CN114058060B

CN114058060B - Conductive polymer hydrogel, preparation method thereof and power generating device

Info

Publication number: CN114058060B
Application number: CN202010781134.7A
Authority: CN
Inventors: 魏迪; 周亚宁; 张丽娟; 柳絮; 钟梦娟; 王杨俭; 杨露; 李科
Original assignee: Beijing Graphene Institute BGI
Current assignee: Beijing Graphene Institute BGI
Priority date: 2020-08-06
Filing date: 2020-08-06
Publication date: 2023-06-16
Anticipated expiration: 2040-08-06
Also published as: CN114058060A

Abstract

The invention provides a conductive polymer hydrogel, a preparation method thereof and an electricity generating device applying the conductive polymer hydrogel, wherein the preparation method of the conductive polymer hydrogel comprises the following steps: mixing the hydrogel precursor with short-chain cellulose, and heating and stirring to obtain a mixed solution; performing freezing-tempering circulation treatment on the mixed solution to obtain hydrogel; and soaking the hydrogel in a salt solution to obtain the conductive polymer hydrogel. The method can prepare the conductive polymer hydrogel with higher mechanical strength and good electrical property, and the electricity generating device prepared by adopting the conductive polymer hydrogel has the advantages of adjustable electricity generating quantity, spontaneous electricity generation, green and safe and the like, and meanwhile, the electricity generating device is small in size, light in weight and convenient to carry, can be used as a novel high-performance capacity device, and has good application prospect.

Description

Conductive polymer hydrogel, preparation method thereof and power generating device

Technical Field

The invention relates to the technical field of functional materials, in particular to a conductive polymer hydrogel, a preparation method thereof and an electric device.

Background

With the arrival of energy crisis and the increasing severity of environmental pollution, the development and utilization of green and clean energy become research hotspots for domestic and foreign scholars. The conversion of energy (such as solar energy, waste heat energy, concentration energy and the like) which is widely existing in the nature but cannot be directly utilized into electric energy which can be directly applied generates great economic and social benefits. At present, functional devices such as solar cells and thermoelectric modules are correspondingly developed, and corresponding energy is obtained from the nature and converted into electric energy. However, the widespread use of such devices is limited by environmental constraints.

Water and water vapor are more common and less environmentally constrained than other substances. For example, the difference in salt content between seawater and fresh water is used to obtain electric energy by the osmosis of selective ions through a membrane. The water or saline solution is utilized to flow directionally on the surface of the carbon nano tube foam so as to obtain electric energy. The electric energy can also be obtained by the action of water vapor and the surface of the polymer film rich in the ionic liquid. However, the method is generally limited by the flow of the solution, the power generation amount can not be regulated and controlled, the usable times are low, the duration is short, the used materials are expensive, or the problem of leakage of the aqueous solution exists, so that the method is not suitable for large-scale preparation and wide application.

The conductive polymer hydrogel has a cross-linked three-dimensional network structure, has larger liquid absorption and retention performance and moldability, can be cast into any required shape such as a film without depending on a surfactant or a template, and is suitable for preparing novel energy-producing devices with small volume, light weight and convenient carrying. However, the current conductive polymer hydrogel has low mechanical strength, and the selectable materials are very limited, so that development of a new high-strength material system for constructing a high-performance power generation device with green safety, adjustable power generation amount, multiple use times and long use time is urgently needed.

It is noted that the information disclosed in the foregoing background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known to a person of ordinary skill in the art.

Disclosure of Invention

The invention aims to overcome at least one defect of the prior art, and provides a conductive polymer hydrogel, a preparation method thereof and an electricity generating device applying the conductive polymer hydrogel, so as to solve the problems that the existing product device cannot realize electricity generation quantity regulation and control, has high cost or has water solution leakage and the like.

In order to achieve the above purpose, the present invention adopts the following technical scheme:

the invention provides a preparation method of conductive polymer hydrogel, which comprises the following steps: mixing the hydrogel precursor with short-chain cellulose, and heating and stirring to obtain a mixed solution; performing freezing-tempering circulation treatment on the mixed solution to obtain hydrogel; and soaking the hydrogel in a salt solution to obtain the conductive polymer hydrogel.

According to one embodiment of the invention, the hydrogel precursor is selected from one or more of polyvinyl alcohol and derivatives thereof, including one or more of chitosan-polyvinyl alcohol, polyacrylic acid-polyvinyl alcohol, gelatin-polyvinyl alcohol and cyclodextrin-polyvinyl alcohol; the short-chain cellulose is selected from one or more of hydroxypropyl cellulose, hydroxyethyl cellulose, hydroxymethyl cellulose and carboxymethyl cellulose, the mass ratio of the short-chain cellulose to the hydrogel precursor is 1:5-1:10, and the heating and stirring temperature is 60-90 ℃.

According to one embodiment of the invention, the method further comprises the step of standing the mixed solution for 12-24 hours at room temperature before the cyclic treatment.

According to one embodiment of the invention, the number of cycles is at least 2, each cycle comprising: freezing the mixed solution at-15 to-40 ℃ for 10 to 24 hours, and then returning the mixed solution to room temperature for 10 to 24 hours.

According to one embodiment of the invention, the salt solution is selected from one or more of sodium chloride solution, potassium hydroxide solution, magnesium chloride solution, copper chloride solution, zinc nitrate solution and ferric oxide solution, the concentration of the salt solution is 0.01 mol/L-5 mol/L, and the soaking treatment time is 10 h-24 h.

The invention also provides a conductive polymer hydrogel which is prepared by adopting the method.

The invention also provides an electricity generating device, comprising: a flexible substrate, first and second electrodes, and first and second hydrogels, wherein the flexible substrate has first and second portions; the first electrode and the second electrode are arranged on the same side surface of the flexible substrate and are respectively positioned at the first part and the second part; the first hydrogel and the second hydrogel are respectively covered on the surfaces of the first electrode and the second electrode and are fixedly connected with the substrate; the first hydrogel and the second hydrogel are both conductive polymer hydrogels, and the first hydrogel and the second hydrogel have different conductive ion concentrations; wherein the power generating device is configured to generate electrical energy by bending the flexible substrate such that the first portion and the second portion are opposed such that the first hydrogel and the second hydrogel are in contact.

According to one embodiment of the invention, the shape of the first hydrogel and the second hydrogel is each independently selected from a cylinder, a cuboid or a cube; when the shapes of the first hydrogel and the second hydrogel are cylinders, the diameter of the cylinders is 0.1 mm-15 mm, and the height is not more than 5mm; the first hydrogel and the second hydrogel have a difference in concentration of conductive ions of at least 0.01mol/L.

According to one embodiment of the present invention, the flexible substrate is selected from one or more of polyethylene terephthalate film, polyvinyl chloride film, polyimide film, polyester film, polypropylene film, polytetrafluoroethylene film, and polyester resin film.

According to one embodiment of the invention, the first electrode has a width of 2mm to 10mm and a length of 2mm to 20mm; the width of the second electrode is 2 mm-10 mm, and the length is 2 mm-20 mm; the materials of the first electrode and the second electrode are respectively and independently selected from one or more of inorganic conductive materials and metal conductive materials, and the distance between the first electrode and the second electrode is 5 mm-50 mm.

According to the technical scheme, the beneficial effects of the invention are as follows:

the invention provides a novel conductive polymer hydrogel and a preparation method thereof. According to the method, ion-rich pores are introduced into a strong hydrogel matrix, and the salting-out effect is utilized, so that the conductive polymer hydrogel with higher mechanical strength and good electrical property can be prepared. The prepared electricity generating device has the advantages of spontaneously generating electric energy, no need of extra charging process and green and safe performance by utilizing the liquid absorption and retention performance of the conductive polymer hydrogel and the concentration difference between the liquid absorption and retention performance of the conductive polymer hydrogel. Meanwhile, the control of the electricity generation amount can be realized according to the concentration of the salt solution, the shape and thickness of the gel, and the like, and the device can be freely assembled according to the requirement. The power generating device has small volume, light weight and convenient carrying, can be used as a novel high-performance capacity device, and has good application prospect.

Drawings

The following drawings are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate the invention and together with the description serve to explain the invention, without limitation to the invention.

FIG. 1 is a flow chart of a process for preparing a conductive polymer hydrogel according to an embodiment of the present invention;

FIG. 2 is a schematic view of a process for preparing a conductive polymer hydrogel according to an embodiment of the present invention;

fig. 3 is a schematic view showing a structure of an unfolded state of a power generating device according to an embodiment of the present invention;

fig. 4 is a schematic diagram of a long electric device in a folded state according to an embodiment of the present invention;

FIG. 5 is a graph of impedance testing of the power generating device of example 1;

fig. 6 is a graph of open circuit voltage testing of the power generating device of example 1.

Wherein reference numerals are as follows:

100: container

200: water bath kettle

300: hydrogel

400: conductive polymer hydrogels

501: first hydrogel

502: second hydrogel

600: flexible substrate

701: first electrode

702: second electrode

I: first part

II: second part

d: spacing of

Detailed Description

The following provides various embodiments or examples to enable those skilled in the art to practice the invention as described herein. These are, of course, merely examples and are not intended to limit the invention from that described. The endpoints of the ranges and any values disclosed in the present invention are not limited to the precise range or value, and the range or value should be understood to include values close to the range or value. For numerical ranges, one or more new numerical ranges may be found between the endpoints of each range, between the endpoint of each range and the individual point value, and between the individual point value, in combination with each other, and should be considered as specifically disclosed herein.

Fig. 1 is a process flow chart of a preparation process of a conductive polymer hydrogel according to an embodiment of the present invention, and fig. 2 is a schematic view of a preparation process of a conductive polymer hydrogel according to an embodiment of the present invention, and, as shown in combination with fig. 1 and 2, a preparation method of a conductive polymer hydrogel according to the present invention includes: mixing the hydrogel precursor with short-chain cellulose, and heating and stirring to obtain a mixed solution; performing freezing-tempering circulation treatment on the mixed solution to obtain hydrogel; and soaking the hydrogel in a salt solution to obtain the conductive polymer hydrogel.

According to the invention, the development and construction of the green environment-friendly high-performance power generation device have important economic value and social significance, and the electric energy is obtained by utilizing the salt difference of the seawater and the fresh water and through the permeation of selective ion permeation membranes. However, the method is generally limited by the flow of the solution, the power generation amount can not be regulated and controlled, the usable times are low, the duration is short, the used materials are expensive, or the problem of leakage of the aqueous solution exists, so that the method is not suitable for large-scale preparation and wide application. The inventor of the invention discovers that by introducing ion-rich pores into a strong hydrogel matrix and utilizing salting-out effect, conductive polymer hydrogel with higher mechanical strength and electrical property can be prepared, and by utilizing the liquid absorption and retention properties and concentration difference between the conductive polymer hydrogel, a high-performance power generating device which can control electric quantity, is small, exquisite, light, green and safe can be prepared.

Specifically, the method comprises the steps of firstly selecting high-strength polyvinyl alcohol or derivatives thereof as a matrix material, introducing high-performance short-chain cellulose, then introducing conductive ions through salting out action and causing wrinkles, so that the volume is contracted, and the modulus is increased. The porous structure with good distribution and ion migration generate ion-rich environment for embedded high-performance short-chain cellulose, so that the ion conductivity of the hydrogel is greatly improved, and the structural stability and electrochemical performance of the obtained conductive polymer hydrogel are greatly improved.

The method for preparing the conductive polymer hydrogel of the present invention is specifically described below with reference to fig. 1 and 2.

As shown in fig. 2, first, a hydrogel precursor and short-chain cellulose are mixed and placed in a container 100, and then the container 100 is placed in a water bath 200, and the mixture is obtained after heating and stirring in a constant-temperature water bath. Preferably, the method further comprises the step of standing the mixed solution at room temperature for 12-24 hours, for example, 12 hours, 13 hours, 16 hours, 18 hours, 20 hours, 21 hours and the like, before the circulating treatment, so as to remove residual bubbles in the mixed solution.

The hydrogel precursor can be one or more of polyvinyl alcohol (PVA) and derivatives thereof, wherein the derivatives are one or more of chitosan-polyvinyl alcohol, polyacrylic acid-polyvinyl alcohol, gelatin-polyvinyl alcohol and cyclodextrin-polyvinyl alcohol, preferably high-strength polyvinyl alcohol, and the polyvinyl alcohol has a polymerization degree of 1750-1799 and an alcoholysis degree of 85-99%. The short chain cellulose can be one or more of hydroxypropyl cellulose, hydroxyethyl cellulose, hydroxymethyl cellulose and carboxymethyl cellulose.

In some embodiments, the aforementioned mass ratio of short-chain cellulose to hydrogel precursor is 1:5-1:10, e.g., 1:5, 1:6, 1:7, 1:8, 1:9, etc., and the temperature of the heating and stirring is 60 ℃ to 90 ℃, e.g., 60 ℃, 70 ℃, 80 ℃, 85 ℃, etc. Taking hydrogel precursors as polyvinyl alcohol as an example, by mixing short-chain cellulose into the polyvinyl alcohol under the specific conditions, embedding short-chain fibers into a strong gel matrix, reducing the gel matrix crosslinking density, the physical crosslinking type polyvinyl alcohol-short-chain fiber hydrogel can be prepared, and water-rich pores are formed.

Then, the mixed solution obtained above was subjected to a freeze-tempering cycle treatment to obtain hydrogel 300.

Specifically, the mixed solution after standing is subjected to freezing treatment at-15 ℃ to-40 ℃, for example, -15 ℃, -30 ℃, -32 ℃, -40 ℃ and the like for 10-24 hours, for example, 10 hours, 13 hours, 18 hours, 20 hours, 22 hours and the like, and then subjected to tempering at room temperature for 10-24 hours, for example, 10 hours, 12 hours, 18 hours, 21 hours, 23 hours and the like to form 1 freezing-tempering cycle treatment, and then subjected to multiple cycles, wherein the cycle number is not less than 2, preferably 3 or more. In this way, the crystallinity of the polymer can be increased, thereby obtaining the hydrogel 300 having a good porous distribution structure and high mechanical strength.

Further, the hydrogel 300 is immersed in a salt solution 400 to obtain the conductive polymer hydrogel 500 of the present invention.

In some embodiments, the foregoing soaking time is 10h to 24h, e.g., 10h, 12h, 15h, 20h, etc. The salt solution is selected from one or more of sodium chloride solution, potassium hydroxide solution, magnesium chloride solution, copper chloride solution, zinc nitrate solution and ferric oxide solution, and the concentration of the salt solution is 0.01mol/L to 5mol/L, for example, 0.01mol/L, 0.1mol/L, 0.5mol/L, 1mol/L, 2mol/L, 3mol/L, 4.5mol/L, 5mol/L and the like.

The hydrogel is placed in a salt solution for soaking, conductive ions are introduced through salting out and wrinkling is caused, so that the volume is contracted, the modulus is increased, a porous structure with good distribution and ions are migrated to embedded high-performance short-chain cellulose to generate an ion-rich environment, the ion conductivity of the hydrogel is greatly improved, the obtained conductive polymer hydrogel has good mechanical strength, and meanwhile, the electrochemical performance is also improved, and the hydrogel can be further applied to the preparation of an electricity generating device.

Another aspect of the present invention provides an electricity generating device employing the aforementioned electrically conductive polymer hydrogel.

Fig. 3 is a schematic diagram showing a structure of an unfolded state of the power generating device according to an embodiment of the present invention, and fig. 4 is a schematic diagram showing a folded state of the long electric device according to an embodiment of the present invention. The structure, connection manner and functional relationship of the main components of an exemplary embodiment of the power generating device according to the present invention are described in detail with reference to fig. 3 and 4.

As shown in fig. 3, the power generating device of the present invention includes: a flexible substrate 600, first and

second electrodes

701 and 702, and first and

second hydrogels

501 and 502, wherein the flexible substrate 600 has first and second portions I and II; the first electrode 701 and the second electrode 702 are disposed on the same side of the flexible substrate 600 and are respectively located at the first portion I and the second portion II; the first hydrogel 501 and the second hydrogel 502 are respectively covered on the surfaces of the first electrode 701 and the second electrode 702 and are fixedly connected with the substrate 600, so that the first electrode 701 is located between the substrate 600 and the first hydrogel 501, and the second electrode 702 is located between the substrate 600 and the second hydrogel 502. Wherein, the first hydrogel 501 and the second hydrogel 502 are both conductive polymer hydrogels, and the first hydrogel 501 and the second hydrogel 502 have different conductive ion concentrations.

As shown in fig. 4, the first portion I and the second portion II are opposed to each other by bending the flexible substrate 600, so that the first hydrogel 501 and the second hydrogel 502 are in contact, and since the first hydrogel 501 and the second hydrogel 502 are configured to have different concentrations of conductive ions, electric energy can be spontaneously generated by using the concentration differences thereof, thereby realizing an electricity generating function. When the operation is not needed, the flexible substrate 600 can be unfolded and restored to the state shown in fig. 3, so that the contact and separation of the hydrogel are realized through the doubling-up and unfolding of the substrate, and the repeated recycling of the power generating device is realized.

The aforementioned first hydrogel 501 and second hydrogel 502 having different concentrations of conductive ions are achieved by immersing them in salt solutions having different concentrations during the preparation of the hydrogels, for example, after obtaining two hydrogels by freeze-tempering cycle treatment, immersing them in 1mol/L and 5mol/L sodium chloride solution, respectively, thereby obtaining the first hydrogel and second hydrogel having a difference in ion concentration. Of course, the impregnating solution may also be a different kind of salt solution, but it is necessary to ensure that the concentrations of the two are different. Typically, the first hydrogel and the second hydrogel have a difference in concentration of conductive ions of at least 0.01mol/L. The difference of ion concentration difference can realize the control of the electricity generation amount, so the electricity generation device of the invention also has the advantage of controllable adjustment of the electricity generation amount.

In some embodiments, the shapes of the first hydrogel and the second hydrogel are each independently selected from a cylinder, a cuboid or a cube, and other possible shapes may be selected according to actual needs, and the present invention is not limited thereto. As shown in FIG. 3, when the first hydrogel and the second hydrogel are both cylindrical in shape, the diameter of the cylinder is 0.1mm to 15mm, and the height is not more than 5mm. The shape and thickness of the hydrogel are different to directly influence the diffusion and release speed of the conductive solution, so that the electric quantity can be influenced to a certain extent.

In some embodiments, the flexible substrate is selected from one or more of polyethylene terephthalate film, polyvinyl chloride film, polyimide film, polyester film, polypropylene film, polytetrafluoroethylene film, and polyester resin film. The difference of the flexible substrate can cause the difference of the adhesion capability of the hydrogel and the hydrogel, so that in actual use, different fastening modes can be selected according to the difference of the flexible substrate, so that the hydrogel can be tightly connected with the substrate, and falling off during doubling can be avoided. In addition, in order to avoid the adhesion between the first hydrogel 501 and the second hydrogel 502 after the substrate is folded in half, which may affect the recycling of the device, a thin film may be optionally disposed on the first hydrogel 501 or the second hydrogel 502, where the thin film does not affect the ion transmission between the two, and at the same time, can avoid the adhesion between the two.

The first electrode and the second electrode are respectively used as a positive electrode and a negative electrode, the materials of the first electrode and the second electrode are respectively and independently selected from one or more of inorganic conductive materials and metal conductive materials, and the first electrode and the second electrode can be printed on the flexible substrate in a screen printing mode. The distance d between the first electrode and the second electrode is 5mm to 50mm, for example, 5mm, 15mm, 25mm, 30mm, 40mm, 45mm, etc. The first electrode has a width of 2mm to 10mm, for example, 2mm, 5mm, 7mm, 8mm, 9mm, 10mm, etc., and a length of 2mm to 20mm, for example, 2mm, 4mm, 7mm, 8mm, 12mm, 15mm, etc.; the width of the second electrode is 2mm to 10mm, for example, 2mm, 6mm, 8mm, 9mm, 10mm, etc., and the length is 2mm to 20mm, for example, 2mm, 4mm, 6mm, 7mm, 9mm, 15mm, etc.; preferably, the first electrode and the second electrode are identical in length and width.

In summary, the invention provides a method for preparing conductive polymer hydrogel with higher mechanical strength and electrical property by introducing ion-rich pores into a strong hydrogel matrix and utilizing salting-out effect. The programmable power generation device is prepared by utilizing the liquid absorption and retention properties of the conductive polymer hydrogel and the concentration difference between the liquid absorption and retention properties of the conductive polymer hydrogel, and can adjust the power generation amount according to the needs, automatically generate electric energy, do not need to carry out an additional charging process, and are green and safe. The electric generating device adopts the conductive polymer hydrogel, and realizes hydrogel contact and separation through the doubling-up and unfolding of the substrate, so that the electric generating device can be recycled for multiple times. Meanwhile, the power generating device can realize power generation control according to the concentration of salt solution, the shape and thickness of gel, and the like, and can be freely assembled according to requirements. The moldability of the conductive polymer hydrogel, the shape following property of the flexible matrix and the printability of the electrode can realize the preparation of a novel capacity device which has small volume, light weight and convenient carrying, and has good application prospect.

The invention will be further illustrated by the following examples, but the invention is not limited thereby. The reagents, materials, etc. used in the present invention are commercially available unless otherwise specified.

Example 1

1) 0.5g of hydroxypropyl cellulose was dissolved in a mixed solvent of 4.5ml of dimethyl sulfoxide and 9ml of water, stirred for 10 minutes, then heated in a water bath at 70℃and stirred until the hydroxypropyl cellulose was completely dissolved. 3.2g of polyvinyl alcohol (polymerization degree 1788, alcoholysis degree 87% -89%) was added to the above solution, and heated to 90℃to dissolve all the polyvinyl alcohol powder completely. The stirring was then continued for 3 hours with heating, and a hydroxypropylcellulose-polyvinyl alcohol solution was finally obtained.

2) The above solution was poured into a mold to be cooled to room temperature and allowed to stand at room temperature for 12 hours, eliminating bubbles formed during stirring. The left solution was frozen at-20℃for 12 hours, and then thawed at room temperature for 3 hours. The above freeze-thawing process was cycled three times to obtain a solid hydroxypropyl cellulose-polyvinyl alcohol gel.

3) And respectively soaking the hydroxypropyl cellulose-polyvinyl alcohol hydrogel into 1mol/L and 5mol/L sodium chloride solution for 12 hours until the ion exchange in water and salt solution reaches equilibrium, so as to obtain the conductive polymer hydrogel.

4) The same silver electrode is printed on polyethylene terephthalate film (PET) by screen printing method, the electrode width x length is 2 x 10mm, and the distance between two electrodes is 15mm. Two conductive polymer hydrogels are made into cylindrical thin sheets with the diameter of 13mm and the height of 3mm, and the cylindrical thin sheets are respectively used as positive electrodes and negative electrodes to be fastened and placed at the two electrodes to form the power generation device. The PET film is folded in half so that the two conductive polymer hydrogels are in front contact to generate electrical energy. The electrical signal testing instrument was connected to the electrodes with wires and the measured impedance profile was shown in fig. 5 with ion mobility of about 2.8 x 10 ^-4 S/cm. The open circuit voltage results are shown in fig. 6, where the open circuit voltage is about 0.2V, indicating that there is electrical energy generation.

Example 2

1) 0.5g of hydroxypropyl cellulose was dissolved in a mixed solvent of 4.5ml of dimethyl sulfoxide and 9ml of water, stirred for 10 minutes, then heated in a water bath at 70℃and stirred until the hydroxypropyl cellulose was completely dissolved. 3.2g of polyvinyl alcohol (polymerization degree 1788, alcoholysis degree 87% -89%) was added to the above solution, and heated to 90℃to dissolve all the polyvinyl alcohol powder completely. The stirring was then continued for 3 hours with heating, and a hydroxypropylcellulose-polyvinyl alcohol solution was finally obtained. The above solution was poured into a mold to be cooled to room temperature and allowed to stand at room temperature for 12 hours, eliminating bubbles formed during stirring.

2) The left solution was frozen at-20℃for 12 hours, and then thawed at room temperature for 3 hours. The above freeze-thawing process was cycled three times to obtain a solid hydroxypropyl cellulose-polyvinyl alcohol gel.

3) And respectively soaking the hydroxypropyl cellulose-polyvinyl alcohol hydrogel into sodium chloride solution with the concentration of 1mol/L and 4mol/L for 12 hours until the ion exchange reaches equilibrium, so as to obtain the final conductive polymer hydrogel.

4) The same silver electrode is printed on polyethylene terephthalate film (PET) by screen printing method, the electrode width x length is 2 x 10mm, and the distance between two electrodes is 15mm. Two conductive polymer hydrogels are made into a cylindrical sheet with the diameter of 13mm and the height of 3mm, and the cylindrical sheet is respectively used as positive and negative electrodes to be fastened and placed at the two electrodes to form the power generation device. The PET film is folded in half so that the two conductive polymer hydrogels are in front contact to generate electrical energy. The electrical signal testing instrument was connected to the electrode with a wire to measure ion mobility of about 2.5X10 ^-4 S/cm, open circuit voltage of about 0.17V, indicating electrical energy generation.

Example 3

3) And respectively soaking the hydroxypropyl cellulose-polyvinyl alcohol hydrogel into sodium chloride solution with the concentration of 1mol/L and 3mol/L for 12 hours until the ion exchange reaches equilibrium, so as to obtain the final conductive polymer hydrogel.

4) The same silver electrode is printed on polyethylene terephthalate film (PET) by screen printing method, the electrode width x length is 2 x 10mm, and the distance between two electrodes is 15mm. Two conductive polymer hydrogels were formed into a circle with a diameter of 13mm and a height of 3mmAnd the column sheet is respectively used as positive and negative electrodes to be fastened and arranged at the two electrodes to form the power generation device. The PET film is folded in half so that the two conductive polymer hydrogels are in front contact to generate electrical energy. Electrical signal testing apparatus was connected to the electrodes with wires and the measured ion mobility was approximately 2.2X10 ^-4 S/cm. The measured open circuit voltage was about 0.12V, indicating that electrical energy was being produced.

Example 4

1) 0.1g of hydroxyethyl cellulose was dissolved in a mixed solvent of 0.9ml of dimethyl sulfoxide and 3ml of water, stirred for 10 minutes, then heated in a water bath at 70℃and stirred until the hydroxypropyl cellulose was completely dissolved. 0.64g of polyvinyl alcohol (polymerization degree 1788, alcoholysis degree 87% -89%) was added to the above solution, and the solution was heated to 90℃to completely dissolve all the polyvinyl alcohol powder. The stirring was then continued for 3 hours with heating, and a hydroxypropylcellulose-polyvinyl alcohol solution was finally obtained. The above solution was poured into a mold, cooled to room temperature and allowed to stand at room temperature for 12 hours, eliminating bubbles formed during stirring.

2) The solution after standing was frozen at-20℃for 12 hours, and then allowed to stand at room temperature for thawing for 3 hours. The above freeze-thawing process was cycled three times to obtain a solid hydroxypropyl cellulose-polyvinyl alcohol gel.

3) And respectively soaking the hydroxyethyl cellulose-polyvinyl alcohol gel into sodium chloride solution with the concentration of 1mol/L and 5mol/L for 12 hours until the ion exchange reaches equilibrium, so as to obtain the final gel electrolyte.

4) The same silver electrode is printed on polyethylene terephthalate film (PET) by screen printing method, the electrode width x length is 2 x 10mm, and the distance between two electrodes is 15mm. The conductive polymer hydrogel with the concentration of sodium chloride solution of 1mol/L and 5mol/L is manufactured into a cylindrical sheet with the diameter of 13mm and the height of 3mm, and the cylindrical sheet is respectively used as positive and negative electrodes to be fastened and placed at the two electrodes to form the power generation device. The PET film is folded in half so that the two conductive polymer hydrogels are in front contact to generate electrical energy. Electrical signal testing apparatus was connected to the electrodes with wires and the measured ion mobility was about 2.7X10 ^-4 S/cm, the measured open circuit voltage was about 0.176V, indicating electrical energy generation.

In summary, the invention provides a novel conductive polymer hydrogel and a preparation method thereof, and a novel electricity generating device is prepared by applying the conductive polymer hydrogel. The preparation process of the conductive polymer hydrogel is simple and low in cost, and wrinkles are formed on the surface of a gel matrix by utilizing the salting-out effect between the saline solution and the aqueous solution, so that the volume is shrunk, the modulus is increased, and the structural stability and the electrochemical performance of the obtained hydrogel are remarkably improved. When the conductive polymer hydrogel is applied to an electricity generating device, the conductive polymer hydrogel can automatically generate electric energy by utilizing the liquid absorption and liquid retention property of the conductive polymer hydrogel and the concentration difference between the liquid absorption and liquid retention property of the conductive polymer hydrogel, so that the conductive polymer hydrogel is green and safe; the hydrogel is contacted and separated through the doubling and unfolding of the substrate, so that the power generating device can be recycled for multiple times; meanwhile, the electricity generation amount can be controlled according to the concentration of the salt solution, the shape and thickness of the gel, and the like, so that the device can be freely assembled according to requirements. The power generating device has small volume, light weight and convenient carrying, can be used as a novel high-performance capacity device, and has good application prospect.

It will be appreciated by persons skilled in the art that the embodiments described herein are merely exemplary and that various other alternatives, modifications and improvements may be made within the scope of the invention. Thus, the present invention is not limited to the above-described embodiments, but only by the claims.

Claims

1. An electricity generating device, comprising:

a flexible substrate having a first portion and a second portion;

the first electrode and the second electrode are arranged on the same side face of the flexible substrate and are respectively positioned at the first part and the second part; a kind of electronic device with high-pressure air-conditioning system

The first hydrogel and the second hydrogel are respectively covered on the surfaces of the first electrode and the second electrode and are fixedly connected with the substrate; the first hydrogel and the second hydrogel are conductive polymer hydrogels, and the first hydrogel and the second hydrogel have different conductive ion concentrations;

wherein the power generating device is configured to cause the first and second portions to oppose each other by bending the flexible substrate so that the first and second hydrogels are in contact to generate electrical energy;

the preparation method of the conductive polymer hydrogel comprises the following steps:

mixing the hydrogel precursor with short-chain cellulose, and heating and stirring to obtain a mixed solution;

performing freezing-tempering circulation treatment on the mixed solution to obtain hydrogel; a kind of electronic device with high-pressure air-conditioning system

Soaking the hydrogel in a salt solution to obtain the conductive polymer hydrogel;

the hydrogel precursor is selected from one or more of polyvinyl alcohol and derivatives thereof, and the derivatives are selected from one or more of chitosan-polyvinyl alcohol, polyacrylic acid-polyvinyl alcohol, gelatin-polyvinyl alcohol and cyclodextrin-polyvinyl alcohol; the short-chain cellulose is selected from one or more of hydroxypropyl cellulose, hydroxyethyl cellulose, hydroxymethyl cellulose and carboxymethyl cellulose, the mass ratio of the short-chain cellulose to the hydrogel precursor is 1:5-1:10, and the temperature of heating and stirring is 60-90 ℃;

the concentration of the salt solution is 0.01 mol/L-5 mol/L, and the soaking treatment time is 10-24 hours;

the first hydrogel and the second hydrogel have a difference in concentration of conductive ions of at least 0.01mol/L.

2. The power generating device of claim 1, further comprising a step of standing the mixed solution at room temperature for 12-24 hours before the cyclic treatment.

3. The power generating device of claim 1, wherein the number of cycles is at least 2, each cycle comprising: and (3) freezing the mixed solution at the temperature of minus 15 ℃ to minus 40 ℃ for 10 hours to 24 hours, and then returning the mixed solution at the room temperature for 10 hours to 24 hours.

4. The power generating device of claim 1, wherein the salt solution is selected from one or more of a sodium chloride solution, a potassium hydroxide solution, a magnesium chloride solution, a copper chloride solution, a zinc nitrate solution, and a ferric oxide solution.

5. The product device of claim 1, wherein the shape of the first hydrogel and the second hydrogel are each independently selected from a cylinder, a cuboid, or a cube; when the shapes of the first hydrogel and the second hydrogel are cylinders, the diameter of each cylinder is 0.1 mm-15 mm, and the height of each cylinder is not more than 5mm.

6. The product device of claim 1, wherein the flexible substrate is selected from one or more of polyethylene terephthalate film, polyvinyl chloride film, polyimide film, polypropylene film, and polytetrafluoroethylene film.

7. The product device of claim 1, wherein the first electrode has a width of 2mm to 10mm and a length of 2mm to 20mm; the width of the second electrode is 2 mm-10 mm, and the length of the second electrode is 2 mm-20 mm; the materials of the first electrode and the second electrode are respectively and independently selected from one or more of inorganic conductive materials and metal conductive materials, and the distance between the first electrode and the second electrode is 5 mm-50 mm.