CN110415997B

CN110415997B - Preparation method of self-healing flexible solid-state supercapacitor

Info

Publication number: CN110415997B
Application number: CN201910656781.2A
Authority: CN
Inventors: 董玉成; 林叶茂
Original assignee: Zhaoqing South China Normal University Optoelectronics Industry Research Institute
Current assignee: Zhaoqing South China Normal University Optoelectronics Industry Research Institute
Priority date: 2019-07-19
Filing date: 2019-07-19
Publication date: 2021-09-17
Anticipated expiration: 2039-07-19
Also published as: CN110415997A

Abstract

The invention belongs to the technical field of capacitors, and particularly relates to a preparation method of a self-healing flexible solid-state supercapacitor. The preparation method of the self-healing flexible solid-state supercapacitor comprises the following steps: (1) preparing polydopamine-polyacrylamide-sulfuric acid hydrogel; (2) and preparing the polyaniline flexible super capacitor. The method synthesizes the hydrogel capacitor in one step, greatly reduces the large interface resistance of electrode materials and electrolyte due to poor contact, and the contact between the electrolyte and the conductive polymer improves the performance of the super capacitor by providing excellent electrochemical dynamic performance and remarkable structural stability.

Description

Preparation method of self-healing flexible solid-state supercapacitor

Technical Field

The invention belongs to the technical field of capacitors, and particularly relates to a preparation method of a self-healing flexible solid-state supercapacitor.

Background

With the continuous development of economy, the exhaustion of petroleum resources, environmental pollution and the deterioration degree of global climate are all aggravated, and the development and comprehensive utilization of new energy and energy-saving technologies become very necessary subjects. As the most promising new green energy source in this century, supercapacitors are being gradually applied to various fields. Flexible energy storage devices (batteries such as supercapacitors) have received widespread attention today. Flexible all-solid-state supercapacitors represent a new type of flexible device that can operate in curved, stretched, and even twisted conditions, however obtaining all-solid-state supercapacitors with high electrochemical performance and flexibility remains a significant challenge. The performance of the flexible supercapacitor mainly depends on the performance of electrode materials and the configuration of equipment, and the electrode materials of the flexible supercapacitor mainly comprise different nano carbon materials, conductive polymers and transition metal compounds.

The super capacitor mainly comprises three parts, namely an electrode, a diaphragm and an electrolyte. Scientists have conducted intensive research into electrodes over the years, mainly including carbon materials, transition metal oxides, and electronically conductive polymers. The research on electrolytes is expanding, and the research is mainly focused on two forms, namely liquid state and solid state. The solid electrolyte is small, convenient, safe and leak-free, and gradually becomes the focus of research, and the solid electrolyte takes a polymer as a matrix and is generally divided into a dry solid polymer electrolyte, a gel polymer electrolyte anda composite polymer electrolyte. Dry solid polymer electrolytes have low conductivity at room temperature (10)⁸～10⁷S/cm), the use of which is limited, and thus the gel polymer electrolyte has been the focus of research, but the preparation thereof generally uses organic solvents, which are harmful to the environment, and although the electrochemical stability window of water is only 1.23V, the preparation of gel electrolyte by using water instead of organic solvents has become a need, and the equipment cost can also be reduced.

Disclosure of Invention

The invention aims to provide a preparation method of a self-healing flexible solid-state supercapacitor aiming at the existing defects, the method synthesizes a hydrogel capacitor in one step, the large interface resistance of an electrode material and an electrolyte due to poor contact is greatly reduced, and the contact between the electrolyte and a conductive polymer improves the performance of the supercapacitor by providing excellent electrochemical dynamic performance and remarkable structural stability.

The technical scheme of the invention is as follows: a preparation method of a self-healing flexible solid-state supercapacitor comprises the following steps:

(1) preparation of polydopamine-polyacrylamide-sulfuric acid hydrogel: dissolving dopamine hydrochloride powder in an alkaline aqueous solution, and stirring to obtain a uniform solution; then acrylamide, ammonium persulfate, tetramethylethylenediamine and H₂SO₄Sequentially adding thiosalicylic acid and the solution into the uniform solution in sequence, stirring under the ice bath condition of 0 ℃, and finally carrying out water bath reaction for 12 hours at 70 ℃ to form polydopamine-polyacrylamide-sulfuric acid hydrogel;

(2) preparing a polyaniline flexible supercapacitor: soaking the polydopamine-polyacrylamide-sulfuric acid hydrogel obtained in the step (1) in a solution prepared from aniline, ammonium persulfate and H₂SO₄And in-situ polymerization is carried out on the formed mixed solution at room temperature to obtain the polyaniline flexible supercapacitor.

0.02g of dopamine hydrochloride powder in the step (1); the alkaline aqueous solution is 10mLpH 11 NaOH aqueous solution; 2g of acrylamide, 0.25g of ammonium persulfate, 10 mu L of tetramethylethylenediamine and H₂SO₄At a concentration of 98%0.98g of thiosalicylic acid and 0.003g of thiosalicylic acid.

In the step (2), 0.093g of aniline, 0.228g of ammonium persulfate and H₂SO₄The concentration is 0.98g of 98%.

Dissolving and stirring dopamine hydrochloride powder in the step (1) for 20min at the stirring speed of 350 r/min; stirring for 10min under ice bath condition, wherein the stirring speed is 350 r/min.

The in-situ polymerization in the step (2) was carried out for 3 hours.

The invention has the beneficial effects that: compared with the prior art, the one-step synthesized hydrogel capacitor can greatly reduce the interface resistance of the electrode material and the electrolyte due to poor contact, and the contact between the electrolyte and the conductive polymer improves the performance of the supercapacitor by providing excellent electrochemical dynamic performance and remarkable structural stability. Meanwhile, the self-healing polydopamine-polyacrylamide-sulfuric acid hydrogel electrolyte has good self-healing performance, ionic conductivity, stretchability and ductility, so that the mechanical performance, the electrochemical performance and the fatigue resistance of the flexible solid-state supercapacitor can be improved.

Drawings

Fig. 1 is a scanning electron microscope picture of the polyaniline flexible supercapacitor prepared in example 1.

Fig. 2 is a graph showing the capacitance change of the polyaniline flexible supercapacitor prepared in example 1 at different scanning rates.

FIG. 3 shows the voltage of 50 mV. s-¹And cv plot under bending condition of 0-180 degrees.

Fig. 4 shows the capacitance change of the polyaniline flexible supercapacitor prepared in example 1 before and after self-healing.

Detailed Description

The invention is further described with reference to the drawings and the detailed description. The raw materials involved therein were all obtained by mclin reagents ltd.

Example 1

The preparation method of the self-healing flexible solid-state supercapacitor comprises the following steps:

(1) preparation of polydopamine-polyacrylamide-sulfuric acid hydrogel: firstly, 0.02g of dopamine hydrochloride powder is dissolved in 10ml of NaOH aqueous solution with the pH value of 11, and the solution is stirred for 20min under the condition that the stirring speed is 350r/min to obtain uniform solution; then 2g of acrylamide, 0.25g of ammonium persulfate, 10. mu.L of tetramethylethylenediamine, 0.98gH with a concentration of 98%₂SO₄Sequentially adding 0.003g of thiosalicylic acid and the uniform solution in sequence, stirring for 10min at the ice bath condition of 0 ℃, wherein the stirring speed is 350r/min, and finally carrying out water bath reaction for 12h at 70 ℃ to form polydopamine-polyacrylamide-sulfuric acid hydrogel;

(2) preparing a polyaniline flexible supercapacitor: soaking the polydopamine-polyacrylamide-sulfuric acid hydrogel obtained in the step (1) in a solution prepared from 0.093g of aniline, 0.228g of ammonium persulfate and 98% of 0.98g of H₂SO₄In the mixed solution, the polyaniline flexible supercapacitor is obtained by in-situ polymerization for 3 hours at room temperature, the morphology of the polyaniline flexible supercapacitor is shown in figure 1, and the polyaniline can be uniformly polymerized on a hydrogel three-dimensional network. The capacitance change of the obtained polyaniline flexible super capacitor is detected at different scanning rates, and the result is shown in fig. 2, the capacitance of the polyaniline flexible super capacitor reaches 92.5mF cm < -2 > at the scanning rate of 10mV s < -1 >, the capacitance gradually decreases along with the increase of the scanning rate, and the capacitance retention rate of the polyaniline flexible super capacitor is more than 81.5% at the scanning rate of 200mV s < -1 >. FIG. 3 shows that the obtained polyaniline flexible super capacitor is at 50 mV.s^-1The cv graph under the bending condition of 0-180 degrees is shown in a, the cv graph of the polyaniline flexible supercapacitor under the bending condition of 0-180 degrees is basically unchanged, the polyaniline flexible supercapacitor can keep good electrochemical stability under different deformation conditions, and the capacitance retention rate of the polyaniline flexible supercapacitor is still kept at 99.1% after the polyaniline flexible supercapacitor is cycled for 1000 circles. Fig. 4 shows the capacitance change of the obtained polyaniline flexible supercapacitor before and after self-healing, and it can be seen that the capacitance of the PSC polyaniline flexible supercapacitor before and after self-healing remains substantially unchanged.

Claims

1. A preparation method of a self-healing flexible solid-state supercapacitor comprises the following steps:

(2) preparing a polyaniline flexible solid-state supercapacitor: soaking the polydopamine-polyacrylamide-sulfuric acid hydrogel obtained in the step (1) in a solution prepared from 0.093g of aniline, 0.228g of ammonium persulfate and 98% of 0.98g of H₂SO₄And in-situ polymerizing for 3 hours in the formed mixed solution at room temperature to obtain the polyaniline flexible solid-state supercapacitor.