阅读说明：本技术 一种非富勒烯电子受体的制备方法和产品及应用 (Preparation method of non-fullerene electron acceptor, product and application ) 是由 赖文勇 张超 李祥春 汪洋 刘芳 于 2021-06-17 设计创作，主要内容包括：本发明公开了一种非富勒烯电子受体的制备方法和产品及应用,该材料采用芳族或杂芳族稠环扩大平面π共轭骨架作为臂单元,促进了π电子离域和分子堆积,作为平面骨架的一部分,稠环结构可以促进红移吸收、降低电离能和增加结晶度等,将π延伸的共轭结构和富含噻吩结构的稠环核引入到星形结构中,不仅使之保持了线性结构的吸收强、易于修饰、热稳定性好、给电子能力强和刚性好等优点,还显示出延伸的吸收、降低的带隙和增加的迁移率,从而显著地提高有机太阳能电池器件性能。(The invention discloses a preparation method of a non-fullerene electron acceptor, a product and an application thereof, the material adopts an aromatic or heteroaromatic condensed ring enlarged plane pi conjugated skeleton as an arm unit to promote pi electron delocalization and molecular accumulation, the condensed ring structure can promote red shift absorption, reduce ionization energy, increase crystallinity and the like as a part of the plane skeleton, and a pi extended conjugated structure and a condensed ring nucleus rich in a thiophene structure are introduced into a star structure, so that the advantages of strong absorption of a linear structure, easy modification, good thermal stability, strong electron donating capability, good rigidity and the like are maintained, and the extended absorption, the reduced band gap and the increased mobility are displayed, thereby obviously improving the performance of an organic solar cell device.)

1. A non-fullerene electron acceptor material, characterized by: the material takes a benzotrithiophene electron donating group as a central arm unit, a condensed ring structure as an arm unit, hetero atoms are introduced into the condensed ring and modified by adopting a side group, and the end group is blocked by using a 3- (dicyanomethylene) indolone group and a derivative thereof to obtain the non-fullerene electron acceptor, which comprises a structural general formula shown as the following formula I:

wherein Ar is selected from one of the following structures II:

in formula II, R, R₁、R₂、R₃Respectively is one of C1-C30 alkyl, alkoxy, alkylphenyl, alkylphenoxy, alkyl ester group and aryl ester group; d is one or more of S, N, O, Si, Ge, B and Se heteroatoms; x is H, CH₃One or two of F, Cl, Br and I; and x is a linking site.

2. The non-fullerene electron acceptor material of claim 1, wherein: the material is any one compound in the following structures IV-XX I:

wherein, R, R₁、R₂、R₃Independently selected from one of C1-C30 alkyl, alkoxy, alkylphenyl, alkylphenoxy, alkyl ester group and aryl ester group, and has a structure shown in a formula III;

d is one or more of S, N, O, Si, Ge, B and Se heteroatoms; x is independently selected from one or two of H, CH3, F, Cl, Br and I.

3. A method of preparing a non-fullerene electron acceptor material according to claim 1 or 2, wherein: comprises the steps of (a) preparing a mixture of a plurality of raw materials,

step (1): adding the reactant (a), the reactant (b) and a strong oxidant into a closed reaction bottle, injecting a certain amount of organic solvent to dissolve the reactants, and reacting for a period of time under a certain temperature condition in an inert gas protective environment. Extracting the obtained mother liquor with an organic solvent and water, drying by a drying agent, distilling under reduced pressure to evaporate redundant solvent, purifying by a silica gel chromatographic column, and finally drying to obtain a compound (c);

step (2): the product compound (c) of step (1) was added to a reaction vessel and dissolved in an organic solvent, and placed in an ice-water mixture under stirring under dark conditions. Then (d) dissolving in an organic solvent is injected into a reaction container drop by drop, the mixture reacts for a certain time at a certain temperature under the protection of inert gas, the obtained mother liquor is extracted by the organic solvent and water, and then is dried by a drying agent, and then the redundant solvent is distilled out by reduced pressure distillation, and is purified by a silica gel chromatographic column, and finally the compound (e) is obtained;

and (3): adding the product compound (e) obtained in the step (2), the compound (f), tetrabutylammonium bromide and tetratriphenylphosphine palladium into a reaction vessel, dissolving the mixture in an organic solvent, reacting for a period of time at a certain temperature under the protection of inert gas, and extracting and purifying to obtain a compound (g);

and (4): adding the product compound (g) obtained in the step (3), the compound (h) and a catalyst into a reaction vessel, dissolving the product compound (g), the compound (h) and the catalyst into an organic solvent, reacting for a certain time at a certain temperature, and further purifying to obtain a compound (i);

comprises the following synthetic routes and synthetic steps:

4. the method of preparing a non-fullerene electron acceptor material according to claim 3, wherein: the strong oxidant in the step (1) is one of peroxide, persulfate, nitrate, permanganate, dichromate and chlorate; the organic solvent is one or more of 1, 2-dichloroethane, chloroform, tetrahydrofuran, toluene and chlorobenzene; the inert gas is one or more of nitrogen, argon and hydrogen; the reaction temperature is 70-200 ℃, and the reaction time is 1-72 h; the drying agent is one or more of anhydrous sodium sulfate, anhydrous magnesium sulfate, anhydrous barium sulfate and concentrated sulfuric acid; the molar ratio of reactant (a) to reactant (b) is 1:1 to 1.8.

5. The method of preparing a non-fullerene electron acceptor material according to claim 3, wherein: the organic solvent used in the step (2) is one or more of dichloromethane, trichloromethane, toluene, chlorobenzene, o-dichlorobenzene and tetrahydrofuran; the inert gas is one or more of nitrogen, argon and hydrogen, the reaction temperature is 70-200 ℃, and the reaction time is 1-72 hours; the drying agent is one or more of anhydrous sodium sulfate, anhydrous magnesium sulfate, anhydrous barium sulfate and concentrated sulfuric acid; the molar ratio of compound (c) to reactant (d) is 1:1 to 1.8.

6. The method of preparing a non-fullerene electron acceptor material according to claim 3, wherein: the organic solvent used in the step (3) is one or more of dichloromethane, trichloromethane, toluene, chlorobenzene, o-dichlorobenzene and tetrahydrofuran; the inert gas used is one or more of nitrogen, argon and hydrogen; the reaction temperature is 70-200 ℃, and the reaction time is 1-72 h; reactant (f): compound (e): tetrabutylammonium bromide: the molar ratio of the tetratriphenylphosphine palladium is 1: (3-6): (0.1-0.2): (0.01-0.05); in the step (4), the reaction temperature is 70-200 ℃, the reaction time is 1-72 h, the catalyst is one of pyridine, triethylamine, sodium amide and quaternary ammonium hydroxide, and the molar ratio of the compound (g) to the compound (h) is 1: 3 to 8.

7. The use of the non-fullerene electron acceptor material according to any one of claims 1 to 6 as an electron acceptor material in an organic optoelectronic device, wherein: the organic photoelectric device includes an organic solar cell device, a sensor, and electronic paper.

8. The use of claim 7, wherein: the organic photoelectric device is manufactured by adopting a solution processing method, and the solution processing method comprises spin coating, screen printing and ink-jet printing.

9. The use of claim 7, wherein: the organic solar cell device is a tandem laminated organic solar cell device; the organic solar cell device structure can adopt a positive structure or an inverted structure; the organic solar cell device structure can be used for preparing large-area organic solar cells.

Technical Field

The invention belongs to the technical field of photoelectric material application, and particularly relates to a preparation method of a non-fullerene electron acceptor, a product and application.

Background

In recent years, Organic Solar Cells (OSCs) have gained widespread attention and great progress over the past five years due to molecular structural design, particularly with respect to non-fullerene electron acceptors (NFAs). Among the various non-fullerene electron acceptors, fused ring electron acceptors have proven to be the most efficient way to achieve high conversion efficiencies. The fusion of an electron acceptor containing a capping group with a ladder electron-donating core having a linear electron acceptor-electron donor-electron acceptor (a-D-a) configuration is considered to be a typical representation of non-fullerene electron acceptors. For the preparation of fused ring nuclei, it is generally effective to enlarge a planar pi-conjugated skeleton with an aromatic or heteroaromatic fused ring to promote pi-electron delocalization and molecular stacking. In particular, thieno fused rings are important as part of a planar skeleton in terms of red-shifted spectral absorption, reduction in ionization energy, and increase in crystallinity. Guided by these design principles, a series of novel linear fused ring electron acceptors with pi extension and thiophene-rich structures were developed, showing expanded spectral absorption, reduced band gap and increased mobility, thereby significantly improving device performance.

Although most efforts have focused on linear fused ring electron acceptors, star electron acceptors are also currently of particular interest because they extend pi-conjugation in two or three dimensions through a central core unit. This structure will result in stronger light absorption and higher charge co-transport than a linear electron acceptor. When building star electron acceptors, the main concern is the balance between planar and twisted structures, which is directly related to balancing electron mobility and exciton dissociation.

Disclosure of Invention

This section is for the purpose of summarizing some aspects of embodiments of the invention and to briefly introduce some preferred embodiments. In this section, as well as in the abstract and the title of the invention of this application, simplifications or omissions may be made to avoid obscuring the purpose of the section, the abstract and the title, and such simplifications or omissions are not intended to limit the scope of the invention.

The present invention has been made keeping in mind the above and/or other problems occurring in the prior art.

Therefore, an object of the present invention is to provide a non-fullerene electron acceptor material, a method for preparing the same, and applications thereof, which can be used to prepare organic solar cell devices with an upright device structure and an inverted device structure by solution processing, such as spin coating or inkjet printing, or can be used to prepare large-area stacked organic solar cell devices in a serial manner, and achieve excellent photoelectric characteristics by changing the molecular structure of the arm unit and optimizing the device structure, thereby not only maintaining the advantages of strong spectral absorption, easy modification, good thermal stability, strong electron donating ability, good rigidity, etc. of the linear arm unit structure, but also interacting with the central benzothiophene core unit, showing extended absorption, reduced band gap, and increased mobility, and overcoming the disadvantages of forbidden optical transition caused by the highly symmetric wave function of the fullerene electron acceptor, Poor stability of the material film, limited transmission of isotropic current carriers of a linear electron acceptor and the like.

The invention has the beneficial effects that:

the invention provides a non-fullerene electron acceptor material, which takes a benzotrithiophene electron donating group as a central core unit, a condensed ring structure as an arm unit, hetero atoms introduced into the condensed ring structure of the arm unit are modified by adopting side groups, and the end groups are terminated by using 3- (dicyanomethylene) Indolone (IC) groups and derivatives thereof; the material is synthesized through a series of processes such as Wuerger-Ziegler reaction, Vilsmeier-Haake reaction, Suzuki reaction and the like, and has the advantages of mature and easy control of the synthesis process, easy separation and purification of the synthesized product, high synthesis yield and the like; the condensed ring structure of the arm unit has the advantages of strong spectrum absorption, easy modification of the structure, good thermal stability, strong electron donating capability, good rigidity and the like, the central core unit and the arm unit enhance the conjugation effect of the material, the configuration is more diversified, the material has excellent film stability, high charge mobility, excellent molar absorption coefficient and good film form, and the side chain group endows the material with excellent solubility and film forming property.

The non-fullerene electron acceptor material is suitable for processing modes such as spin coating, ink-jet printing and the like, and can perform effective spectrum complementary absorption and energy level matching with various active layer donor materials, so that a high-efficiency organic solar cell device is formed; in addition, the organic solar cell printing ink can be widely applied to an upright device structure, an inverted device structure and a series laminated device structure of an organic solar cell, and can realize large-area printing preparation of the organic solar cell.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without inventive exercise. Wherein:

FIG. 1 is a 1H NMR spectrum of a compound S-6 in example 3 of the present invention.

FIG. 2 is a 13C NMR spectrum of compound S-6 in example 3 of the present invention.

FIG. 3 is a UV-VIS absorption spectrum curve of compound S-6 in example 3 of the present invention.

Fig. 4 is a schematic structural diagram of an organic solar device in example 17 of the present invention.

FIG. 5 is a diagram showing the preparation steps of the S-1 compound in example 1 of the present invention.

FIG. 6 is a diagram showing the preparation process of the S-5 compound in example 2 of the present invention.

FIG. 7 is a diagram showing the preparation process of the S-6 compound in example 3 of the present invention.

FIG. 8 is a diagram showing the preparation process of the S-8 compound in example 4 of the present invention.

FIG. 9 is a diagram showing the preparation process of the S-9 compound in example 5 of the present invention.

FIG. 10 is a diagram showing the preparation process of the S-11 compound in example 6 of the present invention.

FIG. 11 is a diagram showing the preparation process of the S-15 compound in example 7 of the present invention.

FIG. 12 is a diagram showing the preparation process of the S-16 compound in example 8 of the present invention.

FIG. 13 is a diagram showing the preparation process of the compound S-17 in example 9 of the present invention.

FIG. 14 is a diagram showing the preparation process of the S-18 compound in example 10 of the present invention.

FIG. 15 is a diagram showing the preparation process of the compound S-19 in example 11 of the present invention.

FIG. 16 is a diagram showing the preparation process of the S-20 compound in example 12 of the present invention.

FIG. 17 is a diagram showing the preparation process of the compound S-21 in example 13 of the present invention.

FIG. 18 is a diagram showing the preparation process of the S-23 compound in example 14 of the present invention.

FIG. 19 is a diagram showing the preparation process of the compound S-24 in example 15 of the present invention.

FIG. 20 is a diagram showing the preparation process of the S-28 compound in example 16 of the present invention.

Detailed Description

In order to make the aforementioned objects, features and advantages of the present invention more comprehensible, specific embodiments thereof are described in detail below with reference to examples of the specification.

In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention, but the present invention may be practiced in other ways than those specifically described and will be readily apparent to those of ordinary skill in the art without departing from the spirit of the present invention, and therefore the present invention is not limited to the specific embodiments disclosed below.

Furthermore, reference herein to "one embodiment" or "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one implementation of the invention. The appearances of the phrase "in one embodiment" in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments.

The non-fullerene electron acceptor provided in this embodiment may have the following structure:

example 1

The preparation of the S-1 compound is shown in FIG. 5.

The method comprises the following specific steps:

step I: 3-methylthiophene (L-1) (678.3mg, 6.91mmol), N-dimethylformamide (655.7mg, 8.97mmol) (a) and phosphorus oxychloride (1269.6mg, 8.28mmol) were placed in a three-port reaction flask, 20mL of 1, 2-dichloroethane was extracted and injected therein, each injection port was coated with vaseline and closed, and the reaction was carried out at 100 ℃ for 24 hours. The resulting mother liquor was washed with water, extracted with dichloromethane, dried over anhydrous sodium sulfate, and then the excess solvent was distilled off by reduced pressure distillation and purified by silica gel chromatography to give b (424.6mg, 48.7%).

Step II: b (386.2mg, 3.061mmol) is put into a two-mouth reaction bottle, 15mL of dichloromethane is extracted by a syringe and injected into the reaction bottle, the whole reaction bottle body is wrapped by tinfoil paper and protected from light, and the reaction bottle is put into an ice water bath and stirred. N-bromosuccinimide (c) (704.6mg, 3.982mmol) was dissolved in 10mL DMF and the solution was injected dropwise into a reaction flask, the reaction was stirred overnight, the resulting product was washed with water and extracted with dichloromethane, excess solvent was removed by distillation under reduced pressure after removal of water with anhydrous sodium sulfate, and purified by silica gel chromatography (PE: DCM ═ 3: 1) to give d (598.8mg, 95.4%).

IIIThe method comprises the following steps: d (537.5mg, 2.621mmol) was reacted with 2,5,8- (trimethylstannyl) benzo [1,2-b:3,4-b':5,6-b ″)]Trithiophene (e) (583.4mg, 0.794mmol), tetrabutylammonium bromide (142.8mg, 0.443mmol), and Pd (PPh)₃)₄(10mg, 0.008mmol) was placed in a reaction flask, nitrogen was purged 3-4 times, 30mL of nitrogen-bubbled toluene was added, and the mixture was stirred at 90 ℃ and condensed under reflux for 36 h. After completion of the reaction, the mother liquor was repeatedly extracted with water and dichloromethane several times, and after water was taken out with anhydrous sodium sulfate, excess solvent was removed by rotary evaporation and purified by silica gel column chromatography (PE: DCM ═ 1: 3) to give f (169.5mg, 34.5%).

Step IV: f (130.6mg, 0.211mmol) and 5, 6-difluoro-3- (dicyanomethylene) indolone (g) (177.0mg, 0.769mmol) were placed in a single-neck reaction flask, dissolved in 15mL of chloroform, and three drops of pyridine were added with stirring, stirred at 100 ℃ and condensed overnight. After completion of the reaction, purification was performed by silica gel chromatography (PE: DCM ═ 1: 1) to give S-1(243.4mg, 91.9%) after spin-drying.

Compound S-1 product MS (m/z): 1254.01, respectively; elemental analysis (C)₆₆H₂₄F₆N₆O₃S₆):C,63.15；H,1.93；F,9.08；N,6.69；O,3.82；S,15.32.

Example 2

The preparation of the S-5 compound is shown in FIG. 6.

Formula S-5 is prepared in analogy to the preparation of compound S-1, except that L-5 is used instead of 3-methylthiophene (L-1). The yield in the first step was 42.1%, the yield in the second step was 92.8%, the yield in the third step was 33.5%, and the yield in the fourth step was 92.3%.

Compound S-5 product MS (m/z): 1933.19; elemental analysis (C)₁₀₅H₅₄F₆N₁₂O₃S₉):C,65.20；H,2.81；F,5.89；N,8.69；O,2.48；S,14.92.

Example 3

The preparation of the S-6 compound is shown in FIG. 7.

Formula S-6 is prepared in analogy to the preparation of compound S-1, except that L-6 is used instead of 3-methylthiophene (L-1). The yield in the first step was 44.5%, the yield in the second step was 95.6%, the yield in the third step was 35.7%, and the yield in the fourth step was 94.2%.

Compound S-6 product MS (m/z): 4017.37; elemental analysis (C)₂₅₅H₂₂₈F₆N₆O₃S₁₅):C,76.20；H,5.72；F,2.84；N,2.09；O,1.19；S,11.96.

Example 4

The preparation of the S-8 compound is shown in FIG. 8.

Formula S-8 is prepared in analogy to the preparation of compound S-1, except that L-8 is used instead of 3-methylthiophene (L-1). The yield in the first step was 42.8%, the yield in the second step was 91.3%, the yield in the third step was 34.4%, and the yield in the fourth step was 93.1%.

Compound S-8 product MS (m/z): 3994.01; elemental analysis (C)₂₅₅H₃₀₀F₆N₆O₃S₁₂):C,76.65；H,7.57；F,2.85；N,2.10；O,1.20；S,9.63.

Example 5

The preparation of the S-9 compound is shown in FIG. 9.

Formula S-9 is prepared in analogy to the preparation of compound S-1, except that L-9 is used instead of 3-methylthiophene (L-1). The yield in the first step was 41.5%, the yield in the second step was 92.6%, the yield in the third step was 34.8%, and the yield in the fourth step was 91.5%.

Compound S-9 product MS (m/z): 4041.83; elemental analysis (C)₂₅₂H₂₈₈F₆N₆O₃S₁₅):C,74.85；H,7.18；F,2.82；N,2.08；O,1.19；S,11.89.

Example 6

The preparation of the S-11 compound is shown in FIG. 10.

Formula S-11 is prepared in analogy to the preparation of compound S-1, except that L-11 is used instead of 3-methylthiophene (L-1). The yield in the first step was 42.9%, the yield in the second step was 91.7%, the yield in the third step was 33.6%, and the yield in the fourth step was 92.4%.

Compound S-11 product MS (m/z): 2107.07; elemental analysis (C)₁₀₅H₄₈F₆N₁₈O₃S₁₂):C,59.82；H,2.29；F,5.41；N,11.96；O,2.28；S,18.25.

Example 7

The preparation of the S-15 compound is shown in FIG. 11.

Formula S-15 is prepared in analogy to the preparation of compound S-1, except that L-15 is used instead of 3-methylthiophene (L-1). The yield in the first step was 43.8%, the yield in the second step was 92.4%, the yield in the third step was 34.7%, and the yield in the fourth step was 94.1%.

Compound S-15 product MS (m/z): 2350.25; elemental analysis (C)₁₂₀H₆₉F₆N₂₁O₃S₁₂):C,61.29；H,2.96；F,4.85；N,12.51；O,2.04；S,16.36.

Example 8

The preparation of the S-16 compound is shown in FIG. 12.

Formula S-16 is prepared in analogy to the preparation of compound S-1, except that L-16 is used instead of 3-methylthiophene (L-1). The yield in the first step was 42.7%, the yield in the second step was 92.2%, the yield in the third step was 33.9%, and the yield in the fourth step was 93.4%.

Compound S-16 product MS (m/z): 2671.35; elemental analysis (C)₁₄₇H₉₆F₆N₁₂O₃S₁₅):C,66.04；H,3.62；F,4.26；N,6.29；O,1.80；S,17.99.

Example 9

The preparation of the S-17 compound is shown in FIG. 13.

Formula S-17 is prepared in a similar manner to compound S-1, except that L-17 is used instead of 3-methylthiophene (L-1) and g-17 is used instead of g. The yield in the first step was 43.1%, the yield in the second step was 91.6%, the yield in the third step was 32.9%, and the yield in the fourth step was 92.9%.

Compound S-17 product MS (m/z): 1821.17; elemental analysis (C)₁₀₂H₆₀C_l6N₆O₉S₃):C,67.22；H,3.32；Cl,11.67；N,4.61；O,7.90；S,5.28.

Example 10

The preparation of the S-18 compound is shown in FIG. 14.

Formula S-18 is prepared in a similar manner to the preparation of compound S-1, except that L-18 is used instead of 3-methylthiophene (L-1) and g-18 is used instead of g. The yield in the first step was 42.7%, the yield in the second step was 91.9%, the yield in the third step was 31.8%, and the yield in the fourth step was 91.7%.

Compound S-18 product MS (m/z): 2181.93, respectively; elemental analysis (C)₁₁₄H₆₃Br₆N₉O₃S₃)：C,62.74；H,2.91；Br,21.97；N,5.78；O,2.20；S,4.41.

Example 11

The preparation of the S-19 compound is shown in FIG. 15.

Formula S-19 is prepared in a similar manner to compound S-1, except that L-19 is used instead of 3-methylthiophene (L-1) and g-19 is used instead of g. The yield in the first step was 42.6%, the yield in the second step was 91.6%, the yield in the third step was 31.9%, and the yield in the fourth step was 91.4%.

Compound S-19 product MS (m/z): 2712.70; elemental analysis (C)₁₁₁H₆₆I₆N₁₂O₆S₉):C,49.13；H,2.45；I,28.06；N,6.19；O,3.54；S,10.63.

Example 12

The preparation of the S-20 compound is shown in FIG. 16.

Formula S-20 is prepared in a similar manner to the preparation of compound S-1, except that L-20 is used instead of 3-methylthiophene (L-1) and g-20 is used instead of g. The yield in the first step was 42.8%, the yield in the second step was 91.3%, the yield in the third step was 31.7%, and the yield in the fourth step was 91.5%.

Compound S-20 product MS (m/z): 4522.83; elemental analysis (C)₂₈₅H₂₉₄N₆O₁₅S₁₅):C,75.66；H,6.55；N,1.86；O,5.30；S,10.63.

Example 13

The preparation of the S-21 compound is shown in FIG. 17.

Formula S-21 is prepared in a similar manner to the preparation of compound S-1, except that L-21 is used instead of 3-methylthiophene (L-1) and g-21 is used instead of g. The yield in the first step was 42.9%, the yield in the second step was 91.2%, the yield in the third step was 31.9%, and the yield in the fourth step was 91.6%.

Compound S-21 product MS (m/z): 3685.79; elemental analysis (C)₂₂₈H₂₇₀N₆O₁₉S₉):C,74.27；H,7.38；N,2.28；O,8.24；S,7.83.

Example 14

The preparation of the S-23 compound is shown in FIG. 18.

Formula S-23 is prepared in a similar manner to compound S-1, except that L-23 is used in place of 3-methylthiophene (L-1) and g-23 is used in place of g. The yield in the first step was 41.7%, the yield in the second step was 92.2%, the yield in the third step was 32.3%, and the yield in the fourth step was 91.1%.

Compound S-23 product MS (m/z): 2600.90; elemental analysis (C)₁₁₇H₇₂Br₃C_l3N₁₈O₉S₁₂):C,53.95；H,2.79；Br,9.20；Cl,4.08；N,9.68；O,5.53；S,14.77.

Example 15

The preparation of the S-24 compound is shown in FIG. 19.

Formula S-24 is prepared in a similar manner to the preparation of compound S-1, except that L-24 is used instead of 3-methylthiophene (L-1) and g-24 is used instead of g. The yield in the first step was 41.8%, the yield in the second step was 92.9%, the yield in the third step was 32.6%, and the yield in the fourth step was 91.5%.

Compound S-23 product MS (m/z): 3262.30; elemental analysis (C)₁₅₃H₁₂₆I₃N₂₁O₉S₁₅):C,56.29；H,3.89；I,11.66；N,9.01；O,4.41；S,14.73.

Example 16

The preparation of the S-28 compound is shown in FIG. 20.

Formula S-28 is prepared in a similar manner to the preparation of compound S-1, except that L-28 is used instead of 3-methylthiophene (L-1) and g-28 is used instead of g. The yield in the first step was 41.9%, the yield in the second step was 92.6%, the yield in the third step was 32.7%, and the yield in the fourth step was 91.8%.

Compound S-28 product MS (m/z): 2971.56; elemental analysis (C)₁₇₁H₁₂₆N₁₂O₉S₁₅):C,69.06；H,4.27；N,5.65；O,4.84；S,16.17.

Example 17

Preparing an organic solar cell device:

the preparation process of the organic solar cell device comprises the following steps: the device structure is Indium Tin Oxide (ITO)/ZnO/PBDB-T: S-1/MoO₃and/Ag. The sheet resistance of the OPV device substrate was 15 ohm/square.

Substrate using ITCleaning with O cleaning solution for 10min, ultrasonic cleaning for 30min, cleaning with deionized water for 10min, cleaning with acetone for 10min, cleaning with isopropanol for 10min, and blow-drying with nitrogen gas. An 80mg/mL ZnO solution was spin-coated on an ITO substrate at a speed of 4500r/min for 1min, and then annealed at a temperature of 200 ℃ in air for 1 h. Subsequently, the substrate was transferred into a glove box of a nitrogen atmosphere (water oxygen content was less than 0.1ppm each). The configuration of the standard active layer in chlorobenzene was: PBDB-T: S-1: 1.2, giving the recipient a concentration of 20mg/mL in chlorobenzene. The prepared active layer solution is uniformly spin-coated on the prepared substrate at the rotating speed of 2000 r/min. Spin coating active layer, transferring into channel of glove box, pumping for 30min, transferring into evaporation instrument, evaporating to form a 10nm MoO3 hole transport layer, evaporating to form an Ag electrode with thickness of 100nm and pressure of 1 × 10^-6bar. The area of the cell was 0.04cm². Finally, the current-voltage (J-V) curves were tested using a Keithley 2400 workstation, using a Newport thermo Oriel 91192 model solar simulator (AM1.5G, 100 mW/cm)²) A test of the photocurrent was performed. Decomposition temperature (Td) of the film, molar extinction coefficient (. epsilon.)_max) Electron mobility (μ)_e) Short-circuit current (J)_sc) Open circuit voltage (V)_oc) The Fill Factor (FF) results are shown in Table 1.

Example 18

Preparing an organic solar cell device:

an organic solar cell device was produced in the same manner as in example 2-1, except that each compound described in table 2 was used instead of the compound S-1 as a non-fullerene electron acceptor. The organic solar cell device thus obtained was measured for its decomposition temperature (Td) and molar extinction coefficient (. epsilon.) in the same manner as in example 2-1_max) Electron mobility (μ)_e) Short-circuit current (J)_sc) Open circuit voltage (V)_oc) Fill Factor (FF), results are shown in Table 1.

TABLE 1

As can be seen from Table 1, the non-fullerene electron acceptor has conjugated and rigid structure due to the benzotrithiophene core unit, and in addition, the aromatic or heteroaromatic condensed rings on the arm units enlarge the planar pi conjugation effect, the film decomposition temperature is higher and is above 360 ℃, and the film has good thermal stability. The molar extinction coefficients are all 2.30 multiplied by 10⁵M^-1cm^-1And the material has high sensitivity to light materials such as sunlight and strong light absorption capacity. The electron mobility is 3 x 10^-4cm²V^{- 1}s^-1And has high charge mobility. The short-circuit current exceeds 10mA/cm²The open circuit voltage is around 1V, and the filling factor is above 60%, which shows that the device efficiency is excellent. .

Comparative example 1

Under the conditions of example 1, the preparation parameters were controlled differently as follows:

the method comprises the following specific steps:

step I: 3-methylthiophene (L-1) (1567.4mg, 15.97mmol), N-dimethylformamide (3502.2mg, 47.91mmol) (a) and phosphorus oxychloride (2934.8mg, 19.14mmol) are put into a three-port reaction bottle, 50mL of 1, 2-dichloroethane is extracted and injected into the three-port reaction bottle, each injection port is coated and sealed with vaseline, and the reaction is carried out for 24 hours at the temperature of 100 ℃. The resulting mother liquor was washed with water, extracted with dichloromethane, dried over anhydrous sodium sulfate, and then the excess solvent was distilled off by reduced pressure distillation and purified by silica gel chromatography to give b (284.1mg, 14.1%).

Step II: b (276.6mg, 2.192mmol) is put into a two-mouth reaction bottle, 25mL of dichloromethane is extracted by a syringe and injected into the reaction bottle, the whole reaction bottle body is wrapped by tinfoil paper and protected from light, and the reaction bottle is put into an ice water bath and stirred. N-bromosuccinimide (c) (2113.8mg, 6.576mmol) was dissolved in 30ml dmf and the solution was injected dropwise into a reaction flask, the reaction was stirred overnight, the resulting product was washed with water and extracted with dichloromethane, excess solvent was removed by distillation under reduced pressure after removal of water with anhydrous sodium sulfate, and purified by silica gel chromatography (PE: DCM ═ 3: 1) to give d (296.2mg, 65.9%).

Step III: d (287.5mg, 1.402mmol) is reacted with 2,5,8- (trimethylstannyl) benzo [1,2-b:3,4-b':5,6-b ″)]Trithiophene (e) (147.7mg, 0.201mmol), tetrabutylammonium bromide (71.4mg, 0.222mmol), and Pd (PPh)₃)₄(5mg, 0.004mmol) was placed in a reaction flask, nitrogen was purged 3-4 times, 30mL of nitrogen-bubbled toluene was added, and the mixture was stirred at 90 ℃ and condensed under reflux for 36 h. After completion of the reaction, the mother liquor was repeatedly extracted with water and dichloromethane several times, and after water was taken out with anhydrous sodium sulfate, excess solvent was removed by rotary evaporation and purified by silica gel column chromatography (PE: DCM ═ 1: 3) to give f (20.5mg, 16.5%).

Step IV: f (20.2mg, 0.033mmol) and 5, 6-difluoro-3- (dicyanomethylene) indolone (g) (68.4mg, 0.297mmol) were placed in a single-neck reaction flask, dissolved in 10mL of chloroform, added with three drops of pyridine under stirring, stirred at 100 ℃ and condensed overnight. After completion of the reaction, purification was performed by silica gel chromatography (PE: DCM ═ 1: 1) to give S-1(31.0mg, 74.8%) after spin-drying.

Compound S-1 product MS (m/z): 1254.01, respectively; elemental analysis (C)₆₆H₂₄F₆N₆O₃S₆):C,63.15；H,1.93；F,9.08；N,6.69；O,3.82；S,15.32.

The lower yield in step I compared to example 1-1 is due, on the one hand, to the formation of more by-products:

on the other hand, too large molar feeding proportion can also cause raw materials with less components to be wrapped, which is not beneficial to uniform stirring, thus being not beneficial to reaction and influencing yield.

The reason that the yield in the steps II, III and IV is low is mainly that the raw materials with less components are wrapped by overlarge molar feeding proportion, and the stirring is not facilitated, so that the reaction is not facilitated, and the yield is reduced.

The invention discloses a preparation method of a non-fullerene electron acceptor, a product and application thereof, wherein the material takes a benzotrithiophene electron donating group as a central unit, a condensed ring structure as an arm unit, hetero atoms introduced on the condensed ring are modified by adopting side groups, and the end groups are blocked by using 3- (dicyanomethylene) indolone groups and derivatives thereof, so as to obtain the non-fullerene electron acceptor material. The material adopts an aromatic or heteroaromatic condensed ring enlarged plane pi conjugated skeleton as an arm unit, promotes pi electron delocalization and molecular accumulation, is used as a part of a plane skeleton, has a condensed ring structure capable of promoting red shift absorption, reducing ionization energy, increasing crystallinity and the like, introduces a pi-extended conjugated structure and a condensed ring core rich in a thiophene structure into a star structure, not only maintains the advantages of strong absorption of a linear structure, easy modification, good thermal stability, strong electron donating capability, good rigidity and the like, but also shows extended absorption, reduced band gap and increased mobility, thereby remarkably improving the performance of an organic solar cell device.

It should be noted that the above-mentioned embodiments are only for illustrating the technical solutions of the present invention and not for limiting, and although the present invention has been described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that modifications or equivalent substitutions may be made on the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, which should be covered by the claims of the present invention.