3, 4-ethylene oxythiophene derivative polymer electrochromic material as well as preparation method and application thereof

Abstract

The invention discloses a 3, 4-ethylene oxythiophene derivative polymer electrochromic material and a preparation method and application thereof.An intermediate monomer 3, 4-ethylene oxythiophene derivative is prepared through Suzuki coupling, then the intermediate monomer 3, 4-ethylene oxythiophene derivative is added into an organic solvent containing electrolyte, and a 3, 4-ethylene oxythiophene homopolymer is obtained through electrochemical oxidation polymerization on a conductive substrate. And under the same condition, adding an electroactive monomer as a comonomer, and carrying out electrochemical oxidation copolymerization to obtain the 3, 4-ethylene oxythiophene copolymer. The preparation process is simple, the reaction conditions are mild, the specific capacitance of the prepared copolymer material is up to 2.85 mF cm <-2 >, and the homopolymer is light yellow through a constant potential polarization test; the copolymer is rose red in a normal state and sequentially turns yellow, green and cyan blue under different potentials. The copolymer is used in the fields of intelligent windows, automobile sunroofs, electronic display and the like, and can improve the lighting condition in the space, save energy and reduce consumption.

Description

Technical Field

[0001] This invention belongs to the field of electrochromic electrode material preparation, specifically relating to 3,4-ethyleneoxythiophene-based polymer electrochromic electrode materials, their preparation methods, and applications. Background Technology

[0002] With the continuous growth of the population, people are beginning to focus on how to improve or replace current energy storage methods. The development and utilization of some renewable energy sources (wind energy, tidal energy, geothermal energy, solar energy, etc.) have become hot topics in the energy field. Because the generation of these energy sources has certain regional and temporal characteristics, the utilization of these renewable energy sources requires storage through energy storage devices. This means that the research on energy storage devices must meet the requirement of storing a large amount of energy within a certain period of time and releasing the energy when needed. New energy storage devices such as lithium batteries, fuel cells, and supercapacitors have become the preferred choice for storing this energy. Among them, supercapacitors, due to their high power density, high-current rapid charging and discharging, and long cycle life, have attracted the interest of researchers in the field of energy storage as an emerging energy storage device. Currently, the electrode materials used for supercapacitors include the following: conductive polymers, metal oxides (hydroxides), electroactive small organic molecules, and carbon materials. In recent years, researchers have increasingly focused on the functionalization of energy storage materials. Conductive polymers, since their energy storage and electrochromic properties were discovered, have attracted considerable attention. Conductive polymers such as polypyrrole, polyaniline, and polythiophene have demonstrated impressive energy storage capabilities in electrode research; however, their electron transport remains slow, and intramolecular charge transport is weak, resulting in less than optimal performance as electrochromic materials. Currently, researchers primarily focus on addressing the cycle life issue. Solving the electrochromic stability problem generally involves cross-linking to stabilize the polymer structure. This is because linear polymers undergo structural contraction and expansion during charge and discharge, leading to chain instability and consequently, low cycle life. Shao et al. significantly improved the cycle life of thin-film devices by synthesizing high-performance polyoxytitanate-tris(dithiophene)triphenylamine for polymer cross-linking (Shao M., Ji D., Xu Z., et al. Journal of Power Sources, 2023, 581, 233490). Meanwhile, reducing the color-changing voltage is also an important method to ensure polymer stability. A lower voltage means that covalent bonds will only be subjected to lower energy, thus reducing the degree of breakage. Shao et al. synthesized two novel polymer monomers for polymerization, and these two polymers have low color-changing voltages. The devices assembled from them also exhibit considerable stability (Shao M., Dong J., Lv X., et al. Electrochimica Acta, 2023, 466, 143071). By changing the polymer chain structure, different conjugated structures can be generated in the polymer. When the transition potential required for these conjugated structures is low, the voltage can be reduced.Poly(3,4-ethyleneoxythiophene) is a high-performance conductive polymer that has the advantages of high energy storage and low electrochromic potential. However, it has the same problems as linear polymers. Therefore, it is of practical significance and value to synthesize a polymer with good stability and low electrochromic potential by copolymerizing it with new derivatives. Summary of the Invention

[0003] To address the issues of poor electrochromic ability and low cycle life of traditional conductive polymers, this invention aims to provide a 3,4-vinyloxythiophene-based polymer electrochromic electrode material, its preparation method, and its applications. Method 1: 3,4-vinyloxythiophene-based biopolymer is added to an organic solvent containing an electrolyte, and electrochemical oxidative polymerization is performed to obtain a homopolymer. Method 2: A 3,4-vinyloxythiophene-based derivative and an electroactive monomer are added as two comonomers in different proportions to an organic solvent containing an electrolyte, and electrochemical oxidative copolymerization is performed to obtain a 3,4-vinyloxythiophene-based polymer electrochromic electrode material. The homopolymer obtained by Method 1 has large monomer steric hindrance, making it difficult to obtain polymers with high degrees of polymerization, thus exhibiting low capacitance and no electrochromic response. The copolymer of 3,4-ethyleneoxythiophene derivative and electroactive monomer obtained by method 2, due to the introduction of electroactive groups as linear segments and the multifunctional crosslinking of 3,4-ethyleneoxythiophene monomer, not only has a faster redox process, but also can form a network structure, has better film-forming properties, and has superior electrochromic properties and higher specific capacitance.

[0004] The objective of this invention is specifically achieved through the following technical solution. A method for preparing a 3,4-ethyleneoxythiophene-based polymer electrochromic electrode material includes one of the following methods:

[0005] Method (1): Preparation of 3,4-ethyleneoxythiophene polymer: 3,4-ethyleneoxythiophene derivatives were added to an organic solvent containing electrolytes. The 3,4-ethyleneoxythiophene derivatives were used as monomers. Electrochemical oxidation polymerization was carried out on a conductive matrix. After washing and drying, 3,4-ethyleneoxythiophene homopolymers were obtained.

[0006] Method (2): Preparation of 3,4-ethyleneoxythiophene-based electrochromic copolymer: 3,4-ethyleneoxythiophene derivative and electroactive monomer were added to an organic solvent containing electrolyte in different proportions as two comonomers. Electrochemical oxidation polymerization was carried out on a conductive matrix. After washing and drying, 3,4-ethyleneoxythiophene-based copolymer was obtained.

[0007] Preferably, in methods (1) and (2), the 3,4-ethyleneoxythiophene derivative is one of 2,5-bis(3-hexylthiophene)-3,4-ethyleneoxythiophene, 2,5-bis(bithiophene)-3,4-ethyleneoxythiophene, 2,5-bis(3-thiophene)-3,4-ethyleneoxythiophene, and 2,5-bis(4-methyl3-thiophene)-3,4-ethyleneoxythiophene.

[0008] More preferably, in methods (1) and (2), the 3,4-ethyleneoxythiophene derivative is 2,5-bis(3-thiophene)-3,4-ethyleneoxythiophene.

[0009] Preferably, in method (2), the added electroactive monomer is one of thiophene and its derivatives, methoxyaniline and its derivatives, halogenated pyrrole and its derivatives, and 3,4-ethyleneoxythiophene.

[0010] More preferably, in method (2), the electroactive monomer is 3,4-ethyleneoxythiophene.

[0011] Preferably, in method (2), the molar ratio of the 3,4-ethyleneoxythiophene derivative to the electroactive monomer is 20:1 to 1:20.

[0012] More preferably, in method (2), the molar ratio of the 3,4-ethyleneoxythiophene derivative to the electroactive monomer is 1:2.

[0013] Preferably, in methods (1) and (2), the total concentration of the monomer is 0.0005-1 mol / L.

[0014] More preferably, in methods (1) and (2), the total concentration of the monomer is 0.001 mol / L.

[0015] Preferably, in methods (1) and (2), the electrolyte concentration is 0.001-5 mol / L.

[0016] More preferably, in methods (1) and (2), the electrolyte concentration is 0.1 mol / L.

[0017] Preferably, in methods (1) and (2), the electrolyte is one of tetrabutylammonium perchlorate, lithium perchlorate, lithium tetrafluoroborate, and tetrabutylammonium hexafluorophosphate.

[0018] More preferably, in methods (1) and (2), the electrolyte is tetrabutylammonium hexafluorophosphate.

[0019] Preferably, in methods (1) and (2), the organic solvent is at least one of methanol, acetonitrile, N,N-dimethylformamide, dimethyl sulfoxide, propylene carbonate, tetrahydrofuran, and dichloromethane.

[0020] Preferably, in methods (1) and (2), the conductive substrate is at least one of glassy carbon, ITO glass, polymer matrix with conductive layer, carbon cloth, carbon paper, Prussian blue, and tungsten trioxide.

[0021] More preferably, in methods (1) and (2), the conductive substrate is ITO glass.

[0022] Preferably, in methods (1) and (2), the sheet resistance of the ITO glass is 10-100Ω.

[0023] More preferably, in methods (1) and (2), the sheet resistance of the ITO glass is 10Ω.

[0024] Preferably, in methods (1) and (2), the number of CV scans for the electrochemical oxidative polymerization reaction is 5-100.

[0025] More preferably, in methods (1) and (2), the number of CV scans for the electrochemical oxidative polymerization reaction is 15.

[0026] Preferably, in methods (1) and (2), the CV scan potential range of the electrochemical oxidative polymerization reaction is -1 to 2V.

[0027] More preferably, in methods (1) and (2), the CV scan potential range of the electrochemical oxidative polymerization reaction is -0.2 to 1.6 V.

[0028] Preferably, in methods (1) and (2), the electrochemical oxidative polymerization is performed using cyclic voltammetry with a scan rate of 20-200 mV s. -1 .

[0029] More preferably, in methods (1) and (2), the scan rate of the electrochemical oxidative polymerization is 100 mV s. -1 .

[0030] Preferably, in methods (1) and (2), the drying environment is a vacuum, the temperature is 20-60℃, and the drying time is 6-48h.

[0031] More preferably, in methods (1) and (2), the drying environment is a vacuum, the temperature is 40°C, and the drying time is 12h.

[0032] The copolymer material prepared by the above-described method has a specific capacitance as high as 2.85 mF cm⁻¹. -2The homopolymer was found to be pale yellow through constant potential polarization testing; the copolymer was magenta at normal temperature (0V), changed color to yellow at 0.5V, green at 0.6V, and cyan at 0.8V. This copolymer can be used in fields such as smart windows, automotive sunroofs, and electronic displays, improving indoor lighting conditions and reducing energy consumption.

[0033] Application of the 3,4-ethyleneoxythiophene-based polymer electrochromic electrode material in electrochromic devices.

[0034] Application of the 3,4-ethyleneoxythiophene-based polymer electrochromic electrode material in energy storage devices.

[0035] Compared with the prior art, the present invention has the following advantages and technical effects:

[0036] (1) The optimal performance of the thiophene-bridged 3,4-ethyleneoxythiophene copolymer synthesized in this invention is 2.85 mF / cm. -2 The areal specific capacitance is a type of energy storage electrode material with high specific capacitance.

[0037] (2) The 3,4-ethyleneoxythiophene-based electrochromic copolymer synthesized in this invention introduces electroactive monomers for copolymerization, which makes the copolymers form network nodes during polymerization. Through multifunctional crosslinking of 3,4-ethyleneoxythiophene monomers, the copolymer chains are uniformly attached to the surface of ITO glass in a network structure, thereby increasing the specific surface area of ​​the composite material and thus increasing the contact area between the electrolyte and the electrode. At the same time, the electroactive monomers, as sites for redox reactions, can provide more pseudocapacitance, and the electroactive monomers can better disperse the charge, which is beneficial to charge transport.

[0038] (3) The present invention uses 3,4-ethyleneoxythiophene derivative and electroactive monomer as two comonomers to prepare an electrochromic device. Experimental results show that the device has the advantages of fast color change response, large transmittance change and good stability.

[0039] (4) The synthesis process of the present invention is simple to operate, the reaction conditions are mild, and the energy consumption is low, making it suitable for large-scale industrial applications. Attached Figure Description

[0040] Figure 1 This is a synthetic route diagram of the 3,4-ethyleneoxythiophene-based polymer electrochromic electrode material of the present invention.

[0041] Figure 2 The polymerization CV diagram is shown for the 3,4-ethyleneoxythiophene homopolymer material prepared in Example 2 of this invention.

[0042] Figure 3The polymerization CV diagram is shown for the 3,4-ethyleneoxythiophene copolymer material obtained in Example 3 of this invention.

[0043] Figure 4 The 3,4-ethyleneoxythiophene copolymer material prepared in Example 3 of this invention was tested at 25, 50, 75, 100, 150, and 200 mV s. -1 The CV diagram.

[0044] Figure 5 The 3,4-ethyleneoxythiophene copolymer material prepared in Example 3 of this invention was subjected to various molecular weight ratios (0.05, 0.1, 0.2, 0.5, 0.7, and 1 mA cm⁻¹. -2 A comparison chart of constant current charging and discharging.

[0045] Figure 6 The electrochromic results of the device assembled from the 3,4-ethyleneoxythiophene-based polymer material prepared in the embodiments of the present invention. Detailed Implementation

[0046] The specific implementation of the present invention will be further described below with reference to examples and accompanying drawings, but the embodiments of the present invention are not limited thereto.

[0047] Figure 1 This is a synthetic route diagram for the 3,4-ethyleneoxythiophene-based polymer electrochromic electrode material proposed in this invention. The following examples follow... Figure 1 The process is shown below. Refer to... Figure 1 The present invention provides synthetic routes for preparing 3,4-ethyleneoxythiophene-based homopolymer materials and 3,4-ethyleneoxythiophene-based copolymer materials. The synthesis method of the 3,4-ethyleneoxythiophene-based homopolymer material is as follows: an intermediate 3,4-ethyleneoxythiophene derivative is prepared via Suzuki coupling, and then added to an organic solvent containing an electrolyte, followed by electrochemical oxidative polymerization to obtain the homopolymer. The 3,4-ethyleneoxythiophene-based copolymer material is prepared via Suzuki coupling, and then added to an organic solvent containing an electrolyte in different proportions along with an electroactive monomer, followed by electrochemical oxidative copolymerization to obtain a 3,4-ethyleneoxythiophene-based polymer electrochromic electrode material.

[0048] Example 1

[0049] (1) Preparation of 3,4-ethyleneoxythiophene homopolymer: 2,5-bis(3-hexylthiophene)-3,4-ethyleneoxythiophene and tetrabutylammonium hexafluorophosphate were added to 30 ml of dichloromethane. The initial concentration of tetrabutylammonium hexafluorophosphate was 0.001 mol / L, and the initial concentration of 2,5-bis(3-hexylthiophene)-3,4-ethyleneoxythiophene was 0.5 mmol / L. Electrochemical oxidation polymerization was then carried out using a platinum column electrode as the counter electrode, ITO glass as the working electrode, and an Ag / AgCl electrode as the reference electrode via cyclic voltammetry at a scan rate of 20 mV s. -1 The number of cycles was 30, and the potential range was -1 to 1.4V. Finally, the obtained polymer film was washed and dried to obtain a thiophene-bridged 3,4-ethyleneoxythiophene homopolymer material.

[0050] (2) Preparation of 3,4-ethyleneoxythiophene copolymer material: 2,5-bis(3-thiophene)-3,4-ethyleneoxythiophene, chloropyrrole, and tetrabutylammonium hexafluorophosphate were added to 30 ml of dichloromethane. The initial electrolyte concentration was 0.001 mol / L, the initial total monomer concentration was 0.5 mmol / L, and the molar ratio of the two monomers was 1:1. Electrochemical oxidation polymerization was then carried out using a platinum column electrode as the counter electrode, ITO glass as the working electrode, and an Ag / AgCl electrode as the reference electrode via cyclic voltammetry. The cycle number was 50, and the scan rate was 20 mV / s. -1 The potential range is -1 to 1.6V. Finally, the obtained polymer film is washed and dried to obtain a 3,4-ethyleneoxythiophene copolymer material.

[0051] Example 2

[0052] (1) Preparation of 3,4-ethyleneoxythiophene homopolymer: 2,5-bis(3-thiophene)-3,4-ethyleneoxythiophene and tetrabutylammonium hexafluorophosphate were added to 30 ml of dichloromethane. The concentration of tetrabutylammonium hexafluorophosphate was 0.1 mol / L, and the initial concentration of 2,5-bis(3-thiophene)-3,4-ethyleneoxythiophene was 1 mmol / L. Electrochemical oxidation polymerization was then carried out using a platinum column electrode as the counter electrode, ITO glass as the working electrode, and an Ag / AgCl electrode as the reference electrode via cyclic voltammetry. The cycle number was 15, and the scan rate was 100 mV s. -1 The potential range is 0–1.6 V. Finally, the obtained polymer film is washed and dried to obtain a 3,4-ethyleneoxythiophene homopolymer material.

[0053] like Figure 2As shown, the first CV curve showed a clear redox peak at around 1.2V, but the polymerization reaction could not occur by cycling only at 1.2V. Subsequently, the current increased above 1.5V, and a new oxidation peak appeared. Furthermore, as the number of scan cycles increased, the area around the original curve continuously increased, proving that the monomers underwent a polymerization reaction within this potential range, indicating that the polymer was successfully prepared.

[0054] (2) Preparation of 3,4-ethyleneoxythiophene copolymer material: 2,5-bis(3-thiophene)-3,4-ethyleneoxythiophene, methoxyaniline, and tetrabutylammonium perchlorate were added to 30 ml of dichloromethane. The concentration of tetrabutylammonium perchlorate was 1 mol / L, the initial total concentration of monomers was 0.5 mol / L, and the molar ratio of 2,5-bis(3-thiophene)-3,4-ethyleneoxythiophene to methoxyaniline was 1:10. Electrochemical oxidation polymerization was then carried out using a platinum column electrode as the counter electrode, a glassy carbon electrode as the working electrode, and an Ag / AgCl electrode as the reference electrode via cyclic voltammetry. The number of cycles was 50, and the scan rate was 50 mV / s. -1 The potential range is -1 to 1.6V. Finally, the obtained polymer film is washed and dried to obtain a 3,4-ethyleneoxythiophene copolymer material.

[0055] Example 3

[0056] (1) Preparation of 3,4-ethyleneoxythiophene homopolymer: 2,5-bis(3-thiophene)-3,4-ethyleneoxythiophene and lithium tetrafluoroborate were added to 30 ml of dichloromethane. The concentration of lithium tetrafluoroborate was 5 mol / L, and the initial concentration of 2,5-bis(3-thiophene)-3,4-ethyleneoxythiophene was 1 mol / L. Electrochemical oxidation polymerization was then carried out using a platinum column electrode as the counter electrode, ITO glass as the working electrode, and an Ag / AgCl electrode as the reference electrode via cyclic voltammetry at a scan rate of 50 mV s. -1 The number of cycles was 5, and the potential range was 0–2V. Finally, the obtained polymer film was washed and dried to obtain a 3,4-ethyleneoxythiophene homopolymer material.

[0057] (2) Preparation of 3,4-ethyleneoxythiophene copolymer material: 2,5-bis(3-thiophene)-3,4-ethyleneoxythiophene, 3,4-ethyleneoxythiophene, and tetrabutylammonium hexafluorophosphate were added to 30 ml of dichloromethane. The concentration of tetrabutylammonium hexafluorophosphate was 0.1 mol / L, the initial total concentration of monomers was 1 mmol / L, and the molar ratio of 2,5-bis(3-thiophene)-3,4-ethyleneoxythiophene to 3,4-ethyleneoxythiophene was 1:2. Electrochemical oxidation polymerization was then carried out using a platinum column electrode as the counter electrode, ITO glass as the working electrode, and an Ag / AgCl electrode as the reference electrode via cyclic voltammetry. The number of cycles was 15, and the scan rate was 100 mV s. -1 The potential range is -0.2 to 1.6 V. Finally, the obtained polymer film is washed and dried to obtain a 3,4-ethyleneoxythiophene copolymer material. The obtained material was tested at 0.05 mA cm⁻¹. -2 At a current density, the specific capacitance can reach 2.85 mF / cm. -2 .

[0058] like Figure 3 As shown, the first CV curve also showed a clear redox peak at around 1.2V. However, the polymerization reaction could not occur by cycling only at 1.2V. Subsequently, the current increased above 1.5V, and a new oxidation peak appeared. Furthermore, as the number of scan cycles increased, a new reduction peak different from that of the homopolymer monomer appeared. Afterward, the two different reduction peaks merged, and the area around the original curve continued to increase with the number of scan cycles, proving that the two monomers had undergone a polymerization reaction within this potential range, indicating that the copolymer was successfully prepared.

[0059] The CV curve of the 3,4-ethyleneoxythiophene copolymer material prepared in this embodiment was tested to analyze its response to different scan rates. Figure 4 As shown in the figure, at 25mV s -1 At a scan rate of 0.4V, a significant oxidation peak appears near 0.4V. During the reverse scan, a reduction peak is obvious. Moreover, as the scan rate gradually increases, the oxidation and reduction peaks become more and more obvious, proving that the material responds quickly to changes in scan rate.

[0060] The 3,4-ethyleneoxythiophene-based polymer material prepared in this embodiment was subjected to constant current charge-discharge testing. Figure 5 As shown, the potential window is 0–1V, and it increases with increasing current density at 0.5 mA cm⁻¹. -2 At a current density, the specific capacitance is still 0.05 mA cm. -2 The current density is 70.5%, which proves its good rate performance.

[0061] The 3,4-ethyleneoxythiophene-based polymer material prepared in this embodiment was used for device assembly and UV-ECG coupled with electrochemical analysis to characterize its electrochromic ability, such as... Figure 6 As shown, it can be observed that the ultraviolet absorption of the electrochromic device changes within the voltage range of -0.4 to 0.8V. The ultraviolet absorption at each potential conforms to the color changes described above, that is, it is magenta at normal (0V), yellow at 0.5V, green at 0.6V, and cyan at 0.8V.

[0062] Example 4

[0063] (1) Preparation of 3,4-ethyleneoxythiophene homopolymer: 2,5-bis(3-thiophene)-3,4-ethyleneoxythiophene and tetrabutylammonium hexafluorophosphate were added to 30 ml of acetonitrile. The concentration of tetrabutylammonium hexafluorophosphate was 1 mol / L, and the initial concentration of 2,5-bis(3-thiophene)-3,4-ethyleneoxythiophene was 1 mmol / L. Electrochemical oxidation polymerization was then carried out using a platinum column electrode as the counter electrode, carbon cloth as the working electrode, and an Ag / AgCl electrode as the reference electrode via cyclic voltammetry. The number of cycles was 100, and the scan rate was 100 mV s. -1 The potential range is 0–1.8V. Finally, the obtained polymer is washed and dried to obtain a 3,4-ethyleneoxythiophene homopolymer material.

[0064] (2) Preparation of 3,4-ethyleneoxythiophene copolymer material: 2,5-bis(3-thiophene)-3,4-ethyleneoxythiophene, 3-hexylthiophene, and tetrabutylammonium hexafluorophosphate were added to 30 ml of dichloromethane. The concentration of tetrabutylammonium hexafluorophosphate was 0.5 mol / L, the initial total concentration of monomers was 0.05 mol / L, and the molar ratio of 2,5-bis(3-thiophene)-3,4-ethyleneoxythiophene to 3-hexylthiophene was 20:1. Electrochemical oxidation polymerization was then carried out using a platinum column electrode as the counter electrode, ITO glass as the working electrode, and an Ag / AgCl electrode as the reference electrode via cyclic voltammetry. The number of cycles was 20, and the scan rate was 200 mV s. -1 The potential range is -1 to 2V. Finally, the obtained polymer film is washed and dried to obtain a 3,4-ethyleneoxythiophene copolymer material.

[0065] Example 5

[0066] (1) Preparation of 3,4-ethyleneoxythiophene homopolymer: 2,5-bis(3-thiophene)-3,4-ethyleneoxythiophene and lithium perchlorate were added to 30 ml of dichloromethane. The concentration of lithium perchlorate was 0.1 mol / L, and the initial concentration of 2,5-bis(3-thiophene)-3,4-ethyleneoxythiophene was 0.005 mol / L. Electrochemical oxidation polymerization was then carried out using a platinum column electrode as the counter electrode, ITO glass as the working electrode, and an Ag / AgCl electrode as the reference electrode via cyclic voltammetry. The cycle number was 100, and the scan rate was 200 mV s. -1 The potential range is 0–1.4 V. Finally, the obtained polymer film is washed and dried to obtain a 3,4-ethyleneoxythiophene homopolymer material.

[0067] (2) Preparation of 3,4-ethyleneoxythiophene copolymer material: 2,5-bis(3-thiophene)-3,4-ethyleneoxythiophene, 3,4-ethyleneoxythiophene, and tetrabutylammonium hexafluorophosphate were added to 30 ml of dichloromethane. The concentration of tetrabutylammonium hexafluorophosphate was 0.1 mol / L, the initial total concentration of monomers was 1 mmol / L, and the molar ratio of 2,5-bis(3-thiophene)-3,4-ethyleneoxythiophene to 3,4-ethyleneoxythiophene was 3:1. Electrochemical oxidation polymerization was then carried out using a platinum column electrode as the counter electrode, ITO glass as the working electrode, and an Ag / AgCl electrode as the reference electrode via cyclic voltammetry. The number of cycles was 40, and the scan rate was 100 mV s. -1 The potential range is 0–1.5V. Finally, the obtained polymer film is washed and dried to obtain a 3,4-ethyleneoxythiophene copolymer material.

[0068] Example 6

[0069] (1) Preparation of 3,4-ethyleneoxythiophene homopolymer: 2,5-bis(3-thiophene)-3,4-ethyleneoxythiophene and tetrabutylammonium hexafluorophosphate were added to 30 ml of dichloromethane. The concentration of tetrabutylammonium hexafluorophosphate was 0.1 mol / L, and the initial concentration of 2,5-bis(3-thiophene)-3,4-ethyleneoxythiophene was 0.05 mol / L. Electrochemical oxidation polymerization was then carried out using a platinum column electrode as the counter electrode, ITO glass as the working electrode, and an Ag / AgCl electrode as the reference electrode via cyclic voltammetry. The number of cycles was 20, and the scan rate was 100 mV s. -1 The potential range is -0.6 to 1.5 V. Finally, the obtained polymer film is washed and dried to obtain a 3,4-ethyleneoxythiophene homopolymer material.

[0070] (2) Preparation of 3,4-ethyleneoxythiophene copolymer material: 2,5-bis(3-thiophene)-3,4-ethyleneoxythiophene, 3,4-ethyleneoxythiophene, and tetrabutylammonium hexafluorophosphate were added to 30 ml of dichloromethane. The concentration of tetrabutylammonium hexafluorophosphate was 0.1 mol / L, the initial total concentration of monomers was 0.1 mol / L, and the molar ratio of 2,5-bis(3-thiophene)-3,4-ethyleneoxythiophene to 3,4-ethyleneoxythiophene was 3:1. Electrochemical oxidation polymerization was then carried out using a platinum column electrode as the counter electrode, ITO glass as the working electrode, and an Ag / AgCl electrode as the reference electrode via cyclic voltammetry. The number of cycles was 40, and the scan rate was 100 mV / s. -1 The potential range is 0–1.5V. Finally, the obtained polymer film is washed and dried to obtain a 3,4-ethyleneoxythiophene copolymer material.

[0071] Example 7

[0072] (1) Preparation of 3,4-ethyleneoxythiophene homopolymer: 2,5-bis(3-thiophene)-3,4-ethyleneoxythiophene and tetrabutylammonium hexafluorophosphate were added to 30 ml of tetrahydrofuran. The concentration of tetrabutylammonium hexafluorophosphate was 0.1 mol / L, and the initial concentration of 2,5-bis(3-thiophene)-3,4-ethyleneoxythiophene was 0.005 mol / L. Electrochemical oxidation polymerization was then carried out using a platinum column electrode as the counter electrode, ITO glass as the working electrode, and an Ag / AgCl electrode as the reference electrode via cyclic voltammetry. The number of cycles was 100, and the scan rate was 100 mV s. -1 The potential range is -0.3 to 1.8 V. Finally, the obtained polymer film is washed and dried to obtain a 3,4-ethyleneoxythiophene homopolymer material.

[0073] (2) Preparation of 3,4-ethyleneoxythiophene copolymer material: 2,5-bis(3-thiophene)-3,4-ethyleneoxythiophene, 3,4-ethyleneoxythiophene, and tetrabutylammonium hexafluorophosphate were added to 30 ml of dichloromethane. The concentration of tetrabutylammonium hexafluorophosphate was 0.1 mol / L, the initial total concentration of monomers was 1 mol / L, and the molar ratio of 2,5-bis(3-thiophene)-3,4-ethyleneoxythiophene to 3,4-ethyleneoxythiophene was 1:20. Electrochemical oxidation polymerization was then carried out using a platinum column electrode as the counter electrode, ITO glass as the working electrode, and an Ag / AgCl electrode as the reference electrode via cyclic voltammetry. The number of cycles was 5, and the scan rate was 200 mV s. -1 The potential range is 0–1.4V. Finally, the obtained polymer film is washed and dried to obtain a 3,4-ethyleneoxythiophene copolymer material.

[0074] Example 8

[0075] (1) Preparation of 3,4-ethyleneoxythiophene homopolymer: 2,5-bis(3-thiophene)-3,4-ethyleneoxythiophene and tetrabutylammonium hexafluorophosphate were added to 30 ml of methanol. The concentration of tetrabutylammonium hexafluorophosphate was 1 mol / L, and the initial concentration of 2,5-bis(3-thiophene)-3,4-ethyleneoxythiophene was 0.1 mol / L. Electrochemical oxidation polymerization was then carried out using a platinum column electrode as the counter electrode, ITO glass as the working electrode, and an Ag / AgCl electrode as the reference electrode via cyclic voltammetry. The number of cycles was 15, and the scan rate was 150 mV s. -1 The potential range is -0.3 to 1.8 V. Finally, the obtained polymer film is washed and dried to obtain a 3,4-ethyleneoxythiophene homopolymer material.

[0076] (2) Preparation of 3,4-ethyleneoxythiophene copolymer material: 2,5-bis(3-thiophene)-3,4-ethyleneoxythiophene, 3,4-ethyleneoxythiophene, and tetrabutylammonium hexafluorophosphate were added to 30 ml of dichloromethane. The concentration of tetrabutylammonium hexafluorophosphate was 0.1 mol / L, the initial total concentration of monomers was 0.0005 mol / L, and the molar ratio of 2,5-bis(3-thiophene)-3,4-ethyleneoxythiophene to 3,4-ethyleneoxythiophene was 9:1. Electrochemical oxidation polymerization was then carried out using a platinum column electrode as the counter electrode, carbon paper as the working electrode, and an Ag / AgCl electrode as the reference electrode via cyclic voltammetry. The number of cycles was 100, and the potential range was -0.3 to 1.7 V. Finally, the obtained polymer film was washed and dried to obtain the 3,4-ethyleneoxythiophene copolymer material.

[0077] Example 9

[0078] (1) Preparation of 3,4-ethyleneoxythiophene homopolymer: 2,5-bis(3-thiophene)-3,4-ethyleneoxythiophene and tetrabutylammonium hexafluorophosphate were added to 30 ml of methanol. The concentration of tetrabutylammonium hexafluorophosphate was 1 mol / L, and the initial concentration of 2,5-bis(3-thiophene)-3,4-ethyleneoxythiophene was 0.1 mol / L. Electrochemical oxidation polymerization was then carried out using a platinum column electrode as the counter electrode, ITO glass as the working electrode, and an Ag / AgCl electrode as the reference electrode via cyclic voltammetry. The number of cycles was 15, and the scan rate was 150 mV s. -1 The potential range is -0.3 to 1.8 V. Finally, the obtained polymer film is washed and dried to obtain a 3,4-ethyleneoxythiophene homopolymer material.

[0079] (2) Preparation of 3,4-ethyleneoxythiophene copolymer material: 2,5-di(4-methyl3-thiophene)-3,4-ethyleneoxythiophene, 3,4-ethyleneoxythiophene, and tetrabutylammonium hexafluorophosphate were added to 30 ml of dichloromethane. The concentration of tetrabutylammonium hexafluorophosphate was 0.1 mol / L, the initial total concentration of monomers was 0.0005 mol / L, and the molar ratio of 2,5-di(3-thiophene)-3,4-ethyleneoxythiophene to 3,4-ethyleneoxythiophene was 2:1. Electrochemical oxidation polymerization was then carried out using a platinum column electrode as the counter electrode, carbon paper as the working electrode, and an Ag / AgCl electrode as the reference electrode via cyclic voltammetry. The number of cycles was 50, and the potential range was -0.4 to 1.7 V. Finally, the obtained polymer film was washed and dried to obtain the 3,4-ethyleneoxythiophene copolymer material.

Claims

A method for preparing a 1,3,4-ethyleneoxythiophene-based polymer electrochromic electrode material, characterized in that, The 3,4-ethyleneoxythiophene-based polymer electrochromic electrode material includes 3,4-ethyleneoxythiophene-based homopolymer material and 3,4-ethyleneoxythiophene-based copolymer material, and their preparation methods are as follows: (1) Preparation of 3,4-ethyleneoxythiophene polymer: 3,4-ethyleneoxythiophene derivatives were added to an organic solvent containing electrolytes and electrochemically oxidized on a conductive matrix. After washing and drying, 3,4-ethyleneoxythiophene homopolymer was obtained. (2) Preparation of 3,4-ethyleneoxythiophene-based electrochromic copolymer: 3,4-ethyleneoxythiophene derivative and electroactive monomer were added to an organic solvent containing electrolyte in different proportions as two comonomers. After electrochemical oxidation polymerization on a conductive matrix, the copolymer was washed and dried to obtain 3,4-ethyleneoxythiophene-based copolymer.

2. The method for preparing the 3,4-ethyleneoxythiophene-based polymer electrochromic electrode material according to claim 1, characterized in that, In methods (1) and (2), the 3,4-ethyleneoxythiophene derivative is one of 2,5-bis(3-hexylthiophene)-3,4-ethyleneoxythiophene, 2,5-bis(bithiophene)-3,4-ethyleneoxythiophene, 2,5-bis(4-methyl3-thiophene)-3,4-ethyleneoxythiophene, and 2,5-bis(3-thiophene)-3,4-ethyleneoxythiophene. The initial monomer concentration for the electrochemical oxidative polymerization of the 3,4-ethyleneoxythiophene derivative is 0.0005-1 mol / L, and the electrolyte concentration is 0.001-5 mol / L.

3. The method for preparing the 3,4-ethyleneoxythiophene-based polymer electrochromic electrode material according to claim 1, characterized in that, In method (2), the molar ratio of the 3,4-ethyleneoxythiophene derivative to the electroactive monomer is 20:1-1:20; The electroactive monomer is one of thiophene and its derivatives, methoxyaniline and its derivatives, halopyrrole and its derivatives, and 3,4-ethoxythiophene. The initial total monomer concentration for the electrochemical oxidative polymerization of the 3,4-ethyleneoxythiophene derivative with the electroactive monomer is 0.0005-1 mol / L, and the electrolyte concentration is 0.001-5 mol / L.

4. The method for preparing the 3,4-ethyleneoxythiophene-based polymer electrochromic electrode material according to claim 1, characterized in that, In methods (1) and (2), the electrolyte is one of tetrabutylammonium perchlorate, lithium perchlorate, lithium tetrafluoroborate, and tetrabutylammonium hexafluorophosphate. The organic solvent is at least one of methanol, acetonitrile, N,N-dimethylformamide, dimethyl sulfoxide, propylene carbonate, tetrahydrofuran, and dichloromethane.

5. The method for preparing the 3,4-ethyleneoxythiophene-based polymer electrochromic electrode material according to claim 1, characterized in that, In methods (1) and (2), the electrochemical oxidation polymerization method used is cyclic voltammetry, with a potential range of -1 to 2V.

6. The method for preparing the 3,4-ethyleneoxythiophene-based polymer electrochromic electrode material according to claim 1, characterized in that, In methods (1) and (2), the electrochemical oxidative polymerization is performed using cyclic voltammetry with a scan rate of 20-200 mV s. -1 .

7. The method for preparing the 3,4-ethyleneoxythiophene-based polymer electrochromic electrode material according to claim 1, characterized in that, In methods (1) and (2), the conductive substrate is at least one of glassy carbon, ITO glass, polymer matrix with conductive layer, carbon cloth, carbon paper, Prussian blue, and tungsten trioxide.

8. A 3,4-ethyleneoxythiophene-based polymer electrochromic electrode material prepared by the preparation method according to any one of claims 1-7, characterized in that, The 3,4-ethyleneoxythiophene copolymer material has a specific capacitance as high as 2.85 mF cm⁻¹. -2 The 3,4-ethyleneoxythiophene homopolymer material is pale yellow, and the 3,4-ethyleneoxythiophene copolymer material is rose red under normal conditions. When voltage is applied, it changes from rose red to yellow, then to green, and finally to cyan.

9. The application of the 3,4-ethyleneoxythiophene-based polymer electrochromic electrode material according to claim 8 in electrochromic devices.

10. The application of the 3,4-ethyleneoxythiophene-based polymer electrochromic electrode material according to claim 8 in energy storage devices.

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