A polycarbazole material, a preparation method and application in optoelectronic devices

Abstract

The application discloses a kind of polyphosphoric acid carbazole material and its preparation method and application, belong to material preparation field.The polyphosphoric acid carbazole material provided in the application has better stability, and the good film-forming property and the interaction between macromolecular chains can effectively solve the problems such as poor compactness and easy diffusion of traditional carbazole phosphate small molecules, so as to realize stable optoelectronic devices based on polyphosphoric acid carbazole.The synthesis method of the polyphosphoric acid carbazole is simple and fast, the reaction condition is mild, the obtained polyphosphoric acid carbazole material is dissolved in toluene, chlorobenzene, chloroform, dichloromethane, methanol, ethanol, isopropanol and other single or mixed solvents, and is processed into a thin film by spin coating, blade coating, slot coating, dip coating, spraying and other processes, and then optoelectronic devices based on polyphosphoric acid carbazole material are prepared.The present application has important scientific significance and extremely high industrial value.

Description

Technical Field

[0001] This invention belongs to the field of materials preparation, and more specifically, relates to a polyphosphate carbazole material, its preparation method, and its application. Background Technology

[0002] Carbazole phosphate (PACz) is a hole transport material developed in recent years. It offers the advantage of solution-processability, forming a monolayer on conductive substrates (ITO and FTO). Compared to PTAA-based polytriphenylamine hole transport layer materials, perovskite films exhibit better wettability on PACz, facilitating large-area coating and enabling efficient hole transport in inverted perovskite photovoltaics. Currently, PACz has become a commonly used hole transport material in inverted perovskite solar cells. However, despite its excellent hole transport performance, PACz's density and stability remain challenges. Efficient hole transport requires a dense, uniform monolayer on a conductive substrate, but during solution processing, PACz can locally form multilayers, increasing resistance to hole extraction. Furthermore, PACz can diffuse into the perovskite active layer under photothermal conditions. Furthermore, on some rough conductive substrates, such as FTO, the small molecule carbazole phosphate cannot completely cover the entire conductive substrate, causing direct contact between the perovskite film and the conductive substrate. This situation leads to localized leakage and, moreover, the conductive substrate induces the decomposition of the perovskite, resulting in the degradation of perovskite solar cells (Science 2020, 370, 1300-1309; Nature 2023, Nature https: / / doi.org / 10.1038 / s41586-41023-05992-y; Joule 2020, 4, 850-864; Nature Energy 2023, https: / / doi.org / 10.1038 / s41560-41023-01227-41566). Developing novel hole transport layer materials to address the problems associated with the current small molecule carbazole phosphate is a crucial step in improving the stability of inverted perovskite photovoltaic devices and promoting their industrialization. Summary of the Invention

[0003] The technical problem this invention aims to solve is the high hole resistance, poor coverage, and diffusion issues encountered when applying small carbazole phosphate molecules to conductive substrates. This invention provides a carbazole polyphosphate material with good film-forming properties, excellent stability, and low diffusion resistance. Another technical problem this invention aims to solve is to provide a method for preparing the above-mentioned carbazole polyphosphate material. A further technical problem this invention aims to solve is to provide an application of the above-mentioned carbazole polyphosphate material in organic solar cells and perovskite solar cells.

[0004] During the research process of this patent, it was discovered that by polymerizing small molecule carbazole phosphate to increase its molecular weight, its film-forming properties on the surface of a conductive substrate can be effectively improved, thus forming a stable hole transport layer with a suitable thickness.

[0005] A polyphosphate carbazole material comprising multiple repeating units, the structure of which is as follows:

[0006]

[0007] In the formula, the benzene ring on the carbazole phosphate unit may or may not contain substituents;

[0008] In the polycarbazole polyphosphate structure of this patent, as long as the small molecule carbazole phosphate can be polymerized to a certain extent and the molecular weight is increased, the film-forming properties of the coating after coating can be effectively improved. The number of repeating units in the polymer material can be from 2 to 10,000,000, preferably greater than 5, 8, 10, 15, 20, 25, 30, 50, 80, 100, 200, 500, 1000, 2000, 5000, etc., or it can be a parameter range composed of any integers in this range.

[0009] The polycarbazole polyphosphate used in this patent is polymerized from small molecules. The small molecule carbazole polyphosphate can adopt the structure disclosed in the prior art. In this patent, the molecular weight is increased by polymerizing it. As long as the small molecule carbazole polyphosphate has certain hole transport characteristics, the purpose of this invention can be achieved. Alternatively, it can be modified by some substituents to adjust and improve its performance.

[0010] When substituents are present, the benzene ring contains one or more independent substituents, which are selected from:

[0011] 1) H;

[0012] 2) Halogen groups;

[0013] 3) Cyano group;

[0014] 4) Alkyl groups;

[0015] 5) Aromatic groups;

[0016] 6) Compound cyclic groups;

[0017] The value of n ranges from 1 to 40, and the polymerization site of polyphosphoric acid carbazole is located at any position on the benzene ring. Its molecular weight ranges from 300 to 10,000,000. Here, n can be 1, 2, 3, 5, 10, 15, 20, or any integer within this range. The molecular weight is increased after polymerization, and its value can be greater than 500, 800, 1000, 1500, 2000, 3000, 5000, 8000, 10000, 15000, 20000, 30000, 50000, 100000, 200000, etc., or any integer within this range.

[0018] The alkyl group is selected from (C1-C40) straight-chain alkyl, (C3-C40) branched alkyl or (C3-C40) cycloalkyl.

[0019] The cyclic group is used to cyclically fuse the benzene ring into macrocycles such as naphthalene and anthracene.

[0020] The halogen group is F, Cl, Br or I.

[0021] The aromatic group is selected from one or more of aryl, heteroaryl, aryloxy, heteroaryloxy, arylcarbonyl, heteroarylcarbonyl, arylcarbonyloxy, heteroarylcarbonyloxy, aryloxycarbonyl or heteroaryloxycarbonyl.

[0022] The repeating unit structure is one of the following structural formulas:

[0023]

[0024] Where m ranges from 2 to 10,000,000, and R1, R2, and R3 are H or the substituents mentioned above.

[0025] The polycarbazole phosphate material provided in this patent, with or without substituents, is obtained by polymerizing small-molecule carbazole phosphate and hydrolyzing the ester group. Its polymerization site is at any position on the benzene ring. To achieve the synthesis of this polymeric material, this invention provides the following synthetic approach: polymerization is achieved through a catalytic condensation reaction of carbazole phosphate. In the reaction, halophosphate carbazole can be used for condensation, where the halo group can be at any position on the benzene ring. Furthermore, in this case, some substituent-modified carbazole phosphates can also be used for the reaction. Alternatively, during the condensation reaction, a corresponding halogenated compound can be added to copolymerize with carbazole phosphate, followed by the addition of a halosilane and an alcohol compound to hydrolyze the polycarbazole phosphate into polycarbazole phosphate.

[0026] The preparation method of the above-mentioned polyphosphoric carbazole material includes the following steps:

[0027] Step 1: The halophosphate carbazole is copolymerized in a solvent with or without the addition of other halogenated compounds;

[0028] Step 2: After adding halosilanes and alcohols for hydrolysis, carbazole polyphosphate material is obtained.

[0029] The other halogenated compounds are selected from halogenated aromatic hydrocarbons or halogenated thiophenes, with or without substituents.

[0030] The aromatic group in the haloaromatic hydrocarbon is selected from one or more of aryl, heteroaryl, aryloxy, heteroaryloxy, arylcarbonyl, heteroarylcarbonyl, arylcarbonyloxy, heteroarylcarbonyloxy, aryloxycarbonyl or heteroaryloxycarbonyl.

[0031] The self-polymerization of carbazole halophosphates without the addition of other halo compounds.

[0032] When other halogenated compounds are added, the halophosphate carbazole polymerizes with other halogenated compounds; the mass ratio of phosphate carbazole to halogenated compounds is 1:0.01 to 10.0, the polymerization reaction time is 0.1 to 72 hours, and the reaction temperature is 0 to 300℃.

[0033] The catalyst used in the catalytic polymerization reaction is selected from nickel-based catalysts.

[0034] The phosphate carbazole comprises one or more of the following unit structural formulas:

[0035]

[0036] The value of n ranges from 1 to 40.

[0037] Rx is independently selected from:

[0038] 1) H;

[0039] 2) Halogen groups;

[0040] 3) Cyano group;

[0041] 4) Alkyl groups;

[0042] 5) Aromatic groups;

[0043] 6) Compound cyclic groups;

[0044] The halogen group is F, Cl, Br or I.

[0045] The alkyl group is selected from (C1-C40) straight-chain alkyl, (C3-C40) branched alkyl or (C3-C40) cycloalkyl.

[0046] In the alkyl group, one or more non-adjacent C atoms are optionally surrounded by -O-, -S-, -C(O)-, -C(O-)-O-, -OC(O-), -OC(O)-O-, or -CR 0 =CR 00 - or -C≡C- substitution, where R 0 and R 00 It can be a straight-chain alkyl, branched alkyl, or cycloalkyl group on its own.

[0047] In the alkyl group, one or more H atoms are optionally replaced by F, Cl, Br, I or CN.

[0048] The aromatic group is selected from aryl, heteroaryl, aryloxy, heteroaryloxy, arylcarbonyl, heteroarylcarbonyl, arylcarbonyloxy, heteroarylcarbonyloxy, aryloxycarbonyl or heteroaryloxycarbonyl, and has 4 to 30 ring atoms.

[0049] In one embodiment, polycarbazole phosphate is obtained by catalytic polymerization using carbazole dibromophosphate as a raw material; the polycarbazole phosphate and trimethylbromosilane are reacted in a solvent under stirring, and then excess methanol is added for hydrolysis to obtain polycarbazole phosphate material; the reaction equation is as follows:

[0050]

[0051] In one embodiment, polycarbazole phosphate is obtained by catalytic reaction using carbazole dibromophosphate and aromatic groups as raw materials; polycarbazole phosphate and trimethylbromosilane are reacted in a solvent under stirring, followed by hydrolysis with excess methanol to obtain polycarbazole phosphate material; the reaction equation is as follows:

[0052]

[0053] In the formula, n is an integer not greater than 40, m is an integer from 2 to 10,000,000, and Ar is an aromatic group.

[0054] Application of polyphosphoric carbazole materials in the fabrication of optoelectronic device structures.

[0055] The optoelectronic device structure includes a solar cell, a field-effect transistor, a photodetector, a radiation detector, and a light-emitting diode. The solar cell includes organic solar cells and perovskite solar cells.

[0056] The polyphosphate carbazole material is used as a hole transport layer material in organic solar cells or perovskite solar cells, or as an interface modification on the basis of the original hole transport layer.

[0057] In the aforementioned application, the battery structure is selected from one of the following:

[0058]

[0059] The perovskite light-absorbing layer comprises a metal halide perovskite with the chemical formula ABX3, wherein A includes, but is not limited to, methylamine ions, formamidinium ions, cesium, rubidium, potassium, sodium, ammonium ions, ethylamine, propylamine, butylamine, aniline, benzylamine, phenethylamine, or combinations thereof; B includes lead, tin, cadmium, germanium, zinc, nickel, or combinations thereof; and X is fluorine, chloride, bromine, iodine anions, or combinations thereof.

[0060] Specifically, the solar cell electrode contains one or more of gold, silver, copper, aluminum, carbon, and chromium. The hole transport layer includes PTAA, Spiro-OMeTAD, PEDOT:PSS, NiO, MoO3, V2O5, Poly-TPD, EH44, P3HT, or a combination of these materials. The electron transport layer includes C... 60 A combination of BCP, TiO2, SnO2, PCBM, ICBA, ZnO, ZrAcac, LiF, TPBi, PFN, Nb2O5, or more of the above materials.

[0061] Specifically, perovskite solar cells have a photoelectric conversion efficiency of 1% to 30%.

[0062] Organic solar cells have a photoelectric conversion efficiency of 1% to 20%.

[0063] Beneficial effects

[0064] 1) The polycarbazole polyphosphate polymer material provided by the present invention has better stability and film-forming properties. The interaction between its polymer chains can effectively solve the problems of poor compactness and easy diffusion of traditional carbazole phosphate small molecules, thereby realizing stable optoelectronic devices based on polycarbazole polyphosphate.

[0065] 2) The synthesis method of polycarbazole polyphosphate is simple and rapid, and the reaction conditions are mild. The obtained polycarbazole polyphosphate material is dissolved in single or mixed solvents such as toluene, chlorobenzene, chloroform, dichloromethane, methanol, ethanol, and isopropanol. It is then processed into thin films by processes such as spin coating, blade coating, slot coating, dip coating, and spray coating to prepare optoelectronic devices based on polycarbazole polyphosphate material, including perovskite solar cells, organic solar cells, field-effect transistors, light-emitting diodes, photodetectors, and X-ray detectors.

[0066] 3) This invention has both important scientific significance and extremely high industrial value. Attached Figure Description

[0067] Figure 1 The images show the stacking morphology of small molecule carbazole phosphate (left) and carbazole polyphosphate (right) materials on conductive ITO and the current distribution under conductive atomic force microscopy.

[0068] Figure 2 This is a graph showing the current-voltage curve of a polyphosphoric carbazole perovskite solar cell as a function of annealing temperature.

[0069] Figure 3 This is a graph showing the current-voltage curve of a carbazole phosphate perovskite solar cell as a function of annealing temperature.

[0070] Figure 4 This is a graph showing the current-voltage curve of a polyphosphate carbazole perovskite solar cell as a function of concentration.

[0071] Figure 5 This is a graph showing the current-voltage curve of a carbazole phosphate small molecule perovskite solar cell as a function of concentration.

[0072] Figure 6 This is the current-voltage curve of the best perovskite solar cell with polyphosphoric carbazole on ITO / FTO substrate.

[0073] Figure 7 This is a long-term stability test curve. Detailed Implementation

[0074] Example 1

[0075] 3.25 g of 3,6-dibromocarbazole and 2.1 g of potassium carbonate were dissolved in 20 mL of 1,4-dibromobutane. 0.485 g of tetrabutylammonium bromide was added, followed by 5.2 mL of 50% potassium hydroxide. The mixture was stirred at 60 °C for 12 hours. After cooling to room temperature, the mixture was concentrated under reduced pressure, filtered to obtain the product, and purified by column chromatography to give 4.1 g of 3,6-dibromo-9-(4-bromobutyl)-9H-carbazole (3,6-dibromo-9-(4-bromobutyl)-9-hydro-carbazole), with the following structural formula:

[0076]

[0077] 1 H NMR (400MHz, CDCl3, ppm): 8.15 (d, J=1.9Hz, 2H), 7.55 (dd, J=8.6Hz, 2.0Hz, 2H), 7.25 (d, 2.1Hz 2H),4.30(t,7.3Hz,2H),3.37(t,6.4Hz,2H),2.07–1.99(m,2H),1.91–1.85(m,2H). 13 C NMR (400MHz, CDCl3, ppm): 139.21, 129.21, 123.58, 123.41, 112.25, 110.28, 42.52, 32.84, 30.06.

[0078] Example 2

[0079] 1 g of 3,6-dibromo-9-(4-bromobutyl)-9H-carbazole was dissolved in 10 mL of triethyl phosphite and heated and stirred at 140 °C for 12 hours. The triethyl phosphite was removed by vacuum distillation, and the product was purified by column chromatography to obtain diethyl(4-(3,6-dibromo-9H-carbazol-9-yl)butyl)phosphonate((4-(3,6-dibromo-9H-carbazol-9-yl)butyl)phosphonate), with the following structural formula:

[0080]

[0081] 1 H NMR (400MHz, CDCl3, ppm): 8.12 (d, 2.1Hz, 2H), 7.54 (dd, J = 8.7Hz, 1.9Hz, 2H), 7.25 (d, 8.9H z,2H),4.25(t,J=7.9Hz,2H),3.96–4.06(m,4H),1.61–1.96(m,6H),1.25(t,J=7.1Hz,6H). 13 C NMR (400MHz, CDCl3, ppm): 139.22, 129.13, 123.53, 123.33, 112.15, 110.33, 61.63, 42.68, 26.12, 24.78, 20.46, 16.46.

[0082] Example 3

[0083] 0.8 g Ni(Cod)₂, 0.286 g bipyridine, and 0.23 mL 1,5-cyclooctadiene were dissolved in 10 mL DMF. The mixture was heated and stirred at 80 °C for half an hour. 0.5 g (4-(3,6-dibromo-9H-carbazol-9-yl)butyl)phosphonate ((4-(3,6-dibromo-9H-carbazol-9-yl)butyl)phosphate diethyl phosphate) was dissolved in 10 mL DMF and slowly added dropwise to the reaction mixture. The mixture was stirred at 80 °C for 24 hours. After the reaction was completed and cooled to room temperature, dilute hydrochloric acid was slowly added dropwise while stirring until the mixture dissolved and became a transparent green solution. The suspended solid was filtered to obtain the final product, a brown polyphosphate carbazole powder with the following structural formula:

[0084]

[0085] Example 4

[0086] 0.12 g of polyphosphate carbazole was dissolved in 20 mL of dichloromethane, and 2 mL of 0.1 g / mL trimethylbromosilane was added dropwise. The mixture was stirred at room temperature for 24 hours. After the reaction was completed, excess methanol was added dropwise to remove excess trimethylbromosilane. The solution was concentrated by vacuum distillation, precipitated in diethyl ether, and filtered and washed with diethyl ether. The final product was polyphosphate carbazole powder with a number average molecular weight of approximately 1800 and a weight average molecular weight of approximately 2300. The structural formula is as follows:

[0087]

[0088] Example 5

[0089] ITO conductive glass was treated in a UV ozone cleaner for 15 minutes, and then different concentrations (0.3 mg / ml to 3 mg / ml) of small molecule carbazole phosphate or polycarbazole phosphate were coated onto it. Annealing was then performed at 100°C, 150°C, and 200°C, respectively. Subsequently, MA was coated onto it. 0.7 FA 0.3 A 25nm C200PbI3 perovskite polycrystalline thin film was deposited on its surface after thermal annealing. 60 The perovskite solar cell was fabricated using a 5nm BCP and a 100nm copper electrode.

[0090] Comparative Experiment: In order to compare the performance of polycarbazole, the following small molecule carbazole phosphate (Me-4PACz) was used for comparison, and the carbazole phosphate prepared in Example 2 was used.

[0091]

[0092] Small molecule carbazole phosphate (Me-4PACz) and polycarbazole polyphosphate (Poly-4PACz) were coated onto ITO conductive glass, such as... Figure 1 As shown, small-molecule carbazole phosphate exhibits poor coverage on ITO, with localized multilayer stacking, resulting in lower current and higher resistance during conductive atomic force microscopy (AFM). In contrast, polycarbazole phosphate demonstrates excellent coverage and film-forming properties on ITO, exhibiting higher current and lower resistance during AFM, which is beneficial for hole extraction.

[0093] The results of the study on the annealing temperature of small molecule carbazole phosphate (Me-4PACz) or polycarbazole phosphate (Poly-PACz) are as follows: Figure 2 , Figure 3 As shown in Table 1, Figure 2 This is a graph showing the current-voltage curve of a carbazole polyphosphate perovskite solar cell as a function of annealing temperature. Figure 3This is a graph showing the current-voltage curve of a carbazole phosphate small molecule perovskite solar cell as a function of annealing temperature. It can be clearly seen that small molecule carbazole phosphate is more sensitive to annealing temperature, while polycarbazole polyphosphate material is not sensitive to annealing temperature.

[0094] Table 1. Parameters of polycarbazole phosphate and carbazole phosphate small molecule perovskite solar cells at different annealing temperatures. Results of studies on the concentration / thickness of small molecule carbazole phosphate or polycarbazole phosphate, as follows: Figure 4 , Figure 5 As shown in Table 2, Figure 4 This is a graph showing the current-voltage curve of a polyphosphate carbazole perovskite solar cell as a function of concentration. Figure 5 This is a graph showing the current-voltage curve of a carbazole phosphate small molecule perovskite solar cell as a function of concentration. It can be clearly seen that small molecule carbazole phosphate is more sensitive to concentration / thickness, while polycarbazole polyphosphate material is not sensitive to concentration / thickness.

[0095] Table 2. Parameters of small molecule perovskite solar cells with different concentrations of polycarbazole polyphosphate and carbazole phosphate. It is evident that the perovskite solar cell based on carbazole polyphosphate can achieve a photoelectric conversion efficiency of 22.64%, exceeding that of the control group based on small molecule carbazole polyphosphate. Furthermore, the perovskite solar cell based on carbazole polyphosphate is insensitive to both the concentration of carbazole polyphosphate and the annealing temperature.

[0096] Example 6

[0097] The ITO conductive glass was treated in an ultraviolet ozone cleaner for 15 minutes, then a 5-10 nm thick layer of polyphosphate carbazole was spin-coated onto it, followed by a PM6:Y6 active layer, and finally a 5 nm PDINN was spin-coated and a 100 nm silver electrode was deposited to complete the fabrication of the organic solar cell.

[0098] Example 7

[0099] FTO conductive glass was treated in a UV ozone cleaner for 15 minutes, then coated with 1 mg / ml carbazole polyphosphate and annealed at 150°C. Subsequently, MA was coated. 0.7 FA 0.3 A 25nm C200PbI3 perovskite polycrystalline thin film was deposited on its surface after thermal annealing. 60 The perovskite solar cell was fabricated using a 5nm BCP and a 100nm copper electrode. Figure 6Table 3 shows the current-voltage curves of the best perovskite solar cells using carbazole polyphosphate on ITO / FTO substrates. The parameters of the carbazole polyphosphate perovskite solar cell devices are based on ITO and FTO. It is clear that carbazole polyphosphate achieves good photoelectric conversion efficiency on both ITO and FTO substrates.

[0100] Table 3. Parameters of polycarbazole perovskite solar cell devices based on ITO and FTO.

[0101]

[0102]

[0103] Example 8

[0104] Perovskite solar cells based on small-molecule carbazole phosphate (Me-4PACz) and polycarbazole polyphosphate (Poly-4PACz) were encapsulated and placed under a solar simulator for stability testing at the maximum power point of the solar cells. After more than 100 hours of testing (…),… Figure 7 Perovskite solar cells based on carbazole polyphosphate did not show significant efficiency degradation, while perovskite solar cells based on small carbazole phosphate molecules experienced severe degradation, indicating that carbazole polyphosphate materials have better light stability than small carbazole phosphate molecules.

Claims

1. The application of polycarbazole polyphosphate material in the hole transport layer of optoelectronic device structure, wherein the polycarbazole polyphosphate material comprises multiple repeating units, characterized in that, The repeating unit structure is as follows: ； In the formula, the benzene ring on the carbazole phosphate unit may or may not contain substituents; When substituents are present, the benzene ring contains one or more independent substituents, which are selected from: 1）H； 2) Halogen groups; 3) Cyano group; 4) Alkyl groups; 5) Aromatic groups; 6) Compound cyclic groups; The value of n ranges from 1 to 40, the polymerization site of polyphosphoric carbazole is at any position on the benzene ring, and its molecular weight ranges from 300 to 10,000,000. The alkyl group is selected from (C1-C40) straight-chain alkyl, (C3-C40) branched alkyl, or (C3-C40) cycloalkyl; the fused cyclic group is used to fused the benzene ring to naphthalene or anthracene; the halogen group is F, Cl, Br, or I; the aromatic group is selected from one or more of aryl, heteroaryl, aryloxy, heteroaryloxy, arylcarbonyl, heteroarylcarbonyl, arylcarbonyloxy, heteroarylcarbonyloxy, aryloxycarbonyl, or heteroaryloxycarbonyl; the number of repeating units is 2-10,000,000.

2. The application according to claim 1, characterized in that, The optoelectronic device structure includes a solar cell, a field-effect transistor, a photodetector, a radiation detector, and a light-emitting diode. The solar cell includes organic solar cells and perovskite solar cells.

3. The application according to claim 2, characterized in that, The polyphosphate carbazole material is used as a hole transport layer material in organic solar cells or perovskite solar cells.

4. The application according to claim 2, characterized in that, The structure of a solar cell is selected from one of the following: 。 5. The application according to claim 1, characterized in that, The repeating unit structure is one of the following structural formulas: ; Where m ranges from 2 to 10,000,000.

6. The application according to claim 1, characterized in that, The conductive substrate is FTO or ITO.

7. The application according to claim 1, characterized in that, The preparation method of polycarbazole polyphosphate material includes the following steps: Step 1: The halophosphate carbazole undergoes self-polymerization in a solvent; Step 2: After adding halosilanes and alcohols for hydrolysis, carbazole polyphosphate material is obtained.

8. The application according to claim 7, characterized in that, The phosphate carbazole in the halophosphate carbazole comprises one or more of the following unit structural formulas: ； The value of n ranges from 1 to 40; Rx is independently selected from: 1）H； 2) Halogen groups; 3) Cyano group; 4) Alkyl groups; 5) Aromatic groups; 6) Compound cyclic groups; The halogen group is F, Cl, Br or I; The alkyl group is selected from (C1-C40) straight-chain alkyl, (C3-C40) branched alkyl, or (C3-C40) cycloalkyl; The aromatic group is selected from aryl, heteroaryl, aryloxy, heteroaryloxy, arylcarbonyl, heteroarylcarbonyl, arylcarbonyloxy, heteroarylcarbonyloxy, aryloxycarbonyl or heteroaryloxycarbonyl, and has 4 to 30 ring atoms.

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