Cyano-containing polythiophene-based conductive polymer, preparation method therefor and use thereof

Abstract

The present invention relates to the technical field of photoelectric devices, and discloses a cyano-containing polythiophene-based conductive polymer, a preparation method therefor and a use thereof. In the present invention, a cyano group with an aromatic bridge is introduced into a polythiophene-based conjugated backbone, and by controlling the bandgap of thieno[3,2-b]thiophene, changing the conjugation length and modifying the steric hindrance, the bottleneck of poor polymerizability in nitrile materials has been overcome, and preparation methods therefor are simple and controllable; moreover, the conductive polymer has excellent electrochemical energy storage and photoelectric properties, promotes the rapid processing and preparation of conductive polymer-based electrode materials and energy-storage applications thereof, and is a photoelectric device material having excellent performance.

Description

A cyano-containing polythiophene conductive polymer, its preparation method and application Technical Field

[0001] This invention relates to the field of optoelectronic device technology, and in particular to a cyano-containing polythiophene conductive polymer, its preparation method, and its application. Background Technology

[0002] Conductive polymers (CPs), as organic polymer materials with conjugated structures, are widely used in various fields such as chemical sensing, biopharmaceuticals, and electrode materials for energy storage devices due to their advantages such as good conductivity, ease of modification, simple preparation process, and low cost. Electrochromic supercapacitors (EC-SCs), which combine electrochromic technology with supercapacitors to form a visual intelligent energy storage device, have become an important player in the new energy storage field and have been extensively studied. The electrode material in EC-SC is the key to determining its performance. CPs play a significant role in EC-SC electrode materials due to their multicolor and low cost. Their excellent mechanical flexibility sets them apart from many other electrode materials such as inorganic and carbon materials, successfully bringing EC-SC into the new ranks of flexible intelligent energy storage devices, with great potential for applications in soft robotics, human-computer interaction, and other fields. However, the limited specific capacitance, low energy density, and low cycle stability of CPs are key issues restricting their development. To solve these problems, various approaches have been proposed, such as introducing modifying groups onto the conjugated polymer backbone, copolymerization, or compounding with other materials. Compared to other methods, the approach of introducing modifying groups on the conjugated backbone is not only simple to prepare, but also can improve the performance of CPs from a molecular perspective by utilizing the inherent properties of the modifying groups, thereby enabling them to be better applied in ES-SC.

[0003] As a classic chemical polymeric substance (CP), polythiophene and its derivatives have become one of the most studied organic materials due to their advantages such as high conductivity, rich colors, good environmental stability, good thermal stability, low cost, high carrier mobility, and simple modification methods. Thiophene[3,2-b]thiophene (TT), as one of the raw materials for synthesizing polythiophene and its derivatives, has been widely used in organic photovoltaics, light-emitting diodes, and other fields due to its rigidity and extended π-conjugated structure. However, thiophene[3,2-b]thiophene has an unstable doped structure and a large optical band gap, exhibiting poor electrochemical activity, which hinders its further development in EC-SC. Summary of the Invention

[0004] The purpose of this invention is to provide a cyano-containing polythiophene conductive polymer, its preparation method and application. The doped structure of the cyano-containing polythiophene conductive polymer is more stable and has a larger optical band gap, thus exhibiting excellent electrochemical activity and can be used in EC-SC.

[0005] To achieve the above-mentioned objectives, the present invention provides the following technical solution:

[0006] This invention provides a cyano-containing polythiophene conductive polymer, the structure of which is shown in Formula I:

[0007] Where n = 2 to 100 and n is a natural number.

[0008] This invention also provides a method for preparing a cyano-containing polythiophene conductive polymer, comprising the following steps:

[0009] (1) 3-bromothiophene[3,2-b]thiophene, 4-cyanobenzonic acid, tetrakis(triphenylphosphine)palladium, alkaline substances, organic solvents and water were mixed and coupled under a protective atmosphere to obtain a conductive polymer precursor.

[0010] (2) In a three-electrode system, the conductive polymer precursor described in step (1) is subjected to constant voltage polymerization in an electrolyte to obtain a cyano-containing polythiophene conductive polymer.

[0011] Preferably, in the preparation method of the cyano-containing polythiophene conductive polymer, in step (1), the alkaline substance is anhydrous sodium carbonate or anhydrous potassium carbonate.

[0012] Preferably, in the preparation method of the cyano-containing polythiophene conductive polymer, in step (1), the organic solvent is tetrahydrofuran or acetonitrile.

[0013] Preferably, in the method for preparing a cyano-containing polythiophene conductive polymer, in step (1), the molar ratio of the 3-bromothiopheno[3,2-b]thiophene, the 4-cyanophenylboronic acid, the tetra(triphenylphosphine)palladium and the alkaline substance is 1-3:1.5-3:0.09-1.5:2.8-5.

[0014] Preferably, in the preparation method of the cyano-containing polythiophene conductive polymer, in step (1), the molar volume ratio of the 3-bromothiopheno[3,2-b]thiophene, the organic solvent and the water is 1-3 mol: 15-18 L: 3-5 L.

[0015] Preferably, in the preparation method of the cyano-containing polythiophene conductive polymer, in step (1), the temperature of the coupling reaction is 80-95°C and the time of the coupling reaction is 10-14h.

[0016] Preferably, in the preparation method of the cyano-containing polythiophene conductive polymer, in step (2), the electrolyte is boron trifluoride ethyl ether.

[0017] Preferably, in the method for preparing a cyano-containing polythiophene conductive polymer, in step (2), the voltage of the constant voltage polymerization is 1 to 1.35V.

[0018] The present invention also provides the application of a cyano-containing polythiophene conductive polymer or a cyano-containing polythiophene conductive polymer prepared by the preparation method of the aforementioned cyano-containing polythiophene conductive polymer in optoelectronic devices.

[0019] As can be seen from the above technical solution, compared with the prior art, the present invention has the following beneficial effects:

[0020] This invention introduces a cyano group with a conjugated benzene ring bridge to improve the performance of the thieno[3,2-b]thiophene backbone: 1) As the main functional group, the cyano group has a strong electron-withdrawing ability. The cyano group mainly reduces the band gap of the polymer by lowering the HOMO energy level, adjusts the aromatic π characteristics, and thus effectively controls the electrochromic properties of the conductive polymer, effectively solving the problem that thieno[3,2-b]thiophene has a large optical band gap and exhibits poor electrochemical activity. 2) Compared with common electron-withdrawing groups, the cyano group is more cost-effective. At the same time, the N atom contains a lone pair of electrons, which can act as a hydrogen bond acceptor to form hydrogen bonds, enhance intramolecular and intermolecular interactions, and effectively promote charge transport. 3) The benzene ring is a coplanar group. Its highly conjugated structure can not only be compatible with the π-electron-rich thiophene[3,2-b]thiophene structure to enhance the conjugation of the main chain, thereby improving the easy clustering of polymers, increasing the conjugation length, reducing steric hindrance, and improving the optical properties of materials, but also act as a "bridge" to stabilize the conjugated structure and enhance electron transfer, making the doped structure of thiophene[3,2-b]thiophene more stable.

[0021] This invention introduces cyano groups with aromatic bridges into the conjugated main chain of polythiophene. By controlling the band gap of thiophene[3,2-b]thiophene, changing the conjugation length and steric hindrance, an electrode material with excellent electrochromic and capacitive properties is prepared, thereby constructing a flexible EC-SC device. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below.

[0023] Figure 1 is the NMR hydrogen spectrum of the conductive polymer precursor obtained in step (1) of Example 1;

[0024] Figure 2 is a schematic diagram of the molecular orbital theory of TT, CN-TT and CNPTT;

[0025] Figure 3 shows the LSV diagram of CNPTT obtained in step (1) of Example 1 in boron trifluoride diethyl ether solution;

[0026] Figure 4 is a doping-dedoping cycle diagram of the cyano-containing polythiophene conductive polymer obtained in Example 1 in the boron trifluoride diethyl ether system;

[0027] Figure 5 shows the UV-Vis spectrum of the cyano-containing polythiophene conductive polymer obtained in Example 1 in acetonitrile-perchloric acid;

[0028] Figure 6 is a time-transmittance curve of the cyano-containing polythiophene conductive polymer obtained in Example 1;

[0029] Figure 7 shows the charge-discharge curves of the cyano-containing polythiophene conductive polymer obtained in Example 1.

[0030] Figure 8 shows the fabrication process of the optoelectronic device obtained in Application Example 1;

[0031] Figure 9 is a schematic diagram of the structure of the optoelectronic device obtained in Application Example 1;

[0032] Figure 10 shows the color change of the optoelectronic device obtained in Application Example 1 under the charging / discharging state;

[0033] Figure 11 shows the constant current charge-discharge curve of the optoelectronic device obtained in Application Example 1;

[0034] Figure 12 shows the ultraviolet-visible spectrum of the optoelectronic device obtained in Application Example 1;

[0035] Figure 13 shows the time-transmittance curve of the optoelectronic device obtained in Application Example 1. Detailed Implementation

[0036] This invention provides a cyano-containing polythiophene conductive polymer, the structure of which is shown in Formula I:

[0037] Where n = 2 to 100 and n is a natural number.

[0038] This invention also provides a method for preparing a cyano-containing polythiophene conductive polymer, comprising the following steps:

[0039] (1) 3-bromothiophene[3,2-b]thiophene, 4-cyanobenzonic acid, tetrakis(triphenylphosphine)palladium, alkaline substances, organic solvents and water were mixed and coupled under a protective atmosphere to obtain a conductive polymer precursor.

[0040] (2) In a three-electrode system, the conductive polymer precursor described in step (1) is subjected to constant voltage polymerization in an electrolyte to obtain a cyano-containing polythiophene conductive polymer.

[0041] In this invention, in step (1), the alkaline substance is preferably anhydrous sodium carbonate or anhydrous potassium carbonate, and more preferably anhydrous sodium carbonate.

[0042] In this invention, in step (1), the organic solvent is preferably tetrahydrofuran or acetonitrile, and more preferably tetrahydrofuran.

[0043] In this invention, in step (1), the preferred method for mixing 3-bromothiophene[3,2-b]thiophene, 4-cyanobenzonic acid, tetra(triphenylphosphine)palladium, an alkaline substance, an organic solvent, and water is as follows: mixing 3-bromothiophene[3,2-b]thiophene, 4-fluorophenylboronic acid, and an organic solvent; mixing the alkaline substance with water; then mixing the two resulting mixtures and adding tetra(triphenylphosphine)palladium.

[0044] In this invention, the process of adding tetra(triphenylphosphine)palladium preferably includes: introducing a protective atmosphere for deoxidation; the protective atmosphere is preferably nitrogen.

[0045] In this invention, the deoxygenation conditions are not limited and can be adjusted as needed.

[0046] In this invention, after adding tetra(triphenylphosphine)palladium, it is preferable to further include: introducing a protective atmosphere to replace the original atmosphere.

[0047] In this invention, the conditions for the substitution are not limited and can be adjusted according to requirements.

[0048] In this invention, in step (1), the molar ratio of the 3-bromothiopheno[3,2-b]thiophene, the 4-cyanobenzonic acid, the tetra(triphenylphosphine)palladium, and the alkaline substance is preferably 1-3:1.5-3:0.09-1.5:2.8-5, more preferably 1-1.5:1.5-2:0.09-1.2:2.8-3.5, and even more preferably 1:1.5:0.099:2.98.

[0049] In this invention, in step (1), the molar volume ratio of the 3-bromothiopheno[3,2-b]thiophene, the organic solvent and the water is preferably 1-3 mol: 15-18 L: 3-5 L, more preferably 1-1.5 mol: 15-16 L: 3-4 L, and even more preferably 1 mol: 15.35 L: 3.07 L.

[0050] In this invention, the protective atmosphere in step (1) is preferably nitrogen.

[0051] In this invention, in step (1), the temperature of the coupling reaction is preferably 80-95°C, more preferably 85-90°C, and even more preferably 85°C; the time of the coupling reaction is preferably 10-14h, more preferably 10-12h, and even more preferably 10h.

[0052] In this invention, after the coupling reaction is completed, a post-processing step is preferably included, which preferably includes the following steps: extraction with ethyl acetate to retain the organic phase; drying the obtained organic phase with anhydrous sodium sulfate and then evaporating the solvent; and column chromatography separation to obtain the conductive polymer precursor.

[0053] In this invention, the conditions for the post-processing are not limited, and any solution known to those skilled in the art can be used.

[0054] In this invention, the structure of the conductive polymer precursor in step (1) is shown in Formula II:

[0055] In this invention, the preferred three-electrode system in step (2) is: ITO glass as the working electrode, platinum wire as the counter electrode, and Ag / AgCl as the reference electrode.

[0056] In this invention, specifically in an embodiment, the preparation method of Ag / AgCl preferably includes the following steps:

[0057] Using a constant voltage film deposition method, a silver wire was used as the working electrode, and a platinum wire was used as the reference and counter electrodes, at a voltage of 6 mol·L⁻¹. -1 In a hydrochloric acid solution, Ag / AgCl was obtained by electrochemical deposition at 1.5V for 100s.

[0058] In this invention, in step (2), the electrolyte is preferably boron trifluoride ether.

[0059] In this invention, in step (2), the voltage of the constant voltage polymerization is preferably 1 to 1.35V, more preferably 1.1 to 1.2V, and even more preferably 1.1V.

[0060] In this invention, the reaction formula for the preparation method of the cyano-containing polythiophene conductive polymer is as follows:

[0061] The present invention also provides the application of a cyano-containing polythiophene conductive polymer or a cyano-containing polythiophene conductive polymer prepared by the preparation method of the aforementioned cyano-containing polythiophene conductive polymer in optoelectronic devices.

[0062] In this invention, the method for fabricating the optoelectronic device preferably includes the following steps:

[0063] Electrochemical polymerization was performed on two ITO-PET sheets to obtain a cyano-containing polythiophene conductive polymer and a poly3,4-ethylenedioxythiophene. The ITO-PET containing the cyano-containing polythiophene conductive polymer was used as the working electrode, and the ITO-PET containing the poly3,4-ethylenedioxythiophene was used as the counter electrode. A gel electrolyte was coated on the cyano-containing polythiophene conductive polymer. After the two ITO-PET electrodes were bonded together, they were sealed with vulcanized silicone rubber to obtain an optical device, namely an electrochromic supercapacitor.

[0064] In this invention, the preferred conditions for obtaining the cyano-containing polythiophene conductive polymer by electrochemical polymerization are as follows: in a three-electrode system, ITO glass is used as the working electrode, platinum wire is used as the counter electrode, and Ag / AgCl is used as the reference electrode, and the conductive polymer precursor is subjected to constant voltage polymerization in a boron trifluoride diethyl ether electrolyte; the voltage of the constant voltage polymerization is preferably 1 to 1.35V, more preferably 1.1 to 1.2V, and even more preferably 1.1V; the time of the constant voltage polymerization is preferably 60 to 110s, more preferably 80 to 100s, and even more preferably 80s.

[0065] In this invention, the preferred conditions for obtaining poly(3,4-ethylenedioxythiophene) by electrochemical polymerization are as follows: in a three-electrode system, ITO-PET is used as the working electrode, Ag / AgCl is used as the counter electrode, and platinum wire is used as the reference electrode. 3,4-ethylenedioxythiophene is polymerized at a constant voltage in a boron trifluoride diethyl ether electrolyte. The voltage for the constant voltage polymerization is preferably 0.9–1.1 V, more preferably 1–1.1 V, and even more preferably 1 V. The time for the constant voltage polymerization is preferably 60–110 s, more preferably 90–100 s, and even more preferably 100 s.

[0066] In this invention, specifically in an embodiment, the method for preparing the gel electrolyte preferably includes the following steps:

[0067] Using lithium perchlorate, acetonitrile, polymethyl methacrylate and propylene carbonate in a mass ratio of 3.5:5.5:5.5:85.5 as raw materials, a gel electrolyte was obtained by reacting at 70°C for 6 hours under nitrogen protection.

[0068] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0069] Example 1

[0070] This embodiment provides a method for preparing a cyano-containing polythiophene conductive polymer, including the following steps:

[0071] (1) 4.56 mmol of 3-bromothiophene[3,2-b]thiophene and 6.84 mmol of 4-fluorophenylboronic acid were added to a two-necked flask and mixed with 70 mL of tetrahydrofuran; 13.6 mmol of anhydrous sodium carbonate was dissolved in 14 mL of water and added to the mixture; nitrogen gas was purged into the reaction vessel for 10 min to remove oxygen, and then 0.45 mmol of tetra(triphenylphosphine)palladium was added. The original atmosphere was replaced by nitrogen gas three times, and the system was heated to 85 °C and reacted for 10 h; the organic phase was extracted three times with 20 mL of ethyl acetate and the organic phase was retained; the organic phase was dried with anhydrous sodium sulfate and the solvent was evaporated by rotary evaporator; the white conductive polymer precursor (CNPTT) was obtained by column chromatography with petroleum ether.

[0072] (2) Using the constant voltage film formation method, at 6 mol·L -1 In a hydrochloric acid solution, electrochemical deposition was performed at 1.5V for 100s to obtain a self-made Ag / AgCl.

[0073] Using ITO glass as the working electrode, platinum wire as the counter electrode, and a self-made Ag / AgCl as the reference electrode, the conductive polymer precursor from step (1) was subjected to constant voltage polymerization in a boron trifluoride ether solution in a three-electrode system. The polymerization voltage was 1.1V, resulting in a cyano-containing polythiophene conductive polymer.

[0074] The NMR spectrum of the conductive polymer precursor obtained in step (1) of Example 1 is shown in Figure 1. The results in Figure 1 show that a characteristic peak of the benzene ring appears at around 8 ppm, indicating that the phenyl cyano group has been successfully attached to the thiophene ring.

[0075] This invention uses density functional theory to calculate the band gaps of three molecules: TT, CN-TT, and CNPTT, and plots their molecular orbital theoretical diagrams, as shown in Figure 2. The results in Figure 2 show that the band gap of the CNPTT molecule is 0.81 eV smaller than that of TT, confirming that the cyano-containing polythiophene conductive polymer prepared in this invention can reduce the molecular band gap, providing theoretical support for improving the performance of subsequent polymer materials and their applications.

[0076] Figure 3 shows the LSV (Laser-to-Volume Spectrum) of CNPTT obtained in step (1) of Example 1 in boron trifluoride diethyl ether solution, which was tested using linear sweep voltammetry. The concentration of CNPTT in the solution was 0.01 mol·L⁻¹. -1 The scan rate is 100 mV·s -1 As shown in Figure 3, the initial oxidation potential of CNPTT is 0.85V.

[0077] At a scan rate of 100 mV·s -1The redox stability of the cyano-containing polythiophene conductive polymer obtained in Example 1 in the boron trifluoride diethyl ether system was tested, and the results are shown in Figure 4. The results in Figure 4 show that the thin film of this conductive polymer exhibits excellent electrochemical stability during doping-dedoping cycles, with an electroactivity loss of less than 5% even after 6000 cycles.

[0078] Figure 5 shows the results of using acetonitrile-lithium perchlorate without monomer (the concentration of lithium perchlorate in acetonitrile is 0.1 mol·L⁻¹). -1 The UV-Vis spectrum of the cyano-containing polythiophene conductive polymer obtained in Example 1 is shown in Figure 5. The results indicate that the maximum absorption peaks of the obtained conductive polymer are approximately 460 nm and 1050 nm, respectively. At 0.7 V, the conductive polymer is orange-red; when the applied voltage increases to 1 V, the color of the conductive polymer changes from orange-red to blue. At this point, the absorption peak at 460 nm weakens and eventually disappears, while a new absorption peak appears at 640 nm due to the formation of monopoles and bipolarons.

[0079] Figure 6 shows the time-transmittance curves of the cyano-containing polythiophene conductive polymer obtained in Example 1, measured using a two-step energy dispersive spectroscopy chronoamperometry method at different wavelengths, with a switching time of 10 s. The results in Figure 6 show that the conductive polymer has an optical contrast ratio of 43% at 460 nm and 34% at 1050 nm.

[0080] Figure 7 shows the conductive polymer containing cyano-polythiophene obtained in Example 1 at 1 A·g. -1 2A·g -1 5A·g -1 8A·g -1 10A·g -1 The charging and discharging curves at a current density of 1 A·g are shown in Figure 7. The results indicate that at a current density of 1 A·g -1 At that time, the specific capacitance of the conductive polymer was 232 F·g. -1 When the current density increases to 10 A·g -1 At that time, the specific capacitance of the conductive polymer can still be maintained at 190 F·g. -1 It has excellent rate performance.

[0081] Application Example 1

[0082] This application example provides a method for fabricating an optoelectronic device, including the following steps:

[0083] Using lithium perchlorate, acetonitrile, polymethyl methacrylate and propylene carbonate in a mass ratio of 3.5:5.5:5.5:85.5 as raw materials, the mixture was reacted at 70°C for 6 hours under nitrogen protection to obtain a gel electrolyte.

[0084] A rectangle was made on each of two ITO-PET sheets using double-sided tape for the electrochemical polymerization of monomers. The conductive polymer precursor (CNPTT) obtained in step (1) of Example 1 was electrochemically polymerized on one of the ITO-PET sheets to obtain a cyano-containing polythiophene conductive polymer film (the conditions for electrochemical polymerization were: in a three-electrode system, ITO glass was used as the working electrode, platinum wire as the counter electrode, and Ag / AgCl as the reference electrode; the conductive polymer precursor was polymerized at a constant voltage in a boron trifluoride ether electrolyte at a voltage of 1.1V for 80s); and electrochemical polymerization was carried out on the other ITO-PET sheet to obtain a poly(3,4-ethylenedioxythiophene) (the conditions for electrochemical polymerization were: in a three-electrode system, ITO-PET was used as the working electrode, Ag / AgCl as the counter electrode, and platinum wire as the reference electrode; the 3,4-ethylenedioxythiophene was polymerized at a constant voltage in a boron trifluoride ether electrolyte at a voltage of 1V for 100s).

[0085] Using ITO-PET containing cyano-polythiophene conductive polymer as the working electrode and ITO-PET containing poly3,4-ethylenedioxythiophene as the counter electrode, a gel electrolyte is coated on the surface of the cyano-polythiophene conductive polymer, which serves as an ion-conducting layer. After bonding the two ITO-PET electrodes, they are sealed with vulcanized silicone rubber to obtain an optical device, namely a flexible electrochromic supercapacitor. The fabrication process is shown in Figure 8, and the structural schematic diagram of the flexible electrochromic supercapacitor is shown in Figure 9.

[0086] Figure 10 shows the color change of the flexible electrochromic supercapacitor device obtained in Application Example 1 during charging and discharging. As shown in Figure 10, the device changes from blue-green to orange-red during charging and from orange-red to blue-green during discharging.

[0087] Figure 11 shows the flexible electrochromic supercapacitor device obtained in Application Example 1 at 1 A·g -1 2A·g -1 ,4A·g -1 6A·g -1 The constant current charge-discharge curves at a current density of 1 A·g are shown in Figure 11. -1 At that time, the specific capacitance of the device was 12.8 F·g. -1 When the current density increases to 6 A·g -1 At that time, the specific capacitance of the device can still be maintained at 9 F·g -1 It has excellent rate performance.

[0088] Figure 12 shows the UV-Vis spectrum of the flexible electrochromic supercapacitor device obtained in Application Example 1 from 0.5V to 1.4V. The results in Figure 12 indicate that the maximum absorption peaks of the device are around 480nm and 625nm, respectively.

[0089] Figure 13 shows the time-transmittance curve of the flexible electrochromic supercapacitor device obtained in Application Example 1, tested in a UV-Vis spectrophotometer coupled with an electrochemical workstation. The results in Figure 13 show that the flexible device has an optical contrast of 7% at 480 nm and an optical contrast of 11% at 1050 nm.

[0090] Example 2

[0091] This embodiment provides a method for preparing a cyano-containing polythiophene conductive polymer, including the following steps:

[0092] (1) 6.84 mmol of 3-bromothiophene[3,2-b]thiophene and 10.26 mmol of 4-fluorophenylboronic acid were added to a two-necked flask and mixed with 95 mL of tetrahydrofuran; 20.52 mmol of anhydrous sodium carbonate was dissolved in 25 mL of water and added to the mixture; nitrogen gas was purged into the reaction vessel for 15 min to remove oxygen, and then 0.65 mmol of tetra(triphenylphosphine)palladium was added. The original atmosphere was replaced by nitrogen gas four times, and the system was heated to 88 °C and reacted for 11 h; the organic phase was extracted three times with 30 mL of ethyl acetate and the organic phase was retained; the organic phase was dried with anhydrous sodium sulfate and the solvent was evaporated by rotary evaporator; the white conductive polymer precursor (CNPTT) was obtained by column chromatography with petroleum ether.

[0093] (2) Using the constant voltage film formation method, at 6 mol·L -1 In a hydrochloric acid solution, electrochemical deposition was performed at 1.5V for 100s to obtain a self-made Ag / AgCl.

[0094] Using ITO glass as the working electrode, platinum wire as the counter electrode, and a self-made Ag / AgCl as the reference electrode, the conductive polymer precursor from step (1) was subjected to constant voltage polymerization in a boron trifluoride ether solution in a three-electrode system. The polymerization voltage was 1.2V, resulting in a cyano-containing polythiophene conductive polymer.

[0095] Example 3

[0096] This embodiment provides a method for preparing a cyano-containing polythiophene conductive polymer, including the following steps:

[0097] (1) 7.75 mmol of 3-bromothiopheno[3,2-b]thiophene and 11.62 mmol of 4-fluorophenylboronic acid were added to a two-necked flask and mixed with 116 mL of tetrahydrofuran; 23.10 mmol of anhydrous sodium carbonate was dissolved in 23.79 mL of water and added to the mixture; nitrogen gas was purged into the reaction vessel for 15 min to remove oxygen, and then 0.76 mmol of tetra(triphenylphosphine)palladium was added. The original atmosphere was replaced by nitrogen gas three times, and the system was heated to 90 °C and reacted for 12 h; the organic phase was extracted three times with 35 mL of ethyl acetate and the organic phase was retained; the organic phase was dried with anhydrous sodium sulfate and the solvent was evaporated by rotary evaporator; the white conductive polymer precursor (CNPTT) was obtained by column chromatography with petroleum ether.

[0098] (2) Using the constant voltage film formation method, at 6 mol·L -1 In a hydrochloric acid solution, electrochemical deposition was performed at 1.5V for 100s to obtain a self-made Ag / AgCl.

[0099] Using ITO glass as the working electrode, platinum wire as the counter electrode, and a self-made Ag / AgCl as the reference electrode, the conductive polymer precursor from step (1) was subjected to constant voltage polymerization in a boron trifluoride ether solution in a three-electrode system. The polymerization voltage was 1.35V, resulting in a cyano-containing polythiophene conductive polymer.

[0100] In summary, the cyano-containing polythiophene conductive polymer prepared by this invention, used in electrochromic supercapacitor devices, not only overcomes the bottleneck of the difficulty in polymerizing nitrile materials, but also exhibits excellent electrochemical energy storage and photoelectric properties. Its preparation method is simple and controllable, promoting the rapid processing and preparation of conductive polymer electrode materials and their energy storage applications.

[0101] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A cyano-containing polythiophene conductive polymer, characterized in that, The structure of the cyano-containing polythiophene conductive polymer is shown in Formula I: Where n = 2 to 100 and n is a natural number.

2. The method for preparing a cyano-containing polythiophene conductive polymer according to claim 1, characterized in that, Includes the following steps: (1) 3-bromothiophene[3,2-b]thiophene, 4-cyanobenzonic acid, tetrakis(triphenylphosphine)palladium, alkaline substances, organic solvents and water were mixed and coupled under a protective atmosphere to obtain a conductive polymer precursor. (2) In a three-electrode system, the conductive polymer precursor described in step (1) is subjected to constant voltage polymerization in an electrolyte to obtain a cyano-containing polythiophene conductive polymer.

3. The method for preparing a cyano-containing polythiophene conductive polymer as described in claim 2, characterized in that, In step (1), the alkaline substance is anhydrous sodium carbonate or anhydrous potassium carbonate.

4. The method for preparing a cyano-containing polythiophene conductive polymer as described in claim 3, characterized in that, In step (1), the organic solvent is tetrahydrofuran or acetonitrile.

5. A method for preparing a cyano-containing polythiophene conductive polymer as described in any one of claims 2 to 4, characterized in that, In step (1), the molar ratio of the 3-bromothiopheno[3,2-b]thiophene, the 4-cyanobenzonic acid, the tetra(triphenylphosphine)palladium and the alkaline substance is 1-3:1.5-3:0.09-1.5:2.8-5.

6. The method for preparing a cyano-containing polythiophene conductive polymer as described in claim 5, characterized in that, In step (1), the molar volume ratio of the 3-bromothiopheno[3,2-b]thiophene, the organic solvent, and the water is 1-3 mol: 15-18 L: 3-5 L.

7. A method for preparing a cyano-containing polythiophene conductive polymer as described in claim 2 or 6, characterized in that, In step (1), the temperature of the coupling reaction is 80-95°C and the time of the coupling reaction is 10-14h.

8. The method for preparing a cyano-containing polythiophene conductive polymer as described in claim 2, characterized in that, In step (2), the electrolyte is boron trifluoride ether.

9. The method for preparing a cyano-containing polythiophene conductive polymer as described in claim 8, characterized in that, In step (2), the voltage of the constant voltage polymerization is 1 to 1.35V.

10. The application of the cyano-containing polythiophene conductive polymer according to claim 1 or the cyano-containing polythiophene conductive polymer prepared by any one of claims 2 to 9 in optoelectronic devices.

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