CN104934236A - Method of preparing electroactive molecule grafted graphene doped conductive polymer electrode materials - Google Patents

Abstract

A preparation method of electroactive molecular grafted graphene-doped conductive polymer electrode material, which is to add conductive polymer monomers to electroactive graphene aqueous solution, mix uniformly, add oxidant, and stir at -10-30°C After reacting for 6-24 hours, the electroactive graphene-doped conductive polymer electrode material is obtained. The invention utilizes the oxygen-containing functional groups on the surface of the electroactive graphene and the electroactive molecules grafted on the surface to perform in-situ doping on the conductive polymer. The anthraquinone electroactive molecules grafted on the surface of graphene endow graphene with good redox activity and dispersion, and broaden its potential window. After doping conductive polymers, it can endow conductive polymers with high conductivity and stability. As a supercapacitor electrode material, it exhibits high energy density and cycle stability.

Description

A preparation method of electroactive molecule grafted graphene doped conductive polymer electrode material

technical field

The invention relates to a preparation method of an electroactive molecule grafted graphene-doped conductive polymer electrode material, belonging to the field of supercapacitor electrode materials.

Background technique

As a new type of energy storage device with green environmental protection and excellent performance, supercapacitor has the advantages of high power density, short charging time, long service life and no pollution to the environment. The field has wide application. However, its energy density (generally <10Wh/kg) is still low, which limits its application in the field of mass storage. Electrode materials are an important part of supercapacitors and a key factor affecting the performance and production cost of supercapacitors. The electrode materials currently used to prepare supercapacitors are mainly divided into three categories: carbon, metal oxides, and conductive polymers.

High surface area carbon electrode materials are cheap to manufacture, but low energy density is obtained; noble metal oxides can obtain high energy density, but the material cost is high. Conductive polymers, such as polyaniline (PANI), polypyrrole (PPy), polythiophene (PTh) and their derivatives, etc., because of their fast electrochemical charge and discharge kinetics (that is, rapid doping and dedoping processes) , The charge can be stored in the entire material volume, and the cost is lower than that of noble metal oxides, which has attracted people's attention, but its poor cycle stability is the bottleneck restricting the further development and application of conductive polymers in supercapacitors.

Therefore, conductive polymer/graphene composite electrode materials have become a research hotspot in recent years. The composite of conductive polymer and graphene is usually realized by in-situ chemical or electrochemical polymerization, which has a good research basis [Meng YN, Wang K, Zhang YJ, Wei ZX. Hierarchical porous graphene/polyaniline composite film with superior rate performance for flexible supercapacitors. Adv. Mater., 2103, 25:6985-6990.Kumar NA, Choi HJ, Shin YR, Ba Changai DW, Da Changai DW, JB. Polyanline-grafted reduced graphene oxide for efficient electrochemical supercapacitors. ACS Nano, 2012,6:1715-1723. Zhao Y, Liu J, Hu Y, Cheng HH, Hu CG, Jiang CC, et al. based on polypyrrole-mediated graphene foam electrodes. Adv. Mater.,2013,25:591-595.]. However, the improvement of the cycle stability of the composite electrode material depends on the amount of graphene, and the addition of too much graphene will cause the agglomeration of graphene, which is not conducive to the improvement of its energy density. Therefore, how to achieve the win-win situation of cycle stability and energy density of conductive polymer/graphene composite electrode materials on the existing basis still needs further in-depth research.

Contents of the invention

In order to solve the above problems, the object of the present invention is to provide a preparation method of electroactive molecule grafted graphene-doped conductive polymer electrode material, grafting anthraquinone electroactive molecules on the surface of graphene to give graphene a good Redox activity and dispersibility, and broaden its potential window, improve its energy density. Secondly, by choosing graphene as the matrix, endowing anthraquinone-type electroactive molecules with good doping stability, preparing conductive polymers with stable doped nanostructures, and improving their cycle stability. This method has not been reported at home and abroad.

In order to realize above-mentioned purpose of the invention, the technical scheme that the present invention adopts is as follows:

A preparation method of electroactive molecule grafted graphene-doped conductive polymer electrode material, the characteristic steps are as follows:

(1) Dissolve anthraquinone electroactive molecules grafted graphene in water, stir and disperse with ultrasonic waves to form a solution; the anthraquinone electroactive molecules are 1-aminoanthraquinone, 1,4-diaminoanthraquinone , one of 2,6-diaminoanthraquinone, 1-aminoanthraquinone-5-sulfonate, 1-aminoanthraquinone-2-sulfonate, 1-aminoanthraquinone-2-carboxylate, The concentration of anthraquinone electroactive molecules grafted graphene is 0.01g/L-1g/L;

(2) Add conductive polymer monomers to the above solution, stir and disperse with ultrasonic waves to form a reaction system. The conductive polymer monomers used are aniline, m-phenylenediamine, pyrrole, 3,4-ethylenedioxythiophene One of them, the mass ratio of the anthraquinone electroactive molecule grafted graphene to the conductive polymer monomer is: 1:1-1:99.

(3) Dissolve the oxidizing agent in water to make a solution, add it to the reaction system formed in step (2) at one time, mix evenly, and the molar ratio of the conductive polymer monomer to the oxidizing agent is 1:1-1:8. Described oxidizing agent is ammonium persulfate, potassium persulfate or anhydrous ferric trichloride;

(4) React at -10-30°C for 6-24h under stirring conditions, wash the product repeatedly with deionized water, and dry it in a vacuum oven at a drying temperature of 60°C for 24h to obtain electroactive graphite Alkene-doped conducting polymer electrode materials.

The present invention aims at the problems of low energy density and poor cycle stability existing in the current supercapacitor electrode materials, combining the good electrochemical activity of anthraquinone electroactive molecule grafted graphene and the unique doping advantages of conductive polymers, the prepared electrode Active graphene-doped conductive polymer composites can be used as supercapacitor electrode materials.

The positive effect of the present invention is as follows:

1. Use the oxygen-containing groups of anthraquinone electroactive molecules grafted on the surface of graphene (such as formula (I): 1-aminoanthraquinone-5-sodium sulfonate grafted graphene) and the conductive polymer monomer The hydrogen bond and π-π interaction realize the effect of doping and inducing the growth of the conductive polymer. The graphene grafted with anthraquinone electroactive molecules can also provide electrons for the conductive polymer while serving as the electroactive molecular matrix. Channels can realize the controllable preparation of conductive polymers stably doped with nanostructures. Such a design has not been reported in the literature at home and abroad.

Formula (I)

2. The electroactive graphene-doped conductive polymer with redox activity prepared by the present invention has a high energy density and maintains good cycle stability. It has excellent electrochemical properties as a supercapacitor electrode material and has a wide range of applications prospect.

3. The present invention adopts a one-step method to carry out in-situ polymerization reaction, and the equipment is simple, easy to operate, and easy to expand scale production.

Detailed ways

The above content of the present invention will be further described in detail below through specific examples. But it should not be interpreted as that the content of the present invention is limited to the following examples.

Embodiment 1 A kind of preparation method of electroactive molecule grafted graphene doped conductive polymer electrode material, the steps are as follows:

(1) Graft 1mg 1-aminoanthraquinone to graphene (for the preparation method see: Wu Q, Sun YQ, Bai H, Shi GQ. High-performance supercapacitor electrodes based on graphene hydrogels modified with 2-aminoanthraquinone moieties. Phys. Chem . Chem. Phys., 2011, 13: 11193-11198. The preparation method of 1-aminoanthraquinone grafted graphene is disclosed here, and the implementation of 2-6 method is not disclosed, but the basic preparation principle is the same as this disclosed method, only The difference between reaction time and temperature) was dissolved in 100mL water, stirred and dispersed by ultrasonic waves to form a solution of anthraquinone electroactive molecules grafted graphene (electroactive graphene) with a concentration of 0.01g/L, and set aside.

(2) Add 99 mg (1.0645 mmol) aniline (purchased from Sinopharm Chemical Reagent Co., Ltd.) to the above dispersion, stir and disperse with ultrasonic waves to form a reaction system (1:99).

(3) Dissolve 0.2429g (1.0645mmol) of ammonium persulfate (purchased from Sinopharm Chemical Reagent Co., Ltd.) in water to make a solution, add it to the reaction system formed in step (2) at one time, and mix well.

(4) Reaction at -10°C for 24h under stirring conditions, the product was repeatedly washed with deionized water, and dried in a vacuum oven at a drying temperature of 60°C for 24h to obtain electroactive graphene doped conductive polymer electrode material.

Embodiment 2. A preparation method of electroactive molecule grafted graphene-doped conductive polymer electrode material, which differs from Example 1 in that 1mg 1-aminoanthraquinone grafted graphene becomes 5mg 1,4-diaminoanthraquinone Grafted graphene, 99mg (1.0645mmol) aniline changed to 0.35g (5.2239mmol) pyrrole, 0.2429g (1.0645mmol) ammonium persulfate changed to 1.6946g (10.4477mmol), -10℃ for 24h and changed to stirring condition at 0 ℃ reaction 18h.

Embodiment 3. A preparation method of electroactive molecule grafted graphene-doped conductive polymer electrode material, which differs from Example 1 in that 1mg 1-aminoanthraquinone grafted graphene becomes 10mg 2,6-diaminoanthraquinone Grafted graphene, 99mg (1.0645mmol) aniline to 0.5g (4.6296mmol) m-phenylenediamine, 0.2429g (1.0645mmol) ammonium persulfate to 5.0055g (18.5184mmol) potassium persulfate, react at -10℃ for 24h Change to stirring conditions and react at 10°C for 18h.

Embodiment 4. A kind of preparation method of electroactive molecule grafted graphene-doped conductive polymer electrode material, its place different from embodiment 1 is that 1mg 1-aminoanthraquinone grafted graphene becomes 40mg 1-aminoanthraquinone-5- Sulfonate-grafted graphene, 99 mg (1.0645 mmol) aniline to 1.2 g (8.44 mmol) 3,4-ethylenedioxythiophene, 0.2429 g (1.0645 mmol) ammonium persulfate to 6.8448 g (42.2 mmol) none Ferric chloride in water, react at 10°C for 24h, change to stirring condition and react at 20°C for 12h.

Embodiment 5. A preparation method of electroactive molecule grafted graphene-doped conductive polymer electrode material, which is different from Example 1 in that 1mg 1-aminoanthraquinone grafted graphene becomes 70mg 1-aminoanthraquinone-2- Sulfonate grafted graphene, the mass of aniline changed from 99mg (1.0645mmol) to 0.7g (7.5269mmol), the mass of ammonium persulfate changed from 0.2429g (1.0645mmol) to 12.0235g (52.6883mmol), -10℃ After 24 hours of reaction, the reaction was changed to stirring condition at 25°C for 8 hours.

Embodiment 6. A preparation method of electroactive molecule grafted graphene-doped conductive polymer electrode material, which is different from Example 1 in that 1mg 1-aminoanthraquinone grafted graphene becomes 100mg 1-aminoanthraquinone-2- Formate grafted graphene, the mass of aniline changed from 99mg (1.0645mmol) to 0.1g (1.0753mmol), the mass of ammonium persulfate changed from 0.2429g (1.0645mmol) to 1.9630g (8.6021mmol), -10℃ The reaction was changed to stirring condition for 24h and the reaction was carried out at 30°C for 6h.

Embodiment 1-6 prepares the performance parameter chart 1 of composite material as shown in chart 1, and the comparative example in table 1 is the conductive polymer electrode material performance parameter of undoped electroactive molecule grafted graphene:

Table 1

Claims (8)

1. a preparation method for the conductive doped polymer electrode material of electric active molecule graft grapheme, is characterized in that step is as follows:

By soluble in water for the Graphene of electric active molecule grafting, stir and utilize ultrasonic wave to disperse to form solution, for subsequent use;

Conducting polymer monomer is added in above-mentioned solution, stirs and utilize ultrasonic wave to disperse forming reactions system, for subsequent use;

Be dissolved in the water by oxidant and make solution, the disposable reaction system adding step (2) and formed, mixes;

(4) react 6-24h at stirring condition in-10-30 DEG C, product deionized water cleans repeatedly, and in vacuum drying chamber inner drying, obtains the conductive doped polymer electrode material of electroactive Graphene.

2. the preparation method of the conductive doped polymer electrode material of electric active molecule graft grapheme according to claim 1, it is characterized in that described electric active molecule is 1-amino anthraquinones, 1,4-diamino-anthraquinone, 2,6-diamino-anthraquinone, 1-amino anthraquinones-5-sulfonate, 1-amino anthraquinones-2-sulfonate, the one in 1-amino anthraquinones-2-formates.

3. the preparation method of the conductive doped polymer electrode material of electric active molecule graft grapheme according to claim 1, it is characterized in that the conducting polymer monomer adopted in step (2) is the one in aniline, m-phenylene diamine (MPD), pyrroles, 3,4-ethylene dioxythiophene.

4. the preparation method of the conductive doped polymer electrode material of electric active molecule graft grapheme according to claim 1, is characterized in that the oxidant adopted in step (3) is the one of ammonium persulfate, potassium peroxydisulfate, anhydrous ferric trichloride.

5. the preparation method of the conductive doped polymer electrode material of electric active molecule graft grapheme according to claim 1, is characterized in that the concentration of electric active molecule graft grapheme solution in step (1) is 0.01-1g/L.

6. the preparation method of the conductive doped polymer electrode material of electric active molecule graft grapheme according to claim 1, is characterized in that the mass ratio of electric active molecule graft grapheme and conducting polymer monomer in step (2) is 1:1-1:99.

7. the preparation method of the conductive doped polymer electrode material of electric active molecule graft grapheme according to claim 1, is characterized in that the mol ratio of conducting polymer monomer and initator in step (3) is 1:1-1:8.

8. the preparation method of the conductive doped polymer electrode material of electric active molecule graft grapheme according to claim 1, it is characterized in that the bake out temperature of step (4) is 60 DEG C, drying time is 24h.