A boron-amine complex monomer with strong charge separation, a boron-amine conjugated polymer and a preparation method and application thereof

Abstract

The application discloses a boron-amine complex monomer with strong charge separation, a boron-amine conjugated polymer and a preparation method and application thereof. In view of the problem that most existing organic catalyst structural units are not completely charge-separated, a boron-amine complex monomer with strong charge separation is designed, and a boron-amine conjugated polymer catalyst with strong charge separation is prepared by using a boron-tin exchange reaction as a polymerization means. The boron-amine complex monomer is prepared from BBr3, (5-bromothiophene-2-yl)trimethylstannane and a pyridine compound as raw materials. The boron-amine conjugated polymer is prepared from the boron-amine complex monomer and 2,5-bis(trimethylstannyl)thiophene as raw materials by a boron-tin exchange polymerization reaction. The boron-amine conjugated polymer prepared by the application has high catalytic activity and efficiency, and the preparation method is simple, and the boron-amine conjugated polymer has a good application prospect in the field of photocatalytic hydrogen production.

Description

Technical Field

[0001] This invention relates to a boron-amine complex monomer with strong charge separation, a boron-amine conjugated polymer, its preparation method and application, belonging to the field of photocatalytic water hydrogen production technology. Background Technology

[0002] Currently, the large-scale use of fossil fuels has led to severe energy shortages and environmental pollution, prompting a strong search for clean and renewable energy sources. Developing clean and efficient hydrogen energy is a sustainable and promising path. Inspired by natural photosynthesis, scientists are using semiconductor photocatalysts to split water into hydrogen and oxygen under visible light. This strategy can directly convert solar energy into chemical energy.

[0003] Since 1972, Fujishima and Honda [1] Following the use of TiO2 as a photocatalyst for photocatalytic water production of hydrogen, various inorganic semiconductor photocatalysts have been developed. Most of these catalysts are based on d... 0 d 10 Metal oxides, sulfides, and nitrides, etc. [2] However, inorganic photocatalysts have inherent drawbacks. [3-4] For example, they have a large energy band gap (>3.0 eV), poor solar energy utilization (most can only absorb ultraviolet light), and low solar energy conversion efficiency, making fine-tuning difficult. Among the currently developed photocatalyst libraries, organic conjugated polymers... [5] As a new type of photocatalyst, it possesses unique advantages such as sufficient light absorption efficiency, excellent stability, tunable electronic properties, and economic applicability. The exploration of photocatalytically active organic conjugated polymers can be traced back to 1985. [6] However, the photocatalytic efficiency, especially in the visible light region, is disappointing. In the past decade, organic conjugated polymers have made significant progress in visible light-driven water splitting, with various organic photocatalysts developed, primarily including graphitic carbon nitride polymers. [7-8] (g-C3N4), linear conjugated polymer [9-10] (CPs), conjugated microporous polymers [11-13] (CMPs), covalent organic frameworks [14-15] (COFs), covalent triazine framework [16-17] (CTFs) and polymer dots

[18] wait.

[0004] Most commonly used catalyst structural units have incomplete charge separation and are planar molecules. Generally, when light irradiates a catalyst molecule, photons are absorbed by the catalyst, generating electrons and holes. As these electrons and holes migrate to the surface, water produces hydrogen and oxygen at the electron and hole sites, respectively. However, incomplete separation of the LUMO and HOMO in the photogenerated electrons and holes can easily lead to recombination and annihilation of electrons and holes, resulting in significant energy loss. Furthermore, electron-hole recombination and annihilation occur faster than the formation and migration of free electrons and holes, which is extremely detrimental to achieving high photocatalytic activity and efficiency. To achieve efficient photogenerated electron and hole separation, researchers currently employ a primary strategy in catalyst design: introducing strongly electron-withdrawing acceptor functional groups into the structure to pull electrons from the conjugated framework and achieve charge separation. Based on this, we designed a class of boron-amine complex monomers with strong charge separation; currently, there are no reports on this type of compound. In our previous research, we used boron-tin exchange reaction as a polymerization method to prepare a series of novel triarylboron conjugated polymer porous materials. Based on the same polymerization method, we used boron-amine complex monomers to prepare boron-amine conjugated polymer catalysts with strong charge separation, which is beneficial to achieving high photocatalytic activity and high efficiency, and has important significance in the field of photocatalytic hydrogen production.

[0005] References:

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[0017] 12.Yang,C.;Ma,B.;Zhang,L.;Lin,S.;Ghasimi,S.;Landfester,K.;Zhang,K.;Wang,X.Molecular Engineering of Conjugated Polybenzothiadiazoles for EnhancedHydrogen Production by Photosynthesis.Angew.Chem.,Int.Ed.2016,55,9202-9206.

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[0021] 16. Schwinghammer, K.; Hug, S.; Mesch, MB; Senker, J.; Lotsch, BVPhenyl-Triazine Oligomers for Light-Driven Hydrogen Evolution. Energy Environ. Sci. 2015, 8, 3345-3353.

[0022] 17. Wang, K.; Yang, L.-M.; Wang,

[0023] 18. Wang, L.; Fernandez-Teran, R.; Zhang, L.; Fernandes, DLA; Tian, ​​L.; Chen, H.; Tian, ​​H. Organic Polymer Dots as Photocatalysts for Visible Light-Driven Hydrogen Generation. Angew. Chem., Int. Ed. 2016, 55, 12306-12310. Summary of the Invention

[0024] The technical problem solved by this invention is that most organic catalyst structural units have incomplete charge separation, which is not conducive to improving photocatalytic activity and efficiency.

[0025] To address the aforementioned technical problems, this invention provides a boron-amine complex monomer with strong charge separation, which is any one of BN3, BN4, BN6, and BN9 shown below:

[0026]

[0027] The present invention also provides a method for preparing the above-mentioned boron-amine complex monomer with strong charge separation, comprising the following steps:

[0028]

[0029] Step 1: Dissolve BBr3 and (5-bromothiophen-2-yl)trimethylstannane in a benzene solvent and react them under an inert atmosphere to prepare intermediate A;

[0030] Step 2: Intermediate A, pyridine compounds, and benzene organic solvents are reacted under an inert atmosphere. After the reaction is complete, the resulting mixture is purified after removing the solvent to obtain boron-amine complex monomers. Among them, boron-amine complex monomer BN3 is prepared from intermediate A and pyridine, boron-amine complex monomer BN4 is prepared from intermediate A, 4-bromopyridine, and triethylamine hydrochloride, boron-amine complex monomer BN6 is prepared from intermediate A and 4,4'-bipyridine, and boron-amine complex monomer BN9 is prepared from intermediate A and 1,3,5-tris(4-pyridyl)benzene.

[0031] The chemical structural formula of 4,4'-bipyridine is as follows:

[0032]

[0033] The chemical structural formula of 1,3,5-tris(4-pyridyl)benzene is as follows:

[0034]

[0035] Preferably, the benzene-based organic solvent in steps 1 and 2 is at least one of toluene, xylene, and chlorobenzene.

[0036] Preferably, in step 1, the molar ratio of BBr3 to (5-bromothiophene-2-yl)trimethyltinane is 1:3 to 3.5, and the reaction conditions are: reacting at 100 to 150°C for 2 to 4 days.

[0037] Preferably, the reaction conditions in step 2 are: reacting at room temperature for 2 to 4 days; the purification in step 2 is performed by column chromatography.

[0038] The present invention also provides a boron-amine conjugated polymer with strong charge separation, wherein the boron-amine conjugated polymer is prepared by boron-tin exchange polymerization reaction using the above-mentioned boron-amine complex monomer and 2,5-bis(trimethyltinyl)thiophene as raw materials, and has the structural units shown in Formula I, Formula II, Formula III or Formula IV:

[0039]

[0040] This invention also provides a method for preparing the above-mentioned boron-amine conjugated polymer with strong charge separation, the chemical reaction formula of which is shown below:

[0041]

[0042] Includes the following steps:

[0043] Boron-amine complex monomer, 2,5-bis(trimethyltinyl)thiophene, organopalladium catalyst, organophosphorus ligand and benzene-based organic solvent were heated and reacted under an inert atmosphere for a period of time in a certain feed ratio to produce a precipitate. After the reaction was completed, the precipitate was washed with a haloalkane solvent under inert conditions and filtered to obtain a solid product. The obtained solid product was dried under vacuum to obtain the corresponding conjugated polymer containing boron-nitrogen structure.

[0044] The conjugated polymer containing the structural unit shown in Formula I is prepared by reacting boron-amine complex monomer BN3 with 2,5-bis(trimethyltinyl)thiophene.

[0045] The conjugated polymer containing the structural unit shown in Formula II is prepared by reacting the boron-amine complex monomer BN4 with 2,5-bis(trimethyltinyl)thiophene.

[0046] The conjugated polymer containing the structural unit shown in Formula III is prepared by reacting the boron-amine complex monomer BN6 with 2,5-bis(trimethyltinyl)thiophene.

[0047] The conjugated polymer containing the structural unit shown in Formula IV is prepared by reacting the boron-amine complex monomer BN9 with 2,5-bis(trimethyltinyl)thiophene.

[0048] Preferably, the organopalladium catalyst is tris(dibenzylacetone)dipalladium, the organophosphorus ligand is tris(o-methylphenyl)phosphine, the benzene-based organic solvent is at least one of toluene, xylene, and chlorobenzene, and the chlorinated hydrocarbon solvent is dichloromethane and / or chloroform.

[0049] Preferably, the boron-amine complex monomer and 2,5-bis-(trimethyltinyl)thiophene are fed in a ratio of 1:1, where the molar ratio of bromine atoms in the boron-amine complex monomer to trimethyltin in the 2,5-bis-(trimethyltinyl)thiophene is 1:1.

[0050] Preferably, the organopalladium catalyst is fed at 5-15% of the molar amount of the boron-amine complex monomer; and the organophosphorus ligand is fed at 20-60% of the molar amount of the boron-amine complex monomer.

[0051] Preferably, the heating reaction is carried out at a temperature of 80–100°C for a duration of 36–60 h.

[0052] Preferably, the halogenated hydrocarbon solvent is a dehydrated and deoxygenated solvent.

[0053] The present invention also provides the application of the above-mentioned boron-amine conjugated polymer with strong charge separation in photocatalytic hydrogen production.

[0054] Compared with the prior art, the present invention has the following advantages:

[0055] 1. This invention addresses the problem that most existing organic catalyst structural units have incomplete charge separation by designing a class of boron-amine complex monomers with strong charge separation, and uses boron-tin exchange reaction as a polymerization method to prepare a class of boron-amine conjugated polymer catalysts with strong charge separation, thus overcoming the problems of incomplete charge separation and low photocatalytic activity and efficiency of most existing organic catalyst structural units.

[0056] 2. The boron-amine conjugated polymer of the present invention has high catalytic activity and efficiency, and the preparation method is simple, showing good application prospects in the field of photocatalytic hydrogen production. Attached Figure Description

[0057] Figure 1 The infrared (IR) spectrum of polymer PBN-3 prepared in Example 1;

[0058] Figure 2 The infrared (IR) spectrum of polymer PBN-4 prepared in Example 2;

[0059] Figure 3 The infrared (IR) spectrum of polymer PBN-6 prepared in Example 3;

[0060] Figure 4 The charge separation of the template molecule is shown.

[0061] Figure 5 This is the hydrogen production curve from photocatalytic hydrolysis. Detailed Implementation

[0062] To make the present invention more apparent and understandable, preferred embodiments are described in detail below with reference to the accompanying drawings.

[0063] Example 1

[0064] A boron-amine complex monomer with strong charge separation, tris(5-bromothiophene-2-yl)boron-pyridine complex, designated BN3, has the chemical formula (C4H2BrS)3B·C5H5N and its structure is as follows:

[0065]

[0066] The synthetic route and steps are as follows:

[0067]

[0068] In a Schlenk tube, BBr3 (0.57 g, 2.26 mmol) was first added, followed by 5 mL of toluene. The compound (5-bromothiophene-2-yl)trimethylstanane (2.43 g, 7.46 mmol) was dissolved in toluene and slowly added dropwise until the total solvent volume reached 20 mL. The Schlenk tube was then transferred to an oil bath, and the mixture was stirred at 120 °C for 3 days under nitrogen protection. After the reaction was complete, the Schlenk tube was cooled and transferred to a glove box for vacuum drying. 0.94 mL of pyridine was added, followed by approximately 10 mL of toluene, and the mixture was reacted at room temperature in a glove box for three days. After the reaction was complete, the solvent was removed by rotary evaporation, and the residue was purified by silica gel column chromatography using petroleum ether and dichloromethane (1:1). Finally, 0.97 g of a white solid was obtained. 1 H NMR (400MHz, CDCl3): δ8.63-8.55 (m, 2H), 8.13 (t, J=7.6Hz, 1H), 7.63 (t, J=7.0Hz, 2H), 7.00 (d, J=3.6Hz, 3H), 6.72 (d, J=3.6Hz, 3H); 13 C NMR (101MHz, CDCl3): δ146.80, 141.80, 132.07, 130.60, 125.60, 113.56; 11 B NMR (128MHz, CDCl3): δ-1.43ppm.

[0069] Example 2

[0070] A boron-amine complex monomer with strong charge separation, tris(5-bromothiophene-2-yl)boron-4-bromopyridine complex, designated BN4, has the chemical formula (C4H2BrS)3B·C5H4BrN and its structural formula is as follows:

[0071]

[0072] The synthetic route and steps are as follows:

[0073]

[0074] The synthesis of compound BN4 involved two steps: The first step was the preparation of 4-bromopyridine. In a 100 mL flask, 4-bromopyridine hydrochloride (2.4 g, 12.3 mmol), triethylamine (2.6 mL, 18.7 mmol), and toluene (50 mL) were added sequentially, and the mixture was stirred at room temperature for 12 h. The second step was the preparation of compound BN4. In a Schlenk tube, BBr3 (0.61 g, 2.44 mmol) was added first, followed by 5 mL of toluene. Then, (5-bromothiophene-2-yl)trimethylstanane (2.63 g, 8.07 mmol) was dissolved in toluene and slowly added dropwise until the total solvent volume reached 20 mL. The Schlenk tube was then transferred to an oil bath, and the side arm was protected with nitrogen and stirred at 120 °C for 3 days. After the reaction was complete, the Schlenk tube was cooled and transferred to a glove box for vacuum drying. After adding a mixture of 4-bromopyridine and triethylamine hydrochloride, approximately 10 mL of toluene was added, and the mixture was reacted at room temperature in a glove box for three days. After the reaction was complete, the solvent was removed by rotary evaporation, and the residue was purified by silica gel column chromatography using petroleum ether and dichloromethane (1:1). A white solid of 1.08 g was finally obtained. 1 HNMR (400MHz, CDCl3): δ8.39 (d, J=6.9Hz, 2H), 7.76 (d, J=6.9Hz, 2H), 7.01 (d, J=3.6Hz, 3H), 6.73 (d, J=3.5Hz, 3H); 13 C NMR (101MHz, CDCl3): δ147.17, 139.92, 132.25, 130.69, 129.29, 113.86ppm; 11 B NMR (128MHz, CDCl3): δ-1.12ppm.

[0075] Example 3

[0076] A boron-amine complex monomer with strong charge separation, tris(5-bromothiophene-2-yl)boron-4,4'-bipyridine complex, designated BN6, has the chemical formula (C4H2BrS)3B·NC5H4-C5H4N·B(C4H2BrS)3, and its structural formula is as follows:

[0077]

[0078] The synthetic route and steps are as follows:

[0079]

[0080] The synthesis of compound BN6 was the same as that of BN3 (Example 1). The reactants were: BBr3 (0.47 g, 1.86 mmol), (5-bromothiophene-2-yl)trimethylstanane (2.0 g, 6.14 mmol), 4,4'-bipyridine (0.14 g, 0.87 mmol), and 20 mL of toluene. A yellow solid of 0.85 g was obtained. 1 H NMR (400MHz, CDCl3): δ8.81 (d, J=6.9Hz, 4H), 7.85 (d, J=6.3Hz, 4H), 7.04 (d, J=3.6Hz, 6H), 6.81 (6H); 13 C NMR (101MHz, D-Acetone): δ147.65, 146.44, 132.11, 130.77, 125.05, 112.74ppm; 11 B NMR (128MHz, D-Acetone): δ-1.42ppm.

[0081] Example 4

[0082] A boron-amine conjugated polymer with strong charge separation, denoted as PBN-3, has the basic structural unit shown in Formula I:

[0083]

[0084] The synthetic route and steps are as follows:

[0085]

[0086] In a Schlenk tube, the boron-amine complex monomers BN3 (0.3 g, 0.52 mmol), 2,5-bis(trimethyltinyl)thiophene (0.32 g, 0.78 mmol), tris(dibenzylacetone)palladium (Pd2(dba)3, 0.034 g, 0.037 mmol), and tris(o-methylphenyl)phosphine (P(o-tol)3 (0.056 g, 0.18 mmol) were added sequentially, followed by the addition of 8 mL of toluene. The mixture was stirred in an oil bath at 90 °C for 48 h. After the reaction was complete, the Schlenk tube was cooled and transferred to a glove box. The solid was repeatedly washed with dehydrated and deoxygenated dichloromethane in the glove box and filtered through a sintered glass funnel. Finally, the solid was transferred to a vial and vacuumed for 4 h to obtain 190.0 mg of a brown solid, which was the boron-amine conjugated polymer PBN-3. 11 B MAS SSNMR (400MHz): δ (iso )-2.2ppm. IR:C-Bstretching signal:1035cm -1 C = C - stretching: 1490cm-1 BN stretching: 1412cm -1 IR spectrum as shown Figure 1 As shown.

[0087] Example 5

[0088] A boron-amine conjugated polymer with strong charge separation, denoted as PBN-4, has the basic structural unit shown in Formula II:

[0089]

[0090] The synthetic route and steps are as follows:

[0091]

[0092] The synthesis method of the conjugated polymer PBN-4 is the same as that of PBN-3 (Example 4). The reactants were: boron-amine complex monomer BN4 (0.3 g, 0.46 mmol), 2,5-bis(trimethyltinyl)thiophene (0.38 g, 0.92 mmol), tris(dibenzylacetone)palladium (0.03 g, 0.033 mmol), and tris(o-methylphenyl)phosphine (0.049 g, 0.16 mmol), and 8 mL of toluene. Finally, 223.0 mg of an orange-red solid was obtained, which was the boron-amine conjugated polymer PBN-4. 11 B MAS SSNMR(400MHz)δ (iso) -5.6ppm. IR:CB stretching signal:1039cm -1 C = C stretching: 1495cm -1 BN stretching: 1416cm -1 IR spectrum as follows Figure 2 As shown.

[0093] Example 6

[0094] A boron-amine conjugated polymer with strong charge separation, denoted as PBN-6, has the basic structural unit shown in Formula III:

[0095]

[0096] The synthetic route and steps are as follows:

[0097]

[0098] The synthesis of compound PBN-6 was the same as that of PBN-3 (Example 4). Feed: Boron-amine complex monomer BN6 (0.3 g, 0.26 mmol), 2,5-bis(trimethyltinyl)thiophene (0.32 g, 0.78 mmol), tris(dibenzylacetone)palladium (0.024 g, 0.026 mmol), and tris(o-methylphenyl)phosphine (0.04 g, 0.13 mmol), and 8 mL of toluene. A final yield of 252.0 mg of orange-red solid was obtained, which was the boron-amine conjugated polymer PBN-6. 11B MAS SSNMR (400 MHz): δ(iso) -1.7 ppm. IR: C-B stretching signal: 1038 cm⁻¹ -1 -C = C - stretching: 1493cm -1 BN stretching: 1415cm -1 IR spectrum as shown Figure 3 As shown.

[0099] Application Examples

[0100] Theoretical calculations study charge separation:

[0101] We used density functional theory (DFT) in Gaussian software to study the charge separation properties of the template molecule. First, we optimized the molecular structure using DFT. After obtaining the optimized configuration, we calculated the frontier molecular orbitals of the molecule using time-dependent density functional theory (TD-DFT). Figure 4 As shown, the highest occupied orbital (HOMO) and the lowest unoccupied orbital (LUMO) exhibit significant charge separation characteristics.

[0102] Photocatalytic water splitting for hydrogen production (using PBN-3 prepared in Example 4 as an example):

[0103] 5 mg of PBN-3 powder was added to 100 mL of 0.1 M ascorbic acid aqueous solution. The mixture was sonicated for 30 minutes to obtain a well-dispersed suspension. 3 wt% Pt was used as a co-catalyst. The resulting suspension was transferred to a top-irradiated two-necked Pyrex reaction vessel connected to a closed gas system. The reaction mixture was evacuated several times to ensure complete removal of air before the reaction. Irradiation was performed using a 300 W xenon lamp (PLS-SXE300 / 300UV) with a 400 nm cutoff filter. The photocatalytic hydrogen production duration was 7 hours. Hydrogen was released from the system and analyzed hourly using an automated online trace gas analysis system (Labsolar-6A) with nitrogen as the carrier gas, yielding the following results: Figure 5 The hydrogen production curve shown indicates a calculated hydrogen production rate of 18 μmol / g. -1 h -1 .

[0104] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any form or substance. It should be noted that those skilled in the art can make several improvements and additions without departing from the present invention, and these improvements and additions should also be considered within the scope of protection of the present invention.

Claims

1. A boron-amine complex monomer with strong charge separation, characterized in that, For any one of BN3, BN4, BN6 and BN9 shown below:

2. The method for preparing the boron-amine complex monomer with strong charge separation as described in claim 1, characterized in that, Includes the following steps: Step 1: Dissolve BBr3 and (5-bromothiophen-2-yl)trimethyltinane in a benzene solvent and react them under an inert atmosphere to prepare intermediate A; Step 2: Intermediate A, pyridine compounds, and benzene organic solvents are reacted under an inert atmosphere. After the reaction is complete, the resulting mixture is purified after removing the solvent to obtain boron-amine complex monomers. Among them, boron-amine complex monomer BN3 is prepared from intermediate A and pyridine, boron-amine complex monomer BN4 is prepared from intermediate A, 4-bromopyridine, and triethylamine hydrochloride, boron-amine complex monomer BN6 is prepared from intermediate A and 4,4'-bipyridine, and boron-amine complex monomer BN9 is prepared from intermediate A and 1,3,5-tris(4-pyridyl)benzene.

3. A boron-amine conjugated polymer with strong charge separation, characterized in that, The boron-amine conjugated polymer is prepared using the boron-amine complex monomer of claim 1 and 2,5-bis(trimethyltinyl)thiophene as raw materials, and has the structural units shown in Formula I, Formula II, Formula III or Formula IV:

4. The method for preparing the boron-amine conjugated polymer with strong charge separation as described in claim 3, characterized in that, The chemical reaction formula is shown below: Includes the following steps: Boron-amine complex monomer, 2,5-bis(trimethyltinyl)thiophene, organopalladium catalyst, organophosphorus ligand and benzene-based organic solvent were heated and reacted under an inert atmosphere for a period of time in a certain feed ratio to produce a precipitate. After the reaction was completed, the precipitate was washed with a haloalkane solvent under inert conditions and filtered to obtain a solid product. The obtained solid product was dried under vacuum to obtain the corresponding boron-amine conjugated polymer. The conjugated polymer containing the structural unit shown in Formula I is prepared by reacting boron-amine complex monomer BN3 with 2,5-bis(trimethyltinyl)thiophene. The conjugated polymer containing the structural unit shown in Formula II is prepared by reacting the boron-amine complex monomer BN4 with 2,5-bis(trimethyltinyl)thiophene. The conjugated polymer containing the structural unit shown in Formula III is prepared by reacting the boron-amine complex monomer BN6 with 2,5-bis(trimethyltinyl)thiophene. The conjugated polymer containing the structural unit shown in Formula IV is prepared by reacting the boron-amine complex monomer BN9 with 2,5-bis(trimethyltinyl)thiophene.

5. The method for preparing the boron-amine conjugated polymer with strong charge separation as described in claim 4, characterized in that, The organopalladium catalyst is tris(dibenzylacetone)dipalladium, the organophosphorus ligand is tris(o-methylphenyl)phosphine, the benzene-based organic solvent is at least one of toluene, xylene, and chlorobenzene, and the halogenated hydrocarbon solvent is dichloromethane and / or chloroform.

6. The method for preparing the boron-amine conjugated polymer with strong charge separation as described in claim 4, characterized in that, The boron-amine complex monomer and 2,5-bis(trimethyltinyl)thiophene are fed in a ratio of 1:1, where the molar ratio of bromine atoms in the boron-amine complex monomer to trimethyltin in the 2,5-bis(trimethyltinyl)thiophene is bromine atoms in the boron-amine complex monomer and trimethyltin in the 2,5-bis(trimethyltinyl)thiophene.

7. The method for preparing the boron-amine conjugated polymer with strong charge separation as described in claim 4, characterized in that, The organopalladium catalyst is fed at 5-15% of the molar amount of the boron-amine complex monomer; the organophosphorus ligand is fed at 20-60% of the molar amount of the boron-amine complex monomer.

8. The method for preparing the boron-amine conjugated polymer with strong charge separation as described in claim 4, characterized in that, The heating reaction is carried out at a temperature of 80~100℃ for a time of 36~60h.

9. The method for preparing the boron-amine conjugated polymer with strong charge separation as described in claim 4, characterized in that, The halogenated hydrocarbon solvent is a dehydrated and deoxygenated solvent.

10. The application of the boron-amine conjugated polymer with strong charge separation as described in claim 3 in photocatalytic hydrogen production.

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