阅读说明：本技术 石墨烯接枝聚合物电极材料的制备方法及其用途 (Preparation method and application of graphene grafted polymer electrode material ) 是由 赵瑨云 胡家朋 林皓 梁松 张玉斌 林志毅 于 2021-08-23 设计创作，主要内容包括：本发明提供了一种石墨烯接枝聚合物电极材料的制备方法。其包括如下步骤：氮掺杂氧化石墨烯的制备、二异氰酸酯改性氮掺杂氧化石墨烯的制备、氮掺杂氧化石墨烯接枝聚苯胺-co-对苯二胺的制备、氮掺杂氧化石墨烯接枝聚苯胺-co-对苯二胺/MnO-(2)的制备、石墨烯接枝聚合物电极材料的制备。该制备方法工艺稳定、易于操作、质量可靠、成本低廉,质量轻,无污染等特点,具有很好的商业化前景。(The invention provides a preparation method of a graphene grafted polymer electrode material. Which comprises the following steps: preparation of nitrogen-doped graphene oxide, preparation of diisocyanate-modified nitrogen-doped graphene oxide, preparation of nitrogen-doped graphene oxide grafted polyaniline-co-p-phenylenediamine, and preparation of nitrogen-doped graphene oxide grafted polyaniline-co-p-phenylenediamine/MnO 2 And preparing the graphene grafted polymer electrode material. The preparation method has the characteristics of stable process, easiness in operation, reliable quality, low cost, light weight, no pollution and the like, and has good commercial prospect.)

1. A preparation method of a graphene grafted polymer electrode material is characterized by comprising the following steps:

preparing nitrogen-doped graphene oxide;

activating the doped graphene oxide by using a mixed solution of sulfuric acid and nitric acid to obtain activated doped graphene oxide, and performing reflux reaction on the activated doped graphene oxide and toluene-2, 4-diisocyanate at 55-60 ℃ to obtain diisocyanate modified nitrogen-doped graphene oxide;

uniformly mixing the diisocyanate modified nitrogen-doped graphene oxide with aniline and p-phenylenediamine, and carrying out copolymerization reaction under the initiation of ammonium persulfate to obtain nitrogen-doped graphene oxide grafted polyaniline-co-p-phenylenediamine;

dissolving cetyl trimethyl ammonium bromide, ethanol and manganese nitrate in deionized water, adding the nitrogen-doped graphene oxide grafted polyaniline-co-p-phenylenediamine, stirring to obtain a dispersion solution, dropwise adding a potassium permanganate aqueous solution into the dispersion solution, and reacting at normal temperature to obtain the nitrogen-doped graphene oxide grafted polyaniline-co-p-phenylenediamine/MnO₂Namely the graphene grafted polymer electrode material.

2. The method for preparing the graphene grafted polymer electrode material according to claim 1, wherein the method for preparing the nitrogen-doped graphene oxide comprises the following steps:

dispersing graphene oxide and sodium dodecyl benzene sulfonate in deionized water, and adding pyrrole and FeC1₃Reacting to obtain a graphene oxide/polypyrrole compound;

and soaking the graphene oxide/polypyrrole compound in an ammonium chloride solution, washing, drying, heating from 25 ℃ to 250-300 ℃ under the protection of argon, preserving heat for 2 hours, heating from 250-300 ℃ to 750-800 ℃, and preserving heat for 2 hours to obtain the nitrogen-doped graphene oxide.

3. The method for preparing the graphene grafted polymer electrode material according to claim 2, wherein the mass concentration of the ammonium chloride solution is 0.5-1%.

4. The preparation method of the graphene grafted polymer electrode material according to claim 2, wherein the mass ratio of the graphene oxide to the pyrrole is (5-10): (1-2).

5. The preparation method of the graphene grafted polymer electrode material according to claim 1, wherein the mass ratio of the activated nitrogen-doped graphene oxide to toluene-2, 4-diisocyanate is (1-3): (3-5), wherein the mass ratio of the aniline to the p-phenylenediamine is (5-10): (1-2).

6. The method for preparing the graphene grafted polymer electrode material according to claim 1, wherein the temperature of the copolymerization reaction is 0-5 ℃.

7. A graphene grafted polymer electrode material obtained by the preparation method of claim 1.

8. A preparation method of an electrode is characterized by comprising the following steps:

mixing the graphene grafted polymer electrode material according to claim 7, acetylene black and PTFE in a ratio of 8: 1: dispersing the powder in absolute ethyl alcohol according to the mass ratio of 1, coating fluorine on the surface of foamed nickel, drying in vacuum, and tabletting under the pressure of 10MPa to obtain the nitrogen-doped graphene oxide grafted polyaniline-co-p-phenylenediamine/MnO₂And an electrode.

9. Use of the electrode obtained by the preparation method according to claim 7 in a supercapacitor.

Technical Field

The invention relates to a preparation method of a graphene grafted polymer electrode material, belonging to the field of composite materials and electrochemical materials.

Background

With the rapid development of human society, the shortage of non-renewable energy becomes a problem which needs to be solved urgently by human beings. The development of new renewable energy sources has become a hotspot of scientific research at present. Electrochemical energy storage is highly appreciated by scientists because it is continuously reliable. The super capacitor is a novel energy storage device between a traditional capacitor and a rechargeable battery, and has been widely applied to the fields of traffic, information technology, power equipment, communication and the like due to the characteristics of high power density, high energy density, high charge-discharge rate, green environmental protection and the like. However, a key factor determining the performance of supercapacitors is the choice of electrode material. The electrode material is selected to have good conductivity, large specific surface area and high specific capacitance. For the reasons, carbon materials, metal compounds and conductive polymers are mainly selected as electrode materials of the current super capacitor.

Graphene (Graphene) is sp²The hybridized and connected carbon atoms are tightly packed into a new material with a single-layer two-dimensional honeycomb lattice structure. It has excellent properties such as high specific surface area, good thermal and electrical conductivity, adjustable structure and specific surface area, short diffusion distance (mainly due to thin thickness), good chemical stability, and high mechanical strength. Besides, it also has the advantages of large single-layer surface area and open pore structure, etc. At present, graphene has been applied to lithium ion batteries, supercapacitors, electrode materials of solar batteries, hydrogen storage materials and solar batteriesSensors, optical materials, drug carriers, etc. Zhang et al reduced graphene oxide with L-ascorbic acid as a reducing agent, and then prepared graphene aerogel by freeze-drying and supercritical drying, which showed high mechanical strength and high conductivity. As an electrode material of a super capacitor, the specific capacitance reaches 128F/g. The aerogel can bear 14000 times its own weight, which is 2 times that of carbon nanotubes (Zhang X, et al, mechanical strength and high purity conductive graphene aerogel and its use as electrodes for electrochemical power sources j. mater. chem., 2011,21, 6494). How to further improve the specific capacitance of the electrode material of the graphene supercapacitor becomes a hot spot of scientific research.

The invention content is as follows:

the invention aims to provide a preparation method and application of a graphene grafted polymer electrode material, so as to solve the problems in the prior art.

In order to achieve the purpose, the technical scheme of the invention is as follows:

a preparation method of a graphene grafted polymer electrode material comprises the following steps:

preparing nitrogen-doped graphene oxide;

activating the doped graphene oxide by using a mixed solution of sulfuric acid and nitric acid to obtain activated doped graphene oxide, and performing reflux reaction on the activated doped graphene oxide and toluene-2, 4-diisocyanate at 55-60 ℃ to obtain diisocyanate modified nitrogen-doped graphene oxide;

uniformly mixing the diisocyanate modified nitrogen-doped graphene oxide with aniline and p-phenylenediamine, and then carrying out copolymerization reaction under the initiation of ammonium persulfate to obtain nitrogen-doped graphene oxide grafted polyaniline-co-p-phenylenediamine;

dissolving cetyl trimethyl ammonium bromide, ethanol and manganese nitrate in deionized water, adding the nitrogen-doped graphene oxide grafted polyaniline-co-p-phenylenediamine, stirring to obtain a dispersion solution, dropwise adding a potassium permanganate aqueous solution into the dispersion solution, and reacting at normal temperature to obtain the nitrogen-doped graphene oxide grafted polyaniline-co-p-phenylenediamine/MnO₂Namely the graphene grafted polymer electrode material.

As a preferred scheme, the preparation method of the nitrogen-doped graphene oxide comprises the following steps:

dispersing graphene oxide and sodium dodecyl benzene sulfonate in deionized water, and adding pyrrole and FeC1₃Reacting to obtain a graphene oxide/polypyrrole compound;

and soaking the graphene oxide/polypyrrole compound in an ammonium chloride solution, washing, drying, heating from 25 ℃ to 250-300 ℃ under the protection of argon, preserving heat for 2 hours, heating from 250-300 ℃ to 750-800 ℃, and preserving heat for 2 hours to obtain the nitrogen-doped graphene oxide.

Preferably, the mass concentration of the ammonium chloride solution is 0.5-1%.

Preferably, the mass ratio of the graphene oxide to the pyrrole is (5-10): (1-2).

Preferably, the mass ratio of the activated nitrogen-doped graphene oxide to the toluene-2, 4-diisocyanate is (1-3): (3-5), wherein the mass ratio of the aniline to the p-phenylenediamine is (5-10): (1-2).

Preferably, the temperature of the copolymerization reaction is 0-5 ℃.

The graphene grafted polymer electrode material prepared by the preparation method.

A method of making an electrode comprising the steps of:

mixing the graphene grafted polymer electrode material, acetylene black and PTFE according to the weight ratio of 8: 1: dispersing the powder in absolute ethyl alcohol according to the mass ratio of 1, coating fluorine on the surface of foamed nickel, drying in vacuum, and tabletting under the pressure of 10MPa to obtain the nitrogen-doped graphene oxide grafted polyaniline-co-p-phenylenediamine/MnO₂And an electrode.

Use of an electrode obtained by the preparation method in a supercapacitor.

The mechanism of the invention is as follows:

1) firstly, graphene oxide is used as a carrier, sodium dodecyl benzene sulfonate is used as a surfactant, ferric trichloride is used as an oxidation initiator, more active functional groups are contained on the surface of the graphene oxide, and pyrrole monomer polymerization is initiated in an aqueous solution system to obtain the graphene oxide/polypyrrole composite material. And under the condition that the polypyrrole provides a nitrogen source, activating, pre-oxidizing and carbonizing the composite material by using ammonium chloride to obtain the nitrogen-doped graphene oxide.

2) Activating nitrogen-doped graphene oxide by using a mixed solution of sulfuric acid and nitric acid, and then reacting the activated nitrogen-doped graphene oxide with toluene-2, 4-diisocyanate to obtain diisocyanate modified nitrogen-doped graphene oxide. And (3) carrying out graft copolymerization on diisocyanate modified nitrogen-doped graphene oxide, aniline and p-diphenylamine by using ammonium persulfate as an initiator to obtain the nitrogen-doped graphene oxide grafted polyaniline-co-p-phenylenediamine.

3) The nitrogen-doped graphene oxide grafted polyaniline-co-p-phenylenediamine/MnO is obtained by taking nitrogen-doped graphene oxide grafted polyaniline-co-p-phenylenediamine as a carrier, and carrying manganese dioxide obtained by redox reaction of manganese nitrate and potassium permanganate on the carrier₂。

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

1) the nitrogen-doped graphene oxide grafted polymer electrode material improves the wettability between an electrolyte and an electrode by utilizing the high porosity and the large specific surface area of graphene oxide.

2) The polyaniline-co-p-phenylenediamine is grafted on the nitrogen-doped graphene electrode, so that the defect of low specific capacitance of a single graphene electrode material is overcome, and the specific capacitance of the electrode material is greatly improved.

3) Compared with graphene oxide, the doping of nitrogen element in the nitrogen-doped graphene oxide can generate N-C bonds, wherein C atoms adjacent to N atoms can carry more positive charges, so that the electronegativity of the graphene material can be effectively enhanced, the active sites of the reaction are increased, and the specific capacitance is improved.

4) Compared with the composition of the common conductive polymer and the graphene material, the conductive polymer is grafted on the graphene material, and due to the fact that covalent bond connection is formed between the polymer and the graphene, the transmission of electrons between the polymer and the graphene is improved, and the specific capacitance of the material is greatly improved.

5) The preparation method has the characteristics of stable process, easiness in operation, reliable quality, low cost, light weight, no pollution and the like, and has good commercial prospect.

Drawings

Other features, objects and advantages of the invention will become more apparent upon reading of the detailed description of non-limiting embodiments with reference to the following drawings:

FIG. 1 shows that nitrogen-doped graphene oxide grafted polyaniline-co-p-phenylenediamine/MnO obtained in example 1 of the present invention₂Scanning electron micrographs.

Detailed Description

The present invention will be described in detail with reference to specific examples. The following examples will assist those skilled in the art in further understanding the invention, but are not intended to limit the invention in any way. It should be noted that variations and modifications can be made by persons skilled in the art without departing from the spirit of the invention. All falling within the scope of the present invention.

Example 1

The embodiment provides nitrogen-doped graphene oxide grafted polyaniline-co-p-phenylenediamine/MnO₂The preparation method of the electrode specifically comprises the following steps:

1) preparation of nitrogen-doped graphene oxide

1g of graphene oxide, 4g of sodium dodecyl benzene sulfonate and 300mL of deionized water are added into a three-neck flask, and magnetic stirring is carried out at normal temperature to form a dispersion liquid. To the dispersion was added 0.2g pyrrole and 1.5g FeC1₃And continuously stirring for reaction for 12 hours, and filtering, washing and drying the product to obtain the graphene oxide/polypyrrole compound. And soaking the compound in 100mL of ammonium chloride solution with the mass concentration of 1% for 12h, washing and drying. And (3) putting the compound into a tube furnace, heating to 280 ℃ from 25 ℃ under the protection of argon, preserving heat for 2h, heating to 780 ℃ from 280 ℃, and preserving heat for 2h to obtain the nitrogen-doped graphene oxide (NGO).

2) Nitrogen-doped graphene oxide grafted polyaniline-co-p-phenylenediamine

And soaking the nitrogen-doped graphene oxide in a mixed solution of sulfuric acid and nitric acid for 5 hours, washing and drying to obtain the activated nitrogen-doped graphene oxide. Adding 60mL of tetrahydrofuran, 0.3g of activated nitrogen-doped graphene oxide and 0.5g of toluene-2, 4-diisocyanate into a three-neck flask, carrying out reflux reaction at 60 ℃ for 24h, washing and drying to obtain diisocyanate modified nitrogen-doped graphene oxide. 60mL of absolute ethyl alcohol, 8g of aniline, 2g of p-phenylenediamine and 0.2g of diisocyanate modified nitrogen-doped graphene oxide are added into a three-neck flask, and the mixture reacts for 2 hours at 3 ℃ under the protection of nitrogen. Dissolving 10g of ammonium persulfate in 30mL of hydrochloric acid solution with the concentration of 1mol/L, dropwise adding the ammonium persulfate/hydrochloric acid solution into the three-neck flask reaction solution, continuing to react for 24 hours, washing and drying the product, and obtaining the nitrogen-doped graphene oxide grafted polyaniline-co-p-phenylenediamine.

3) Nitrogen-doped graphene oxide grafted polyaniline-co-p-phenylenediamine/MnO₂

0.3g of cetyltrimethylammonium bromide, 40mL of ethanol, 1.5g of manganese nitrate and 35mL of deionized water were added to a three-necked flask, and dissolved by magnetic stirring at normal temperature. And (3) adding 0.2g of nitrogen-doped graphene oxide grafted polyaniline-co-p-phenylenediamine into the solution, and magnetically stirring for 5 hours at normal temperature to obtain a dispersion liquid. 1.2g of potassium permanganate was dissolved in 30mL of distilled water. Dropwise adding a potassium permanganate solution into the dispersion liquid, magnetically stirring and reacting for 24 hours at normal temperature, carrying out suction filtration on the precipitate, washing for 3 times by using ethanol, carrying out vacuum drying for 24 hours at 50 ℃, and drying the product to obtain the nitrogen-doped graphene oxide grafted polyaniline-co-p-phenylenediamine/MnO₂The scanning electron microscope is shown in FIG. 1.

4) Nitrogen-doped graphene oxide grafted polyaniline-co-p-phenylenediamine/MnO₂Preparation of the electrodes

Grafting nitrogen-doped graphene oxide onto polyaniline-co-p-phenylenediamine/MnO₂Acetylene black and PTFE were mixed as 8: 1: 1 in absolute ethyl alcohol, ultrasonically dispersing for 40min, coating on foamed nickel, vacuum drying at 60 ℃ for 6h, and then pressing under the pressure of 10MPa to prepare the nitrogen-doped graphene oxide grafted polyaniline-co-p-phenylenediamine/MnO₂And an electrode.

Prepared in this exampleNitrogen-doped graphene oxide grafted polyaniline-co-p-phenylenediamine/MnO₂The electrode has specific capacitance of 390F/g under the condition of current density of 1A/g, and the capacitance is 82.5 percent of the initial value after 800 times of cyclic use.

Example 2

The embodiment provides nitrogen-doped graphene oxide grafted polyaniline-co-p-phenylenediamine/MnO₂The preparation method of the electrode specifically comprises the following steps:

1) preparation of nitrogen-doped graphene oxide

1.2g of graphene oxide, 4g of sodium dodecyl benzene sulfonate and 300mL of deionized water are added into a three-neck flask, and magnetic stirring is carried out at normal temperature to form a dispersion liquid. To the dispersion was added 0.3g pyrrole and 1.5g FeC1₃And continuously stirring for reaction for 12 hours, and filtering, washing and drying the product to obtain the graphene oxide/polypyrrole compound. And soaking the compound in 100mL of ammonium chloride solution with the mass concentration of 0.8% for 12h, washing and drying. And (3) putting the compound into a tube furnace, heating to 300 ℃ from 25 ℃ under the protection of argon, preserving heat for 2h, heating to 800 ℃ from 300 ℃, and preserving heat for 2h to obtain the nitrogen-doped graphene oxide (NGO).

2) Nitrogen-doped graphene oxide grafted polyaniline-co-p-phenylenediamine

And soaking the nitrogen-doped graphene oxide in a mixed solution of sulfuric acid and nitric acid for 5 hours, washing and drying to obtain the activated nitrogen-doped graphene oxide. Adding 60mL of tetrahydrofuran, 0.25g of activated nitrogen-doped graphene oxide and 0.6g of toluene-2, 4-diisocyanate into a three-neck flask, carrying out reflux reaction at 58 ℃ for 24h, washing and drying to obtain diisocyanate modified nitrogen-doped graphene oxide. 60mL of absolute ethyl alcohol, 7g of aniline, 1g of p-phenylenediamine and 0.2g of diisocyanate modified nitrogen-doped graphene oxide are added into a three-neck flask, and the mixture reacts for 2 hours at 0 ℃ under the protection of nitrogen. Dissolving 10g of ammonium persulfate in 30mL of hydrochloric acid solution with the concentration of 1mol/L, dropwise adding the ammonium persulfate/hydrochloric acid solution into the three-neck flask reaction solution, continuing to react for 24 hours, washing and drying the product, and obtaining the nitrogen-doped graphene oxide grafted polyaniline-co-p-phenylenediamine.

3) Nitrogen-doped graphene oxide grafted polyaniline-co-p-phenylenediamine/MnO₂

0.3g of cetyltrimethylammonium bromide, 40mL of ethanol, 1.5g of manganese nitrate and 35mL of deionized water were added to a three-necked flask, and dissolved by magnetic stirring at normal temperature. And (3) adding 0.2g of nitrogen-doped graphene oxide grafted polyaniline-co-p-phenylenediamine into the solution, and magnetically stirring for 5 hours at normal temperature to obtain a dispersion liquid. 1.2g of potassium permanganate was dissolved in 30mL of distilled water. Dropwise adding a potassium permanganate solution into the dispersion liquid, magnetically stirring and reacting for 24 hours at normal temperature, carrying out suction filtration on the precipitate, washing for 3 times by using ethanol, carrying out vacuum drying for 24 hours at 50 ℃, and drying the product to obtain the nitrogen-doped graphene oxide grafted polyaniline-co-p-phenylenediamine/MnO₂。

4) Nitrogen-doped graphene oxide grafted polyaniline-co-p-phenylenediamine/MnO₂Preparation of the electrodes

Grafting nitrogen-doped graphene oxide onto polyaniline-co-p-phenylenediamine/MnO₂Acetylene black and PTFE were mixed as 8: 1: 1 in absolute ethyl alcohol, ultrasonically dispersing for 40min, coating on foamed nickel, vacuum drying at 60 ℃ for 6h, and then pressing under the pressure of 10MPa to prepare the nitrogen-doped graphene oxide grafted polyaniline-co-p-phenylenediamine/MnO₂And an electrode.

The nitrogen-doped graphene oxide grafted polyaniline-co-p-phenylenediamine/MnO prepared in the embodiment₂The electrode has a specific capacitance of 380F/g under the condition of a current density of 1A/g, and the capacitance is 83.1 percent of the initial value after 800 times of cyclic use.

Example 3

The embodiment provides nitrogen-doped graphene oxide grafted polyaniline-co-p-phenylenediamine/MnO₂The preparation method of the electrode specifically comprises the following steps:

1) preparation of nitrogen-doped graphene oxide

1.5g of graphene oxide, 4g of sodium dodecyl benzene sulfonate and 300mL of deionized water are added into a three-neck flask, and magnetic stirring is carried out at normal temperature to form a dispersion liquid. To the dispersion was added 0.4g pyrrole and 1.5g FeC1₃And continuously stirring for reaction for 12 hours, and filtering, washing and drying the product to obtain the graphene oxide/polypyrrole compound. Soaking the compound in 100mL ammonium chloride solution with mass concentration of 0.6% for 12h, washing,And (5) drying. And (3) putting the compound into a tube furnace, heating from 25 ℃ to 290 ℃ under the protection of argon, preserving heat for 2h, then heating from 290 ℃ to 7600 ℃ and preserving heat for 2h to obtain the nitrogen-doped graphene oxide (NGO).

2) Nitrogen-doped graphene oxide grafted polyaniline-co-p-phenylenediamine

And soaking the nitrogen-doped graphene oxide in a mixed solution of sulfuric acid and nitric acid for 5 hours, washing and drying to obtain the activated nitrogen-doped graphene oxide. Adding 60mL of tetrahydrofuran, 0.28g of activated nitrogen-doped graphene oxide and 0.55g of toluene-2, 4-diisocyanate into a three-neck flask, carrying out reflux reaction at 58 ℃ for 24h, washing and drying to obtain diisocyanate modified nitrogen-doped graphene oxide. 60mL of absolute ethyl alcohol, 6g of aniline, 1g of p-phenylenediamine and 0.2g of diisocyanate modified nitrogen-doped graphene oxide are added into a three-neck flask, and the mixture reacts for 2 hours at 1 ℃ under the protection of nitrogen. Dissolving 10g of ammonium persulfate in 30mL of hydrochloric acid solution with the concentration of 1mol/L, dropwise adding the ammonium persulfate/hydrochloric acid solution into the three-neck flask reaction solution, continuing to react for 24 hours, washing and drying the product, and obtaining the nitrogen-doped graphene oxide grafted polyaniline-co-p-phenylenediamine.

3) Nitrogen-doped graphene oxide grafted polyaniline-co-p-phenylenediamine/MnO₂

0.3g of cetyltrimethylammonium bromide, 40mL of ethanol, 1.5g of manganese nitrate and 35mL of deionized water were added to a three-necked flask, and dissolved by magnetic stirring at normal temperature. And (3) adding 0.2g of nitrogen-doped graphene oxide grafted polyaniline-co-p-phenylenediamine into the solution, and magnetically stirring for 5 hours at normal temperature to obtain a dispersion liquid. 1.2g of potassium permanganate was dissolved in 30mL of distilled water. Dropwise adding a potassium permanganate solution into the dispersion liquid, magnetically stirring and reacting for 24 hours at normal temperature, carrying out suction filtration on the precipitate, washing for 3 times by using ethanol, carrying out vacuum drying for 24 hours at 50 ℃, and drying the product to obtain the nitrogen-doped graphene oxide grafted polyaniline-co-p-phenylenediamine/MnO₂。

4) Nitrogen-doped graphene oxide grafted polyaniline-co-p-phenylenediamine/MnO₂Preparation of the electrodes

Grafting nitrogen-doped graphene oxide onto polyaniline-co-p-phenylenediamine/MnO₂Acetylene black and PTFE were mixed as 8: 1: 1 in absolute ethyl alcoholAfter being dispersed for 40min by ultrasonic, the mixture is coated on foamed nickel, dried for 6h in vacuum at 60 ℃, and then pressed into a sheet under the pressure of 10MPa to prepare the nitrogen-doped graphene oxide grafted polyaniline-co-p-phenylenediamine/MnO₂And an electrode.

The nitrogen-doped graphene oxide grafted polyaniline-co-p-phenylenediamine/MnO prepared in the embodiment₂The electrode has specific capacitance of 377F/g under the condition of current density of 1A/g, and the capacitance is 80.2% of the initial value after 800 times of cyclic use.

Comparative example 1

Different from the embodiment 1, the method omits the step 1), directly adding the graphene oxide into the reaction in the step 2), and finally obtaining the graphene oxide grafted polyaniline-co-p-phenylenediamine/MnO₂The electrode has a specific capacitance of 310F/g under the condition of a current density of 1A/g, and the capacitance is 81.1 percent of the initial value after the electrode is recycled for 800 times.

Comparative example 2

Different from the embodiment 1, the method omits the step 2), directly adds the nitrogen-doped graphene oxide into the reaction in the step 3), and finally obtains the nitrogen-doped graphene oxide/MnO₂The electrode has a specific capacitance of 234F/g under the condition of a current density of 1A/g, and the capacitance is 78.9 percent of the initial value after 800 times of cyclic use.

Comparative example 3

Different from the embodiment 1, in the step 2), only aniline is added in the reaction, and p-phenylenediamine is not added, so that the nitrogen-doped graphene oxide grafted polyaniline/MnO is finally obtained₂The electrode has specific capacitance of 319F/g under the condition of current density of 1A/g, and the capacitance is 76.8 percent of the initial value after 800 times of cyclic use.

Comparative example 4

The difference from the embodiment 1 is that the step 3) is omitted, and the nitrogen-doped graphene oxide grafted polyaniline-co-p-phenylenediamine electrode is finally obtained, wherein the specific capacitance is 280F/g under the condition that the current density is 1A/g, and the capacitance is 77.1% of the initial value after 800 times of recycling.

The foregoing description of specific embodiments of the present invention has been presented. It is to be understood that the present invention is not limited to the specific embodiments described above, and that various changes and modifications may be made by one skilled in the art within the scope of the appended claims without departing from the spirit of the invention.