CN113932950A - Flexible pressure sensor and manufacturing method thereof - Google Patents
Flexible pressure sensor and manufacturing method thereof Download PDFInfo
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- CN113932950A CN113932950A CN202111193029.2A CN202111193029A CN113932950A CN 113932950 A CN113932950 A CN 113932950A CN 202111193029 A CN202111193029 A CN 202111193029A CN 113932950 A CN113932950 A CN 113932950A
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Images
Classifications
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
- G01L1/00—Measuring force or stress, in general
- G01L1/14—Measuring force or stress, in general by measuring variations in capacitance or inductance of electrical elements, e.g. by measuring variations of frequency of electrical oscillators
- G01L1/142—Measuring force or stress, in general by measuring variations in capacitance or inductance of electrical elements, e.g. by measuring variations of frequency of electrical oscillators using capacitors
- G01L1/146—Measuring force or stress, in general by measuring variations in capacitance or inductance of electrical elements, e.g. by measuring variations of frequency of electrical oscillators using capacitors for measuring force distributions, e.g. using force arrays
Abstract
A flexible pressure sensor and a method of making the same are provided. The flexible pressure sensor includes: a flexible electrode; a composite dielectric film disposed on the flexible electrode; the high dielectric constant adhesive layer is coated on the composite dielectric film; and the foam porous electrode is covered on the high dielectric constant adhesive layer. According to the invention, the composite film with high dielectric constant is used as the dielectric layer, so that the capacitance variation of the flexible pressure sensor can be obviously improved, and the sensitivity of the flexible pressure sensor is improved; meanwhile, the influence of parasitic capacitance and electromagnetic interference on the working stability of the flexible pressure sensor is reduced due to the increase of the capacitance, and the anti-interference capability is improved.
Description
Technical Field
The invention belongs to the technical field of sensors, and particularly relates to a flexible pressure sensor and a manufacturing method thereof.
Background
Compared with the traditional pressure sensor, the Flexible Pressure Sensor (FPS) can easily realize pressure detection on a curved object, is particularly suitable for measuring the pressure distributed on the surface of a human body, and is widely applied to the fields of robot electronic skin, human health detection, human-computer interaction and the like. Pressure sensors can be classified into piezoresistive, capacitive and piezoelectric pressure sensors according to the types of measurement signals, wherein the capacitive pressure sensor has the characteristics of low power consumption, high precision and good dynamic response, and is suitable for being applied to mobile electronic equipment and occasions with higher precision requirements.
However, the existing flexible capacitive pressure sensor has low sensitivity and a small detection range, and is easily affected by electromagnetic interference and parasitic capacitance, so how to improve the sensitivity of the sensor is a technical problem that needs to be solved urgently.
Disclosure of Invention
In order to solve the technical problems in the prior art, according to an embodiment of the present invention, a flexible pressure sensor with high sensitivity and high interference capability and a manufacturing method thereof are provided.
According to an aspect of an embodiment of the present invention, there is provided a flexible pressure sensor including: a flexible electrode; a composite dielectric film disposed on the flexible electrode; the high-dielectric-constant adhesive layer is coated on the composite dielectric film; and the foam porous electrode is covered on the high dielectric constant adhesive layer.
In one example of the flexible pressure sensor provided in the above aspect, the composite dielectric thin film is formed of a polymer host material and a reinforcing phase material, wherein a filling mass fraction of the reinforcing phase material is 1% to 10%.
In one example of the flexible pressure sensor provided in the above aspect, the material of the foam porous electrode is an aerogel conductive material, and the porosity of the aerogel conductive material is 0.1% to 2%; or the foam porous electrode is made of a conductive material with a polymer foam framework as a main body, and the porosity of the conductive material with the polymer foam framework as the main body is 2-20%.
In one example of the flexible pressure sensor provided in the above aspect, the high dielectric constant adhesive layer has a dielectric constant of more than 100.
According to another aspect of the embodiments of the present invention, there is provided a method for manufacturing a flexible pressure sensor, including: fixing the prepared and formed composite dielectric film on a flexible electrode; coating the prepared and formed high-dielectric-constant adhesive layer on the composite dielectric film; and covering the manufactured and formed foam porous electrode on the high dielectric constant adhesive layer.
In one example of the method of manufacturing a flexible pressure sensor provided in another aspect above, the method of manufacturing a flexible pressure sensor includes: selecting proper nano functional materials to carry out surface modification and purification in sequence to obtain an enhanced phase material; and preparing the reinforced phase material and the selected polymer main body material into a solution, and obtaining the composite dielectric film in a solution film casting mode.
In one example of the method for manufacturing the flexible pressure sensor provided by the another aspect, the method for performing surface modification on the nano-functional material includes in-situ polymerization, diazotization, surface molecular grafting and stabilizer addition; the method for purifying the surface-modified nano functional material comprises the step of separating and purifying the surface-modified nano functional material in a centrifugation and low-temperature freeze-drying manner to obtain the enhanced phase material.
In an example of the method for manufacturing a flexible pressure sensor provided in another aspect, the method for obtaining the composite dielectric thin film by solution casting a film by formulating the reinforcing phase material and the selected polymer host material into a solution includes: adding a solvent into the enhanced phase material to prepare a dispersion liquid, and carrying out ultrasonic treatment on the dispersion liquid; adding the selected polymer main material into the dispersion liquid after ultrasonic treatment, stirring and dissolving, adding the film-forming aid, and coating the dispersion liquid added with the film-forming aid by an automatic film coating machine; and sequentially carrying out heating treatment and drying treatment on the coated dispersion liquid to obtain the composite dielectric film.
In one example of the method for manufacturing a flexible pressure sensor provided in another aspect above, the method for manufacturing the foam porous electrode includes: the foam porous electrode formed into the aerogel conductive material is manufactured by adopting a colloid solution freeze-drying method, or the selected conductive material with the macromolecular foam framework as a main body is subjected to roughening or hydrophilic surface treatment, and the foam porous electrode is manufactured and formed by adopting an electroless deposition or solution impregnation method.
In one example of the method for manufacturing a flexible pressure sensor provided in another aspect above, the high-k adhesive layer has a dielectric constant greater than 100.
Has the advantages that: according to the invention, the composite film with high dielectric constant is used as the dielectric layer, so that the capacitance variation of the flexible pressure sensor can be obviously improved, and the sensitivity of the flexible pressure sensor is improved; meanwhile, the influence of parasitic capacitance and electromagnetic interference on the working stability of the flexible pressure sensor is reduced due to the increase of the capacitance, and the design cost of an ADC circuit and the like is reduced. In addition, the three-dimensional porous foam electrode is also adopted as the counter electrode of the capacitance sensor, so that the change of the polar plate distance of the sensor can be acted on the porous electrode, the bifurcation structure of the porous electrode contacting with the dielectric medium is easy to deform under low pressure, the low-pressure sensitivity is obviously improved, the polar plate distance of the capacitance formed by the porous electrode is continuously reduced under medium and high pressure, the ultrahigh dielectric constant of the dielectric layer enables the sensor to have larger capacitance change, and the detection in a wide pressure range can be realized.
Drawings
The above and other aspects, features and advantages of embodiments of the present invention will become more apparent from the following description taken in conjunction with the accompanying drawings, in which:
FIG. 1 is a schematic structural diagram of a flexible pressure sensor according to an embodiment of the present invention;
FIG. 2 is a flow chart of a method of making a flexible pressure sensor according to an embodiment of the present invention;
FIG. 3 shows a graph comparing the performance of a flexible pressure sensor using pure TPU and MXene/TPU composite materials as the dielectric layer;
fig. 4 is a diagram of pulse wave signals obtained by measuring the pulse pressure of a human body using a flexible pressure sensor according to an embodiment of the present invention.
Detailed Description
Hereinafter, specific embodiments of the present invention will be described in detail with reference to the accompanying drawings. This invention may, however, be embodied in many different forms and should not be construed as limited to the specific embodiments set forth herein. Rather, these embodiments are provided to explain the principles of the invention and its practical application to thereby enable others skilled in the art to understand the invention for various embodiments and with various modifications as are suited to the particular use contemplated.
As used herein, the term "include" and its variants mean open-ended terms in the sense of "including, but not limited to. The terms "based on," based on, "and the like mean" based at least in part on, "" based at least in part on. The terms "one embodiment" and "an embodiment" mean "at least one embodiment". The term "another embodiment" means "at least one other embodiment". The terms "first," "second," and the like may refer to different or the same object. Other definitions, whether explicit or implicit, may be included below. The definition of a term is consistent throughout the specification unless the context clearly dictates otherwise.
To solve the technical problems in the background art, a flexible pressure sensor and a method for manufacturing the same are provided according to an embodiment of the present invention. The flexible pressure sensor adopts a conductive foam porous electrode as a pressure-sensitive layer, and is combined with a high-dielectric-constant composite dielectric film to improve the detection interval and sensitivity of the flexible pressure sensor. In addition, the capacitance variation of the composite dielectric film with high dielectric constant can be remarkably increased, and meanwhile, the foam porous electrode enables the electrode displacement of the flexible pressure sensor to be more remarkable under the pressure condition, so that the pressure sensing performance with high sensitivity in a wide pressure range is realized, and the anti-interference capability of the flexible pressure sensor is improved.
FIG. 1 is a schematic diagram of a flexible pressure sensor according to an embodiment of the present invention.
Referring to fig. 1, a flexible pressure sensor according to an embodiment of the present invention is a capacitive flexible pressure sensor, which includes: flexible electrode 110, composite dielectric film 120, high dielectric constant adhesive layer 130, foam porous electrode 140.
In particular, the flexible electrode 110 may include a flexible substrate and a conductive layer attached to a surface of the flexible substrate. Here, the material of the flexible substrate is one or more of the following materials: polymethoxysiloxane (PDMS), thermoplastic polyurethane elastomer (TPU), Polyacrylonitrile (PAN), polyethylene terephthalate (PET), Polyimide (PI), polylactic acid (PLA), and Polyethersulfone (PES).
A composite dielectric film 120 is disposed on the flexible electrode 110. The composite dielectric thin film 120 is formed of a polymer host material and a reinforcing phase material, wherein the reinforcing phase material is filled in a mass fraction of 1% to 10%. In one example, the composite dielectric film 120 is between 10-200 μm thick.
Here, the polymer host material is one or more of the following materials: polymethoxysiloxane (PDMS), thermoplastic polyurethane elastomer (TPU), Polyacrylonitrile (PAN), Polyamide (PA), polyvinylidene fluoride and its copolymers (PVDF & PVDF-HFP), polyvinyl alcohol (PVA), polylactic acid (PLA) and Polyethersulfone (PES). And the reinforcing phase material is one or more of the following nano-functional materials: dielectric ceramic nanopowder, hexagonal boron nitride, graphene, microphone (MXene), carbon nanotubes, black scales, graphite alkyne and polyaniline.
The high-k adhesive layer 130 is coated on the composite dielectric film 120. Here, the dielectric constant of the high dielectric constant adhesive layer is greater than 100. The high dielectric constant adhesive layer 130 is formed from an adhesive layer composite host material and an adhesive filler. Wherein, the adhesive layer compound main body material is one or more of the following materials: silica gel, Polyurethane (PU), epoxy resin, isocyanate and polyacrylic acid. And the adhesive filler is one or more of the following nano functional materials: dielectric ceramic nano powder, hexagonal boron nitride, polyaniline, aluminum oxide and silicon dioxide micro powder.
The foam porous electrode 140 overlies the high dielectric constant adhesive layer 130. In this embodiment, the material of the foam porous electrode 140 is aerogel conductive material, or a conductive material with a polymer foam skeleton as a main body and a surface conductive material attached to the conductive material with the polymer foam skeleton as a main body; wherein, when the material of the foam porous electrode 140 is an aerogel conductive material, the porosity of the aerogel conductive material is 0.1% to 2%; when the material of the foam porous electrode 140 is a conductive material with a polymer foam skeleton as a main body and a surface conductive material attached to the conductive material with the polymer foam skeleton as a main body, the porosity of the foam porous electrode 140 is 2% to 20% of the conductive material with the polymer foam skeleton as a main body.
In addition, the aerogel conductive material can be selected from one or more of graphene, carbon nanotubes, silver nanowires, gold nanowires and copper nanowires; the conductive material with the macromolecular foam framework as the main body is selected from polyurethane, polymethoxysiloxane, melamine, polyvinyl alcohol, natural rubber foam and nano-cellulose, and the surface conductive material is one or more of graphene, carbon nano-tubes, metal coatings and conductive polymers.
FIG. 2 is a flow chart of a method of making a flexible pressure sensor according to an embodiment of the present invention.
Referring to fig. 1 and 2 together, in step S210, the formed composite dielectric thin film 120 is fixed to the flexible electrode 110.
In one example, a method of forming the composite dielectric film 120 includes: selecting proper nano functional materials to carry out surface modification and purification in sequence to obtain an enhanced phase material; the reinforcing phase material and the selected polymer host material are prepared into a solution, and the composite dielectric thin film 120 is obtained by a solution casting method.
In one example, the method for surface modification of the nano-functional material comprises in-situ polymerization, diazotization, surface molecular grafting and addition of a stabilizer; the method for purifying the surface-modified nano functional material comprises the step of separating and purifying the surface-modified nano functional material in a centrifugation and low-temperature freeze-drying manner to obtain the enhanced phase material.
In one example, the method for preparing the reinforcing phase material and the selected polymer host material into a solution, and obtaining the composite dielectric film by means of solution casting comprises the following steps: adding a solvent into the enhanced phase material to prepare a dispersion liquid, and carrying out ultrasonic treatment on the dispersion liquid; adding the selected polymer main material into the dispersion liquid after ultrasonic treatment, stirring and dissolving, adding the film-forming aid, and coating the dispersion liquid added with the film-forming aid by an automatic film coating machine; and sequentially carrying out heating treatment and drying treatment on the coated dispersion liquid to obtain the composite dielectric film.
In step S220, the formed high-k adhesive layer 130 is coated on the composite dielectric film 120.
In step S230, the foamed porous electrode 140 formed by the manufacturing process is covered on the high dielectric constant adhesive layer 130.
In one example, a method of making the foam porous electrode 140 includes: the foam porous electrode formed into the aerogel conductive material is manufactured by adopting a colloid solution freeze-drying method, or the selected conductive material with the macromolecular foam framework as a main body is subjected to roughening or hydrophilic surface treatment, and the foam porous electrode is manufactured and formed by adopting an electroless deposition or solution impregnation method.
The method of making the flexible pressure sensor according to the embodiments of the present invention described above will be further described below in specific embodiments.
The method comprises the following steps: the composite dielectric film 120 is transferred onto the surface of the flexible electrode 110, and the composite dielectric film 120 is fixed onto the surface of the flexible electrode 110 by ultrasonic welding.
Specifically, the method of fabricating the flexible electrode 110 includes: the conductive layer material is prepared on the selected flexible substrate by means of magnetron sputtering, screen printing, inkjet printing and the like to form the flexible electrode 110.
Here, the method of manufacturing the composite dielectric thin film 120 is specifically as follows:
first, MXene material was prepared by adding 4.5g of lithium fluoride to a 100mL polytetrafluoroethylene hydrothermal kettle liner, then adding 60mL of hydrochloric acid, and stirring for 10 min. 3g of Ti are weighed3AlTi2And (3) ceramic powder, slowly pouring the powder into the etching solution, and then placing the inner container of the hydrothermal kettle into a hydrothermal pot at 40 ℃ for etching for 24 hours to obtain black suspension.
And secondly, separating and purifying the MXene material, putting the suspension into a centrifugal tube, centrifuging at the speed of 6000 rpm, taking the lower-layer precipitate, re-dispersing the lower-layer precipitate with deionized water, continuing centrifuging, and repeating the steps for multiple times until the pH value of the supernatant is more than 6. Diluting the centrifuged dispersion liquid to 2mg/mL, and then carrying out ultrasonic treatment on the diluted dispersion liquid for 30 minutes at a power of 200W under the protection of inert gas to obtain MXene dispersion liquid with high conductivity and specific surface area.
Next, surface modification of MXene material was performed by adding 0.75g of p-aminoacetanilide to 200mL of hydrochloric acid solution (1M) in an ice-water bath, slowly adding 50mL of sodium nitrite solution (1M) after it was dissolved by stirring, and further stirring for 1 hour to obtain a diazonium salt solution. 100mL of the freshly prepared diazonium salt solution is added into 1000mL of MXene dispersion liquid (2mg/mL), and the dispersion liquid reacts for 12 hours in an ice water bath under stirring to obtain the MXene dispersion liquid modified by azobenzene. The dispersion was centrifuged and freeze dried, and the surface modified MXene was redispersed with DMF to a 10mg/mL dispersion.
Finally, preparing the MXene/TPU composite dielectric film (namely the composite dielectric film 120), namely adding 10g of TPU particles into 100mL of DMF, stirring and dissolving, and then adding a certain amount of modified MXene dispersion liquid. Stirring the mixed solution for 15 minutes, dropwise adding the mixed solution with a certain volume onto a glass sheet (also can be a silicon wafer or mirror-polished stainless steel), placing the glass sheet on a heating table at 60 ℃ to volatilize most of the solvent, and finally placing the glass sheet into a vacuum oven at 80 ℃ to completely remove the residual solvent to obtain the composite dielectric film 120.
Step two: the fabricated high dielectric constant adhesive layer 130 is coated on the composite dielectric film 120. Specifically, compound adhesives a and B were mixed at a ratio of 10: 1, placing the mixture into an injection pump after uniformly mixing and shaking, starting the injection pump and an ultrasonic atomizer, and spraying the high-dielectric-constant adhesive layer on the surface of the composite dielectric film 120 by adopting a program-controlled XY-axis displacement platform.
Here, the method for manufacturing the high-k adhesive layer 130 specifically includes: taking 10g of nano barium titanate powder, adding the nano barium titanate powder into 100mL of hydrogen peroxide solution, heating the solution for several hours, then carrying out centrifugal separation, and dispersing the obtained precipitate in absolute ethyl alcohol after vacuum drying. Then, a KH550 solution with a mass fraction of 1% was added to the dispersion to perform surface silanization, and the barium titanate obtained by the treatment was dispersed in n-hexane by centrifugal washing. Adding a certain amount of hydroxyl-terminated silicone grease into barium titanate dispersion liquid to obtain a composite adhesive A, and taking 10% by mass of dibutyltin dilaurate tetraethyl orthosilicate solution as a composite adhesive B (curing effect).
Step three: and covering the foam porous electrode 140 on the high-dielectric-constant adhesive layer 130 at the pressure of 10kPa, and curing at normal temperature for 12h to complete bonding of the foam porous electrode 140 to obtain the capacitance type flexible pressure sensor with stable structure.
Here, the method of manufacturing the foam porous electrode 140 is specifically: cutting melamine foam into slices with the thickness of 1mm by adopting a die cutting machine, placing the slices in a dopamine hydrochloride solution with the concentration of 2g/L, adding a certain amount of sodium borate buffer solution to stabilize the pH value to about 8.5, stirring for 24 hours, taking out the slices, washing the foam slices for multiple times by adopting deionized water, and drying. And then placing the slices into a silver nanowire solution with the concentration of 0.1mg/mL, soaking for 15 minutes, taking out the foam slices, placing the foam slices into an oven for drying, and repeating the step for 3 times to obtain the foam porous electrode 140 with good conductivity.
Fig. 3 shows a graph comparing the performance of a flexible pressure sensor using pure TPU and MXene/TPU composite material as the dielectric layer. Referring to fig. 3, it can be seen that the sensitivity of the flexible pressure sensor with a pure TPU dielectric based is only 0.039kPa-1And flexible pressure transmission based on MXene/TPU composite material as dielectric layerThe sensitivity of the sensor is up to 0.77kPa-1The sensitivity is obviously improved, and the performance of the flexible pressure sensor based on the MXene/TPU composite material as the dielectric layer is superior to that of the existing capacitive pressure sensor based on the foam dielectric in a wide pressure range of 0-100 kPa.
The flexible pressure sensor has more applications in the detection of micro pressure of a human body, and particularly, the detection of pulse wave signals of the human body can be used for measuring heart rate and assisting in diagnosing cardiovascular diseases, and fig. 4 is a pulse wave signal diagram obtained by measuring the pulse pressure of the human body by using the flexible pressure sensor according to the embodiment of the invention. The waveform of the pulse wave with time can be clearly seen from fig. 4, which proves that the flexible pressure sensor according to the embodiment of the invention has better practical effect.
In summary, according to the flexible pressure sensor and the manufacturing method thereof of the embodiment of the invention, the composite film with a high dielectric constant is used as the dielectric layer, so that the capacitance variation of the flexible pressure sensor can be significantly increased, and the sensitivity of the flexible pressure sensor can be improved; meanwhile, the influence of parasitic capacitance and electromagnetic interference on the working stability of the flexible pressure sensor is reduced due to the increase of the capacitance, and the design cost of an ADC circuit and the like is reduced. In addition, according to the embodiment of the invention, the three-dimensional porous foam electrode is also adopted as the counter electrode of the capacitance sensor, so that the change of the polar plate distance of the sensor can be acted on the porous electrode, the bifurcation structure of the porous electrode contacting with the dielectric medium is easy to deform under low pressure, the low-pressure sensitivity is obviously improved, the polar plate distance of the capacitance formed by the porous electrode is continuously reduced under medium and high pressure, the sensor still has larger capacitance change amount due to the ultrahigh dielectric constant of the dielectric layer, and the detection of a wide pressure range can be realized.
The terms "exemplary," "example," and the like, as used throughout this specification, mean "serving as an example, instance, or illustration," and do not mean "preferred" or "advantageous" over other embodiments. The detailed description includes specific details for the purpose of providing an understanding of the described technology. However, the techniques may be practiced without these specific details. In some instances, well-known structures and devices are shown in block diagram form in order to avoid obscuring the concepts of the described embodiments.
Alternative embodiments of the present invention are described in detail with reference to the drawings, however, the embodiments of the present invention are not limited to the specific details in the above embodiments, and within the technical idea of the embodiments of the present invention, many simple modifications may be made to the technical solution of the embodiments of the present invention, and these simple modifications all belong to the protection scope of the embodiments of the present invention.
The previous description of the disclosure is provided to enable any person skilled in the art to make or use the disclosure. Various modifications to the disclosure will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other variations without departing from the scope of the disclosure. Thus, the description is not intended to be limited to the examples and designs described herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.
Claims (10)
1. A flexible pressure sensor, comprising:
a flexible electrode;
a composite dielectric film disposed on the flexible electrode;
the high-dielectric-constant adhesive layer is coated on the composite dielectric film;
and the foam porous electrode is covered on the high dielectric constant adhesive layer.
2. The flexible pressure sensor of claim 1, wherein the composite dielectric film is formed from a polymeric host material and a reinforcing phase material, wherein the reinforcing phase material has a packing mass fraction of 1% to 10%.
3. The flexible pressure sensor of claim 1, wherein the material of the foam porous electrode is an aerogel conductive material having a porosity of 0.1% to 2%;
or the foam porous electrode is made of a conductive material with a polymer foam framework as a main body, and the porosity of the conductive material with the polymer foam framework as the main body is 2-20%.
4. The flexible pressure sensor of claim 1 wherein the high dielectric constant adhesive layer has a dielectric constant greater than 100.
5. A method of making a flexible pressure sensor, the method comprising:
fixing the prepared and formed composite dielectric film on a flexible electrode;
coating the prepared and formed high-dielectric-constant adhesive layer on the composite dielectric film;
and covering the manufactured and formed foam porous electrode on the high dielectric constant adhesive layer.
6. The method of claim 5, wherein forming the composite dielectric film comprises: selecting proper nano functional materials to carry out surface modification and purification in sequence to obtain an enhanced phase material; and preparing the reinforced phase material and the selected polymer main body material into a solution, and obtaining the composite dielectric film in a solution film casting mode.
7. The manufacturing method of claim 5, wherein the method for surface modification of the nano-functional material comprises in-situ polymerization, diazotization, surface molecular grafting and stabilizer addition;
the method for purifying the surface-modified nano functional material comprises the step of separating and purifying the surface-modified nano functional material in a centrifugation and low-temperature freeze-drying manner to obtain the enhanced phase material.
8. The method of claim 6 or 7, wherein the step of preparing the reinforcing phase material and the selected polymer host material into a solution, and the step of obtaining the composite dielectric thin film by solution casting comprises:
adding a solvent into the enhanced phase material to prepare a dispersion liquid, and carrying out ultrasonic treatment on the dispersion liquid;
adding the selected polymer main material into the dispersion liquid after ultrasonic treatment, stirring and dissolving, adding the film-forming aid, and coating the dispersion liquid added with the film-forming aid by an automatic film coating machine;
and sequentially carrying out heating treatment and drying treatment on the coated dispersion liquid to obtain the composite dielectric film.
9. The method of manufacturing according to claim 5, wherein the method of manufacturing the foam porous electrode includes: the foam porous electrode formed into the aerogel conductive material is manufactured by adopting a colloid solution freeze-drying method, or the selected conductive material with the macromolecular foam framework as a main body is subjected to roughening or hydrophilic surface treatment, and the foam porous electrode is manufactured and formed by adopting an electroless deposition or solution impregnation method.
10. The method of claim 5, wherein the high-k adhesive layer has a dielectric constant greater than 100.
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