CN115036147A - Stretchable linear all-gel supercapacitor and preparation method thereof - Google Patents

Abstract

The invention discloses a stretchable linear all-gel supercapacitor and a preparation method thereof, belonging to the technical field of energy storage. The supercapacitor comprises a helical intertwined hydrogel electrode and a gel electrolyte attached to the surface of the hydrogel electrode; the hydrogel electrode is obtained by the cross-linking reaction of a conductive polymer and an additive. In the present invention, a stretchable wire-shaped conductive hydrogel electrode is first prepared through the physical cross-linking of the additive and the conductive polymer, and then the prepared electrode is infiltrated into a gel electrolyte and assembled into a helical wire-shaped structure of an all-gel supercapacitor. The supercapacitor prepared by the invention has the characteristics of excellent electrochemical performance, intrinsic stretchability, simple structure, arbitrary deformation and weaving and the like, and can be used as an energy storage device in a wearable device.

Description

Stretchable linear all-gel supercapacitor and preparation method thereof

technical field

The invention belongs to the technical field of energy storage, and in particular relates to a stretchable linear all-gel supercapacitor and a preparation method thereof.

Background technique

One-dimensional supercapacitors (SCs) have emerged as a potential driver of emerging electronics in recent years due to their unique advantages in energy storage and mechanical flexibility.

So far, the electrodes of most wire-like SCs are mostly conductive materials deposited on wire-like fabrics, which not only increases the extra mass of the device, but also greatly reduces the capacitance of the wire-like SCs because the substrate itself cannot provide electrical assistance. and reduce its power density and energy density; the linear SCs assembled with this electrode not only tend to slip when the device is bent, but also increase the contact resistance between the electrode and the electrolyte part; in addition, due to the existence of the fabric substrate, this The linear SCs prepared in this way are not stretchable in the flat state, which limits the practical application in flexible wearable devices.

In order to construct SCs with high performance, large deformation, stretchability, small size, light weight, and high integration, stretchable linear all-gel SCs are a promising and feasible technical solution. The key challenge is to develop intrinsically stretchable wire-like hydrogel electrode materials with high carrier mobility, large accessible surface area.

SUMMARY OF THE INVENTION

Technical problem to be solved: In view of the above technical problems, the present invention provides a stretchable linear all-gel supercapacitor and a preparation method thereof, which have excellent electrochemical performance, intrinsic stretchability, simple structure, and can be arbitrarily deformed and Weaving and other characteristics, and can be used as energy storage devices in wearable devices.

Technical solution: a stretchable linear all-gel supercapacitor, comprising a helical intertwined hydrogel electrode and a gel electrolyte attached to the surface of the hydrogel electrode; the hydrogel electrode is composed of a conductive polymer obtained by cross-linking reaction with additives, wherein the additives are dimethyl sulfoxide, ethylene glycol, polyethylene glycol p-isooctyl phenyl ether, sodium dodecyl sulfate, sodium dodecyl benzene sulfonate and one or more of fluorosurfactants.

Preferably, the conductive polymer is one or more of polythiophene, polypyrrole and polyaniline.

Preferably, the gel electrolyte is an organic electrolyte.

A preparation method of a stretchable linear all-gel supercapacitor, comprising the following steps:

(1) Add additives to the conductive polymer, and stir to obtain a conductive polymer mixed solution;

(2) heating the prepared conductive polymer mixed solution to induce physical crosslinking to obtain a conductive hydrogel;

(3) preparing the prepared conductive hydrogel into a linear hydrogel electrode;

(4) The prepared hydrogel electrode is soaked in the gel electrolyte, and then wound with each other to form a spiral-shaped all-gel supercapacitor.

Preferably, the mass of the additive in the step (1) is 1-40% of the conductive polymer mixed solution.

Preferably, the heating temperature in the step (2) is 25-130°C.

Preferably, the heating time in the step (2) is 1 to 24 hours.

Preferably, the specific preparation method of the step (3) is a combination of one or more of 3D printing, wet spinning and physical segmentation.

Beneficial effects: Compared with the traditional wire electrodes, which are prepared by depositing active materials on fibrous textile materials, each component of the stretchable wire all-gel supercapacitor prepared by the present invention is all gel, and does not contain other The substrate reduces the volume and weight of the device; at the same time, because the prepared electrode material has intrinsic stretchable properties, the entire device has a simple structure, high material utilization, and low cost of green environmental protection; and the supercapacitor's all-gel composition Part of it can make the electrode have excellent adhesion between the electrolyte, which can avoid the interlayer slip that is easily generated when bending or kinking during actual use, and has the characteristics of good mechanical stability and compliance; in addition, the device The all-gel linear structure can maximize the use of the electrode surface area to expand the interface ion adsorption charge storage, thereby increasing the electrochemical performance of the supercapacitor; Integration and other characteristics, it has huge application prospects in the field of flexible electronic wearables in the future.

Description of drawings

1 is a schematic diagram of the preparation process of the stretchable linear all-gel supercapacitor of the present invention, wherein A and B are hydrogel working electrodes, and C is a gel electrolyte;

2 is a schematic cross-sectional structure diagram of a stretchable linear all-gel supercapacitor prepared by the present invention, wherein A and B are hydrogel working electrodes, and C is a gel electrolyte;

Fig. 3 is the stretchable linear hydrogel electrodes of different sizes prepared in Example 1;

4 is a weaving display diagram of the stretchable linear hydrogel electrode prepared in Example 1;

5 is a display diagram of the stretchable linear all-gel supercapacitor prepared in Example 2 under different deformation states;

6 is a cyclic voltammetry (CV) curve diagram of the stretchable linear all-gel supercapacitor prepared in Example 2;

7 is a galvanostatic charge-discharge (GCD) curve diagram of the stretchable linear all-gel supercapacitor prepared in Example 2;

8 is a cyclic voltammetry (CV) curve diagram of the stretchable linear all-gel supercapacitor obtained in Example 2 under different stretching states;

9 is a cyclic voltammetry (CV) curve diagram of the stretchable linear all-gel supercapacitor prepared in Example 3;

10 is a galvanostatic charge-discharge (GCD) curve diagram of the stretchable linear all-gel supercapacitor prepared in Example 3.

Detailed ways

The present invention will be further described below with reference to the accompanying drawings and specific embodiments.

Example 1

m，100

m，150

m，200

m不同尺寸的可拉伸线状水凝胶电极，如图3；该可拉伸线状水凝胶电极，可以通过 编织等形式满足可穿戴设备多样性需求，如图4。 0.384 g of ethylene glycol (EG) was added to 4.416 g of PEDOT:PSS (Heraeus PH1000), and 0.2 g of Triton X-100 was added after mixing to obtain a mixed solution of PEDOT:PSS; The mold was placed in a blast drying oven at 40 °C for 12 h, and then annealed at 130 °C for 30 min to obtain a film-like PEDOT:PSS hydrogel; the obtained film-like PEDOT:PSS hydrogel was prepared by physical cutting.

m, 100

m, 150

m, 200

m Stretchable linear hydrogel electrodes of different sizes, as shown in Figure 3; the stretchable linear hydrogel electrodes can meet the diverse needs of wearable devices by weaving and other forms, as shown in Figure 4.

Example 2

As shown in Figure 1, the stretchable linear hydrogel electrode prepared in Example 1 was assembled into a stretchable linear hydrogel supercapacitor:

m、长8 cm可拉伸线状水凝胶电极两根，将两根电极浸润 到凝胶电解质中并取出后组装成螺旋线状结构的全凝胶超级电容器，其截面如图2所示。 Add 1 g of PVA, 1 g of glycerol and 0.6 g of NaCl to 10 mL of deionized water, and dissolve at 90 °C for 4 h to prepare a gel electrolyte; take a diameter of 100

m. Two stretchable linear hydrogel electrodes with a length of 8 cm. Immerse the two electrodes into the gel electrolyte and take them out to assemble a helical structure of the all-gel supercapacitor. The cross section is shown in Figure 2. .

The prepared stretchable fibrous all-gel supercapacitors have excellent deformability, as shown in Figure 5.

The electrochemical activity was characterized by cyclic voltammetry (CV) and galvanostatic charge-discharge (GCD), as shown in Figure 6 and Figure 7, respectively. 6 is a cyclic voltammetry diagram of the stretchable linear all-gel supercapacitor prepared in Example 2 of the present invention. It can be seen from Fig. 6 that the shapes of the CV curves remain rectangular-like when the scanning speed is from 10 mV s ^-1 to 200 mV s ^-1 . It is indicated that the supercapacitor prepared according to the method of the present application has excellent electrochemical activity and stable performance. 7 is a galvanostatic charge-discharge curve diagram of the stretchable supercapacitor prepared in Example 2 of the present invention. It can be seen from Figure 7 that the current density is from 5 mA g ^-1 to 25 mA g ^-1 , and the shape of the GCD curve is a standard isosceles ^{triangle .} The mass specific capacitances at current densities of ^-1 and 25 mA g ^-1 are 1125 mF g ^-1 , 986 mF g ^-1 , 894 mF g ^-1 and 709 mF g ^-1 , respectively.

Cyclic voltammetry (CV) was used to characterize the electrochemical activity of the stretchable linear all-gel supercapacitor of Example 2 in the original state and in the stretched state of 10%, 20%, 30%, 40%, and 50%, As shown in Fig. 8, the excellent rectangular-like CV curves are still maintained, indicating that the assembled device still has excellent electrochemical stability in the highly stretched state.

Example 3

Add 0.276 g of ethylene glycol (EG) to 4.324 g of PEDOT:PSS (Heraeus PH1000), and after mixing evenly, add 0.4 g of sodium dodecyl sulfate (SDS) to obtain a PEDOT:PSS mixed solution; The PSS mixed solution was drop-cast into the mold, placed in a blast drying oven at 40 °C for 12 h, and then annealed at 130 °C for 30 min to obtain a film-like PEDOT:PSS hydrogel; Stretchable wire-like hydrogel electrodes were prepared by cutting.

The stretchable wire-shaped hydrogel electrode is then assembled into a stretchable wire-shaped water all-gel supercapacitor:

Add 1 g of PVA, 1 g of glycerol and 0.6 g of NaCl to 10 mL of deionized water, and dissolve at 90 °C for 4 h to prepare a gel electrolyte; a stretchable linear hydrogel electrode with a diameter of 100 μm and a length of 8 cm was taken Two, two electrodes are immersed in the gel electrolyte and taken out, and then assembled into an all-gel supercapacitor with a helical wire-like structure.

The electrochemical activity was characterized by cyclic voltammetry (CV) and galvanostatic charge-discharge (GCD), as shown in Figure 9 and Figure 10, respectively. 9 is a cyclic voltammetry diagram of the stretchable linear all-gel supercapacitor prepared in Example 3 of the present invention. It can be seen from Fig. 9 that the shapes of the CV curves remain rectangular-like when the scanning speed is from 20 mV s ^-1 to 200 mV s ^-1 . 10 is a galvanostatic charge-discharge curve diagram of the stretchable supercapacitor prepared in Example 3 of the present invention. It can be seen from Figure 10 that the current density is from 5 mA g ^-1 to 25 mA g ^-1 , the GCD curve is triangular in shape, and the currents at 20 mA g ^-1 , 50 mA g ^-1 , 100 mA g ^-1 are calculated The mass specific capacitances at density are 1255 mF g ^-1 , 975 mF g ^-1 , and 575 mF g ^-1 , respectively.

The above-mentioned embodiments merely illustrate the principles and effects of the present invention, but are not intended to limit the present invention. Anyone skilled in the art can modify or change the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or changes made by those with ordinary knowledge in the technical field without departing from the spirit and technical idea disclosed in the present invention should still be covered by the claims of the present invention.

Claims (8)

1. The stretchable linear full-gel supercapacitor is characterized by comprising hydrogel electrodes and gel electrolyte, wherein the hydrogel electrodes are wound in a spiral linear manner, and the gel electrolyte is attached to the surfaces of the hydrogel electrodes; the hydrogel electrode is obtained by a cross-linking reaction of a conductive polymer and an additive, wherein the additive is one or more of dimethyl sulfoxide, ethylene glycol, polyethylene glycol p-isooctyl phenyl ether, sodium dodecyl sulfate, sodium dodecyl benzene sulfonate and a fluorine surfactant.

2. The stretchable linear full-gel supercapacitor according to claim 1, wherein the conductive polymer is one or more of polythiophene, polypyrrole and polyaniline.

3. The stretchable linear full-gel supercapacitor according to claim 1, wherein the gel electrolyte is an organic electrolyte.

4. The method for preparing the stretchable linear full-gel supercapacitor according to claim 1, comprising the steps of:

(1) adding an additive into a conductive polymer, and stirring to obtain a conductive polymer mixed solution;

(2) heating the prepared conductive polymer mixed solution to induce physical crosslinking to prepare conductive hydrogel;

(3) preparing the prepared conductive hydrogel into a linear hydrogel electrode;

(4) and soaking the prepared hydrogel electrode with gel electrolyte, and mutually winding the gel electrolyte into a spiral full-gel supercapacitor.

5. The preparation method of the stretchable linear full-gel supercapacitor according to claim 4, wherein the mass of the additive in the step (1) is 1-40% of the conductive polymer mixed solution.

6. The method for preparing the stretchable linear full-gel supercapacitor according to claim 4, wherein the heating temperature in the step (2) is 25-130 ℃.

7. The preparation method of the stretchable linear full-gel supercapacitor according to claim 4, wherein the heating time in the step (2) is 1-24 h.

8. The method for preparing the stretchable linear full-gel supercapacitor according to claim 4, wherein the step (3) is specifically prepared by one or more of 3D printing, wet spinning and physical separation.

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