CN113717632A

CN113717632A - Polyaniline micelle graphene composite material, electrode coating, working electrode and preparation method thereof

Info

Publication number: CN113717632A
Application number: CN202110904738.0A
Authority: CN
Inventors: 付宁宁; 戴忠晨; 罗瑞; 金文涛; 谢绍兴; 丁亚萍; 鲁万彪
Original assignee: CRRC Nanjing Puzhen Rail Transport Co Ltd
Current assignee: CRRC Nanjing Puzhen Rail Transport Co Ltd
Priority date: 2021-08-07
Filing date: 2021-08-07
Publication date: 2021-11-30

Abstract

The invention discloses a polyaniline micelle graphene composite material, an electrode coating, a working electrode and a preparation method thereof, belonging to the technical field of corrosion protection, and solving the problems that graphene is easy to agglomerate, polyaniline is difficult to dissolve in water, and the excellent properties of the two materials cannot be effectively utilized in the prior art. The graphene-based composite material comprises an aqueous polyvinyl alcohol-polyaniline micelle and graphene; the composite material has the advantages that pi-pi bonds which are beneficial to inhibiting graphene agglomeration are formed between the graphene and the aqueous polyvinyl alcohol-polyaniline micelles, the aqueous polyvinyl alcohol-polyaniline micelles are used as components of the composite material, so that the composite material has high conductivity and corrosion resistance of polyaniline, the problem that the polyaniline is difficult to dissolve in water is solved, the composite material is formed, the composite material has excellent blocking and shielding properties of the graphene, the working electrode has better corrosion resistance, and the technical problem that the graphene is easy to agglomerate is solved through the pi-pi action between the aqueous polyvinyl alcohol-polyaniline micelles and the graphene.

Description

Polyaniline micelle graphene composite material, electrode coating, working electrode and preparation method thereof

Technical Field

The invention relates to a polyaniline micelle graphene composite material, an electrode coating, a working electrode and a preparation method thereof, and belongs to the technical field of corrosion protection.

Background

Corrosion protection plays a very important role in the modern metal surface treatment industry, and one of the most effective ways to protect metals from corrosion is to apply an anticorrosive coating on its surface. The organic solvent type coating is one of common anticorrosive materials in practical production application, but the generated volatile organic compounds not only pollute the environment, but also bring harm to human bodies. Therefore, there is a need to develop a new environment-friendly coating, which has both excellent corrosion resistance and environmental friendliness.

Although polyaniline is reported in anticorrosive coatings, polyaniline has a problem of difficult dissolution, and can only be partially dissolved in Dimethylformamide (DMF) and methylpyrrolidone (NMP), which greatly limits the application of polyaniline, the use of toxic solvents can bring serious pollution problems to the environment and threaten the safety of human beings, and although graphene shows excellent anticorrosive performance, strong pi-pi bond action exists between graphene sheet layers, which causes that graphene is easy to agglomerate, and the application of graphene in the anticorrosive field is also greatly limited.

In view of this, the invention is particularly proposed.

Disclosure of Invention

The invention aims to overcome the defects in the prior art and provides a polyaniline micelle graphene composite material, an electrode coating, a working electrode and a preparation method thereof.

In order to achieve the above purpose/to solve the above technical problems, the present invention is realized by adopting the following technical scheme:

a polyaniline micelle graphene composite material comprises aqueous polyvinyl alcohol-polyaniline micelles and graphene;

and a pi-pi bond which is beneficial to inhibiting graphene agglomeration is formed between the graphene and the aqueous polyvinyl alcohol-polyaniline micelle.

The invention also provides a preparation method of the polyaniline micelle graphene composite material, which comprises the following steps:

A. preparing polyvinyl alcohol solution and treating aniline;

B. mixing a polyvinyl alcohol solution and an aniline monomer to prepare an aqueous polyvinyl alcohol-polyaniline micelle;

C. dissolving the aqueous polyvinyl alcohol-polyaniline micelle in the B in water, and mixing with graphene;

D. and (4) carrying out ultrasonic dispersion on the mixture in the C to prepare the P/PANI-G composite material.

Preferably, the aqueous polyvinyl alcohol-polyaniline micelle is prepared, and the mass ratio of the polyvinyl alcohol to the aniline monomer is 1: 1-2.

Preferably, the mass ratio of the aqueous polyvinyl alcohol-polyaniline micelle to the graphene is 1-1.1: 2.

Preferably, the mass ratio of the aqueous polyvinyl alcohol-polyaniline micelle to the graphene is 1: 2.

Preferably, the power adopted by the ultrasonic dispersion is 800-900W; the ultrasonic treatment time is 100-120 min.

The invention also provides a composite material, which comprises the polyaniline micelle graphene composite material, epoxy resin and an epoxy resin curing agent, wherein the mass ratio of the polyaniline micelle graphene composite material to the polyaniline micelle graphene composite material is 0.3-0.5%, and the mass ratio of the epoxy resin to the polyaniline micelle graphene composite material is 30-33.17%;

the mass ratio of the epoxy resin curing agent to the composite material is 66.33-69.7%.

Preferably, the mass ratio of the polyaniline micelle graphene composite material to the composite material is 0.5%.

The invention also provides an electrode coating which comprises the composite material.

The invention also provides a working electrode, which comprises a substrate and the coating, wherein the coating is the electrode coating;

preferably, the substrate is made of steel, and the thickness of the coating is 0.1-100 mm.

Compared with the prior art, the invention has the following beneficial effects:

the polyaniline micelle graphene composite material adopts the aqueous polyvinyl alcohol-polyaniline micelle as a component of the composite material, so that the composite material has the high conductivity and the corrosion resistance of polyaniline, and also solves the problem that polyaniline is difficult to dissolve in water.

Drawings

FIG. 1 is a flow chart of preparation of the polyaniline micelle graphene composite material and a physical photograph of G and P/PANi-G after standing for 24 hours;

FIG. 2 is a flow chart of the preparation of the composite material provided by the present invention;

FIG. 3 is an SEM photograph of G, P/PANI and P/PANI-G provided by the present invention;

FIG. 4 is an SEM photograph of a brittle section of a coating provided by the present invention;

FIG. 5 shows Bode diagrams of P/PANI-G-0.3%, P/PANI-G-0.5% and P/PANI-G-0.7% Q235 steel of the present invention immersed in 3.5% NaCl solution continuously for 7 days ((a), (a ') pure epoxy resin, (b), (b') P/PANI-G-0.3%, (c), (c ') P/PANI-G-0.5% and (d), (d') P/PANI-G-0.7%);

FIG. 6 is a Bode plot of P/PANI-0.5% and G-0.5% coated Q235 steels of the present invention after 7 days soaking in 3.5% NaCl solution ((a), (a ') P/PANI-0.5%; (b), (b') G-0.5%);

FIG. 7 is a zeta potential polarization curve diagram of the bare steel Q235, pure epoxy resin, CSA/PANI-G-0.3%, CSA/PANI-G-0.5%, CSA/PANI-G-0.7% provided by the present invention;

FIG. 8 is a diagram of the corrosion protection mechanism of P/PANI-G/Epoxy provided by the present invention ((a) pure Epoxy coating, (b) P/PANI-G composite coating);

FIG. 9 is a table of coating potentiodynamic polarization parameter values provided by the present invention.

Detailed Description

The invention is further described below with reference to the accompanying drawings. The following examples are only for illustrating the technical solutions of the present invention more clearly, and the protection scope of the present invention is not limited thereby.

A. preparing polyvinyl alcohol solution and treating aniline;

Wherein: firstly, distilling aniline under reduced pressure, and then storing aniline in a refrigerating chamber of a refrigerator in a dark place for later use;

next, 1g of polyvinyl alcohol (polymerization degree: 1788) was dissolved in 150mL of 1M HCl and stirred at 60 ℃ to prepare a polyvinyl alcohol (PVA) solution. Then 2g of distilled aniline monomer was added to the above solution and stirred under ice bath conditions (0-5 ℃ C.) for 60 min. Marking as A solution; then, a hydrochloric acid (1M) solution of 50mLAPS is prepared, and the mass ratio of APS to ANi (aniline) is 1: 1.25. marking as a solution B; the solution B was then added dropwise to the solution a over an hour. Mechanically stirring (rotation speed 200rpm) under ice bath conditions (0-5 ℃) and keeping for 24 hours. Finally, obtaining a dark green colloidal dispersion (with the volume of 200 mL), obtaining dark green polyvinyl alcohol-polyaniline micelles (P/PANi) by centrifuging at 12000rpm for 20min, and repeatedly washing with deionized water and absolute ethyl alcohol to ensure that inorganic salts are completely removed; and finally, putting the obtained P/PANI colloid into a freeze dryer for freeze drying for 48 hours to obtain dry P/PANI colloid powder, and collecting for later use.

The mass ratio of the aqueous polyvinyl alcohol-polyaniline micelle to the graphene is 1-1.1:2, and the mass ratio of the aqueous polyvinyl alcohol-polyaniline micelle to the graphene is preferably 1: 2.

Preparing aqueous polyvinyl alcohol-polyaniline micelles, wherein the mass ratio of polyvinyl alcohol to aniline monomers is 1:1-2, specifically, weighing 125mg of freeze-dried P/PANI colloidal powder, dissolving the powder in 50mL of deionized water, then adding 250mg of graphene (G) into the aqueous solution of P/PANI, and performing ultrasonic dispersion treatment, wherein the ultrasonic power is 800W and the ultrasonic time is 120min, so as to obtain a polyaniline micelle graphene composite material which is marked as a P/PANI-G composite material, the reaction flow for preparing the P/PANI-G composite material is shown in a left diagram in fig. 1, and a real object diagram of the prepared P/PANI-G composite material after standing for 24h and a real object diagram of pure graphene are shown in a right diagram in fig. 1.

And observing the micro-morphology of the prepared aqueous polyvinyl alcohol-polyaniline micelle (P/PANI colloidal powder), polyaniline micelle graphene composite material (P/PANI-G composite material) and graphene by adopting SEM.

The SEM image is shown in fig. 3, wherein a in fig. 3 is an SEM electron micrograph of graphene, and it can be seen that graphene has a size of about 15 μm, a relatively regular surface, no defects such as voids, and potential for blocking corrosive media such as H2O molecules, O2 molecules, and Cl "ions. FIG. 3 b is an SEM image of the colloidal powder of P/PANI, which shows that P/PANI is spherical, has a diameter of about 80nm, and has uniform particle size. FIG. 3 c is an SEM image of the P/PANI-G composite material, and referring to FIG. 3 c, when P/PANI and G are subjected to ultrasonic treatment, it is found that P/PANI is tightly supported on the surface of G.

the mass ratio of the epoxy resin curing agent in the composite material is 66.33-69.7%.

The mass ratio of the polyaniline micelle graphene composite material to the composite material is 0.5%.

Firstly, adding 10g of epoxy resin curing agent H228B into a triangular flask, and stirring while vacuumizing (the rotating speed is 500rpm, and the time is 10min) until all bubbles in the curing agent are removed; then measuring 10mL of the P/PANi-G aqueous solution, adding the aqueous solution into 10G of epoxy resin curing agent, and continuously vacuumizing and stirring to obtain a mixture (the rotating speed is 500rpm, and the time is 30 min); finally, 5G of epoxy resin H228A was weighed into the above mixture, and the mixture was further evacuated and stirred (500 rpm for 15 min) to obtain a composite material, which was recorded as PANI-G-0.5%, and the preparation scheme is shown in FIG. 2.

The invention also provides an electrode coating, which comprises the composite material, according to the preparation method, the proportion of G and PANI is kept to be 2:1, 6mL and 14mL of the P/PANI-G aqueous solution are respectively measured and added into 10G of epoxy resin curing agent, and the mixture is prepared by continuously vacuumizing and stirring (the rotating speed is 500rpm and the time is 30 min); finally, 5G of epoxy resin H228A is weighed and added into the mixture, the mixture is continuously vacuumized and stirred (the rotating speed is 500rpm, the time is 15 min), and composite coatings with the contents of PANI-G-0.3 percent and PANI-G-0.7 percent are correspondingly and respectively prepared.

The test was carried out:

(1) preparing composite coatings with different P/PANI-G contents according to the preparation method of the composite material, and respectively adding the P/PANI-G into a water-based Epoxy resin matrix (Epoxy) according to the mass fraction ratios of 0.3wt%, 0.5wt% and 0.7wt% for magnetic stirring to obtain the P/PANI-G/Epoxy composite anticorrosive coating (abbreviated as P/PANI-G-x, wherein x represents the mass fraction of P/PANI-G). Meanwhile, for comparison, 0.5wt% of P/PANI and G are respectively added into the waterborne Epoxy resin to obtain P/PANI/Epoxy and G/Epoxy composite coatings, which are respectively marked as P/PANI-0.5% and G-0.5%.

Before observing the section, all samples are immersed in liquid nitrogen for 20min, and then the brittle section SEM observation of the sample coating is carried out. The observation results are shown in FIG. 4, wherein the a diagram in FIG. 4 is an SEM diagram of pure epoxy resin, the b diagram in FIG. 4 is an SEM diagram of P/PANI-0.5%, the c diagram in FIG. 4 is an SEM diagram of G-0.5%, the d diagram in FIG. 4 is an SEM diagram of P/PANI-G-0.3%, the e diagram in FIG. 4 is an SEM diagram of P/PANI-G-0.5%, and the f diagram in FIG. 4 is an SEM diagram of P/PANI-G-0.7%. As can be seen from the graph a in FIG. 4, the cross section of the pure epoxy resin is relatively flat and the roughness is very low; this is because epoxy resins are highly crosslinked thermosetting coatings that result in low fracture toughness due to their low plastic deformation caused by cracking resistance.

When 0.5% of P/PANI is added to the pure water-based epoxy resin, as shown in the b diagram in FIG. 4, the brittle fracture surface is rough compared with the pure epoxy resin, the crack length is short compared with the pure epoxy resin, and the P/PANI plays a role in increasing the crosslink density during the curing of the epoxy resin.

The addition of 0.5wt% of G to the aqueous epoxy resin, as shown in the c diagram in FIG. 4, shows that many pores are clearly seen at the cross section, and the cross section is very rough, which is analyzed to be the generation of many pores at the cross section due to the uneven dispersion of graphene in the epoxy resin.

When the amount of P/PANI-G added is 0.3wt%, it can be seen from the d-diagram in FIG. 4 that P/PANI-G is dispersed in the epoxy resin matrix more uniformly and the fracture surface is slightly rough compared with the pure epoxy resin in the a-diagram in FIG. 4.

When the amount of P/PANI-G added was 0.5wt%, many projections were observed on the fracture surface, and it can be seen from the graph e in FIG. 4 that the fracture surface had sparse and smooth cracks and no holes were formed, which is associated with good dispersion of P/PANI-G in the epoxy group.

When the addition amount of P/PANI-G is 0.7wt%, referring to the f diagram in FIG. 4, it can be seen that the P/PANI-G is seriously agglomerated in the epoxy resin due to the excessive addition amount of P/PANI-G, and more pores and disordered cracks are formed on the cross section of the composite coating. That is, when the amount of P/PANi-G added is 0.7wt%, the corrosive medium more easily permeates through pores and disordered cracks, and corrodes metals, meaning that it has poor corrosion prevention properties.

(2) Electrochemical Impedance Spectroscopy (EIS) technique determines the protective properties of a coating on a metal substrate by testing the impedance modulus of the coating, wherein Bode plot is a common mode in EIS spectra. The Bode plot can be divided into two regions in corrosive solutions: a high frequency region of 101Hz to 105Hz and a low frequency region of less than 101 Hz. In general, the impedance modulus at the lowest frequency (f =0.01 Hz) in the Bode plot can be used as a semi-quantitative indicator of the barrier performance of the coating. In the experiment, the anticorrosive performance of the pure epoxy resin, P/PANI-G-0.3%, P/PANI-G-0.5% and P/PANI-G-0.7% coating samples in the experiment (1) is detected.

FIG. 5 is a Bode plot of pure epoxy, P/PANI-G-0.3%, P/PANI-G-0.5%, and P/PANI-G-0.7% coated samples immersed in 3.5% NaCl solution for 7 consecutive days. As can be seen from a diagram in fig. 5, the impedance modulus of the pure epoxy resin at f =0.01Hz is about 1.25 × 105 Ω cm2 after soaking in 3.5% NaCl solution for 1 day, and the impedance modulus of the pure epoxy resin at f =0.01Hz gradually decreases with the increase of the soaking time. After 7 days of continuous soaking, the impedance modulus of the neat epoxy at f =0.01Hz decreased significantly by about two orders of magnitude, being 3.98 × 103 Ω cm 2.

Referring to b in fig. 5, for the composite coating obtained by adding 0.3wt% of P/PANi to the water-based epoxy resin, the impedance modulus of the composite coating P/PANi-0.3% at f =0.01Hz after soaking for 1 day is 1.26 × 106 Ω cm2, which is significantly higher than that of the pure epoxy resin.

As the content of P/PANI-G increases to 0.5wt% and 0.7wt%, refer to graphs c and d in FIG. 5. The modulus resistance values of the P/PANi-G-0.5% and P/PANi-G-0.7% composite coatings at f =0.01Hz after soaking in 3.5% NaCl solution for 24h were 3.17 × 106 and 5.01 × 105 Ω cm2, respectively. With the immersion time extended to 7 days, the impedance modulus at f =0.01Hz of P/PANi-G-0.3%, P/PANi-G-0.5% and P/PANi-G-0.7% decreased, specifically 2.51 × 104, 1.26 × 105 and 3.16 × 104 Ω cm2, respectively, which were higher than the impedance modulus after the pure epoxy resin was immersed for 7 days. By comparison, the impedance modulus of the P/PANi-G-0.5% sample at f =0.01Hz is an order of magnitude higher than the other samples, indicating that the addition of 0.5% P/PANi-G-to the epoxy resin has the best protective properties for Q235 steel. Too much P/PANi-G content may result in uneven dispersion in the epoxy resin, resulting in poor barrier properties, and too low a content may not form an effective barrier layer.

In addition, high frequency phase angle can also be an effective parameter for evaluating the protective performance of the coating. In the case of high resistance coatings, current preferentially passes through the dielectric path, resulting in a higher phase angle between current and voltage. Referring to a ' diagram, a c ' diagram and a d ' diagram in fig. 5, the anticorrosive coating obtained by adding 0.5% of P/PANI-G into the epoxy resin has a phase angle (-80 ℃) in a high-frequency region which is obviously higher than the values of anticorrosive coatings of other P/PANI-G.

From the test results in this experiment, it can be preliminarily determined that the sample coated with the P/PANI-G-0.5% composite coating has higher impedance value and phase angle than other coatings, indicating that the coating has better protective performance for the metal substrate.

(3) In correspondence with experiment (2), P/PANI and G were added to the epoxy resin in a mass fraction of 0.5wt%, respectively. The resulting samples were designated P/PANI-0.5% and G-0.5%, respectively. FIG. 6 is a Bode plot of P/PANi-0.5% and G-0.5%. As can be seen from the a-and b-plots in FIG. 6, the impedance moduli of P/PANi-0.5% and G-0.5% at f =0.01Hz were 5.62X 105 and 1.77X 105. omega. cm2, respectively, both higher than the impedance value of the initial stage of the pure epoxy resin in Experimental example 3 but lower than the impedance modulus of P/PANi-G-0.5% in Experimental example 3. The impedance modulus of P/PANi-0.5% and G-0.5% at f =0.01Hz remained at a high level after 7 days soaking in 3.5% NaCl solution, indicating that the 0.5% content contributes to the improvement of the corrosion resistance of the waterborne epoxy resin.

As can be seen from the graphs a 'and b' in FIG. 6, the phase angle of G-0.5% in the high frequency region is low.

(4) Potentiodynamic polarization curves of the different coatings immersed in 3.5 wt% NaCl solution are shown with reference to FIG. 7. Generally, the corrosion potential (Ecorr) mainly represents the tendency of corrosion reaction, and the higher the corrosion potential, the lower the corrosion current density, which indicates the better corrosion prevention effect of the coating.

As is apparent from fig. 7, after the Q235 steel was coated with the paint, the corrosion potential was clearly shifted to the high potential direction. For bare steel, pure epoxy resin, P/PANi-0.3%, P/PANi-G-0.5% and P/PANi-G-0.7%, the corrosion potentials are-0.75, -0.39, -0.25, -0.22 and-0.30V, respectively. Therefore, when the P/PANI-G is added in an amount of 0.5wt%, the corrosion potential is highest, which means that the corrosion resistance is the best.

Further, according to faraday's law, corrosion current density (Icorr) and corrosion rate are in a positive correlation, and thus, a lower value of Icorr decreases the corrosion rate. Wherein the corrosion current density of P/PANI-G-0.5% is the lowest, which is 2.53 multiplied by 10 < -7 > Acm < -2 >, and the protection efficiency on Q235 steel is 99.38%. The current densities and protective efficiencies of the protective efficiency coatings for Q235 for the other samples are shown in table 1. By combining the results of corrosion potential and corrosion current density analysis, it can be seen that P/PANI-G-0.5% shows excellent corrosion resistance in the prepared sample.

The corrosion prevention mechanism of P/PANI-G/Epoxy is shown in a and b of FIG. 8. The PANI can generate oxidation-reduction reaction with iron at an interface to generate Fe-NH complex, and the complex has higher oxidation potential and can compensate charge consumed by dissolution of the iron, so that the potential of the iron is stabilized in a passivation region. Meanwhile, the graphene which is overlapped layer by layer and staggered can be uniformly dispersed in the water-based epoxy resin to form a structure like a labyrinth, and due to the blocking effect of the graphene, the anti-permeation effect of the epoxy resin on corrosive media such as H2O, O2 and Cl & lt- & gt is greatly enhanced, and the path of the corrosive media entering the Q235 steel substrate can be prolonged. In addition, due to the small size effect of graphene, graphene can fill the defects of epoxy resin, and the number of defects such as voids is reduced. Therefore, the P/PANI-G/epoxy composite coating prepared by integrating the excellent characteristics of polyaniline and graphene has excellent corrosion resistance.

the substrate is made of steel, and the thickness of the coating is 0.1-100 mm.

Wherein, Q235 steel blocks with the thickness of 20mm multiplied by 5mm are sequentially polished by sandpaper with 80, 200, 400, 600, 800 and 1000 meshes, and are put into absolute ethyl alcohol and acetone for alternative ultrasonic treatment (power 100W, time 30min) to remove dirt and grease on the surface of the steel; putting the processed steel block into an oven for drying; and respectively spin-coating the suspensions with different P/PANI-G contents on the surfaces of a plurality of pretreated Q235 steel of the same batch, and curing for 72 hours at room temperature to obtain the working electrodes coated with different P/PANI-G contents.

In addition, a pure epoxy resin coating is coated on the surface of the pretreated Q235 steel in the same treatment mode, and the working electrode coated with the pure epoxy resin coating is obtained.

The above is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, several modifications and variations can be made without departing from the technical principle of the present invention, and these modifications and variations should also be regarded as the protection scope of the present invention.

Claims

1. A polyaniline micelle graphene composite material is characterized by comprising aqueous polyvinyl alcohol-polyaniline micelles and graphene;

2. The method for preparing the polyaniline micelle graphene composite material as claimed in claim 1, comprising the following steps:

preparing polyvinyl alcohol solution and treating aniline;

mixing a polyvinyl alcohol solution and an aniline monomer to prepare an aqueous polyvinyl alcohol-polyaniline micelle;

dissolving the aqueous polyvinyl alcohol-polyaniline micelle in the B in water, and mixing with graphene;

and (4) carrying out ultrasonic dispersion on the mixture in the C to prepare the P/PANI-G composite material.

3. The method for preparing the polyaniline micelle graphene composite material according to claim 2, wherein the mass ratio of the polyvinyl alcohol to the aniline monomer for preparing the aqueous polyvinyl alcohol-polyaniline micelle is 1: 1-2.

4. The method for preparing the polyaniline micelle graphene composite material as claimed in claim 2, wherein the mass ratio of the aqueous polyvinyl alcohol-polyaniline micelle to the graphene is 1-1.1: 2.

5. The method for preparing the polyaniline micelle graphene composite material as claimed in claim 4, wherein the mass ratio of the aqueous polyvinyl alcohol-polyaniline micelle to the graphene is 1: 2.

6. The method for preparing the polyaniline micelle graphene composite material as claimed in claim 2, wherein the power of ultrasound used for the ultrasonic dispersion is 800-900W; the ultrasonic treatment time is 100-120 min.

7. A composite material, which is characterized by comprising the polyaniline micelle graphene composite material, epoxy resin and an epoxy resin curing agent according to claim 1, wherein the mass ratio of the polyaniline micelle graphene composite material to the polyaniline micelle graphene composite material is 0.3-0.5%, and the mass ratio of the epoxy resin to the polyaniline micelle graphene composite material is 30-33.17%;

8. The composite material according to claim 7, wherein the mass ratio of the polyaniline micelle graphene composite material to the composite material is 0.5%.

9. An electrode coating material comprising the composite material according to any one of claims 7 to 8.

10. A working electrode comprising a substrate and a coating, said coating being the electrode coating of claim 9;

the substrate is made of steel, and the thickness of the coating is 0.1-100 mm.