CN116606304A - High-charge-density organic semiconductor molecule and preparation method and application thereof - Google Patents

Abstract

The application provides a high-charge-density organic semiconductor molecule, a preparation method and application thereof, and belongs to the technical field of organic semiconductors. The palladium-catalyzed cross-coupling reaction is utilized to realize different substitution positions of F atoms of the parent molecule of the 2, 6-diphenyl dithiophene [3,2-B:2',3' -D ] thiophene, and the fact that the different substitution positions of F atoms can regulate the charge density of a semiconductor is verified. It was further demonstrated through experimentation that F-S interactions are one of the reasons for this phenomenon. The preparation method is simple, and the organic semiconductor molecules with high charge density prepared by the method can adjust the threshold voltage of the device when the organic field effect transistor is prepared, and have potential application in various fields such as temperature sensing, light detection, data storage and the like.

Description

A kind of high charge density organic semiconductor molecule and its preparation method and application

technical field

The invention belongs to the technical field of organic semiconductors, and in particular relates to a high charge density organic semiconductor molecule and its preparation method and application.

Background technique

The semiconductor material industry is a strategic basic industry that supports economic development. With the development of flexible electronic devices, organic semiconductors have attracted extensive attention due to their many advantages such as high solubility, low cost, flexible molecular design, and mechanical flexibility. Flexible optoelectronic devices using organic semiconductors as active materials have developed rapidly, and their performance has been significantly improved. At present, it has been successfully applied to many fields such as organic field effect transistors, organic light-emitting diodes, and organic solar cells.

As the core component of semiconductor devices, organic semiconductors have been widely concerned about their physical and chemical properties. After nearly half a century of exploration, the design strategies for organic semiconductor materials in the prior art mainly include (1) the adjustment of the energy level of the material by the PN junction or the donor-acceptor structure; (2) the use of covalent bonds to form fused rings Change the rigidity of molecules; (3) Realize the adjustment of the spatial structure of materials through intermolecular/intramolecular interactions; (4) Use heteroatoms to functionalize materials. As an important physical parameter to adjust the carrier concentration, the charge density has been widely concerned by researchers. However, the traditional adjustment method is mainly realized by doping, and the preparation method is relatively complicated. Based on this, the present invention proposes a high-charge-density organic semiconductor molecule and its preparation method, which makes up for the gap in the research field of adjusting material charge density through molecular design rules.

Contents of the invention

In order to solve the above technical problems, the present invention proposes a high charge density organic semiconductor molecule and its preparation method and application.

To achieve the above object, the present invention provides the following technical solutions:

The present invention proposes a high-charge-density organic semiconductor molecule, the high-charge-density organic semiconductor molecule is a parent molecule that is ortho-substituted by an F atom, and the parent molecule includes 2,6-diphenyldithiophene[3,2-B :2',3'-D]thiophene, 2,5-diphenylthiophene[3,2-b]thiophene, 2,6-diphenylbenzo[1,2-b:4,5-b' ]dithiophene, 1,4-bis(5-phenylthiophene-2-yl)benzene or 5,5"-diphenyl-2,2':5',2"-trithiophene.

The present invention also proposes a method for preparing the above-mentioned high-charge-density organic semiconductor molecule, which utilizes palladium-catalyzed cross-coupling reaction to realize the ortho-position substitution of the F atom of the parent molecule, comprising the following steps:

The compound, 2-fluorophenylboronic acid, catalyst, and potassium carbonate were refluxed and stirred in a mixed solvent. After the reaction, suction filtration and drying were performed to obtain a yellow solid powder, and the yellow solid powder was separated by column chromatography. After standing still, the high Charge Density Organic Semiconductor Molecules.

Further, the compound includes 2,5-dibromodithieno[3,2-B:2',3'-D]thiophene.

Further, the catalyst is palladium tetrakistriphenylphosphine.

Further, the molar ratio of the compound to 2-fluorophenylboronic acid, catalyst and potassium carbonate is 2:4.2:0.12:8.

Further, the mixed solvent is composed of toluene, ethanol and water in a volume ratio of 4:1:1, and the volume molar ratio of the mixed solvent to the compound is 12mL:2mmol.

Further, the reflux stirring time is 12h.

Further, the column chromatography separation adopts petroleum ether and ethyl acetate in a volume ratio of 10:1.

The invention also proposes the application of the high charge density organic semiconductor molecules in the preparation of organic field effect transistors.

Compared with the prior art, the present invention has the following advantages and technical effects:

(1) The present invention utilizes palladium-catalyzed cross-coupling reaction to design and synthesize semiconductor molecules, the preparation method is simple, and the organic semiconductor molecules obtained with high charge density can adjust the threshold voltage of the device when preparing organic field effect transistors, in temperature sensing, It has potential applications in many fields such as photodetection and data storage. At the same time, it is found that the charge density of organic semiconductor materials can be adjusted by using the difference in the substitution position of F atoms.

Description of drawings

The drawings constituting a part of the application are used to provide further understanding of the application, and the schematic embodiments and descriptions of the application are used to explain the application, and do not constitute an improper limitation to the application. In the attached picture:

Fig. 1 is the nuclear magnetic resonance spectrogram of the product prepared in embodiment 1;

Fig. 2 is the high-resolution mass spectrogram of the product prepared in embodiment 1, wherein a is a liquid phase chromatogram, and b is a mass spectrogram;

Fig. 3 is the nuclear magnetic resonance spectrogram of the product prepared in comparative example 1;

Fig. 4 is the high-resolution mass spectrum of the product prepared in Comparative Example 1, wherein a is a liquid phase chromatogram, and b is a mass spectrum;

Fig. 5 is the nuclear magnetic resonance spectrogram of the product prepared in comparative example 2;

Fig. 6 is the high-resolution mass spectrum of the product prepared in comparative example 2, wherein a is a liquid phase chromatogram, and b is a mass spectrum;

Fig. 7 is the nuclear magnetic resonance spectrogram of the product prepared in comparative example 3;

Fig. 8 is the high-resolution mass spectrum of the product prepared in comparative example 3, wherein a is a liquid phase chromatogram, and b is a mass spectrum;

Fig. 9 is the synthesis process of organic semiconductor molecules in Example 1 and Comparative Examples 1-3;

Figure 10 is a crystal structure diagram of organic semiconductor molecules in Example 1 and Comparative Examples 1-3, wherein (a) is Example 1, (b) is Comparative Example 1, (c) is Comparative Example 3, and (d) is Comparative example 4;

Fig. 11 is the electrical performance test result of the single crystal device prepared using the organic semiconductor molecule of Example 1;

Fig. 12 is the electrical performance test result of the single crystal device prepared using the organic semiconductor molecule of Comparative Example 1;

Figure 13 is the electrical performance test result of the single crystal device prepared using the organic semiconductor molecule of Comparative Example 2;

Figure 14 is the electrical performance test result of the single crystal device prepared using the organic semiconductor molecules of Comparative Example 3;

Fig. 15 is the X-ray photoelectron energy spectrum diagram of the organic semiconductor molecules prepared in Example 1 and Comparative Examples 1-3, wherein (a) is Example 1, (b) is Comparative Example 1, (c) is Comparative Example 3, (d) is comparative example 4.

Detailed ways

Various exemplary embodiments of the present invention will now be described in detail. The detailed description should not be considered as a limitation of the present invention, but rather as a more detailed description of certain aspects, features and embodiments of the present invention.

It should be understood that the terminology described in the present invention is only used to describe specific embodiments, and is not used to limit the present invention. In addition, regarding the numerical ranges in the present invention, it should be understood that each intermediate value between the upper limit and the lower limit of the range is also specifically disclosed. Each smaller range between any stated value or intervening value in a stated range and any other stated value or intervening value in a stated range is encompassed within the invention. The upper and lower limits of these smaller ranges may independently be included or excluded from the range.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Although only the preferred methods and materials are described herein, any methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present invention. All documents mentioned in this specification are incorporated by reference to disclose and describe the methods and/or materials in connection with which the documents are described. In case of conflict with any incorporated document, the contents of this specification control.

It will be apparent to those skilled in the art that various modifications and changes can be made in the specific embodiments of the present invention described herein without departing from the scope or spirit of the present invention. Other embodiments will be apparent to the skilled person from the description of the present invention. The description and examples of the invention are illustrative only.

As used herein, "comprising", "comprising", "having", "comprising" and so on are all open terms, meaning including but not limited to.

The present invention proposes a high-charge-density organic semiconductor molecule, the high-charge-density organic semiconductor molecule is a parent molecule that is ortho-substituted by an F atom, and the parent molecule includes 2,6-diphenyldithiophene[3,2-B :2',3'-D]thiophene (structural formula: ), 2,5-diphenylthiophene[3,2-b]thiophene (structural formula: ), 2,6-diphenylbenzo[1,2-b:4,5-b']dithiophene (structural formula: ), 1,4-bis(5-phenylthiophene-2-yl)benzene (structural formula: /> ) or 5,5"-diphenyl-2,2':5',2"-trithiophene (structural formula: /> ).

The present invention also proposes a method for preparing the above-mentioned high-charge-density organic semiconductor molecule, which utilizes palladium-catalyzed cross-coupling reaction to realize the ortho-position substitution of the F atom of the parent molecule, comprising the following steps:

The compound, 2-fluorophenylboronic acid, catalyst, and potassium carbonate were refluxed and stirred in a mixed solvent. After the reaction, suction filtration and drying were performed to obtain a yellow solid powder, and the yellow solid powder was separated by column chromatography. After standing still, the high Charge Density Organic Semiconductor Molecules.

In an embodiment of the present invention, the compound includes 2,5-dibromodithieno[3,2-B:2',3'-D]thiophene (structural formula: ), but not limited to 2,5-dibromodithieno[3,2-B:2',3'-D]thiophene, for example, when the F atom is ortho-substituted with 2,5-diphenylthiophene[3, 2-b]thiophene, 2,6-diphenylbenzo[1,2-b:4,5-b']dithiophene, 1,4-bis(5-phenylthiophene-2-yl)benzene or 5,5”-diphenyl-2,2’:5’,2”-trithiophene, the compound needs to be changed accordingly.

In the embodiment of the present invention, the catalyst is palladium tetrakistriphenylphosphine.

In the embodiment of the present invention, the molar ratio of the compound to 2-fluorophenylboronic acid, catalyst and potassium carbonate is 2:4.2:0.12:8.

In the embodiment of the present invention, the mixed solvent is composed of toluene, ethanol and water in a volume ratio of 4:1:1, and the volume molar ratio of the mixed solvent to the compound is 12mL:2mmol.

In the embodiment of the present invention, the reflux stirring time is 12h.

In the embodiment of the present invention, petroleum ether and ethyl acetate with a volume ratio of 10:1 were used for column chromatography separation.

All the raw materials used in the examples of the present invention were purchased from the market.

In the embodiments of the present invention, room temperature refers to 25±2°C.

The technical solution of the present invention will be further described below through examples.

Example 1

Preparation of 2,6-bis(2-fluorophenyl)dithiophene[3,2-B:2',3'-D]thiophene:

0.71g 2,5-dibromodithieno[3,2-B:2',3'-D]thiophene (2mmol), 0.59g 2-fluorophenylboronic acid (4.2mmol), 0.14g tetratriphenyl Phosphine palladium (0.12mmol) and 1.10g potassium carbonate (8mmol) were put into two-necked flasks, vacuum nitrogen was replaced three times, and 12mL of mixed solvent composed of toluene, ethanol and water with a volume ratio of 4:1:1 was injected by syringe Add it into a two-neck flask, reflux and stir for 12 hours, use thin-layer chromatography to trace the complete reaction of the raw materials, then cool to room temperature, filter with suction, and dry to obtain a yellow solid powder. Afterwards, the yellow solid powder was separated by column chromatography with petroleum ether and ethyl acetate at a volume ratio of 10:1. After standing for 30 minutes, a large amount of yellow flocculent solids were precipitated, and finally yellow flocculent crystals were obtained, namely 2, 6-bis(2-fluorophenyl)dithiophene[3,2-B:2',3'-D]thiophene. After testing, the yield: 76%. ¹ H NMR (600MHz, DMSO-d ₆ )δ8.04(s, 2H), 7.83(t, J=7.8Hz, 2H), 7.39(dt, J=16.4, 9.3Hz, 4H), 7.30(t, J＝7.3Hz, 2H). HRMS (ESI) theoretical m/z: 383.99, measured m/z: [M+H ⁺ ]: 384.9989.

The NMR spectrum of the product prepared in Example 1 is shown in Figure 1; the high-resolution mass spectrum is shown in Figure 2, wherein a is a liquid chromatography spectrum, and b is a mass spectrum;

From the nuclear magnetic resonance spectrum and high-resolution mass spectrum in Figure 1 and Figure 2, the molecular structure is clearly analyzed, and the X-single crystal ray diffractometer verifies the substitution position of the F atom, thereby confirming that the product prepared in Example 1 is 2, which is substituted by the ortho position of the F atom. 6-bis(2-fluorophenyl)dithiophene[3,2-B:2',3'-D]thiophene.

Comparative example 1 (no F atom substitution)

Preparation of 2,6-diphenyldithiophene[3,2-B:2',3'-D]thiophene:

0.71 g 2,5-dibromodithieno[3,2-B:2′,3′-D]thiophene (2 mmol), 0.24 g phenylboronic acid (4.2 mmol), 0.14 g tetrakistriphenylphosphine palladium ( 0.12mmol) and 1.10g potassium carbonate (8mmol) were put into a two-necked flask, replaced with vacuum nitrogen three times, and 12mL of a mixed solvent composed of toluene, ethanol and water with a volume ratio of 4:1:1 was added to the two-necked flask by injecting with a syringe. , after reflux and stirring for 12 hours, the reaction of the raw materials was traced by thin layer chromatography, then cooled to room temperature, suction filtered, and dried to obtain a light gray solid powder. After that, the light gray solid powder was separated by column chromatography with petroleum ether and ethyl acetate with a volume ratio of 8:1. After standing for 30 minutes, a large amount of yellow flocculent solids were precipitated, and finally yellow flocculent crystals were obtained, which was 2 ,6-Diphenyldithiophene[3,2-B:2',3'-D]thiophene. After testing, the yield: 82%. ¹ H NMR (600MHz, DMSO-d ₆ )δ7.83(d, J=5.7Hz, 2H), 7.68(s, 4H), 7.44(d, J=7.9Hz, 4H), 7.33(s, 2H) .HRMS (ESI) theoretical m/z: 348.01, measured m/z: [M+H ⁺ ]: 349.0176.

The nuclear magnetic resonance spectrum of the product prepared in Comparative Example 1 is shown in Figure 3; the high-resolution mass spectrum is shown in Figure 4, wherein a is a liquid chromatography spectrum, and b is a mass spectrum;

The nuclear magnetic resonance spectrum of Fig. 3 and Fig. 4, high-resolution mass spectrometry clearly analyze molecular structure, thus confirm that the product prepared in comparative example 1 is 2,6-diphenyldithiophene [3,2-B: 2',3'-D]thiophene.

Comparative example 2 (meta substitution of F atom)

Preparation of 2,6-bis(3-fluorophenyl)dithiophene[3,2-B:2',3'-D]thiophene:

0.71g 2,5-dibromodithieno[3,2-B:2',3'-D]thiophene (2mmol), 0.59g 3-fluorophenylboronic acid (4.2mmol), 0.14g tetratriphenyl Phosphine palladium (0.12mmol) and 1.10g potassium carbonate (8mmol) were put into two-necked flasks, vacuum nitrogen was replaced three times, and 12mL of mixed solvent composed of toluene, ethanol and water with a volume ratio of 4:1:1 was injected by syringe Add it into a two-necked flask, reflux and stir for 12 hours, use thin-layer chromatography to trace the complete reaction of the raw materials, then cool to room temperature, filter with suction, and dry to obtain a light gray solid powder. Afterwards, the light gray solid powder was separated by column chromatography with petroleum ether and ethyl acetate at a volume ratio of 15:1. After standing for 30 minutes, a large amount of yellow flocculent solids were precipitated, and finally yellow flocculent crystals were obtained, namely 2 ,6-bis(3-fluorophenyl)dithiophene[3,2-B:2',3'-D]thiophene. After testing, the yield: 89%. ¹ H NMR (600MHz, DMSO-d ₆ )δ7.97(d, J=4.2Hz, 2H), 7.51(d, J=10.9Hz, 6H), 7.14(t, J=8.5Hz, 2H).HRMS (ESI) Theoretical m/z: 383.99, Measured m/z: [M+H ⁺ ]: 384.9989.

The NMR spectrum of the product prepared in Comparative Example 2 is shown in Figure 5; the high-resolution mass spectrum is shown in Figure 6, wherein a is a liquid chromatography spectrum, and b is a mass spectrum;

From the nuclear magnetic resonance spectra and high-resolution mass spectra in Figures 5 and 6, the molecular structure is clearly analyzed, and the X-single crystal ray diffractometer verifies the substitution position of the F atom, thereby confirming that the product prepared in Comparative Example 2 is 2 meta-substituted by the F atom. 6-bis(3-fluorophenyl)dithiophene[3,2-B:2',3'-D]thiophene.

Comparative example 3 (para-position substitution of F atom)

Preparation of 2,6-bis(4-fluorophenyl)dithiophene[3,2-B:2',3'-D]thiophene:

0.71g 2,5-dibromodithieno[3,2-B:2',3'-D]thiophene (2mmol), 0.59g 4-fluorophenylboronic acid (4.2mmol), 0.14g tetratriphenyl Phosphine palladium (0.12mmol) and 1.10g potassium carbonate (8mmol) were put into two-necked flasks, vacuum nitrogen was replaced three times, and 12mL of mixed solvent composed of toluene, ethanol and water with a volume ratio of 4:1:1 was injected by syringe Add it into a two-necked flask, reflux and stir for 12 hours, use thin-layer chromatography to trace the complete reaction of the raw materials, then cool to room temperature, filter with suction, and dry to obtain a light gray solid powder. Afterwards, the light gray solid powder was separated by column chromatography with petroleum ether and ethyl acetate at a volume ratio of 10:1. After standing for 30 minutes, a large amount of yellow flocculent solids were precipitated, and finally yellow flocculent crystals were obtained, namely 2 ,6-bis(4-fluorophenyl)dithiophene[3,2-B:2',3'-D]thiophene. After testing, the yield: 81%. HRMS (ESI) theoretical m/z: 383.99, measured m/z: [M+H ⁺ ]: 384.9989. ¹ H NMR (600MHz, Chloroform-d) δ7.59 (s, 4H), 7.43 (s, 2H) ,7.11(s,4H).

The nuclear magnetic resonance spectrum of the product prepared in Comparative Example 3 is shown in Figure 7; the high-resolution mass spectrum is shown in Figure 8, wherein a is a liquid chromatography spectrum, and b is a mass spectrum;

From the nuclear magnetic resonance spectra and high-resolution mass spectra in Figure 7 and Figure 8, the molecular structure was clearly analyzed, and the X-ray single crystal ray diffractometer verified the substitution position of the F atom, thereby confirming that the product prepared in Comparative Example 3 was 2, which was para-substituted by the F atom. 6-bis(4-fluorophenyl)dithiophene[3,2-B:2',3'-D]thiophene.

The synthesis process of organic semiconductor molecules in Example 1 and Comparative Examples 1-3 is shown in FIG. 9 .

The crystal structures of organic semiconductor molecules in Example 1 and Comparative Examples 1-3 are shown in Figure 10, wherein (a) is Example 1, (b) is Comparative Example 1, (c) is Comparative Example 3, and (d) is Comparative example 4.

Performance Testing

Using the method of physical vapor transport, the micro-nano crystals loaded with four kinds of semiconductor materials prepared in Example 1 and Comparative Examples 1-3 were prepared on octadecyltrichlorosilane (OTS) modified silicon wafers, and the The single crystal device was prepared by the level transfer method, and the structure of the single crystal device is gold, semiconductor material, OTS, silicon dioxide and silicon.

Agilent B1500 type electrical performance test system was used to test the electrical performance of the above four single crystal devices, the results are shown in Figures 11-14, Figure 11 is the electrical performance test results of the single crystal device prepared using the organic semiconductor molecules of Example 1, Figure 1 12 is the electrical performance test result of the single crystal device prepared using the organic semiconductor molecule of Comparative Example 1, Figure 13 is the electrical performance test result of the single crystal device prepared using the organic semiconductor molecule of Comparative Example 2, and Figure 14 is the electrical performance test result of the single crystal device prepared using the organic semiconductor molecule of Comparative Example 3 Electrical performance test results of single crystal devices prepared from organic semiconductor molecules. It can be seen from Figures 11-14 that the threshold voltage of 2,6-bis(2-fluorophenyl)dithiophene[3,2-B:2',3'-D]thiophene prepared in Example 1 of the present invention is + 60V, while the 2,6-diphenyldithiophene[3,2-B:2',3'-D]thiophene prepared in Comparative Example 1 and the 2,6-bis(3-fluorophenyl) prepared in Comparative Example 2 )dithiophene[3,2-B:2',3'-D]thiophene threshold voltage is -5V, 2,6-bis(4-fluorophenyl)dithiophene[3,2- B: 2',3'-D]thiophene threshold voltages are all +10V, which shows that 2,6-bis(2-fluorophenyl)dithiophene[3,2-B:2' substituted by ortho F atoms ,3'-D]thiophene has high conductivity.

Use formula (1) to calculate the charge density of organic semiconductor molecules:

σ＝nqμ formula (1)

In the formula, σ is the conductivity, q is the unit charge, n is the charge density, and μ is the mobility.

Calculated 2,6-bis(2-fluorophenyl)dithiophene[3,2-B:2',3'-D]thiophene (Example 1) has a high charge density, which can reach 7.5×10 ¹⁷ cm ^- The charge density of 3,2,6-diphenyldithiophene[3,2-B:2',3'-D]thiophene (Comparative Example 1) is 8.4×10 ¹² cm ^-3 , 2,6 ^- di( The charge density of 3-fluorophenyl)dithiophene[3,2-B:2',3'-D]thiophene (Comparative Example 2) is 1.4×10 ¹³ cm ^-3 , 2,6-bis(4-fluoro The charge density of phenyl)dithiophene[3,2-B:2',3'-D]thiophene (Comparative Example 3) is extremely weak, which shows that the 2,6-bis(2- Fluorophenyl)dithiophene[3,2-B:2',3'-D]thiophene has a high charge density.

The X-ray photoelectron spectra of the organic semiconductor molecules prepared in Example 1 and Comparative Examples 1-3 are shown in Figure 15, wherein (a) is Example 1, (b) is Comparative Example 1, (c) is Comparative Example 3, (d) is Comparative Example 4; it can be seen from Figures 10 and 15 that 2,6-bis(2-fluorophenyl)dithiophene[3,2-B:2',3'-D]thiophene has a high The reason for the charge density is the interaction between F-S.

Therefore, the present invention is not limited to one parent molecule of 2,6-diphenyldithiophene[3,2-B:2',3'-D]thiophene, but also includes the following parent molecule and prepares a semiconductor with high charge density Molecule: 2,5-diphenylthiophene[3,2-b]thiophene, 2,6-diphenylbenzo[1,2-b:4,5-b']dithiophene, 1,4-di (5-phenylthiophene-2-yl)benzene, 5,5"-diphenyl-2,2':5',2"-trithiophene and many other semiconductor molecules with F-S interactions.

The above are only preferred specific implementation methods of the present application, but the scope of protection of the present application is not limited thereto. Anyone skilled in the art can easily think of changes or substitutions within the technical scope disclosed in the present application. All should be covered within the scope of protection of this application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims (10)

1. A high charge density organic semiconductor molecule characterized in that the F atom is ortho-substituted with a parent molecule comprising 2, 6-diphenyl-dithiophene [3,2-B:2',3' -D ] thiophene, 2, 5-diphenyl-thiophene [3,2-B ] thiophene, 2, 6-diphenyl-benzo [1,2-B:4,5-B ' ] dithiophene, 1, 4-bis (5-phenyl-thiophen-2-yl) benzene or 5,5 "-diphenyl-2, 2':5',2" -trithiophene.

2. A method for preparing a high charge density organic semiconductor molecule according to claim 1, wherein F atom ortho-substitution of 2, 6-diphenyl-dithiophene [3,2-B:2',3' -D ] thiophene is achieved by palladium-catalyzed cross-coupling reaction.

3. The method for preparing a high charge density organic semiconductor molecule according to claim 2, comprising the steps of:

and (3) refluxing and stirring the compound, 2-fluorobenzeneboronic acid, a catalyst and potassium carbonate in a mixed solvent, carrying out suction filtration and drying after the reaction is finished to obtain yellow solid powder, separating the yellow solid powder by column chromatography, and standing to obtain the high-charge-density organic semiconductor molecule.

4. A method of preparing a high charge density organic semiconductor molecule according to claim 3, wherein said compound comprises 2, 5-dibromodithio [3,2-B:2',3' -D ] thiophene.

5. A method of preparing a high charge density organic semiconductor molecule according to claim 3, wherein said catalyst is tetrakis triphenylphosphine palladium.

6. A method of preparing a high charge density organic semiconductor molecule according to claim 3 wherein the molar ratio of said compound to 2-fluorobenzeneboronic acid, catalyst, potassium carbonate is 2:4.2:0.12:8.

7. The method for producing a high charge density organic semiconductor molecule according to claim 3, wherein said mixed solvent is composed of toluene, ethanol and water in a volume ratio of 4:1:1, and a volume molar ratio of said mixed solvent to said compound is 12 ml:2 mmol.

8. A method of preparing a high charge density organic semiconductor molecule according to claim 3, wherein said reflux stirring is for a period of 12 hours.

9. The method for producing a high charge density organic semiconductor molecule according to claim 3, wherein the column chromatography is performed using petroleum ether and ethyl acetate in a volume ratio of 10:1.

10. Use of the high charge density organic semiconductor molecule of claim 1 in the preparation of an organic field effect transistor.