room temperature, and heat to reflux for 24h. After the reaction is completed, add 10ml hydrochloric acid solution for post-treatment and extract with chloroform. The organic phase is slowly dripped into ether to precipitate a brown solid, which is filtered and dried to obtain a crude product. Extract with n-hexane and ether for 12h respectively, and finally obtain 0.10g of brown solid CS-2M with a yield of 50%.

[0074] Take 30 mg of the polybenzocarbazole derivative CS-2M obtained by the above reaction and dissolve it in 15 ml of dichloromethane. Add 2 ml of trimethylsilyl bromide dropwise under nitrogen protection and stir at room temperature for 12 hours. After the reaction is completed, add 5 ml of methanol to the system to remove excess trimethylsilyl bromide and stir for 3 hours. Concentrate the solution by vacuum distillation, then add sufficient deionized water for precipitation. After the precipitated product is filtered and dried, 15 mg of yellow solid is obtained with a yield of 56%. The structural formula of the polybenzocarbazole derivative CS-2 is as follows:

[0075]

[0076] Example 3: Synthesis of polybenzocarbazole derivative CS-3

[0077]

[0078] In a two-necked flask, add benzocarbazole substrate (0.12g, 0.20mmol), tetrakistriphenylphosphine palladium (5mg) and 15mL N,N-dimethylformamide (DMF), stir under nitrogen protection until the solution is clear, then add methoxytinylthiophene (0.09g, 0.20mmol) at room temperature, and heat to reflux for 24h. After the reaction is completed, add 10ml hydrochloric acid solution for post-treatment and extract with chloroform. The organic phase is slowly dripped into ether to precipitate a brown solid, which is filtered and dried to obtain a crude product. Extract with n-hexane and ether for 12h respectively, and finally obtain 0.08g of light yellow solid CS-3M with a yield of 73%.

[0079] Take 30 mg of the polybenzocarbazole derivative CS-3M obtained by the above reaction and dissolve it in 15 ml of dichloromethane. Add 2 ml of trimethylsilyl bromide under nitrogen protection and stir at room temperature for 12 hours. After the reaction is completed, add 5 ml of methanol to the system to remove excess trimethylsilyl bromide and stir for 3 hours. Concentrate the solution by vacuum distillation, then add sufficient deionized water for precipitation. After the precipitated product is filtered and dried, 18 mg of yellow solid is obtained, with a yield of 66%, which is the polybenzocarbazole derivative CS-3. The structural formula is as follows:

[0080]

[0081] Example 4: Synthesis of polybenzocarbazole derivative CS-4

[0082]

[0083] In a two-necked flask, add benzocarbazole phosphate (0.11g, 0.20mmol), tetrakistriphenylphosphine palladium (5mg) and 15mL N,N-dimethylformamide (DMF), stir under nitrogen protection until the solution is clear, then add tin-based thiophene with epoxyalkyl group (0.14g, 0.20mmol) at room temperature, and heat to reflux for 24h. After the reaction is completed, add 10ml hydrochloric acid solution for post-treatment and extract with chloroform. The organic phase is slowly dripped into ether, and the precipitated solid is filtered and dried to obtain a crude product. Extract with n-hexane and ether for 12h respectively, and finally obtain 0.05g of brown-red solid CS-4M with a yield of 51%.

[0084] Take 20 mg of the polybenzocarbazole derivative intermediate CS-4M obtained by the above reaction and dissolve it in 15 ml of dichloromethane. Add 2 ml of trimethylsilyl bromide under nitrogen protection and stir at room temperature for 12 hours. After the reaction is completed, add 5 ml of methanol to the system to remove excess trimethylsilyl bromide and stir for 3 hours. Concentrate the solution by vacuum distillation, then add sufficient deionized water for precipitation. After the precipitated product is filtered and dried, 10 mg of dark brown solid is obtained with a yield of 55%, which is the polybenzocarbazole derivative CS-4. The structural formula is as follows:

[0085]

[0086] Example 5: Synthesis of polybenzocarbazole derivative CS-5

[0087]

[0088] In a two-necked flask, add benzocarbazole phosphate (0.11g, 0.20mmol), tetrakistriphenylphosphine palladium (5mg) and 15mL N,N-dimethylformamide (DMF), stir under nitrogen protection until the solution is clear, then add tin-based thiophene with a polyether chain (0.14g, 0.20mmol) at room temperature, and heat to reflux for 24h. After the reaction is completed, add 10ml of hydrochloric acid solution for post-treatment and extract with chloroform. The organic phase is slowly dripped into ether, and the precipitated solid is filtered and dried to obtain a crude product. Extract with n-hexane and ether for 12h respectively, and finally obtain 0.08g of red solid CS-5M with a yield of 47%.

[0089] Take 40 mg of the polybenzocarbazole derivative CS-5M obtained by the above reaction and dissolve it in 20 ml of dichloromethane. Add 3 ml of trimethylsilyl bromide under nitrogen protection and stir at room temperature for 12 hours. After the reaction is completed, add 5 ml of methanol to the system to remove excess trimethylsilyl bromide and stir for 3 hours. Concentrate the solution by vacuum distillation, then add sufficient deionized water for precipitation. After the precipitated product is filtered and dried, 27 mg of brown-red solid is obtained, with a yield of 72%, which is the polybenzocarbazole derivative CS-5. The structural formula is as follows:

[0090]

[0091] Example 6: Synthesis of polybenzocarbazole derivative CS-6

[0092]

[0093] In a two-necked flask, add benzocarbazole substrate (0.11g, 0.20mmol), tetrakistriphenylphosphine palladium (5mg) and 15mL N,N-dimethylformamide (DMF), stir under nitrogen protection until the solution is clear, then add tin-based thiophene with polyether chain (0.14g, 0.20mmol) at room temperature, and heat to reflux for 24h. After the reaction is completed, add 10ml hydrochloric acid solution for post-treatment and extract with chloroform. The organic phase is slowly dripped into ether, and the precipitated solid is filtered and dried to obtain a crude product. Extract with n-hexane and ether for 12h respectively, and finally obtain 0.08g of red solid CS-6 intermediate with a yield of 49%.

[0094] Take 40 mg of the polybenzocarbazole derivative CS-6 intermediate obtained by the above reaction and dissolve it in 20 ml of dichloromethane. Add 3 ml of trimethylsilyl bromide under nitrogen protection and stir at room temperature for 12 hours. After the reaction is completed, add 5 ml of methanol to the system to remove excess trimethylsilyl bromide and stir for 3 hours. Concentrate the solution by vacuum distillation, then add sufficient deionized water for precipitation. After the precipitated product is filtered and dried, 25 mg of dark red solid is obtained with a yield of 67%, which is the polybenzocarbazole derivative CS-6. The structural formula is as follows:

[0095]

[0096] Example 7: Synthesis of polybenzocarbazole derivative CS-7

[0097]

[0098] In a two-necked flask, add benzocarbazole phosphate (0.11g, 0.20mmol), tetrakistriphenylphosphine palladium (5mg) and 15mL N,N-dimethylformamide (DMF), stir under nitrogen protection until the solution is clear, then add 2,6-di(trimethyltinyl)benzo[1,2-b:4,5-b']dithiophene (0.10g, 0.20mmol) at room temperature, and heat to reflux for 24h. After the reaction is completed, add 10ml hydrochloric acid solution for post-treatment and extract with chloroform. The organic phase is slowly dripped into ether, and the precipitated solid is filtered and dried to obtain a crude product. Extract with n-hexane and ether for 12h respectively, and finally obtain 0.05g of brown solid CS-7M with a yield of 42%.

[0099] Take 30 mg of the polybenzocarbazole derivative CS-7M obtained by the above reaction and dissolve it in 10 ml of dichloromethane. Add 2 ml of trimethylsilyl bromide under nitrogen protection and stir at room temperature for 12 hours. After the reaction is completed, add 5 ml of methanol to the system to remove excess trimethylsilyl bromide and stir for 3 hours. Concentrate the solution by vacuum distillation, then add sufficient deionized water for precipitation. After the precipitated product is filtered and dried, 20 mg of brown solid is obtained, with a yield of 74%, which is the polybenzocarbazole derivative CS-7. The structural formula is as follows:

[0100]

[0101] Example 8: Synthesis of polybenzocarbazole derivative CS-8

[0102]

[0103] In a two-necked flask, add benzocarbazole phosphate (0.11g, 0.20mmol), tetrakistriphenylphosphine palladium (5mg) and 15mL N,N-dimethylformamide (DMF), stir under nitrogen protection until the solution is clear, then add 2,7-bis(trimethyltinyl)naphtho[1,2-b:5,6-b']dithiophene at room temperature, and heat to reflux for 24h. After the reaction is completed, add 10ml hydrochloric acid solution for post-treatment and extract with chloroform. The organic phase is slowly dripped into ether, and the precipitated solid is filtered and dried to obtain a crude product. Extract with n-hexane and ether for 12h respectively, and finally obtain 0.08g of yellow solid CS-8M with a yield of 62%.

[0104] Take 40 mg of the polybenzocarbazole derivative CS-8M obtained by the above reaction and dissolve it in 20 ml of dichloromethane. Add 3 ml of trimethylsilyl bromide under nitrogen protection and stir at room temperature for 12 hours. After the reaction is completed, add 5 ml of methanol to the system to remove excess trimethylsilyl bromide and stir for 3 hours. Concentrate the solution by vacuum distillation, then add sufficient deionized water for precipitation. After the precipitated product is filtered and dried, 25 mg of brown-black solid is obtained, with a yield of 6%, which is the polybenzocarbazole derivative CS-8. The structural formula is as follows:

[0105]

[0106] Example 9: Synthesis of polybenzocarbazole derivative CB-1

[0107]

[0108] In a two-necked flask, add benzocarbazole phosphate (0.11g, 0.20mmol), tetrakistriphenylphosphine palladium (10mg) and 15mL N,N-dimethylformamide (DMF), stir under nitrogen protection until the solution is clear, then add 1,4-diphenyldiboronic acid pinacol ester (0.07g, 0.20mmol) at room temperature, and heat to reflux for 36h. After the reaction is completed, add enough deionized water and extract with dichloromethane. The organic phase is slowly dripped into n-hexane, and the precipitated solid is filtered and dried to obtain a crude product. Ether extraction for 12h, finally obtain light yellow solid CB-1M 0.05g, yield 49%.

[0109] Take 20 mg of the polybenzocarbazole derivative CB-1M obtained by the above reaction and dissolve it in 15 ml of dichloromethane. Add 2 ml of trimethylsilyl bromide under nitrogen protection and stir at room temperature for 12 hours. After the reaction is completed, add 5 ml of methanol to the system to remove excess trimethylsilyl bromide and stir for 3 hours. Concentrate the solution by vacuum distillation, then add sufficient deionized water for precipitation. After the precipitated product is filtered and dried, 10 mg of brown solid is obtained with a yield of 58%, which is the polybenzocarbazole derivative CB-1. The structural formula is as follows:

[0110]

[0111] Example 10: Synthesis of polybenzocarbazole derivative CB-2

[0112]

[0113] In a two-necked flask, add benzocarbazole substrate (0.11g, 0.20mmol), tetrakistriphenylphosphine palladium (10mg) and 15mL N,N-dimethylformamide (DMF), stir under nitrogen protection until the solution is clear, then add 1,4-diphenyldiboronic acid pinacol ester (0.07g, 0.20mmol) at room temperature, and heat to reflux for 36h. After the reaction is completed, add enough deionized water and extract with dichloromethane. The organic phase is slowly dripped into n-hexane, and the precipitated solid is filtered and dried to obtain a crude product. Ether extraction for 12h, finally obtain light yellow solid CB-2M 0.06g, yield 60%.

[0114] Take 40 mg of the polybenzocarbazole derivative CB-2M obtained by the above reaction and dissolve it in 15 ml of dichloromethane. Add 3 ml of trimethylsilyl bromide under nitrogen protection and stir at room temperature for 12 hours. After the reaction is completed, add 5 ml of methanol to the system to remove excess trimethylsilyl bromide and stir for 3 hours. Concentrate the solution by vacuum distillation, then add sufficient deionized water for precipitation. After the precipitated product is filtered and dried, 23 mg of yellow solid is obtained, with a yield of 65%, which is the polybenzocarbazole derivative CB-2. The structural formula is as follows:

[0115]

[0116] Example 11: Synthesis of polybenzocarbazole derivative CB-3

[0117]

[0118] In a two-necked flask, add benzocarbazole phosphate (0.11 g, 0.20 mmol), tetrakistriphenylphosphine palladium (10 mg) and 15 mL N, N-dimethylformamide (DMF), stir under nitrogen protection until the solution is clear, then add 1,4-bis (4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl) naphthalene (0.08 g, 0.20 mmol) at room temperature, and heat to reflux for 36 h. After the reaction is completed, add enough deionized water and extract with dichloromethane. The organic phase is slowly dripped into n-hexane, and the precipitated solid is filtered and dried to obtain a crude product. Ether extraction for 12 h, finally obtain yellow solid CB-3M 0.07 g, yield 62%.

[0119] Take 40 mg of the polybenzocarbazole derivative CB-3M obtained by the above reaction and dissolve it in 20 ml of dichloromethane. Add 3 ml of trimethylsilyl bromide under nitrogen protection and stir at room temperature for 12 hours. After the reaction is completed, add 5 ml of methanol to the system to remove excess trimethylsilyl bromide and stir for 3 hours. Concentrate the solution by vacuum distillation, then add sufficient deionized water for precipitation. After the precipitated product is filtered and dried, 20 mg of brown solid is obtained with a yield of 54%, which is the polybenzocarbazole derivative CB-3. The structural formula is as follows:

[0120]

[0121] Example 12: Synthesis of polybenzocarbazole derivative CB-4

[0122]

[0123] In a two-necked flask, add benzocarbazole phosphate (0.11 g, 0.20 mmol), tetrakistriphenylphosphine palladium (10 mg) and 15 mL N, N-dimethylformamide (DMF), stir under nitrogen protection until the solution is clear, then add 1,4-bis (4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl) naphthalene (0.08 g, 0.20 mmol) at room temperature, and heat to reflux for 36 h. After the reaction is completed, add enough deionized water and extract with dichloromethane. The organic phase is slowly dripped into n-hexane, and the precipitated solid is filtered and dried to obtain a crude product. Ether extraction for 12 h, finally obtain yellow solid CB-4M 0.07 g, yield 65%.

[0124] Take 40 mg of the polybenzocarbazole derivative CB-4M obtained by the above reaction and dissolve it in 20 ml of dichloromethane. Add 3 ml of trimethylsilyl bromide under nitrogen protection and stir at room temperature for 12 hours. After the reaction is completed, add 5 ml of methanol to the system to remove excess trimethylsilyl bromide and stir for 3 hours. Concentrate the solution by vacuum distillation, then add sufficient deionized water for precipitation. After the precipitated product is filtered and dried, 26 mg of yellow solid is obtained, with a yield of 74%, which is the polybenzocarbazole derivative CB-4. The structural formula is as follows:

[0125]

[0126] Example 13: Synthesis of polybenzocarbazole derivative CB-5

[0127]

[0128] In a two-necked flask, add benzocarbazole phosphate (0.11 g, 0.20 mmol), tetrakistriphenylphosphine palladium (10 mg) and 15 mL N, N-dimethylformamide (DMF), stir under nitrogen protection until the solution is clear, then add 4,4'-biphenyl diboronic acid di(pinacol ester) (0.08 g, 0.20 mmol) at room temperature, and heat to reflux for 36 h. After the reaction is completed, add enough deionized water and extract with dichloromethane. The organic phase is slowly dripped into n-hexane, and the precipitated solid is filtered and dried to obtain a crude product. Ether extraction for 12 h, finally obtain light brown solid CB-5M0.06 g, yield 53%.

[0129] Take 40 mg of the polybenzocarbazole derivative CB-5M obtained by the above reaction and dissolve it in 20 ml of dichloromethane. Add 3 ml of trimethylsilyl bromide under nitrogen protection and stir at room temperature for 12 hours. After the reaction is completed, add 5 ml of methanol to the system to remove excess trimethylsilyl bromide and stir for 3 hours. Concentrate the solution by vacuum distillation, then add sufficient deionized water for precipitation. After the precipitated product is filtered and dried, 26 mg of brown solid is obtained with a yield of 72%, which is the polybenzocarbazole derivative CB-5. The structural formula is as follows:

[0130]

[0131] Example 14: Synthesis of polybenzocarbazole derivative CB-6

[0132]

[0133] In a two-necked bottle, add benzocarbazole phosphate (0.13g, 0.20mmol), tetrakistriphenylphosphine palladium (10mg) and 15mL N,N-dimethylformamide (DMF), stir under nitrogen protection until the solution is clear, then add 4,4'-biphenyl diboronic acid di(pinacol ester) (0.08g, 0.20mmol) at room temperature, and heat to reflux for 36h. After the reaction is completed, add enough deionized water and extract with dichloromethane. The organic phase is slowly dripped into n-hexane, and the precipitated solid is filtered and dried to obtain a crude product. Ether extraction for 12h, finally obtain yellow solid CB-6 0.08g, yield 61%.

[0134] Take 40 mg of the polybenzocarbazole derivative CB-6M obtained by the above reaction and dissolve it in 20 ml of dichloromethane. Add 3 ml of trimethylsilyl bromide under nitrogen protection and stir at room temperature for 12 hours. After the reaction is completed, add 5 ml of methanol to the system to remove excess trimethylsilyl bromide and stir for 3 hours. Concentrate the solution by vacuum distillation, then add sufficient deionized water for precipitation. After the precipitated product is filtered and dried, 29 mg of brown solid is obtained with a yield of 79%, which is the polybenzocarbazole derivative CB-6. The structural formula is as follows:

[0135]

[0136] Example 15: Synthesis of polybenzocarbazole derivative CB-7

[0137]

[0138] In a two-necked bottle, add benzocarbazole phosphate (0.11g, 0.20mmol), tetrakistriphenylphosphine palladium (10mg) and 15mL N,N-dimethylformamide (DMF), stir under nitrogen protection until the solution is clear, then add 2,7-bis(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)naphthalene (0.08g, 0.20mmol) at room temperature, and heat to reflux for 36h. After the reaction is completed, add enough deionized water and extract with dichloromethane. The organic phase is slowly dripped into n-hexane, and the precipitated solid is filtered and dried to obtain a crude product. Ether extraction for 12h, finally obtain yellow solid CB-7M 0.06g, yield 56%.

[0139] Take 40 mg of the polybenzocarbazole derivative CB-7M obtained by the above reaction and dissolve it in 20 ml of dichloromethane. Add 3 ml of trimethylsilyl bromide under nitrogen protection and stir at room temperature for 12 hours. After the reaction is completed, add 5 ml of methanol to the system to remove excess trimethylsilyl bromide and stir for 3 hours. Concentrate the solution by vacuum distillation, then add sufficient deionized water for precipitation. After the precipitated product is filtered and dried, 24 mg of yellow solid is obtained, with a yield of 67%, which is the polybenzocarbazole derivative CB-7. The structural formula is as follows:

[0140]

[0141] Example 16: Preparation of perovskite solar cells based on polybenzocarbazole derivatives

[0142] The polybenzocarbazole derivatives obtained in Examples 1 to 15 were used as hole transport materials to prepare perovskite solar cell devices. The specific preparation process is as follows:

[0143] The polybenzocarbazole derivative was dissolved in DMF to prepare a solution with a concentration of 0.5 mg / ml. 50 μl of the polymer solution was spin-coated on an ITO glass substrate (before spin coating, the ITO glass substrate was ultrasonically cleaned with detergent, deionized water, acetone, and isopropanol for 10 min each, and treated with ultraviolet ozone for 30 min), and then thermally annealed (80°C / 10 min). Subsequently, a perovskite active layer (Cs 0.05 FA 0.85 MA 0.1PbI3), the active layer was thermally annealed (100℃ / 30min), and then 25nm thick C60 and 5nm thick BCP were evaporated, and finally Ag was evaporated as the top electrode.

[0144] The structural formula of BCP is shown below:

[0145]

[0146] Photovoltaic device performance: in white light 1.5G (100mW cm -2 ) irradiation, the device performance is shown in Table 1 below, where V oc represents the open circuit voltage, J sc represents short-circuit current, FF represents fill factor, and PCE represents photoelectric conversion efficiency.

[0147] Example 17: Preparation of organic solar cells based on polybenzocarbazole derivatives

[0148] The polybenzocarbazole derivatives obtained in Examples 1 to 15 were used as hole transport materials to prepare organic solar cell devices. The specific preparation process is as follows:

[0149] The polybenzocarbazole derivative was dissolved in DMF to prepare a solution with a concentration of 0.5 mg / ml. 50 microliters of the polymer solution was spin-coated on an ITO glass substrate (before spin coating, the ITO glass substrate was ultrasonically cleaned with detergent, deionized water, acetone, and isopropanol for 10 minutes each, and treated with ultraviolet ozone for 30 minutes), and then thermally annealed (80°C / 10 minutes). Subsequently, the active layer solution (the donor material and the acceptor material are in the same ratio, PM6:eC9=1:1, solution concentration = 15 mg / mL) was spin-coated on the ITO glass substrate to prepare a photoactive layer. The active layer was thermally annealed for 10 minutes (100°C / 10 minutes), and then PDINN (concentration: 1.0 mg mL -1 The cathode was prepared by evaporating Ag.

[0150] The structures of PM6, eC9 and PDINN are shown below:

[0151]

[0152] Photovoltaic device performance: in white light 1.5G (100mW cm -2 ), the device performance is shown in Table 2 below, where Voc represents open circuit voltage, Jsc represents short circuit current, FF represents fill factor, and PCE represents photoelectric conversion efficiency.

[0153] Table 1 Photovoltaic device performance of Example 16

[0154] Hole transport materials <![CDATA[V oc (V)]]> <![CDATA[J sc (mA / cm 2 )]]> FF(%) PCE(%) CS-1 1.16 24.81 82.8 23.83 CS-2 1.17 24.94 82.5 24.07 CS-3 1.19 24.74 84.3 24.82 CS-4 1.18 23.83 81.9 23.03 CS-5 1.16 24.77 82.6 23.73 CS-6 1.19 23.73 83.8 23.66 CS-7 1.18 25.33 80.7 24.12 CS-8 1.19 25.19 82.8 24.82 CB-1 1.16 24.89 81.4 23.50 CB-2 1.19 25.02 83.3 24.80 CB-3 1.18 24.16 82.3 23.46 CB-4 1.18 24.41 82.8 23.85 CB-5 1.17 24.77 82.6 23.94 CB-6 1.18 24.26 83.4 23.87 CB-7 1.17 25.11 80.9 23.77

[0155] Table 2 Photovoltaic device performance of Example 17

[0156] Hole transport materials <![CDATA[V oc (V)]]> <![CDATA[J sc (mA / cm 2 )]]> FF(%) PCE(%) CS-1 0.85 29.01 77.6 19.13 CS-2 0.83 28.94 78.6 18.87 CS-3 0.84 29.22 78.0 19.14 CS-4 0.83 29.13 78.8 19.05 CS-5 0.84 29.11 78.6 19.22 CS-6 0.85 28.83 77.9 19.08 CS-7 0.85 29.03 78.2 19.29 CS-8 0.85 29.00 79.5 19.59 CB-1 0.84 29.11 78.0 19.07 CB-2 0.85 29.07 79.2 19.57 CB-3 0.85 28.79 79.0 19.33 CB-4 0.84 28.91 78.5 19.06 CB-5 0.84 29.07 78.2 19.09 CB-6 0.84 29.19 77.8 19.07 CB-7 0.83 29.32 78.6 19.12

Claims

1. A polybenzocarbazole derivative, characterized in that: It has a structure as shown in formula (I): Wherein, Ar is an aromatic group; linker is selected from a linear alkyl group having 2 to 8 carbon atoms, a phenyl group or a biphenyl group; and n is the number of repeating units, which is between 5 and 1000.

2. The polybenzocarbazole derivative according to claim 1, characterized in that The Ar is selected from one of the following structures: Among them, R1, R2, and R3 are independently selected from hydrogen atoms, fluorine atoms, chlorine atoms, bromine atoms, aldehyde groups, amino groups, polyether chains, straight-chain or branched alkyl groups with 1 to 50 carbon atoms, alkoxy groups, substituted or unsubstituted halogenated alkyl groups with 1 to 50 carbon atoms, substituted or unsubstituted aryl groups with 1 to 50 carbon atoms, and substituted or unsubstituted heteroaryl groups with 1 to 50 carbon atoms.

3. The polybenzocarbazole derivative according to claim 1, characterized in that The linker is selected from one of the following structures: Wherein, n is the number of repeating units, and its value is between 1 and 4.

4. The method for preparing a polybenzocarbazole derivative according to any one of claims 1 to 3, characterized in that: The following steps are involved: (1) dissolving a halogen-substituted benzocarbazole derivative monomer having a phosphate group in an organic solvent, adding a tin-based or borate-substituted aromatic group monomer, and performing a polymerization reaction under the action of a catalyst to obtain a polybenzocarbazole derivative intermediate; (2) dissolving the polybenzocarbazole derivative intermediate in an organic solvent 2, adding trimethylsilyl bromide to carry out a reaction, and after the reaction is completed, quenching with alcohols and treating the reaction product with a poor solvent to obtain the polybenzocarbazole derivative.

5. The preparation method according to claim 4, characterized in that: The structure of the halogen-substituted benzocarbazole derivative monomer with a phosphate group is shown in formula (II): Wherein, X represents a halogen atom, and linker is a straight-chain alkyl group having 2 to 8 carbon atoms, a phenyl group or a biphenyl group.

6. The preparation method according to claim 4, characterized in that: The structure of the tin-based or borate-substituted aromatic group monomer is shown in formula (III) or formula (IV): Wherein, Ar is an aromatic group; R is independently selected from an alkyl group or an aryl group, and n is the number of R groups, which is 3.

7. The preparation method according to claim 4, characterized in that: In step (1), the molar ratio of the halogen-substituted benzocarbazole derivative monomer with a phosphate group to the aromatic group monomer substituted with a tin group or a borate group is 1:0.2-5; the polymerization reaction conditions are heating under reflux for 12-36 hours; And / or; in step (2), the molar ratio of the polybenzocarbazole derivative intermediate to trimethylsilyl bromide is 1:10-20; and the reaction time is 12-36h.

8. Use of the polybenzocarbazole derivative according to any one of claims 1 to 3 in optoelectronic functional devices.

9. An organic solar cell comprising a cathode layer, a cathode buffer layer, a photoactive layer, an anode buffer layer and an anode layer stacked in sequence, characterized in that: The anode buffer layer contains the polybenzocarbazole derivative described in any one of claims 1 to 3.

10. A perovskite solar cell, comprising a cathode layer, a hole blocking layer, an electron transport layer, a perovskite active layer, an anode modification layer and an anode layer stacked in sequence, characterized in that: The anode modification layer contains the polybenzocarbazole derivative described in any one of claims 1 to 3.

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