A multi-stage corrugated polyaniline film with a two-dimensional inverse opal photonic crystal structure and a preparation method thereof
By combining gas-liquid self-assembly and electrochemical in-situ polymerization with mechanical stretching, a multi-level wrinkled polyaniline film with a two-dimensional inverse opal photonic crystal structure was prepared, which solved the problems of complexity and high cost of traditional methods and realized the low-cost and controllable preparation of micro and nano surface structures.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- INST OF BIOLOGICAL & MEDICAL ENG GUANGDONG ACAD OF SCI
- Filing Date
- 2023-09-21
- Publication Date
- 2026-07-03
AI Technical Summary
Existing technologies make it difficult to construct controllable polyaniline micro/nano surface structures, especially two-dimensional ordered wrinkled structures, through simple methods, and traditional methods are complex and costly.
Two-dimensional photonic crystal microspheres were prepared by gas-liquid self-assembly, and then combined with electrochemical in-situ polymerization and mechanical stretching to prepare multi-level wrinkled polyaniline films with a two-dimensional inverse opal photonic crystal structure. The specific steps included self-assembling microspheres on conductive glass, electrochemical polymerization, etching microspheres, transferring them to the PDMS surface and stretching them.
A low-cost and simple preparation method was developed to obtain multi-level wrinkled polyaniline films with regular micro-nano structures, which are suitable for applications such as supercapacitors, flexible electrodes, and sensors.
Smart Images
Figure CN117301663B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of micro / nano structure construction technology on the surface of thin film materials, and in particular to a multi-level wrinkled polyaniline thin film with a two-dimensional inverse opal photonic crystal structure and its preparation method. Background Technology
[0002] Traditional surface micropatterning techniques primarily utilize methods such as laser etching, chemical etching, photolithography, flatbed printing, and imprinting. These methods are mature, stable, and highly reproducible, and have already been industrialized; however, the manufacturing equipment is expensive and the procedures are complex. Developing molecular self-assembly and interface self-organization techniques to construct micropatterns, independent of traditional etching technologies and with dynamically controllable pattern shape, size, and surface properties, is currently a hot research topic internationally. The abundance of stress-induced wrinkled micropatterns found in nature has inspired scientists and engineers to develop simple and low-cost microfabrication techniques. By depositing a hard film on a soft substrate and then applying stress, multi-scale wrinkled patterns can be easily obtained. After decades of development, surface wrinkling has become a simple, efficient, low-cost, and structurally controllable microstructuring method.
[0003] Polyaniline (PANI) is a polymer compound with unique electrical and optical properties. After doping, it can acquire electrical conductivity and electrochemical properties. It is commonly used in devices such as flexible actuators. PANI materials with micro / nano structures have a better specific surface area; therefore, introducing micro / nano-sized wrinkled structures onto the surface of PANI films is expected to exhibit excellent performance in fields such as supercapacitors, flexible electrodes and sensors, and functionalized coatings. Patent CN113929950A utilizes in-situ deposition polymerization to prepare a smooth PANI film on a plastic substrate, and then further grows PANI on the film by alternately immersing it in an oxidant and aniline monomer solution to induce wrinkling, thus preparing wrinkled PANI on the plastic. Patent CN114054320A uses polydimethylsiloxane as a substrate and constructs a PANI film on a PDMS substrate using spin coating technology, then uses alternating introduction of hydrogen chloride gas and ammonia gas to achieve wrinkling or de-wrinkling of the PANI film. This type of method only wrinkles the surface of polyaniline, but there are few reports on methods for preparing two-dimensional ordered polyaniline wrinkles through regularly arranged surface arrays, and then constructing regular micro / nano structures on the surface of the two-dimensional ordered wrinkles to form a multi-level wrinkled structure. For example, patent ZL202111332790.X combines selective oxygen plasma treatment technology and spin coating technology to prepare patterned polyaniline arrays, and uses thermally induced wrinkling to form wrinkled microstructures in the polyaniline array, resulting in a wrinkled polyaniline patterned array. This method combines plasma treatment technology, spin coating technology, and thermal induction method, and the process steps are cumbersome.
[0004] Since there is no suitable structure-directing agent to achieve the assembly of polyaniline monomers, we seek to find a simple way to construct controllable micro- and nano-surface structures for polyaniline by using surface wrinkling methods, which provides a new approach for the patterned construction of polyaniline. Summary of the Invention
[0005] The purpose of this invention is to provide a multi-level wrinkled polyaniline thin film with a two-dimensional inverse opal photonic crystal structure and its preparation method. This invention prepares two-dimensional ordered polyaniline wrinkles by regularly arranged surface arrays, and constructs regular micro-nano structures on the surface of the two-dimensional ordered wrinkles to form multi-level wrinkles.
[0006] This invention is achieved through the following technical solutions:
[0007] A method for preparing a multi-level wrinkled polyaniline thin film with a two-dimensional inverse opal photonic crystal structure includes the following steps:
[0008] (1) Conductive glass for two-dimensional photonic crystal microspheres was prepared by gas-liquid self-assembly method;
[0009] (2) An electrochemical in-situ polymerization method was adopted, using a three-electrode system with a platinum sheet as the counter electrode, Hg / Hg2SO4 as the reference electrode, a conductive glass carrying two-dimensional photonic crystal microspheres as the working electrode, and an acidic solution containing aniline as the electrolyte. The conductive glass electrode carrying two-dimensional photonic crystal microspheres was placed in the three-electrode system to obtain a two-dimensional photonic crystal microsphere / polyaniline film composite material.
[0010] (3) The two-dimensional photonic crystal microsphere / polyaniline film composite material was transferred to the surface of polydimethylsiloxane and a multi-level wrinkled polyaniline film with a two-dimensional inverse opal photonic crystal structure was prepared by mechanical stretching.
[0011] Preferably, step (1) is as follows: fill the container with water to about 2 / 3 of its volume, fix the clean glass plate at 45°, drop the microsphere solution onto the surface of the glass plate, and under the action of gravity, the microsphere solution self-assembles on the water surface through the gas-liquid self-organization method. Then, insert the conductive glass plate into the water and slowly transfer the microsphere from the water surface to the conductive glass to obtain the conductive glass of the two-dimensional photonic crystal microsphere.
[0012] Further preferably, the microspheres are polystyrene microspheres, and the solvent for the microsphere solution is a mixture of water and n-propanol or water and ethanol. The diameter of the polystyrene microspheres is 100-5000 nm. The volume ratio of water to n-propanol in the mixture is 4:1-1:2, and the volume ratio of water to ethanol is 4:1-1:2.
[0013] Further preferred, the mass concentration of the microsphere solution is 1%-10%, and the dropping rate of the microsphere solution is 0.5-5 mL / h. The microspheres are dropped onto the surface of the glass slide using a micro-injection pump.
[0014] Preferably, step (2), which involves placing the conductive glass electrode carrying the two-dimensional photonic crystal microspheres in a three-electrode system to obtain the two-dimensional photonic crystal microsphere / polyaniline film composite material, involves placing the conductive glass electrode carrying the two-dimensional photonic crystal microspheres in a three-electrode system, and first applying a voltage of 100-200 mV / s. -1 The scanning speed was cyclically repeated 10 times within the potential range of 1.2V (vs. NHE) to 0.0V (vs. NHE) to complete the potentiodynamic polymerization, and then the current density was 0.1-0.5mA cm⁻¹. -2 Under the conditions of constant current method, the polymer was repolymerized for 10-60 min. Finally, the working electrode was removed, washed with deionized water and dried to obtain a two-dimensional photonic crystal microsphere / polyaniline film composite material.
[0015] Further preferably, the acidic solution of aniline is a mixture of aniline and sulfuric acid or a mixture of aniline and oxalic acid, wherein the molar concentration of aniline in the mixture of aniline and sulfuric acid is 0.1–0.5 mol / L. -1 The molar concentration of sulfuric acid is 0.1–0.5 mol / L. -1 In a mixed solution of aniline and oxalic acid, the molar concentration of aniline is 0.1–0.5 mol / L. -1 The molar concentration of oxalic acid is 0.1–1.0 mol / L. -1 .
[0016] Preferably, step (3) consists of the following steps:
[0017] S1: Place the two-dimensional photonic crystal microsphere / polyaniline film composite material obtained in step (2) into the immersion solution, etch away the polystyrene microspheres, and obtain a polyaniline film with a two-dimensional inverse opal photonic crystal structure. Wash with water and dry.
[0018] S2: Take a polyvinyl alcohol aqueous solution and use the casting method to uniformly cast a layer of polyvinyl alcohol film on a polyaniline film with a two-dimensional inverse opal photonic crystal structure. After drying, the thickness of the polyvinyl alcohol film is 30-100μm, thus obtaining a polyaniline / polyvinyl alcohol composite film with a two-dimensional inverse opal photonic crystal structure.
[0019] S3: Slowly peel off the polyaniline / polyvinyl alcohol composite film with the two-dimensional opal photonic crystal structure and soak it in water overnight until the polyvinyl alcohol is completely dissolved in the water;
[0020] S4: PDMS is stretched to a certain deformation, and a polyaniline film with a two-dimensional inverse opal photonic crystal structure in water is transferred to the PDMS surface, wherein the surface of the film with the two-dimensional inverse opal photonic crystal structure faces upward, thus obtaining a polyaniline / PDMS composite film with a two-dimensional inverse opal photonic crystal structure.
[0021] S5: Dry the polyaniline / PDMS composite film with a two-dimensional inverse opal photonic crystal structure and slowly release the deformation to obtain a multi-level wrinkled polyaniline film with a two-dimensional inverse opal photonic crystal structure.
[0022] The polyvinyl alcohol aqueous solution is prepared by the following steps: polyvinyl alcohol is mixed with water, heated to 85°C, and stirred for 3 hours to obtain a polyvinyl alcohol aqueous solution with a mass percentage of 1%-5%.
[0023] Further preferably, the soaking solution in step S1 is selected from at least one of toluene, tetrahydrofuran, N,N-dimethylformamide and dichloromethane, the polyvinyl alcohol aqueous solution in step S2 has a mass percentage of 1%-5%, and the PDMS stretching deformation in step S4 is 10%-50%.
[0024] This invention also protects the multi-level wrinkled polyaniline thin film with a two-dimensional inverse opal photonic crystal structure obtained by the above preparation method. This invention prepares two-dimensional ordered polyaniline wrinkles using a two-dimensional photonic crystal microsphere array, and constructs regular micro / nano structures on the surface of the two-dimensional ordered wrinkles to form multi-level wrinkles.
[0025] This invention also protects the application of multi-level wrinkled polyaniline films with a two-dimensional inverse opal photonic crystal structure in the construction of surface micropatterns.
[0026] Compared with the prior art, the beneficial effects of the present invention are:
[0027] (1) The present invention prepares a multi-level wrinkled polyaniline film with a two-dimensional inverse opal photonic crystal structure by combining a two-dimensional photonic crystal microsphere array, polyaniline and PDMS deformation. The reaction conditions of this preparation method are easy to control and the cost is low.
[0028] (2) In this invention, a two-dimensional photonic crystal microsphere / polyaniline film composite material is transferred to polydimethylsiloxane (PDMS) using a polyvinyl alcohol water-soluble film. The multi-level wrinkled polyaniline film is prepared by mechanical stretching, which is a simple process.
[0029] (3) This invention is the first to combine the inverse opal photonic crystal structure with the wrinkled structure to design multi-level wrinkles. Attached Figure Description
[0030] Figure 1This is a flowchart illustrating the process of self-assembly of polystyrene microspheres on the water surface in Example 1.
[0031] Figure 2 This is an appearance diagram of the conductive glass containing two-dimensional photonic crystal microspheres in Example 1.
[0032] Figure 3 This is a microscopic morphology diagram of the surface of two-dimensional photonic crystal microspheres on conductive glass in Example 1.
[0033] Figure 4 This is an appearance image of a polyaniline thin film sample with a two-dimensional inverse opal photonic crystal structure, as shown in Example 1.
[0034] Figure 5 Microstructure of polyaniline thin film with two-dimensional inverse opal photonic crystal structure.
[0035] Figure 6 The image shows the appearance of PDMS stretched to 30% deformation in Example 1.
[0036] Figure 7 This is a sample appearance image of the polyaniline film with a two-dimensional inverse opal photonic crystal structure after it was transferred to the PDMS surface in Example 1.
[0037] Figure 8 The microstructure of the multi-level wrinkled polyaniline surface with a two-dimensional inverse opal photonic crystal structure is shown in Example 1.
[0038] Figure 9 Example 2 shows the microstructure of a multi-level wrinkled polyaniline surface with a two-dimensional inverse opal photonic crystal structure.
[0039] Figure 10 Example 3 shows the microstructure of a multi-level wrinkled polyaniline surface with a two-dimensional inverse opal photonic crystal structure.
[0040] Figure 11 The microstructure of the multi-level wrinkled polyaniline surface with a two-dimensional inverse opal photonic crystal structure is shown in Comparative Example 1.
[0041] Figure 12 The microstructure of the polyaniline film with a two-dimensional photonic crystal structure is shown in Comparative Example 2. Detailed Implementation
[0042] The present invention will be further described in detail below with reference to the embodiments. These embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. Experimental methods in the following embodiments that do not specify specific conditions are generally performed under conventional conditions in the art or as recommended by the manufacturer; raw materials and reagents used, unless otherwise specified, are considered to be commercially available through conventional markets. The amounts of each component are expressed in parts by mass (g, mL).
[0043] Example 1
[0044] A method for preparing a multi-level wrinkled polyaniline thin film with a two-dimensional inverse opal photonic crystal structure includes the following steps:
[0045] (1) Fill a 12cm diameter petri dish with about 2 / 3 of its capacity with water. Fix a clean glass slide at 45°. Using a microinjection pump, add microspheres to the surface of the glass slide at a rate of 1mL / h. Under the influence of gravity, the polystyrene microsphere solution self-assembles on the water surface through a gas-liquid self-organization method. The process flow is as follows: Figure 1 As shown in the figure. The polystyrene microspheres have a diameter of 500 nm, the polystyrene microsphere solution has a mass concentration of 5%, and the solvent of the polystyrene microsphere solution consists of water and n-propanol in a volume ratio of 3:1. Subsequently, a conductive glass plate is inserted into water, and the polystyrene microspheres are slowly transferred from the water surface to the conductive glass. After drying, a conductive glass loaded with two-dimensional photonic crystal microspheres is obtained. The appearance of the conductive glass loaded with two-dimensional photonic crystal microspheres is shown in the figure. Figure 2 As shown. Scanning electron microscopy was used to characterize the surface microstructure of the microspheres on the conductive glass, as shown. Figure 3 As shown.
[0046] (2) An electrochemical in-situ polymerization method was adopted, using a three-electrode system. A platinum sheet was used as the counter electrode, Hg / Hg2SO4 as the reference electrode, and a conductive glass electrode carrying two-dimensional photonic crystal microspheres was used as the working electrode. An acidic solution containing aniline was used as the electrolyte. The electrochemical in-situ polymerization of polyaniline adopted a two-step polymerization method. The conductive glass electrode carrying two-dimensional photonic crystal microspheres was placed in the three-electrode system. First, a 100mV s⁻¹ polymerization was started. -1 The scanning speed was cyclically repeated 10 times within the potential range of 1.2V (vs. NHE) to 0.0V (vs. NHE) to complete the potentiodynamic polymerization, and then the current density was 0.1mA cm⁻¹. -2 Under the specified conditions, a constant current method was used for repolymerization for 10 min. Finally, the working electrode was removed, washed with deionized water, and dried to obtain a two-dimensional photonic crystal microsphere / polyaniline film composite material. The acidic electrolyte for aniline was a mixed solution of aniline and oxalic acid, with an aniline molar concentration of 0.1 mol / L. -1 The molar concentration of oxalic acid is 1 mol L. -1 .
[0047] (3) The two-dimensional photonic crystal microsphere / polyaniline film composite material was placed in N,N-dimethylformamide to etch away the polystyrene microspheres, resulting in a polyaniline film with a two-dimensional inverse opal photonic crystal structure. The film was washed, dried, and the sample appearance is shown in the figure below. Figure 4 As shown, the surface of the polyaniline film with a two-dimensional inverse opal photonic crystal structure was characterized using scanning electron microscopy. The surface microstructure is as follows: Figure 5 As shown.
[0048] Polyvinyl alcohol (PVA) was mixed with water, heated to 85°C, and stirred for 3 hours to obtain a 3% (w / w) aqueous solution of PVA. A certain mass of the PVA solution was taken, and a layer of PVA was uniformly cast onto a polyaniline film with a two-dimensional inverse opal photonic crystal structure using a casting method. After drying, the PVA film thickness was 80 μm, resulting in a polyaniline / PVA composite film with a two-dimensional inverse opal photonic crystal structure. The polyaniline / PVA composite film with the two-dimensional inverse opal photonic crystal structure was slowly peeled off with a label and soaked in water overnight until the PVA was completely dissolved in the water.
[0049] (4) Stretch the PDMS to 30% deformation (see Figure 6 The polyaniline film with a two-dimensional inverse opal photonic crystal structure in water was transferred to the PDMS surface (see...). Figure 7 In this process, a polyaniline / PDMS composite film with a two-dimensional inverse opal photonic crystal structure is obtained with the thin film surface facing upwards. The polyaniline / PDMS composite film with the two-dimensional inverse opal photonic crystal structure is dried and its deformation is slowly released, resulting in a multi-level wrinkled polyaniline surface with a two-dimensional inverse opal structure. The microstructure of the multi-level wrinkled polyaniline surface with the two-dimensional inverse opal structure is characterized using scanning electron microscopy, such as... Figure 8 As shown.
[0050] This invention utilizes the self-organization of the liquid-gas interface to prepare nanoparticle thin films on conductive glass. For example... Figure 2 As shown, under the illumination of a mobile phone light, the thin film exhibits a blue-green structural color at a certain angle, and the color is angle-dependent. Figure 3 Scanning electron microscopy revealed that the two-dimensional polystyrene microsphere nanoparticles exhibit a uniform hexagonal close-packed periodic arrangement, with a particle size of 500 nm. Figure 4 This is an appearance image of a polyaniline thin film sample with a two-dimensional inverse opal photonic crystal structure. It appears light green and semi-transparent. Figure 5 The process involves first preparing a polyaniline film with a two-dimensional inverse opal photonic crystal structure using polystyrene microspheres as templates, and then etching away the microspheres with a solvent to obtain the final polyaniline film with a photonic crystal structure. Because... Figure 3 The microspheres are arranged in a periodic, uniform, hexagonal close-packed pattern, resulting in an inverse opal structure. This structure exhibits a typical periodic arrangement with uniform micropore size and high porosity. The pore size corresponds to the microsphere diameter and is approximately 500 nm. Figure 8 Example 1 shows that a two-dimensional inverse opal photonic crystal structure is embedded in the surface of polyaniline wrinkles to form a multi-level wrinkle pattern.
[0051] Example 2
[0052] A method for preparing a multi-level wrinkled polyaniline thin film with a two-dimensional inverse opal photonic crystal structure includes the following steps:
[0053] (1) Fill a 12cm diameter petri dish with about 2 / 3 water. Fix a clean glass slide at 45°. Using a microinjection pump, add microspheres to the surface of the glass slide at a rate of 5mL / h. Under the influence of gravity, the polystyrene microsphere solution self-assembles on the water surface through a gas-liquid self-organization method. The polystyrene microspheres have a diameter of 1000nm, the mass concentration of the polystyrene microsphere solution is 2.5%, and the solvent of the polystyrene microsphere solution is composed of water and ethanol in a volume ratio of 1:1. Subsequently, insert a conductive glass slide into the water and slowly transfer the microspheres from the water surface to the conductive glass to obtain a conductive glass containing two-dimensional photonic crystal microspheres.
[0054] (2) An electrochemical in-situ polymerization method was adopted, using a three-electrode system. A platinum sheet was used as the counter electrode, Hg / Hg2SO4 as the reference electrode, and a conductive glass electrode carrying two-dimensional photonic crystal microspheres was used as the working electrode. An acidic solution containing aniline was used as the electrolyte. The electrochemical in-situ polymerization of polyaniline adopted a two-step polymerization method. The conductive glass electrode carrying two-dimensional photonic crystal microspheres was placed in the three-electrode system. First, the polymerization was carried out at 200 mV s. -1 The scanning speed was cyclically repeated 10 times within the potential range of 1.2V (vs. NHE) to 0.0V (vs. NHE) to complete the potentiodynamic polymerization, and then the current density was 0.5mA cm⁻¹. -2 Under the specified conditions, repolymerization was carried out using a constant current method for 50 min. Finally, the working electrode was removed, washed with deionized water, and dried to obtain a two-dimensional photonic crystal microsphere / polyaniline film composite material. The acidic electrolyte for aniline was a mixture of aniline and sulfuric acid, with an aniline molar concentration of 0.4 mol / L. -1 The molar concentration of sulfuric acid is 0.3 mol / L. -1 .
[0055] (3) The above two-dimensional photonic crystal microsphere / polyaniline film composite material was placed in dichloromethane to etch away the polystyrene microspheres, and a polyaniline film with a two-dimensional inverse opal photonic crystal structure was obtained. The film was then washed with water and dried.
[0056] Polyvinyl alcohol (PVA) was mixed with water, heated to 85°C, and stirred for 3 hours to obtain a 3% (w / w) aqueous solution of PVA. A certain mass of the PVA solution was taken, and a layer of PVA was uniformly cast onto a polyaniline film with a two-dimensional inverse opal photonic crystal structure using a casting method. After drying, the PVA film thickness was 30 μm, resulting in a polyaniline / PVA composite film with a two-dimensional inverse opal photonic crystal structure. The polyaniline / PVA composite film with the two-dimensional inverse opal photonic crystal structure was slowly peeled off with a label and soaked in water overnight until the PVA was completely dissolved in the water.
[0057] (4) PDMS was stretched to 20% deformation, and a polyaniline film with a two-dimensional inverse opal photonic crystal structure was transferred from water to the PDMS surface, with the surface of the film with the two-dimensional inverse opal photonic crystal structure facing upwards, resulting in a polyaniline / PDMS composite film with a two-dimensional inverse opal photonic crystal structure. The polyaniline / PDMS composite film with the two-dimensional inverse opal photonic crystal structure was dried and the deformation was slowly released to obtain a multi-level wrinkled polyaniline surface with a two-dimensional inverse opal photonic crystal structure. The microstructure of the multi-level wrinkled polyaniline surface with a two-dimensional inverse opal photonic crystal structure was characterized by scanning electron microscopy, such as... Figure 9 As shown.
[0058] Figure 9 Example 2 shows the microscopic surface of polyaniline with two-dimensional inverse opal photonic crystal multilevel wrinkles. It can be seen that, through the control of different conditions, the amplitude, period and orientation of the wrinkles are highly ordered.
[0059] Example 3
[0060] A method for preparing a multi-level wrinkled polyaniline thin film with a two-dimensional inverse opal photonic crystal structure includes the following steps:
[0061] (1) Fill a 12cm diameter petri dish with about 2 / 3 of its volume with water. Fix a clean glass slide at 45°. Using a microinjection pump, add microspheres to the surface of the glass slide at a rate of 3mL / h. Under the influence of gravity, the polystyrene microsphere solution self-assembles on the water surface through a gas-liquid self-organization method. The polystyrene microspheres have a diameter of 100nm, the mass concentration of the polystyrene microsphere solution is 10%, and the solvent of the polystyrene microsphere solution consists of water and ethanol in a volume ratio of 1:2. Subsequently, insert a conductive glass slide into the water and slowly transfer the microspheres from the water surface to the conductive glass to obtain a conductive glass containing two-dimensional photonic crystal microspheres.
[0062] (2) An electrochemical in-situ polymerization method was adopted, using a three-electrode system. A platinum sheet was used as the counter electrode, Hg / Hg2SO4 as the reference electrode, and a conductive glass electrode carrying two-dimensional photonic crystal microspheres was used as the working electrode. An acidic solution containing aniline was used as the electrolyte. The electrochemical in-situ polymerization of polyaniline adopted a two-step polymerization method. The conductive glass electrode carrying two-dimensional photonic crystal microspheres was placed in the three-electrode system. First, a 30mV s⁻¹ polymerization was started. -1 The scanning speed was cyclically repeated 10 times within the potential range of 1.2V (vs. NHE) to 0.0V (vs. NHE) to complete the potentiodynamic polymerization, and then the current density was 0.3mA cm⁻¹. -2 Under the specified conditions, repolymerization was carried out using a constant current method for 30 minutes. Finally, the working electrode was removed, washed with deionized water, and dried to obtain a two-dimensional photonic crystal microsphere / polyaniline film composite material. The acidic electrolyte for aniline was a mixture of aniline and sulfuric acid, with an aniline molar concentration of 0.5 mol / L. -1 The molar concentration of sulfuric acid is 0.5 mol / L. -1 .
[0063] (3) The above-mentioned two-dimensional inverse opal photonic crystal microsphere / polyaniline film composite material was placed in toluene to etch away the polystyrene microspheres, and a polyaniline film with a two-dimensional inverse opal photonic crystal structure was obtained. The film was then washed with water and dried.
[0064] Polyvinyl alcohol (PVA) was mixed with water, heated to 85°C, and stirred for 3 hours to obtain a 3% (w / w) aqueous solution of PVA. A certain mass of the PVA aqueous solution was taken, and a layer of PVA film was uniformly cast onto a polyaniline film with a two-dimensional inverse opal photonic crystal structure using a casting method. After drying, the thickness of the PVA film was 50 μm, resulting in a polyaniline / PVA composite film with a two-dimensional inverse opal photonic crystal structure.
[0065] (4) Slowly peel off the polyaniline / polyvinyl alcohol composite film with the two-dimensional inverse opal photonic crystal structure using a label, and soak it in water overnight until the polyvinyl alcohol is completely dissolved in the water. Stretch the PDMS to 50% deformation and transfer the polyaniline film with the two-dimensional inverse opal photonic crystal structure from the water to the PDMS surface, with the surface of the film with the two-dimensional inverse opal photonic crystal structure facing upwards, to obtain a polyaniline / PDMS composite film with a two-dimensional inverse opal photonic crystal structure. Dry the polyaniline / PDMS composite film with the two-dimensional inverse opal photonic crystal structure and slowly release the deformation to obtain a multi-level wrinkled polyaniline film with a two-dimensional inverse opal photonic crystal structure. Characterize the surface micromorphology of the multi-level wrinkled polyaniline with the two-dimensional inverse opal photonic crystal structure using scanning electron microscopy, such as... Figure 10 As shown.
[0066] Figure 10The microscopic surface of the two-dimensional inverse opal photonic crystal polyaniline multi-level wrinkles in Example 3 shows that the amplitude, period, and orientation order of the wrinkles are poor. This is because the microscopic surface of the wrinkles is jointly controlled by factors such as the potential polymerization conditions, the thickness of the polyvinyl alcohol film, and the deformation of the PDMS. Under potential polymerization conditions of 0.1-0.5 mA cm⁻¹... -2 Under these conditions, the polyvinyl alcohol film is repolymerized for 10-50 minutes using a constant current method, with a film thickness of 30-80 μm. The PDMS is stretched to 20%-30% deformation, resulting in wrinkles with high amplitude, period, and orientation order.
[0067] Example 4
[0068] Similar to Example 1, except that: in step (1), the mass concentration of the microsphere solution is 1%, and the dropping rate of the microsphere solution is 0.5 mL / h; in step (2), the scanning rate in the potentiodynamic polymerization is 100 mV / s. -1 In the constant current method, the current density is 0.1 mA cm⁻¹ -2 In the constant current method, the polymerization time is 60 min; in step (3), the thickness of the polyvinyl alcohol film is 100 μm, the mass percentage of the polyvinyl alcohol aqueous solution is 5%, and the PDMS stretching deformation is 10%.
[0069] Example 5
[0070] Similar to Example 1, except that: in step (1), the mass concentration of the microsphere solution is 10%, and the dropping rate of the microsphere solution is 5 mL / h; in step (2), the scanning rate in the potentiodynamic polymerization is 200 mV / s. -1 In the constant current method, the current density is 0.5 mA / cm². -2 In the constant current method, the polymerization time is 30 min; in step (3), the thickness of the polyvinyl alcohol film is 30 μm, the mass percentage of the polyvinyl alcohol aqueous solution is 1%, and the stretching deformation of PDMS is 50%.
[0071] Comparative Example 1
[0072] A method for preparing a multi-level wrinkled polyaniline thin film with a two-dimensional inverse opal photonic crystal structure includes the following steps:
[0073] (1) Fill a 12cm diameter petri dish with about 2 / 3 water. Fix a clean glass slide at 45°. Using a microinjection pump, add microspheres to the surface of the glass slide at a rate of 1mL / h. Under the influence of gravity, the polystyrene microsphere solution self-assembles on the water surface through a gas-liquid self-organization method. The polystyrene microspheres have a diameter of 500nm, the mass concentration of the polystyrene microsphere solution is 5%, and the solvent of the polystyrene microsphere solution is composed of water and n-propanol in a volume ratio of 3:1. Subsequently, insert a conductive glass slide into the water and slowly transfer the microspheres from the water surface to the conductive glass to obtain a conductive glass containing two-dimensional photonic crystal microspheres.
[0074] (2) An electrochemical in-situ polymerization method was adopted, using a three-electrode system. A platinum sheet was used as the counter electrode, Hg / Hg2SO4 as the reference electrode, and a conductive glass electrode carrying two-dimensional photonic crystal microspheres was used as the working electrode. An acidic solution containing aniline was used as the electrolyte. The electrochemical in-situ polymerization of polyaniline adopted a two-step polymerization method. The conductive glass electrode carrying two-dimensional photonic crystal microspheres was placed in the three-electrode system. First, a 100mV s⁻¹ polymerization was started. -1 The scanning speed was cyclically repeated 10 times within the potential range of 1.2V (vs. NHE) to 0.0V (vs. NHE) to complete the potentiodynamic polymerization, and then the current density was 0.1mA cm⁻¹. -2 Under the specified conditions, a constant current method was used for repolymerization for 10 min. Finally, the working electrode was removed, washed with deionized water, and dried to obtain a two-dimensional photonic crystal microsphere / polyaniline film composite material. The acidic electrolyte for aniline consisted of aniline and oxalic acid, with an aniline molar concentration of 0.1 mol / L. -1 The molar concentration of oxalic acid is 1 mol L. -1 .
[0075] (3) The above-mentioned two-dimensional inverse opal photonic crystal microsphere / polyaniline film composite material was placed in toluene to etch away the polystyrene microspheres, and a polyaniline film with a two-dimensional inverse opal photonic crystal structure was obtained. The film was then washed with water and dried.
[0076] Polyvinyl alcohol (PVA) was mixed with water, heated to 85°C, and stirred for 3 hours to obtain a 3% (w / w) PVA solution. A certain mass of the PVA solution was taken, and a layer of PVA film was uniformly cast onto a polyaniline film with a two-dimensional inverse opal photonic crystal structure using a casting method. After drying, the thickness of the PVA film was 80 μm, resulting in a polyaniline / PVA composite film with a two-dimensional inverse opal photonic crystal structure.
[0077] (4) Slowly peel off the polyaniline / polyvinyl alcohol composite film with the two-dimensional inverse opal photonic crystal structure using a label, and soak it in water overnight until the polyvinyl alcohol is completely dissolved in the water. Transfer the polyaniline film with the two-dimensional inverse opal photonic crystal structure in the water to the PDMS surface, stretch the PDMS to 30% deformation, with the film surface with the two-dimensional inverse opal photonic crystal structure facing upwards, to obtain a polyaniline / PDMS composite film with the two-dimensional inverse opal photonic crystal structure. Dry the polyaniline / PDMS composite film with the two-dimensional inverse opal photonic crystal structure and slowly release the deformation to obtain a multi-level wrinkled polyaniline film with the two-dimensional inverse opal photonic crystal structure. Characterize the surface micromorphology of the multi-level wrinkled polyaniline with the two-dimensional inverse opal photonic crystal structure using scanning electron microscopy, such as... Figure 11 As shown.
[0078] Figure 11 Comparative Example 1 shows the microscopic surface of polyaniline with multi-level wrinkles in a two-dimensional inverse opal photonic crystal. Compared with Example 1, it can be seen that when a polyaniline film with a two-dimensional inverse opal photonic crystal structure is transferred to the PDMS surface and then the PDMS is stretched to a certain deformation, the amplitude, period, and orientation order of the multi-level wrinkled microscopic surface become very poor. Since the polyaniline film is not elastic, it will break and generate holes during the process of stretching it simultaneously with the PDMS.
[0079] Comparative Example 2
[0080] A method for preparing a multi-level wrinkled polyaniline thin film with a two-dimensional inverse opal photonic crystal structure includes the following steps:
[0081] (1) Fill a 12cm diameter petri dish with about 2 / 3 of its volume with water. Fix a clean glass slide at 45° and use a microinjection pump to drop microspheres onto the glass slide surface at a rate of 1mL / h. Under the influence of gravity, the polystyrene microsphere solution is self-assembled on the water surface through a gas-liquid self-organization method. The polystyrene microspheres have a diameter of 500nm, the mass concentration of the polystyrene microsphere solution is 5%, and the solvent of the polystyrene microsphere solution is composed of water and n-propanol in a volume ratio of 3:1. Subsequently, insert a conductive glass slide into the water and slowly transfer the microspheres from the water surface to the conductive glass. The surface micromorphology of the microspheres on the conductive glass is characterized by scanning electron microscopy, resulting in a conductive glass containing two-dimensional photonic crystal microspheres.
[0082] (2) An electrochemical in-situ polymerization method was adopted, using a three-electrode system. A platinum sheet was used as the counter electrode, Hg / Hg2SO4 as the reference electrode, and a conductive glass electrode carrying two-dimensional photonic crystal microspheres was used as the working electrode. An acidic solution containing aniline was used as the electrolyte. The electrochemical in-situ polymerization of polyaniline adopted a two-step polymerization method. The conductive glass electrode carrying two-dimensional photonic crystal microspheres was placed in the three-electrode system. First, a 100mV s⁻¹ polymerization was started. -1 The scanning speed was cyclically repeated 10 times within the potential range of 1.2V (vs. NHE) to 0.0V (vs. NHE) to complete the potentiodynamic polymerization, and then the current density was 0.1mA cm⁻¹. -2 Under the specified conditions, a constant current method was used for repolymerization for 10 min. Finally, the working electrode was removed, washed with deionized water, and dried to obtain a two-dimensional photonic crystal microsphere / polyaniline film composite material. The acidic electrolyte for aniline was a mixture of aniline and oxalic acid, with an aniline molar concentration of 0.1 mol / L. -1 The molar concentration of oxalic acid is 1 mol L. -1 .
[0083] (3) The above two-dimensional photonic crystal microsphere / polyaniline film composite material is washed with water and dried.
[0084] Polyvinyl alcohol (PVA) was mixed with water, heated to 85°C, and stirred for 3 hours to obtain a 3% (w / w) aqueous solution of PVA. A certain mass of the PVA aqueous solution was taken, and a layer of PVA film was uniformly cast onto a polyaniline film composite material with a two-dimensional photonic crystal structure using a casting method. After drying, the PVA film thickness was 80 μm, resulting in a polyaniline / PVA composite film with a two-dimensional photonic crystal structure. The polyaniline / PVA composite film with the two-dimensional photonic crystal structure was slowly peeled off with a label and soaked in water overnight until the PVA was completely dissolved in the water.
[0085] (4) PDMS was stretched to 30% deformation, and a polyaniline film with a two-dimensional photonic crystal structure in water was transferred to the PDMS surface, with the surface of the film with the two-dimensional photonic crystal structure facing upwards, resulting in a polyaniline / PDMS composite film with a two-dimensional photonic crystal structure. The polyaniline / PDMS composite film with the two-dimensional photonic crystal structure was dried and the deformation was slowly released to obtain a multi-level wrinkled polyaniline surface with a two-dimensional photonic crystal structure. The microstructure of the multi-level wrinkled polyaniline surface with a two-dimensional inverse opal photonic crystal structure was characterized by scanning electron microscopy, such as... Figure 12 As shown.
[0086] Figure 12 Comparative Example 2 shows the microscopic surface of polyaniline with two-dimensional photonic crystal multilevel wrinkles. Compared with Example 1, it can be seen that the surface of the microspheres was not etched with solvent, and the periodic arrangement of the multilevel wrinkled microscopic surface deteriorated.
[0087] The above description of the embodiments is only for the purpose of helping to understand the technical solution and core idea of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made to the present invention without departing from the principle of the present invention, and these improvements and modifications also fall within the protection scope of the claims of the present invention.
Claims
1. A method for preparing a multi-level wrinkled polyaniline thin film with a two-dimensional inverse opal photonic crystal structure, characterized in that, Includes the following steps: (1) Conductive glass for two-dimensional photonic crystal microspheres was prepared by gas-liquid self-assembly; (2) An electrochemical in-situ polymerization method was adopted, using a three-electrode system with a platinum sheet as the counter electrode, Hg / Hg2SO4 as the reference electrode, and a conductive glass electrode carrying two-dimensional photonic crystal microspheres as the working electrode. An acidic solution containing aniline was used as the electrolyte. The conductive glass electrode carrying two-dimensional photonic crystal microspheres was placed in the three-electrode system, and the initial electrochemical reaction was carried out at 100-200 mV·s. -1 The scanning speed was cyclically repeated 10 times in the potential range of 1.2 V to 0.0 V to complete the potentiodynamic polymerization, and then the current density was 0.1-0.5 mA·cm⁻¹. -2 Under the conditions of constant current method, the polymer was repolymerized for 10-60 min. Finally, the working electrode was removed, washed with deionized water and dried to obtain a two-dimensional photonic crystal microsphere / polyaniline film composite material. (3) The two-dimensional photonic crystal microsphere / polyaniline film composite material is transferred to the surface of polydimethylsiloxane, and a multi-level wrinkled polyaniline film with a two-dimensional inverse opal photonic crystal structure is prepared by mechanical stretching. The specific steps of step (3) are as follows: S1: The two-dimensional photonic crystal microsphere / polyaniline film composite material obtained in step (2) is placed in the immersion solution, the polystyrene microspheres are etched away, and a polyaniline film with a two-dimensional inverse opal photonic crystal structure is obtained. The film is then washed with water and dried. S2: Take a polyvinyl alcohol aqueous solution and use the casting method to uniformly cast a layer of polyvinyl alcohol film on a polyaniline film with a two-dimensional inverse opal photonic crystal structure. After drying, the thickness of the polyvinyl alcohol film is 30-100 μm, thus obtaining a polyaniline / polyvinyl alcohol composite film with a two-dimensional inverse opal photonic crystal structure. S3: Slowly peel off the polyaniline / polyvinyl alcohol composite film with the two-dimensional inverse opal photonic crystal structure, soak it in water overnight, until the polyvinyl alcohol is completely dissolved in the water; S4: PDMS is stretched to a certain deformation, and a polyaniline film with a two-dimensional inverse opal photonic crystal structure in water is transferred to the PDMS surface, wherein the surface of the film with the two-dimensional inverse opal photonic crystal structure faces upward, to obtain a polyaniline / PDMS composite film with a two-dimensional inverse opal photonic crystal structure. The PDMS stretching deformation is 10%-50%. S5: Dry the polyaniline / PDMS composite film with a two-dimensional inverse opal photonic crystal structure and slowly release the deformation to obtain a multi-level wrinkled polyaniline film with a two-dimensional inverse opal photonic crystal structure.
2. The preparation method according to claim 1, characterized in that, Step (1) is as follows: Fill the container with water to 2 / 3 of its volume, fix the clean glass plate at 45°, drop the microsphere solution onto the surface of the glass plate, and under the action of gravity, the microsphere solution self-assembles on the water surface through the gas-liquid self-organization method. Then, insert the conductive glass plate into the water and slowly transfer the microsphere from the water surface to the conductive glass to obtain the conductive glass of the two-dimensional photonic crystal microsphere.
3. The preparation method according to claim 2, characterized in that, The microspheres are polystyrene microspheres, and the solvent for the microsphere solution is a mixture of water and n-propanol or water and ethanol.
4. The preparation method according to claim 2 or 3, characterized in that, The mass concentration of the microsphere solution is 1%-10%, and the dropping rate of the microsphere solution is 0.5-5 mL / h.
5. The preparation method according to claim 1, characterized in that, The acidic solution of aniline is a mixture of aniline and sulfuric acid or a mixture of aniline and oxalic acid. In the mixture of aniline and sulfuric acid, the molar concentration of aniline is 0.1–0.5 mol·L⁻¹. -1 The molar concentration of sulfuric acid is 0.1~0.5 mol·L⁻¹. -1 In a mixed solution of aniline and oxalic acid, the molar concentration of aniline is 0.1–0.5 mol·L⁻¹. -1 The molar concentration of oxalic acid is 0.1~1.0 mol·L⁻¹. -1 .
6. The preparation method according to claim 1, characterized in that, The soaking solution in step S1 is selected from at least one of toluene, tetrahydrofuran, N,N-dimethylformamide and dichloromethane, and the polyvinyl alcohol aqueous solution in step S2 has a mass percentage of 1%-5%.
7. The multi-level wrinkled polyaniline film with a two-dimensional inverse opal photonic crystal structure obtained by the preparation method according to any one of claims 1-6.
8. The application of the multi-level wrinkled polyaniline film with a two-dimensional inverse opal photonic crystal structure as described in claim 7 in the construction of surface micropatterns.