CN111892696A - A kind of dithienobenzene fused ring quinoxaline conjugated polymer and its preparation method and application - Google Patents

Abstract

The invention discloses a dithienobenzene fused ring quinoxaline conjugated polymer and a preparation method and application thereof. The invention firstly synthesizes

And then carrying out copolymerization reaction with a bi (trimethyltin) substituted heterocyclic compound to obtain the dithienobenzene fused ring quinoxaline conjugated polymer. The dithienobenzene condensed ring quinoxaline conjugated polymer has wide band gap and higher field-induced hole mobility, and can realize better absorption complementation and higher photoelectric conversion efficiency when being used in a non-fullerene thick film photoelectric functional device.

Description

A kind of dithienobenzene fused ring quinoxaline conjugated polymer and its preparation method and application

technical field

The invention relates to a dithienoacene fused-ring quinoxaline conjugated polymer and a preparation method and application thereof, belonging to the technical field of optoelectronic materials.

Background technique

The development of new green energy technology is one of the important ways to solve the problems of energy shortage and environmental pollution, and solar energy has the advantages of green, renewable, wide distribution, easy access, etc., and has broad application prospects. Therefore, the development of solar power generation technology is of great significance, and the development of solar cells is the most critical, which cannot be separated from the development of new materials.

Polymer organic solar cells are a new type of thin-film photovoltaic cells, which have the advantages of all-solid-state, wide adjustable range of photovoltaic material properties, translucency, flexible battery devices, and large-area, low-cost fabrication. Outdoor windows, car windshields, foldable curtains and other places. In polymer organic solar cells, the active material is a key factor in determining the cell efficiency. At present, the main acceptor of the active layer is generally a narrow-bandgap non-fullerene material, and the donor material is generally a conjugated polymer, while the traditional donor material is generally more narrow-bandgap conjugated polymer, and wide-bandgap conjugated polymer. There are few polymers, and the absorption complementation is not well formed to improve the utilization of the solar spectrum.

Therefore, it is urgent to develop a conjugated polymer with wide band gap, good planarity, high field-induced hole mobility, and high photoelectric conversion efficiency.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a dithienobenzene fused-ring quinoxaline conjugated polymer and its preparation method and application.

The technical scheme adopted by the present invention is:

式中，R₁为C₈～C₂₈的烷基，R₂为C₈～C₂₈的烷基，X为-H或-F，Y为-H或-F，M为

氟取代

氟取代

氟取代

中的一种，n为10～70的整数。A dithienobenzene fused ring quinoxaline conjugated polymer, the structural formula is:

In the formula, R ₁ is a C ₈ -C ₂₈ alkyl group, R ₂ is a C ₈ -C ₂₈ alkyl group, X is -H or -F, Y is -H or -F, and M is

Fluorine substitution

Fluorine substitution

Fluorine substitution

In one of them, n is an integer of 10-70.

Preferably, the R ₁ is a branched chain alkyl group of C ₈ to C ₂₈ .

Preferably, the R ₂ is a branched chain alkyl group of C ₈ to C ₂₈ .

Preferably, R ₁ and R ₂ in the dithienobenzene fused-ring quinoxaline conjugated polymer take the same group.

Preferably, the n is an integer of 30-55.

Preferably, the number-average molecular weight of the dithienobenzene-fused-ring-quinoxaline conjugated polymer is 19400-49000 g/mol.

Further preferably, the number-average molecular weight of the dithienobenzene-fused-ring-quinoxaline conjugated polymer is 21000-38500 g/mol.

Preferably, the hole mobility of the dithienobenzene-fused-ring-quinoxaline conjugated polymer is 0.01-0.10 cm ² /(V·s).

Further preferably, the hole mobility of the dithienobenzene-fused-ring-quinoxaline conjugated polymer is 0.06-0.09 cm ² /(V·s).

The preparation method of the above-mentioned dithienobenzene fused-ring quinoxaline conjugated polymer comprises the following steps:

1) converting 2-alkylthiophene into 2-alkyl-5-bromothiophene;

2) converting 2-alkyl-5-bromothiophene into 2-alkyl-4-bromothiophene;

3) Convert 2-alkyl-4-bromothiophene into

转化成

4) will

Converted to

转化成

5) will

Converted to

和双(三甲基锡)取代的杂环化合物Me₃Sn-M-SnMe₃共聚合，得到二噻吩并苯稠环喹喔啉共轭聚合物。6) will

It is copolymerized with a bis(trimethyltin) substituted heterocyclic compound Me ₃ Sn-M-SnMe ₃ to obtain a dithienobenzene fused ring quinoxaline conjugated polymer.

Preferably, the preparation method of the above-mentioned dithienobenzene fused-ring quinoxaline conjugated polymer comprises the following steps:

1) carrying out the reaction of 2-alkylthiophene and N-bromosuccinimide to obtain 2-alkyl-5-bromothiophene;

2) carry out the reaction of 2-alkyl-5-bromothiophene and lithium diisopropylamide to obtain 2-alkyl-4-bromothiophene;

3) carrying out the reaction of 2-alkyl-4-bromothiophene and 1,4-dimethylpiperazine-2,3-dione to obtain

的成环反应，得到

4) Carry out

The cyclization reaction of , yields

和

的反应，得到

5) Carry out

and

response, get

6) Carry out Copolymerization reaction with bis(trimethyltin) substituted heterocyclic compound Me ₃ Sn-M-SnMe ₃ to obtain dithienobenzene fused ring quinoxaline conjugated polymer.

A solar cell, comprising an anode, a hole transport layer, an active material layer, an electron transport layer and a cathode stacked in sequence; the active material layer includes an electron donor and an electron acceptor, and the electron donor is the above-mentioned dithieno Benzene-fused-ring quinoxaline conjugated polymer.

Preferably, the electron acceptor is a non-fullerene acceptor material.

A transistor, comprising the above-mentioned dithienobenzene fused-ring quinoxaline conjugated polymer.

The beneficial effects of the present invention are: the dithienoacene fused-ring quinoxaline conjugated polymer of the present invention has a wide band gap and high field-induced hole mobility, and can be used in non-fullerene thick-film optoelectronic functional devices. Achieve better absorption complementation and higher photoelectric conversion efficiency.

Description of drawings

Fig. 1 is the synthetic route diagram of the dithienoacene fused-ring quinoxaline conjugated polymer of the present invention.

FIG. 2 is a hydrogen nuclear magnetic resonance spectrum of 2-(2-ethylhexyl)-5-bromothiophene in Example 1. FIG.

FIG. 3 is a hydrogen nuclear magnetic resonance spectrum of 2-(2-ethylhexyl)-4-bromothiophene in Example 1. FIG.

4 is a hydrogen nuclear magnetic resonance spectrum of bis[2-(2-ethylhexyl)thiophen-4-yl]ethane-1,2-dione in Example 1. FIG.

FIG. 5 is a hydrogen nuclear magnetic resonance spectrum of 2,7-bis(2-ethylhexyl)benzodithiophene-4,5-dione in Example 1. FIG.

6 is a hydrogen nuclear magnetic resonance spectrum of 8,11-dibromo-9,10-difluoro-2,5-bis(2-ethylhexyl)dithienophenolazine in Example 1. FIG.

Detailed ways

The synthetic route of the dithienobenzene fused-ring quinoxaline conjugated polymer of the present invention is shown in FIG. 1 .

The present invention will be further explained and illustrated below in conjunction with specific embodiments.

Example 1:

A dithienobenzene fused-ring quinoxaline conjugated polymer, the preparation method comprising the following steps:

1) Preparation of 2-(2-ethylhexyl)-5-bromothiophene: add 30 mmol of 2-(2-ethylhexyl) thiophene to 35 mL of anhydrous tetrahydrofuran (THF), stir to dissolve, and then add 30 mmol of N-bromosuccinimide (NBS), stir the reaction for 3h, then add saturated sodium sulfite solution to stop the reaction, extract with n-hexane, dry the organic phase with anhydrous magnesium sulfate, remove the solvent, and separate and purify with a silica gel column to obtain 28mmol 2-(2-ethylhexyl)-5-bromothiophene (yellow liquid, yield 93.3%, 1H NMR spectrum shown in Figure 2), the reaction formula is:

2) Preparation of 2-(2-ethylhexyl)-4-bromothiophene: 26 mmol of 2-(2-ethylhexyl)-5-bromothiophene was added dropwise to 30 mmol of lithium diisopropylamide (LDA). ), react for 12h, then add distilled water to quench the reaction, extract with dichloromethane, dry the organic phase with anhydrous magnesium sulfate, remove the solvent, and separate and purify with a silica gel column to obtain 23.3mmol of 2-(2-ethylhexyl). )-4-bromothiophene (light yellow liquid, yield 89.6%, 1H NMR spectrum is shown in Figure 3), the reaction formula is:

3) Preparation of bis[2-(2-ethylhexyl)thiophen-4-yl]ethane-1,2-dione: 20 mmol of 2-(2-ethylhexyl)-4-bromothiophene was added dropwise It was added dropwise to 20 mmol of n-butyllithium (BuLi), reacted for 2 h after the addition, and then 10 mmol of 1,4-dimethylpiperazine-2,3-dione was added, and distilled water was added to quench the reaction. Extraction with methyl chloride, drying the organic phase with anhydrous magnesium sulfate, removing the solvent, and separating and purifying with a silica gel column to obtain 7.6 mmol of bis[2-(2-ethylhexyl)thiophen-4-yl]ethane-1,2 -diketone (light yellow liquid, yield 76.0%, 1H NMR spectrum is shown in Figure 4), the reaction formula is:

4) Preparation of 2,7-bis(2-ethylhexyl)benzodithiophene-4,5-dione: under nitrogen protection, 6 mmol of bis[2-(2-ethylhexyl)thiophene-4 -yl]ethane-1,2-dione was added to 20 mL of dichloromethane, stirred and dispersed, then 7.2 mmol of ferric chloride was added, the reaction was carried out for 5 h, and distilled water was added to quench the reaction, extracted with dichloromethane, and The organic phase was dried over anhydrous magnesium sulfate, the solvent was removed, and the silica gel column was used for separation and purification to obtain 4.5 mmol of 2,7-bis(2-ethylhexyl)benzodithiophene-4,5-dione (yellow-brown liquid, The yield is 75.0%, the hydrogen nuclear magnetic resonance spectrum is shown in Figure 5), and the reaction formula is:

5) Preparation of 8,11-dibromo-9,10-difluoro-2,5-bis(2-ethylhexyl)dithienophenolazine: under nitrogen protection, 3.5 mmol of 2,7-bis (2-Ethylhexyl)benzodithiophene-4,5-dione and 3.5 mmol of 3,6-dibromo-4,5-difluoro-1,2-phenylenediamine were mixed and dispersed in 30 mL of acetic acid , heated to 80°C and stirred for 24h, then added distilled water to quench the reaction, extracted with dichloromethane, washed with ammonium chloride aqueous solution, dried the organic phase with anhydrous magnesium sulfate, removed the solvent, and separated and purified by silica gel column to obtain 2.86 mmol of 8,11-dibromo-9,10-difluoro-2,5-bis(2-ethylhexyl)dithienophenolazine (orange solid, yield 81.7%, 1H NMR spectrum shown in Figure 6 shown), the reaction formula is:

6) Preparation of polymer PDTQ-1: under argon protection, 0.2 mmol of 8,11-dibromo-9,10-difluoro-2,5-bis(2-ethylhexyl)dithienophenol was prepared oxazine, 0.2mmol of 2,5-bis(trimethyltin)thiophene, 6mg of tris(dibenzylideneacetone)dipalladium, 12mg of tris(o-methylphenyl)phosphorus and 8mL of anhydrous toluene were mixed, The mixed solution was first purged with argon for 15 min, then the mixed solution was heated to 110 °C for 72 h, then the reaction solution was cooled to room temperature and dropped into methanol to collect the precipitates, followed by methanol, acetone, ethyl acetate and chloroform. Soxhlet extraction, then the chloroform extract was concentrated and then precipitated in methanol again, and vacuum dried to obtain polymer PDTQ-1 (black solid), molecular weight (GPC, THF, 60°C): Mn=8500g/mol, Mw /Mn=2.5, the reaction formula is:

Example 2:

A dithienobenzene fused-ring quinoxaline conjugated polymer, the preparation method comprising the following steps:

1) Preparation of 8,11-dibromo-9-fluoro-2,5-bis(2-ethylhexyl)dithienophenolazine: under nitrogen protection, 3.5 mmol of 2,7-bis(2- Ethylhexyl)benzodithiophene-4,5-dione (refer to Example 1 for the preparation method) and 3.5 mmol of 3,6-dibromo-4-fluoro-1,2-phenylenediamine were mixed and dispersed in 30 mL of In acetic acid, heated to 80 °C and stirred for 24 h, then added distilled water to quench the reaction, extracted with dichloromethane, washed with ammonium chloride aqueous solution, dried the organic phase with anhydrous magnesium sulfate, removed the solvent, and separated and purified with a silica gel column. Obtained 2.82 mmol of 8,11-dibromo-9-fluoro-2,5-bis(2-ethylhexyl)dithienophenolazine (orange solid, 80.6% yield), MS (EI) m/z: 692(M ⁺ ), the reaction formula is:

2) Preparation of polymer PDTQ-2: under argon protection, 0.2 mmol of 8,11-dibromo-9-fluoro-2,5-bis(2-ethylhexyl)dithienophenolazine, 0.2 mmol of 2,5-bis(trimethyltin)thiophene, 6mg of tris(dibenzylideneacetone)dipalladium, 12mg of tris(o-methylphenyl)phosphorus and 8mL of anhydrous toluene were mixed, and the mixture was first mixed with argon The mixed solution was purged with gas for 15 min, and then the mixed solution was heated to 110 °C for 72 h. The reaction solution was cooled to room temperature and dropped into methanol to collect the precipitate, followed by Soxhlet extraction with methanol, acetone, ethyl acetate and chloroform. extract, and then concentrate the chloroform extract and reprecipitate it in methanol, and vacuum dry to obtain polymer PDTQ-2 (black solid), molecular weight (GPC, THF, 60°C): Mn=7800g/mol, Mw/Mn= 3.1) The reaction formula is:

Example 3:

A dithienobenzene fused-ring quinoxaline conjugated polymer, the preparation method comprising the following steps:

1) Preparation of 8,11-dibromo-2,5-bis(2-ethylhexyl)dithienophenolazine: under nitrogen protection, 3.5 mmol of 2,7-bis(2-ethylhexyl) Benzodithiophene-4,5-dione (refer to Example 1 for preparation method) and 3.5 mmol of 3,6-dibromo-1,2-phenylenediamine were mixed and dispersed in 30 mL of acetic acid, heated to 80°C and stirred The reaction was carried out for 24 h, then distilled water was added to quench the reaction, extracted with dichloromethane, washed with aqueous ammonium chloride solution, dried with anhydrous magnesium sulfate, the organic phase was dried, the solvent was removed, and the silica gel column was used for separation and purification to obtain 2.9 mmol of 8,11- Dibromo-2,5-bis(2-ethylhexyl)dithienophenolazine (orange solid, yield 82.9%), MS (EI) m/z: 674 (M ⁺ ), the reaction formula is:

2) Preparation of polymer PDTQ-3: under argon protection, 0.2 mmol of 8,11-dibromo-2,5-bis(2-ethylhexyl)dithienophenolazine, 0.2 mmol of 2, 5-Bis(trimethyltin)thiophene, 6mg of tris(dibenzylideneacetone)dipalladium, 12mg of tris(o-methylphenyl)phosphorus and 8mL of anhydrous toluene were mixed, first purged with argon and mixed The solution was heated to 110 °C for 15 min, and the reaction was carried out for 72 h. The reaction solution was cooled to room temperature and dropped into methanol. The precipitate was collected, followed by Soxhlet extraction with methanol, acetone, ethyl acetate and chloroform. The chloroform extract was concentrated and then reprecipitated in methanol and dried in vacuo to obtain polymer PDTQ-3 (black solid), molecular weight (GPC, THF, 60°C): Mn=8700g/mol, Mw/Mn=2.8, reaction formula for:

Example 4:

A dithienobenzene fused-ring quinoxaline conjugated polymer, the preparation method comprising the following steps:

1) Preparation of 2-(2-hexyldecyl)-5-bromothiophene: add 30 mmol of 2-(2-hexyldecyl) thiophene to 35 mL of anhydrous tetrahydrofuran (THF), stir to dissolve, and then add 30 mmol of N-bromosuccinimide (NBS), stir the reaction for 3h, then add saturated sodium sulfite solution to stop the reaction, extract with n-hexane, dry the organic phase with anhydrous magnesium sulfate, remove the solvent, and separate and purify with a silica gel column to obtain 27.1 mmol of 2-(2-hexyldecyl)-5-bromothiophene (yellow liquid, yield 90.2%), the reaction formula is:

2) Preparation of 2-(2-hexyldecyl)-4-bromothiophene: 26 mmol of 2-(2-hexyldecyl)-5-bromothiophene was added dropwise to 30 mmol of lithium diisopropylamide (LDA). ), react for 12h, then add distilled water to quench the reaction, extract with dichloromethane, dry the organic phase with anhydrous magnesium sulfate, remove the solvent, and separate and purify with a silica gel column to obtain 22.7mmol of 2-(2-hexyldecyl). )-4-bromothiophene (pale yellow liquid, yield 87.2%), the reaction formula is:

3) Preparation of bis[2-(2-hexyldecyl)thiophen-4-yl]ethane-1,2-dione: 20 mmol of 2-(2-hexyldecyl)-4-bromothiophene was added dropwise It was added dropwise to 20 mmol of n-butyllithium (BuLi), reacted for 2 h after the addition, and then 10 mmol of 1,4-dimethylpiperazine-2,3-dione was added, and distilled water was added to quench the reaction. Extraction with methyl chloride, drying the organic phase with anhydrous magnesium sulfate, removing the solvent, and separating and purifying with a silica gel column to obtain 15.1 mmol of bis[2-(2-hexyldecyl)thiophen-4-yl]ethane-1,2 -diketone (pale yellow liquid, yield 75.3%), the reaction formula is:

4) Preparation of 2,7-bis(2-hexyldecyl)benzodithiophene-4,5-dione: under nitrogen protection, 6 mmol of bis[2-(2-hexyldecyl)thiophene-4 -yl]ethane-1,2-dione was added to 20 mL of dichloromethane, stirred and dispersed, then 7.2 mmol of ferric chloride was added, the reaction was carried out for 5 h, and distilled water was added to quench the reaction, extracted with dichloromethane, and The organic phase was dried over anhydrous magnesium sulfate, the solvent was removed, and the silica gel column was used for separation and purification to obtain 4.4 mmol of 2,7-bis(2-hexyldecyl)benzodithiophene-4,5-dione (yellow-brown liquid, Yield 73.3%), the reaction formula is:

5) Preparation of 8,11-dibromo-2,5-bis(2-hexyldecyl)dithienophenolazine: under nitrogen protection, 3.5 mmol of 2,7-bis(2-hexyldecyl) Benzodithiophene-4,5-dione and 3.5mmol of 3,6-dibromo-1,2-phenylenediamine were mixed and dispersed in 30mL of acetic acid, heated to 80°C and stirred for 24h, and then added distilled water to quench The reaction was extracted with dichloromethane, washed with aqueous ammonium chloride solution, dried with anhydrous magnesium sulfate, the organic phase was removed, the solvent was removed, and 2.85 mmol of 8,11-dibromo-2,5-bis- (2-hexyldecyl)dithienophenolazine (orange solid, yield 81.4%), MS (EI) m/z: 898 (M ⁺ ), the reaction formula is:

6) Preparation of polymer PDTQ-4: under argon protection, 0.2 mmol of 8,11-dibromo-2,5-bis(2-hexyldecyl)dithienophenolazine, 0.2 mmol of 2,5-bis(2-hexyldecyl)dithienophenolazine, 5-Bis(trimethyltin)thiophene, 6mg of tris(dibenzylideneacetone)dipalladium, 12mg of tris(o-methylphenyl)phosphorus and 8mL of anhydrous toluene were mixed, first purged with argon and mixed The solution was heated to 110 °C for 15 min, and the reaction was carried out for 72 h. The reaction solution was cooled to room temperature and dropped into methanol. The precipitate was collected, followed by Soxhlet extraction with methanol, acetone, ethyl acetate and chloroform. The chloroform extract was concentrated and then precipitated in methanol again, and dried in vacuum to obtain polymer PDTQ-4 (black solid), molecular weight (GPC, THF, 60°C): Mn=11200g/mol, Mw/Mn=2.2, reaction formula for:

Example 5:

A dithienobenzene fused-ring quinoxaline conjugated polymer, the preparation method comprising the following steps:

1) Preparation of 8,11-dibromo-9-fluoro-2,5-bis(2-hexyldecyl)dithienophenolazine: under nitrogen protection, 3.5 mmol of 2,7-bis(2- Hexyldecyl)benzodithiophene-4,5-dione (refer to Example 4 for preparation method) and 3.5 mmol of 3,6-dibromo-4-fluoro-1,2-phenylenediamine were mixed and dispersed in 30 mL of In acetic acid, heated to 80 °C and stirred for 24 h, then added distilled water to quench the reaction, extracted with dichloromethane, washed with ammonium chloride aqueous solution, dried the organic phase with anhydrous magnesium sulfate, removed the solvent, and separated and purified with a silica gel column. Obtained 2.83 mmol of 8,11-dibromo-9-fluoro-2,5-bis(2-hexyldecyl)dithienophenolazine (orange solid, 80.8% yield), MS (EI) m/z: 916(M ⁺ ), the reaction formula is:

2) Preparation of polymer PDTQ-5: under argon protection, 0.2 mmol of 8,11-dibromo-9-fluoro-2,5-bis(2-hexyldecyl)dithienophenolazine, 0.2 mmol of 5,5'-bistrimethyltin-2,2'-bithiophene, 6 mg of tris(dibenzylideneacetone)dipalladium, 12 mg of tris(o-methylphenyl)phosphorus and 8 mL of anhydrous Toluene was mixed, the mixed solution was first purged with argon for 15 min, then the mixed solution was heated to 110 °C for 72 h, the reaction solution was cooled to room temperature and dropped into methanol to collect the precipitate, followed by methanol, acetone and ethyl acetate. Soxhlet extraction was carried out with chloroform, and the chloroform extract was concentrated and precipitated in methanol again, and vacuum-dried to obtain polymer PDTQ-5 (black solid), molecular weight (GPC, THF, 60°C): Mn=9800g/ mol, Mw/Mn=2.7, the reaction formula is:

Example 6:

A dithienobenzene fused-ring quinoxaline conjugated polymer, the preparation method comprising the following steps:

1) Preparation of 8,11-dibromo-9,10-difluoro-2,5-bis(2-hexyldecyl)dithienophenolazine: under nitrogen protection, 3.5 mmol of 2,7-bis (2-hexyldecyl)benzodithiophene-4,5-dione (refer to Example 4 for the preparation method) and 3.5 mmol of 3,6-dibromo-4,5-difluoro-1,2-benzenedione The amine was mixed and dispersed in 30 mL of acetic acid, heated to 80 °C and stirred for 24 h, then added distilled water to quench the reaction, extracted with dichloromethane, washed with aqueous ammonium chloride solution, dried with anhydrous magnesium sulfate, and the organic phase was removed. Silica gel column separation and purification to obtain 2.86mmol of 8,11-dibromo-9,10-difluoro-2,5-bis(2-hexyldecyl)dithienophenolazine (orange solid, yield 81.8%) , MS(EI) m/z: 934(M ⁺ ), the reaction formula is:

2) Preparation of polymer PDTQ-6: under argon protection, 0.2 mmol of 8,11-dibromo-9,10-difluoro-2,5-bis(2-hexyldecyl)dithienophenol was prepared oxazine, 0.2 mmol of 2,5-bis(trimethyltin)-thieno[3,2-b]thiophene, 6 mg of tris(dibenzylideneacetone)dipalladium, 12 mg of tris(o-methylphenyl) ) Phosphorus was mixed with 8 mL of anhydrous toluene, the mixed solution was first purged with argon for 15 min, then the mixed solution was heated to 110 °C for 72 h, the reaction solution was cooled to room temperature and dropped into methanol, the precipitate was collected, followed by Soxhlet extraction was carried out with methanol, acetone, ethyl acetate and chloroform, and then the chloroform extract was concentrated and then reprecipitated in methanol, and dried in vacuo to obtain polymer PDTQ-6 (black solid), molecular weight (GPC, THF, 60 ℃): Mn=9900g/mol, Mw/Mn=2.9, the reaction formula is:

Example 7:

A dithienobenzene fused-ring quinoxaline conjugated polymer, the preparation method comprising the following steps:

1) Preparation of 2-(2-dodecylhexadecyl)-5-bromothiophene: 30 mmol of 2-(2-dodecylhexadecyl)thiophene was added to 35 mL of In water tetrahydrofuran (THF), stir to dissolve, then add 30mmol of N-bromosuccinimide (NBS), stir for 3h, then add saturated sodium sulfite solution to stop the reaction, extract with n-hexane, and dry the organic matter with anhydrous magnesium sulfate. phase, remove the solvent, and separate and purify with a silica gel column to obtain 26.9 mmol of 2-(2-dodecylhexadecyl)-5-bromothiophene (yellow liquid, yield 89.7%). The reaction formula is: :

2) Preparation of 2-(2-dodecylhexadecyl)-4-bromothiophene: 26 mmol of 2-(2-dodecylhexadecyl)-5-bromothiophene Add dropwise 30mmol of lithium diisopropylamide (LDA), react for 12h, then add distilled water to quench the reaction, extract with dichloromethane, dry the organic phase with anhydrous magnesium sulfate, remove the solvent, and separate with a silica gel column Purification to obtain 22.2mmol of 2-(2-dodecylhexadecyl)-4-bromothiophene (light yellow liquid, yield 85.3%), the reaction formula is:

3) Preparation of bis[2-(2-dodecylhexadecyl)thiophen-4-yl]ethane-1,2-dione: 20 mmol of 2-(2-dodecane (base hexadecyl)-4-bromothiophene was added dropwise to 20mmol of n-butyllithium (BuLi), reacted for 2h after the addition, and then added 10mmol of 1,4-dimethylpiperazine-2, 3-diketone, then added distilled water to quench the reaction, extracted with dichloromethane, dried the organic phase with anhydrous magnesium sulfate, removed the solvent, and separated and purified by silica gel column to obtain 14.6mmol of bis[2-(2-dodecane]. Carboalkylhexadecyl)thiophen-4-yl]ethane-1,2-dione (pale yellow liquid, yield 72.9%), the reaction formula is:

4) Preparation of 2,7-bis(2-dodecylhexadecyl)benzodithiophene-4,5-dione: under nitrogen protection, 6 mmol of bis[2-(2- Dodecylhexadecyl)thiophen-4-yl]ethane-1,2-dione was added to 20mL of dichloromethane, stirred and dispersed, then 7.2mmol of ferric chloride was added, and the reaction was carried out for 5h. Then add distilled water to quench the reaction, extract with dichloromethane, dry the organic phase with anhydrous magnesium sulfate, remove the solvent, and separate and purify with a silica gel column to obtain 4.3 mmol of 2,7-bis(2-dodecyl tenacyl) Hexacarbonyl)benzodithiophene-4,5-dione (yellow-brown liquid, yield 71.4%), the reaction formula is:

5) Preparation of 8,11-dibromo-2,5-bis(2-dodecylhexadecyl)dithienophenolazine: under nitrogen protection, 3.5 mmol of 2,7-bis (2-Dodecylhexadecyl)benzodithiophene-4,5-dione and 3.5mmol of 3,6-dibromo-1,2-phenylenediamine were mixed and dispersed in 30mL of acetic acid , heated to 80°C and stirred for 24h, then added distilled water to quench the reaction, extracted with dichloromethane, washed with ammonium chloride aqueous solution, dried the organic phase with anhydrous magnesium sulfate, removed the solvent, and separated and purified with silica gel column to obtain 2.81 mmol of 8,11-dibromo-2,5-bis(2-dodecylhexadecyl)dithienophenolazine (orange solid, 80.2% yield), MS (EI) m/z : 1234(M ⁺ ), the reaction formula is:

6) Preparation of polymer PDTQ-7: under argon protection, 0.2 mmol of 8,11-dibromo-2,5-bis(2-dodecylhexadecyl)dithienophenol was prepared oxazine, 0.2 mmol of 2,5-bis(trimethyltin)-thieno[3,2-b]thiophene, 6 mg of tris(dibenzylideneacetone)dipalladium, 12 mg of tris(o-methylphenyl) ) Phosphorus was mixed with 8 mL of anhydrous toluene, the mixed solution was first purged with argon for 15 min, then the mixed solution was heated to 110 °C for 72 h, the reaction solution was cooled to room temperature and dropped into methanol, the precipitate was collected, followed by Soxhlet extraction was carried out with methanol, acetone, ethyl acetate and chloroform, and the chloroform extract was concentrated and then reprecipitated in methanol, and dried in vacuo to obtain polymer PDTQ-7 (black solid), molecular weight (GPC, THF, 60 ℃): Mn=7900g/mol, Mw/Mn=3.2, the reaction formula is:

Example 8:

A dithienobenzene fused-ring quinoxaline conjugated polymer, the preparation method comprising the following steps:

1) Preparation of 8,11-dibromo-9-fluoro-2,5-bis(2-dodecylhexadecyl)dithienophenolazine: under nitrogen protection, 3.5 mmol of 2 , 7-bis(2-dodecylhexadecyl)benzodithiophene-4,5-dione (refer to Example 7 for the preparation method) and 3.5 mmol of 3,6-dibromo-4-dione Fluoro-1,2-phenylenediamine was mixed and dispersed in 30 mL of acetic acid, heated to 80 °C and stirred for 24 h, then distilled water was added to quench the reaction, extracted with dichloromethane, washed with aqueous ammonium chloride, and washed with anhydrous magnesium sulfate. The organic phase was dried, the solvent was removed, and the silica gel column was used for separation and purification to obtain 2.89mmol of 8,11-dibromo-9-fluoro-2,5-bis(2-dodecylhexadecyl)dithiophene Paprolazine (orange solid, yield 82.6%), MS (EI) m/z: 1252 (M ⁺ ), the reaction formula is:

2) Preparation of polymer PDTQ-8: under argon protection, 0.2 mmol of 8,11-dibromo-9-fluoro-2,5-bis(2-dodecylhexadecyl) Dithienophenolazine, 0.2 mmol of 2,5-bis(trimethyltin)-3,6-difluoro-thieno[3,2-b]thiophene, 6 mg of tris(dibenzylideneacetone)di Palladium, 12 mg of tris(o-methylphenyl) phosphorus and 8 mL of anhydrous toluene were mixed, the mixed solution was first purged with argon for 15 min, then the mixed solution was heated to 110°C for 72 h, and then the reaction solution was cooled to room temperature And drop into methanol, collect the precipitation, carry out Soxhlet extraction with methanol, acetone, ethyl acetate and chloroform successively, again after the chloroform extract is concentrated, reprecipitate in methanol, and vacuum-dry to obtain polymer PDTQ-8 ( Black solid), molecular weight (GPC, THF, 60°C): Mn=7600g/mol, Mw/Mn=3.3, the reaction formula is:

Example 9:

A dithienobenzene fused-ring quinoxaline conjugated polymer, the preparation method comprising the following steps:

1) Preparation of 8,11-dibromo-9,10-difluoro-2,5-bis(2-dodecylhexadecyl)dithienophenolazine: under nitrogen protection, 3.5 mmol of 2,7-bis(2-dodecylhexadecyl)benzodithiophene-4,5-dione (refer to Example 7 for the preparation method) and 3.5mmol of 3,6-dibromo -4,5-Difluoro-1,2-phenylenediamine was mixed and dispersed in 30 mL of acetic acid, heated to 80 °C and stirred for 24 h, then distilled water was added to quench the reaction, extracted with dichloromethane, and washed with ammonium chloride aqueous solution , the organic phase was dried with anhydrous magnesium sulfate, the solvent was removed, and the silica gel column was used for separation and purification to obtain 2.8mmol of 8,11-dibromo-9,10-difluoro-2,5-bis(2-dodecane) hexadecyl)dithienophenolazine (orange solid, yield 80.0%), MS (EI) m/z: 1270 (M ⁺ ), the reaction formula is:

2) Preparation of polymer PDTQ-9: under argon protection, 0.2 mmol of 8,11-dibromo-9,10-difluoro-2,5-bis(2-dodecylhexadecyl) Alkyl)dithienophenolazine, 0.2 mmol of 3,3'-difluoro-5,5'-bistrimethyltin-2,2'-bithiophene, 6 mg of tris(dibenzylideneacetone)di Palladium, 12 mg of tris(o-methylphenyl) phosphorus and 8 mL of anhydrous toluene were mixed, the mixed solution was first purged with argon for 15 min, then the mixed solution was heated to 110°C for 72 h, and then the reaction solution was cooled to room temperature And drop into methanol, collect the precipitation, carry out Soxhlet extraction with methanol, acetone, ethyl acetate and chloroform successively, and then concentrate the chloroform extract and reprecipitate in methanol, and vacuum dry to obtain polymer PDTQ-9 ( Black solid), molecular weight (GPC, THF, 60°C): Mn=8300g/mol, Mw/Mn=3.5, the reaction formula is:

Performance Testing:

1) Preparation and performance of solar cells:

The fabrication process of the solar cell: take pre-cleaned ITO glass as the cathode, spin-coat a layer of PEDOT:PSS with a thickness of 40nm on the ITO glass as the cathode buffer layer, and then spin-coat a 130nm photovoltaic active layer (dithiophene) on the ITO glass after vacuum drying. Acene-fused-ring-quinoxaline conjugated polymer: acceptor material ITIC=1:1, mass ratio), dried at 70 °C for 10 min, and continued to spin-coat a layer of 10 nm thick PFN (conjugated polymer [9,9- Dioctylfluorene-9,9-bis(N,N-dimethylaminopropyl)fluorene]) was used as the anode modification layer, a 100nm Al metal anode was vacuum evaporated, and a negative bias was applied between the ITO and Al metal electrodes , and its battery characteristics were measured under the illumination of 100mW/cm ² AM1.5 simulated sunlight.

Test Results:

The open-circuit voltage of the solar cell containing polymer PDTQ-1 is 0.89V, the short-circuit current is 17.23mA/cm ² , the fill factor is 67.5%, and the energy conversion efficiency is 10.35%;

The open-circuit voltage of the solar cell containing polymer PDTQ-2 is 0.87V, the short-circuit current is 13.21mA/cm ² , the fill factor is 58.23%, and the energy conversion efficiency is 6.69%;

The open-circuit voltage of the solar cell containing polymer PDTQ-3 is 0.80V, the short-circuit current is 8.72mA/cm ² , the fill factor is 51.45%, and the energy conversion efficiency is 3.59%;

The open-circuit voltage of the solar cell containing polymer PDTQ-4 is 0.82V, the short-circuit current is 9.35mA/cm ² , the fill factor is 50.62%, and the energy conversion efficiency is 3.88%;

The open-circuit voltage of the solar cell containing polymer PDTQ-5 is 0.85V, the short-circuit current is 15.86mA/cm ² , the fill factor is 54.33%, and the energy conversion efficiency is 7.32%;

The open-circuit voltage of the solar cell containing polymer PDTQ-6 is 0.86V, the short-circuit current is 17.23mA/cm ² , the fill factor is 63.75%, and the energy conversion efficiency is 9.44%;

The open-circuit voltage of the solar cell containing polymer PDTQ-7 is 0.81V, the short-circuit current is 7.95mA/cm ² , the fill factor is 59.73%, and the energy conversion efficiency is 3.85%;

The open-circuit voltage of the solar cell containing polymer PDTQ-8 is 0.91V, the short-circuit current is 6.78mA/cm ² , the fill factor is 52.13%, and the energy conversion efficiency is 3.22%;

The open-circuit voltage of the solar cell containing polymer PDTQ-9 was 0.92 V, the short-circuit current was 9.77 mA/cm ² , the fill factor was 51.83%, and the energy conversion efficiency was 4.66%.

2) Preparation and performance of transistors:

The fabrication process of the transistor: using the upper contact geometry, using silver as the source and drain electrodes, using highly doped n-type silicon and thermally grown silicon dioxide as the substrate and gate insulating layer, respectively, n-octyl three Chlorosilane was used as the surface modifier of the gate electrode, and then at 2500 rmp, a 11 mg/mL solution of dithienobenzene-fused-ring-quinoxaline conjugated polymer in xylene was spun into a 50-nm-thick polymer film on a spinner. , and then dried at 110 °C for 10 min. A layer of 50 nm thick silver film was vacuum evaporated as the source and drain electrodes. The ratio of the width to the length of the transistor was 100:1, and then characterized by a probe workstation and an Agilent 4155C semiconductor analyzer.

Test Results:

The field-induced mobilities of organic field effect transistors containing polymers PDTQ-1 to PDTQ-9 are 0.07cm ² /(V·s), 0.09cm ² /(V·s), and 0.10cm ² /(V·s, respectively ), 0.06cm ² /(V·s), 0.08cm ² /(V·s), 0.10cm ² /(V·s), 0.05cm ^{2 /(V·s), 0.02cm 2 /} (V·s ) and 0.01 cm ² /(V·s).

The above-mentioned embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited by the above-mentioned embodiments, and any other changes, modifications, substitutions, combinations, The simplification should be equivalent replacement manners, which are all included in the protection scope of the present invention.

Claims (10)

1. a dithienobenzene condensed ring quinoxaline conjugated polymer is characterized in that: structural formula is:

In the formula, R ₁ is a C ₈ -C ₂₈ alkyl group, R ₂ is a C ₈ -C ₂₈ alkyl group, X is -H or -F, Y is -H or -F, and M is

Fluorine substitution

Fluorine substitution

Fluorine substitution

In one of them, n is an integer of 10-70. 2 . The dithienobenzene fused-ring quinoxaline conjugated polymer according to claim 1 , wherein the R ₁ is a branched chain alkyl group of C ₈ to C ₂₈ . 3 . 3 . The dithienobenzene fused-ring quinoxaline conjugated polymer according to claim 2 , wherein the R ₂ is a branched chain alkyl group of C ₈ to C ₂₈ . 4 . 4. The dithienoacene fused-ring quinoxaline conjugated polymer according to any one of claims 1 to 3, wherein the number of the dithienoacene fused-ring quinoxaline conjugated polymer The average molecular weight is 19400～49000g/mol. 5. The dithienoacene fused-ring quinoxaline conjugated polymer according to any one of claims 1 to 3, characterized in that: the hollow of the dithienoacene fused-ring quinoxaline conjugated polymer The hole mobility was 0.01 to 0.10 cm ² /(V·s). 6. The preparation method of the dithienobenzene fused-ring quinoxaline conjugated polymer according to any one of claims 1 to 5, characterized in that: comprising the following steps: 1) converting 2-alkylthiophene into 2-alkyl-5-bromothiophene; 2) converting 2-alkyl-5-bromothiophene into 2-alkyl-4-bromothiophene; 3) Convert 2-alkyl-4-bromothiophene into

4) will

Converted to

5) will

Converted to

6) will

It is copolymerized with a bis(trimethyltin) substituted heterocyclic compound Me ₃ Sn-M-SnMe ₃ to obtain a dithienobenzene fused ring quinoxaline conjugated polymer. 7. preparation method according to claim 6 is characterized in that: comprise the following steps: 1) carrying out the reaction of 2-alkylthiophene and N-bromosuccinimide to obtain 2-alkyl-5-bromothiophene; 2) carry out the reaction of 2-alkyl-5-bromothiophene and lithium diisopropylamide to obtain 2-alkyl-4-bromothiophene; 3) carrying out the reaction of 2-alkyl-4-bromothiophene and 1,4-dimethylpiperazine-2,3-dione to obtain

4) Carry out

The cyclization reaction of , yields

5) Carry out

response, get

6) Carry out

Copolymerization reaction with bis(trimethyltin) substituted heterocyclic compound Me ₃ Sn-M-SnMe ₃ to obtain dithienobenzene fused ring quinoxaline conjugated polymer. 8. A solar cell, characterized in that it comprises an anode, a hole transport layer, an active material layer, an electron transport layer and a cathode which are stacked in sequence; the active material layer comprises an electron donor and an electron acceptor, and the electron donor The body is the dithienobenzene fused-ring quinoxaline conjugated polymer according to any one of claims 1 to 5. 9 . The solar cell of claim 8 , wherein the electron acceptor is a non-fullerene acceptor material. 10 . 10 . A transistor, characterized by comprising the dithienoacene fused-ring quinoxaline conjugated polymer according to any one of claims 1 to 5 . 11 .

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