A polyaniline conductive ink, a preparation method and application thereof

Abstract

This invention relates to the field of new materials technology, and more particularly to a polyaniline conductive ink and its preparation method, as well as the application of this ink in flexible electronic devices, especially micro supercapacitors. A polyaniline conductive ink comprises, by weight, 10-30 parts of conductive filler; 18-30 parts of binder; 32-69 parts of solvent; and 3-8 parts of additives; wherein the conductive filler is composed of graphite, carbon black, and polyaniline. The polyaniline conductive ink of this invention solves the problem that existing conductive inks struggle to simultaneously achieve high conductivity, excellent mechanical flexibility, and high energy storage capacity.

Description

Technical Field

[0001] This invention relates to the field of new materials technology, and in particular to a polyaniline conductive ink and its preparation method, as well as the application of the ink in flexible electronic devices, especially micro supercapacitors. Background Technology

[0002] In recent years, with the rapid development of new energy and electronic information industries, and the rise of emerging product markets such as smartphones and wearable smart devices, printed electronics technology has achieved remarkable results. This technology has been widely applied in fields such as flexible conductive circuits, antenna equipment, sensors, wearable devices, and nanorobots. Conductive ink, as the core of printed electronics technology, can be used to print patterns onto various substrates and assemble them into functional devices.

[0003] Polyaniline is a polymer compound with unique electrical and optical properties, exhibiting excellent conductivity and electrochemical performance after doping. Currently, existing carbon-based conductive inks mainly use carbon materials such as graphite and carbon black, which, while possessing good conductivity, are insufficient in energy storage. While pure polyaniline material exhibits pseudocapacitive properties, its processing performance is poor, and it is difficult to prepare stable flexible printing inks on its own. How to effectively introduce polyaniline into carbon-based ink systems to significantly improve the electrochemical energy storage performance of the ink while maintaining high conductivity and flexibility is a pressing technical problem that needs to be solved. Summary of the Invention

[0004] The purpose of this invention is to provide a polyaniline conductive ink to solve the problem that existing conductive inks cannot simultaneously achieve high conductivity, excellent mechanical flexibility, and high energy storage capacity.

[0005] The technical solution adopted by this invention to solve its technical problem is:

[0006] A polyaniline conductive ink comprises, by weight, 10-30 parts of conductive filler; 18-30 parts of binder; 32-69 parts of solvent; and 3-8 parts of additives; wherein the conductive filler is composed of graphite, carbon black, and polyaniline.

[0007] Preferably, in the conductive filler, the mass ratio of graphite to carbon black is (4.5-5.5):1 (most preferably 5:1), and the mass ratio of polyaniline to carbon black is 1:1 to 2:1.

[0008] Preferably, the mass ratio of graphite, carbon black and polyaniline in the conductive filler is 5:1:1.5.

[0009] Preferably, the graphite has an average particle size of 1000-3000 mesh; the carbon black has an average particle size of 10-18 nm; and the polyaniline has an average particle size of 15-20 nm.

[0010] The selection of large-size graphite sheets can effectively reduce the contact resistance between graphite sheets. The addition of small-particle carbon black and polyaniline can be more uniformly dispersed on the graphite sheets, preventing the graphite sheets from agglomerating and stacking while providing more longitudinal conductive paths, thereby improving the overall conductivity of the material. At the same time, because polyaniline has tunable pseudocapacitive properties due to its different oxidation states, it can be used in capacitors to improve their performance.

[0011] Preferably, the adhesive is a waterborne polyurethane; more preferably, the waterborne polyurethane is F0407 type waterborne polyurethane or F0410 type waterborne polyurethane.

[0012] Preferably, the solvent is water; the additives include at least two of the following: water-based defoamer, water-based carbon black dispersant, sodium carboxymethyl cellulose, and ethylene glycol.

[0013] Preferably, the water-based defoamer includes one of BYK028, BYK022, and BYK011 defoamers, and more preferably BYK028 defoamer.

[0014] Preferably, the aqueous carbon black dispersant includes one of DS-W72H, AKN-2076, and T-859 dispersants, more preferably T-859 dispersant.

[0015] Preferably, the raw materials of the polyaniline conductive ink, by weight, include: 25-30 parts of conductive filler and 25-30 parts of water-based polyurethane binder.

[0016] 35-55 parts water, 3-6 parts additives; the conductive filler is composed of graphite, carbon black and polyaniline.

[0017] A method for preparing polyaniline conductive ink according to the present invention includes the following steps: S1, mixing conductive filler, binder, additive and solvent, and stirring and dispersing to obtain a preliminary mixed ink; S2, ball milling the preliminary mixed ink to obtain the polyaniline conductive ink.

[0018] Preferably, in step S1, the stirring and dispersing speed is 1000-4000 r / min and the time is 4-6 h; in step S2, the ball milling speed is 300-1500 r / min and the time is 4-6 h.

[0019] More preferably, in step S1, the dispersion is carried out at a speed of 3000 r / min for 4 hours, and in step S2, the ball milling speed is 1200 r / min and the ball milling time is 4 hours.

[0020] An application of the polyaniline conductive ink described in this invention in the field of flexible electronics.

[0021] Preferably, the application specifically involves printing the polyaniline conductive ink onto a substrate to prepare a flexible circuit or electrode; more preferably, the application includes assembling the polyaniline conductive ink as an electrode material into an all-solid-state micro supercapacitor.

[0022] Preferably, the substrate includes a paper substrate or a polyethylene terephthalate (PET) substrate; the post-printing process further includes a drying step at 25-180°C for 2-12 hours.

[0023] This invention also provides the application of the above-mentioned ink in the field of flexible electronics, particularly in all-solid-state micro supercapacitors.

[0024] The beneficial effects of this invention are:

[0025] 1. This invention utilizes dispersion and ball milling processes to peel large-sized graphite into thinner few-layer graphite sheets (F-GT) using strong mechanical shearing force. Simultaneously, small-diameter carbon black (CB) and polyaniline (PANI) particles are uniformly dispersed and densely embedded between the graphite sheets. In this structure, the carbon black acts as a conductive bridge, effectively preventing the graphite sheets from agglomerating and stacking, reducing inter-sheet contact resistance, and providing more longitudinal conductive paths.

[0026] 2. In this invention, the polyaniline is refined and uniformly distributed between the graphite layers through ball milling. This not only does not damage the conductive network but also provides a large number of pseudocapacitive reactive sites. Experiments show that, compared with inks without added polyaniline, the areal capacitance of the microcapacitors prepared with the ink of this invention is 10.65 mF cm⁻¹. -2 Significantly increased to 95.8 mF cm -2 The energy density is significantly improved, thus significantly enhancing the energy storage performance of the product.

[0027] 3. The electrodes prepared using the ink described in this invention retain a capacitance of nearly 90% after 1000 bending cycles, and exhibit stable performance after series-parallel integration, demonstrating excellent mechanical flexibility.

[0028] Furthermore, the ink described in this invention uses a water-based system, which is environmentally friendly; the main raw material, graphite, is inexpensive and the preparation process is simple, making it suitable for large-scale production. Attached Figure Description

[0029] Figure 1 The images shown are: (a) SEM image of the few-layer graphite after exfoliation, (b) SEM image of the few-layer graphite / carbon black / polyaniline, (c) XRD patterns of each component and the composite, and (d) Raman spectrum of the composite. Figure 2The images show (ab) AFM images and potential distribution diagrams, and (cd) AFM images and height distribution diagrams of the F-GT / CB / PANI ink film in Example 1. Figure 3 Examples of the following in Example 1 include: (a) ink viscosity test, (b) conductivity of inks with different proportions, (c) stability test, (d) mechanical flexibility test, (e) nano-indentation test, and (f) display of screen-printed patterns. Figure 4 (a) Cyclic voltammetry, (b) Constant current charge-discharge diagram, and (c) Impedance spectrum of the all-solid-state micro supercapacitor assembled in Example 1; Figure 5 The (ad) bending test performance and (ef) series-parallel integration performance test of the micro supercapacitor in Example 1; Figure 6 This demonstrates the application of the all-solid-state micro supercapacitor assembled in Example 1 in lighting a small light bulb. Detailed Implementation

[0030] The technical solution of the present invention will be further described in detail below through specific embodiments. It should be understood that the implementation of the present invention is not limited to the following embodiments, and any modifications and / or alterations made to the present invention will fall within the protection scope of the present invention.

[0031] In this invention, unless otherwise specified, all parts and percentages are by weight, and the equipment and raw materials used are commercially available or commonly used in the art. Unless otherwise specified, the methods in the following embodiments are conventional methods in the art.

[0032] Unless otherwise specified, the reagents used in the following examples can be purchased from a regular biochemical reagent store.

[0033] Example 1

[0034] Preparation of a polyaniline conductive ink:

[0035] S1. Weigh 18.65g graphite (particle size 1000-3000 mesh), 3.73g carbon black (particle size 15nm), 5.59g polyaniline (particle size 15-20nm), 2g water-based carbon black dispersant (T-859), 1g water-based defoamer (BYK028), 29g water-based polyurethane (F0407 type), and 39g deionized water. Add the above raw materials sequentially to a mixer and disperse at 3000r / min for 4 hours to obtain a preliminarily mixed ink.

[0036] S2. Place the pre-mixed ink into a ball mill jar and ball mill it using an omnidirectional planetary ball mill at a speed of 1200 r / min for 4 hours to obtain the final water-based polyaniline conductive ink (marked as F-GT / CB / PANI).

[0037] Comparative Example 1

[0038] To verify the role of polyaniline, a polyaniline-free conductive ink (labeled F-GT / CB) was prepared. Except for the absence of polyaniline, the proportions of other raw materials and the preparation process remained the same as in Example 1.

[0039] A circular pattern was designed using CAD software, and a 100-mesh screen printing template was created. The pattern was then printed onto a polyethylene terephthalate (PET) substrate using screen printing technology. The printed pattern was placed in an oven and dried at 60°C for 2 hours, allowing the ink to adhere to the PET substrate. The surface morphology was then analyzed using a scanning electron microscope. Figure 1 As shown.

[0040] Performance Characterization and Analysis

[0041] 1. Microscopic morphology and structural analysis

[0042] Figure 1 Examples 1 include: (a) SEM image of the exfoliated few-layer graphite; (b) SEM image of few-layer graphite / carbon black / polyaniline; (c) XRD patterns of PANI, CB, GT, and F-GT / CB; and (d) Raman spectra of F-GT / CB / PANI and F-GT / CB. It can be seen that the original graphite, after dispersion and ball milling, can be exfoliated into few-layer graphite flakes. Figure 1 (a) Furthermore, the carbon black particles (like black sesame seeds) are densely embedded on the graphite sheets, and this "conductive bridge" structure solves the problem of high contact resistance between graphite sheets. Meanwhile, the polyaniline particles are uniformly dispersed within the graphite, thanks to the ball milling process, and their particle size is significantly smaller than that of polyaniline. Figure 1 (b) This significantly increases the number of pseudocapacitive reactive sites. For example... Figure 1 As shown in (c), the original CB and PANI have much lower peak intensities compared to GT, exhibiting an amorphous structure. GT, on the other hand, shows a strong peak at 26.5°, indicating an excellent crystalline state. The decrease in peak intensity at 26.5° for F-GT / CB is due to the mechanical processing of high-speed dispersion and ball milling disrupting the original highly ordered layered structure of graphite, indicating the presence of a large amount of exfoliated few-layer graphite (multilayer graphene). The further significant decrease in peak intensity at 26.5° for F-GT / CB / PANI is due to both the disruption of the original highly ordered layered structure of graphite by high-speed dispersion and ball milling, and the uniform coating of polyaniline on the graphite sheet surface or filling the interlayer / particle gaps, consistent with the scanning results, forming a three-dimensional structure. Figure 1 (d) shows the Raman spectra of F-GT / CB and F-GT / CB / PANI at approximately 1349 cm⁻¹. -1 1580 cm-1 and 2725 cm -1 There are three distinct characteristic peaks at 1175 cm⁻¹, corresponding to the D, G, and 2D peaks, respectively. The D peak contains information about defects introduced by graphene, while the G peak represents the graphitized structure. Specifically, the intensity ratio (ID / IG) of the D and G peaks provides insight into the degree of disorder and defects in the structure. The ID / IG ratios of F-GT / CB and F-GT / CB / PANI are 0.49 and 0.68, respectively, indicating that the introduction of polyaniline further disrupted the ordered structure of the material. F-GT / CB / PANI shows a peak at 1175 cm⁻¹. -1 1220 cm -1 1480 cm -1 Three additional characteristic peaks were observed, at 1180 cm⁻¹. -1 The characteristic peak is related to the CH bending vibration of the benzene ring, 1220 cm⁻¹ -1 The characteristic peaks are related to the CN stretching vibrations of the benzene ring, which are characteristic of the conductive structure of PANI, at 1480 cm⁻¹. -1 The characteristic peak at the point is related to the C=N vibration of the quinone ring, which proves the successful composite of polyaniline and the further disordering of the structure, which is conducive to the intercalation of ions.

[0043] 2. Electrical conductivity and rheological properties

[0044] Figure 2 Examples 1 show (a) and (b) AFM images of the F-GT / CB / PANI ink film and their corresponding potential distribution diagrams, and (c) and (d) AFM images of the F-GT / CB / PANI ink film and their corresponding height distribution diagrams. Figure 3 (a) It can be seen that the potential diagram is relatively uniform, indicating that the high-speed dispersion and ball milling processes were very successful. The three components achieved highly uniform mixing at the nanoscale, laying a solid foundation for the formation of an excellent conductive network. Next, specific potential diagram data processing was performed as follows: Figure 3 (b) It can be seen that it is highly consistent with the AFM image, the potential distribution is uniform, the filler is well dispersed, there is no serious agglomeration or phase separation, and a highly efficient and uniform conductive network is formed.

[0045] Figure 3The performance characterization diagram of the conductive ink in Example 1 is shown in (a). As the shear rate increases, the viscosity of the ink decreases, exhibiting a decreasing trend with increasing shear force, demonstrating typical pseudoplastic behavior. This shear-thinning property allows the ink to pass smoothly through the mesh under shear force. After the squeegee is removed, the ink solidifies on the substrate to obtain a printed pattern. (f) Subsequently, complex images such as flowers, delicate stripes, and Chinese calligraphy were printed on it. The clear flower stamens, uniform lines, and Chinese characters reflect the high resolution and fineness of the patterns produced by the ink printing. (b) Sheet resistance diagrams of conductive inks with different proportions show that polyaniline does not contribute positively to the conductivity of the ink. Since the intrinsic conductivity of polyaniline is lower than that of graphite carbon black, its contribution to the construction of the composite conductive network is limited. On the contrary, the "conductive bridge" structure formed by the dense embedding of carbon black particles between graphite sheets effectively reduces the high contact resistance between graphene sheets. The addition of polyaniline greatly improves the capacitance performance of the microcapacitor, which is verified by the electrochemical performance of the subsequent planar microcapacitor. (c) Storage performance diagram of conductive ink shows that after 1 month of storage, the sheet resistance only increased by 27, which is due to the excellent formulation of the ink. (d) Flexibility test of ink film shows that the sheet resistance increased by 19% after 1000 bends. (e) Nanoindentation test shows that the strength of the material is enhanced after the addition of polyaniline, mainly because the addition of polyaniline fills the gaps between graphite carbon black.

[0046] like Figure 3 As shown in (a), the ink exhibits typical shear-thinning behavior, making it suitable for screen printing. Figure 3 (b) shows that although the intrinsic conductivity of polyaniline is lower than that of graphite and carbon black, the ink still maintains a good conductive network after its addition. AFM potential diagram ( Figure 2 This confirmed that the three components were uniformly mixed at the nanoscale with no obvious agglomeration.

[0047] 3. Electrochemical performance

[0048] Ink is printed onto a PET substrate using screen printing technology and assembled into an all-solid-state planar micro supercapacitor (MSC). Figure 4The electrochemical performance (ac) of the planar microcapacitor in Example 1 includes the CV test curve, GCD test curve, and impedance spectrum. After the addition of polyaniline, the CV coating curve significantly increased, the GCD discharge time significantly increased, and the slope of the EIS plot in the high-frequency region also increased, indicating that the ion transport pathway was expanded. The addition of polyaniline effectively improved the charge storage capacity of the planar MSC. The reason for this is that after dispersion and ball milling, the original multilayer graphite was successfully exfoliated into few-layer graphene sheets; carbon black (CB) particles were tightly anchored to the surface of the graphite sheets, forming an effective "conductive bridge" network, significantly reducing the contact resistance between the graphite sheets. Simultaneously, the ball milling process promoted the uniform dispersion of polyaniline (PANI) particles and significantly refined their particle size, greatly increasing the active sites available for pseudocapacitive reactions. It is noteworthy that the PANI composite process occurred simultaneously with the graphite exfoliation and delamination, resulting in a large number of PANI particles being uniformly embedded in the graphene sheet structure formed by printing and stacking. This composite structure is beneficial for the penetration of electrolyte ions.

[0049] like Figure 4 As shown, compared to the comparative example (F-GT / CB), the area enclosed by the CV curve of Example 1 (F-GT / CB / PANI) is significantly increased, and the GCD discharge time is greatly prolonged. Calculations based on the GCD curve show that at 0.05 mA cm⁻¹... -2 At the given current density, the areal capacitance of Example 1 reaches 95.8 mF cm⁻¹. -2 The control ratio was only 10.65 mF cm. -2 This indicates that the addition of polyaniline provides a large pseudocapacitance, improving energy storage performance by nearly 9 times. Simultaneously, the device exhibits a voltage rating of 13.73 µWh / cm². -2 High surface energy density and 0.025 mW / cm² -2 The surface power density greatly enhances the charge storage capacity of planar microcapacitors.

[0050] 4. Flexible and integrated applications

[0051] Figure 5 For Example 1, the flexibility and integration performance of the planar microcapacitor are shown in (a). The CV curves under different bending states almost overlap, indicating that the device has excellent mechanical flexibility and the ability to stably store charge under bending conditions. For F-GT / CB / PANI MSCs, a bending test of 1000 cycles was conducted with each 200 bending angles as one cycle. It was found that the capacitance retention rate could still reach 89.3% after 1000 bending cycles, as shown in Figure (d). Figures (b) and (c) are the CV curves of 0 and 1000 bending tests, respectively. It can be seen that the shape of the CV curve is well maintained, which fully demonstrates the excellent mechanical flexibility of the planar MSCs.

[0052] To explore the potential applications of MSCs, we further integrated multiple devices in different ways (series and parallel) and characterized their corresponding electrochemical performance plots (e) and (f). When the three devices were successfully connected in series, the operating voltage window widened from 1V to 3V, successfully lighting a small light bulb. Figure 6 This demonstrates its practical application potential. Meanwhile, the shape of the CV curve did not change significantly, and the area covered by the CV curve increased significantly after parallel connection, which is consistent with the GCD curve results. Under the same operating current density, its charge / discharge time increased to three times the original.

[0053] Example 2 (Formulation with low polyaniline content)

[0054] This embodiment provides a low-viscosity conductive ink suitable for printing fine patterns. The raw material composition is as follows: 28 parts conductive filler (including 20g graphite, 4g carbon black, and 4g polyaniline), 29 parts binder (containing 29g of waterborne polyurethane F0410), 39 parts solvent (containing 39g of deionized water), and 3 parts additives (including 1g of waterborne defoamer and 2g of carbon black dispersant).

[0055] The preparation process is exactly the same as in Example 1.

[0056] The ink prepared in this embodiment has low viscosity and good fluidity, making it suitable for inkjet printing or fine screen printing. The resulting coating is thin and has relatively good light transmittance.

[0057] Example 3 (Formulation with high polyaniline content)

[0058] This embodiment investigates the effect of increasing the proportion of polyaniline on energy storage performance. The raw material composition is as follows: 28.25 parts of conductive filler (including 17.750g of graphite, 3.5g of carbon black, and 7g of polyaniline, i.e., the ratio of the three is adjusted to 5:1:2), 25 parts of binder, 50 parts of solvent, and 5 parts of additives.

[0059] The preparation process is exactly the same as in Example 1.

[0060] In this embodiment, the proportion of polyaniline in the conductive filler was increased. It was found that there is a maximum value for the amount of polyaniline. When the ratio of the three is 5:1:2, the excessive amount of polyaniline not only makes it difficult to utilize the high conductivity framework of graphite carbon black, but also easily agglomerates, leading to a decrease in active sites. As a result, the energy storage performance changes with the increase of the ratio.

[0061] Performance test comparison

[0062] The inks prepared in Examples 1-3 and Comparative Example 1 were used to print test strips and micro supercapacitors under the same conditions, and their key performance indicators were tested. The results are shown in Table 1 below.

[0063] Table 1 Comparison of ink and device performance in various embodiments

[0064]

[0065] As shown in Table 1, Examples 2 and 3 demonstrate that the formulations described in this invention can produce conductive inks with satisfactory performance. A low polyaniline content (Example 2) is beneficial for conductivity and film formation. Comparing Examples 1 and 3, it is evident that increasing the proportion of polyaniline can improve the areal capacitance, but with the continuous increase of PANI content, significant excessive PANI coating and agglomeration occurred. This over-agglomerated structure not only hinders the high conductivity of the graphite / carbon black conductive framework but also limits the effective utilization of PANI pseudocapacitive properties, ultimately leading to impaired ion diffusion kinetics. Since the intrinsic conductivity of polyaniline is lower than that of graphite, it causes a slight increase in sheet resistance. This indicates that this invention can balance conductivity and energy storage performance according to actual needs by adjusting the ratio of the three components.

[0066] This invention constructs a three-dimensional structure of "carbon black, polyaniline-few-layer graphite flakes-carbon black, polyaniline" through a simple dispersion and ball milling process. Using inexpensive graphite, carbon black, and polyaniline as conductive fillers, and water and water-soluble components (binders and additives) as the liquid phase, a low-cost, high-stability, high-conductivity, excellent mechanical flexibility, and environmentally friendly ink is prepared. In this process, the graphite is dispersed at high speed, and the shear force generated by ball milling peels it into thinner few-layer graphite flakes. The addition of carbon black increases the ink viscosity while effectively preventing the agglomeration of the few-layer graphite flakes. The stirring and dispersion process ensures initial uniform mixing and dispersion of the ink components, followed by ball milling to achieve full and uniform mixing and dispersion. The carbon black adheres more uniformly to the few-layer graphite flakes, thereby improving the overall stability and conductivity of the ink material. Furthermore, the addition of polyaniline allows it to adhere between the graphite flake layers. Due to its high conductivity and controllable pseudocapacitive properties, it significantly enhances the energy storage performance of the capacitor. Then, by combining it with screen printing technology, ink can be printed to form electrodes with interdigitated structures, which can be assembled into all-solid-state flexible micro supercapacitors, thereby realizing energy storage and showing great potential in the field of flexible electronics.

[0067] In summary, the polyaniline conductive ink prepared by this invention achieves a perfect combination of the high conductivity of carbon materials and the high pseudocapacitive properties of polyaniline through a simple physical peeling and composite process, making it particularly suitable for the manufacture of high-performance flexible energy storage devices.

Claims

1. A polyaniline conductive ink, characterized in that, The raw materials, by weight, include: 10-30 parts of conductive filler; 18-30 parts of binder; 32-69 parts of solvent; and 3-8 parts of additives; wherein the conductive filler is composed of graphite, carbon black, and polyaniline.

2. The polyaniline conductive ink according to claim 1, characterized in that, In the conductive filler, the mass ratio of graphite to carbon black is (4.5-5.5):1, and the mass ratio of polyaniline to carbon black is 1:1 to 2:

1.

3. The polyaniline conductive ink according to claim 1, characterized in that, The graphite has an average particle size of 1000-3000 mesh; the carbon black has an average particle size of 10-18 nm; and the polyaniline has an average particle size of 15-20 nm.

4. The polyaniline conductive ink according to claim 1, characterized in that, The adhesive is waterborne polyurethane; the solvent is water; and the additives include at least two of waterborne defoamers, waterborne carbon black dispersants, sodium carboxymethyl cellulose, and ethylene glycol.

5. The polyaniline conductive ink according to claim 1, characterized in that, The raw materials, by weight, include: 25-30 parts conductive filler and 25-30 parts waterborne polyurethane adhesive. 35-55 parts water, 3-6 parts additives; the conductive filler is composed of graphite, carbon black and polyaniline.

6. A method for preparing polyaniline conductive ink according to any one of claims 1-5, characterized in that, The method includes the following steps: S1, mixing conductive filler, binder, additives and solvent, stirring and dispersing to obtain a preliminary mixed ink; S2, ball milling the preliminary mixed ink to obtain the polyaniline conductive ink.

7. The preparation method according to claim 6, characterized in that, In step S1, the stirring and dispersing speed is 1000-4000 r / min and the time is 4-6 h; in step S2, the ball milling speed is 300-1500 r / min and the time is 4-6 h.

8. The application of a polyaniline conductive ink as described in any one of claims 1-5 in the field of flexible electronics.

9. The application according to claim 8, characterized in that, The specific application involves printing the polyaniline conductive ink onto a substrate to prepare flexible circuits or electrodes.

10. The application according to claim 9, characterized in that, The substrate includes a paper substrate or a polyethylene terephthalate (PET) substrate; the post-printing process also includes a drying step at 25-180°C for 2-12 hours.

Images