Flexible Archimedean spiral friction nanogenerator and its application in smart insoles

Abstract

The present invention discloses a flexible Archimedean spiral friction nanogenerator and its application in smart insoles, belonging to the field of smart wearables. The present invention can effectively improve the performance of the friction nanogenerator by setting the friction positive layer and the friction negative layer of the friction nanogenerator into mutually interlocking Archimedean spiral linear protrusion structures; the present invention only needs to make Archimedean spiral adjustments on the structure on the basis of the existing planar flexible friction nanogenerator to achieve performance improvement; the preparation method is simple and low in cost, suitable for actual process production and application; at the same time, the Archimedean spiral flexible friction nanogenerator of the present invention has good mechanical flexibility and high output performance, is non-toxic and harmless, has good biocompatibility, is small in size, and has excellent performance, and is suitable for use in the field of smart wearable technology such as smart insoles.

Description

Technical Field

[0001] The invention relates to a flexible Archimedean spiral friction nanogenerator and application thereof in a smart insole, belonging to the field of smart wearables. Background Art

[0002] With the increasing aging of the population and the growing demand for health management, there is an urgent need for smart wearable health monitoring devices. Among them, human gait recognition can obtain a lot of human physiological information in real time by collecting and analyzing the phase, frequency, peak value and other information of the foot sensor signal during human movement, which can be used in clinical diagnosis, health recovery and sports behavior analysis. For example, it can be used for early diagnosis of diseases such as diabetes, heart disease, plantar fasciitis, hallux valgus, etc.; or by analyzing the number of steps, distance and exercise intensity of athletes, and then optimizing competitive performance, realizing human health data management and intelligent interconnection. The gait sensing system is inseparable from safe, efficient and comfortable energy devices. As a new type of micro / nano energy technology, friction nanogenerators (TENGs) can convert mechanical energy, wind energy, water energy, etc. in the environment into electrical energy, realizing energy collection and effective utilization. Compared with rigid structures, flexible TENGs have excellent mechanical strength, flexibility and easy integration characteristics, providing a feasible solution for realizing the energy supply of wearable vital sign monitoring networks and developing self-powered sensors.

[0003] The output signal intensity limits many practical applications of TENGs. At present, there are some methods to improve the output signal, such as by changing the composition and preparation method of the friction layer, but there are still the following problems: (1) The electrical output performance test method is often affected by the experimental conditions and experimental equipment. The final performance of the publicly reported flexible TENGs varies greatly and cannot be directly compared; (2) The preparation process is complex and the production efficiency is low, which greatly limits its application in industrial production; (3) The friction nanogenerator is large in size and has poor mechanical flexibility, which is not suitable for use in the field of smart wearable health monitoring equipment, especially for smart insoles.

[0004] Therefore, it is of great significance to develop a friction nanogenerator that has both mechanical flexibility and electrical properties, high electrical signal output, long service life, and simple preparation process for use in a self-powered intelligent insole system. Summary of the invention

[0005] The technical problem to be solved by the present invention is to overcome at least one of the shortcomings of the above-mentioned prior art, and provide a flexible Archimedean spiral friction nanogenerator, wherein the friction positive layer and the friction negative layer of the friction nanogenerator are both provided with Archimedean spiral linear protrusion structures, and when in full contact, the Archimedean spiral linear protrusion structures of the two can be completely embedded with the concave structures on the opposite side. The friction nanogenerator using the Archimedean spiral structure can significantly improve its electrical output performance compared with the planar friction nanogenerator. Optionally, nanocellulose and polydimethylsiloxane are used as the friction electric substrate, and the friction polarity of polydimethylsiloxane is adjusted by adding electronegative poly (3,4-ethylenedioxythiophene) - poly (styrene sulfonic acid), increasing its surface charge as the friction negative layer during the contact-separation process, and improving its conductivity; barium titanate and multi-walled carbon nanotubes are introduced into nanocellulose to increase its dielectric constant as the friction positive layer material and improve its conductivity. The friction nanogenerator prepared by arranging the first electrode layer, the friction positive layer, the friction negative layer and the second electrode layer in sequence has good mechanical flexibility and high output voltage. Under complex mechanical deformation conditions, its output performance can still be maintained at a high level, and after 8000 cycles of continuous contact-separation process, it maintains a basically consistent open circuit voltage output, and has excellent cycle stability. Furthermore, in order to further broaden the practical application prospects of the flexible Archimedean spiral friction nanogenerator, the present invention also develops, designs and manufactures an intelligent insole system of the Archimedean spiral friction electric sensing array. By analyzing four foot movement postures and comparing them with the output signals of commercial piezoresistive insoles, the advantages of the present invention for the flexible intelligent insole system are compared and verified in detail.

[0006] In order to achieve the above object, the present invention is implemented through the following technical solutions:

[0007] The first purpose of the present invention is to provide a flexible Archimedean spiral friction nanogenerator, wherein the friction positive layer and the friction negative layer of the friction nanogenerator both have Archimedean spiral linear protrusion structures; the friction positive layer and the friction negative layer are arranged face to face, and in the initial state, the friction positive layer and the friction negative layer are in a separated state; when the friction positive layer and the friction negative layer are in full contact, the Archimedean spiral linear protrusion structures of the two can be completely embedded with the opposite side concave structure.

[0008] In one embodiment, the working mode of the friction nanogenerator is a contact-separation mode. Under the action of external force, the friction positive layer and the friction negative layer are in contact-separation process, and charges are generated on the surfaces of the friction positive layer and the friction negative layer. The charges are exported to the external circuit through the first electrode layer and the second electrode layer or generate electrical signals between other conductors. The first electrode layer attached to the friction positive layer and the second electrode layer attached to the friction negative layer are output electrodes for voltage and current.

[0009] In one embodiment, the thickness of the Archimedean spiral protrusion is d=1 mm, and the overall thickness of the tribopositive layer and the tribonegative layer is 1-1.5 mm.

[0010] In one embodiment, the diameter of the Archimedean spiral is 20-40 mm.

[0011] In one embodiment, the triboelectric positive layer (or triboelectric negative layer) is first prepared with a triboelectric positive layer (or triboelectric negative layer) material to form a planar structure with a certain thickness n, and then, based on the planar structure, a linear Archimedean spiral structure (such as Figure 7 The lower structure in the left figure); the triboelectric negative layer (or triboelectric positive layer) is a plane structure with a certain thickness n prepared by the friction material, and then cut within the range of thickness d on the basis of the plane structure to obtain a structure that can be completely embedded with the protruding structure of the triboelectric positive layer (similar to Figure 7 The upper structure in the left picture, Figure 7 The bottom of the nd thickness is omitted in the superstructure in the left figure).

[0012] In one embodiment, the flexible Archimedean spiral friction nanogenerator also includes a first electrode layer bonded to the friction positive layer and a second electrode layer bonded to the friction negative layer; the first electrode layer is fixed on the top flexible substrate, and the second electrode layer is fixed on the bottom flexible substrate.

[0013] In one embodiment, the first electrode layer and the second electrode layer are flexible electrode layers, optionally, conductive fabrics.

[0014] In one embodiment, the specific structure of the flexible Archimedean spiral friction nanogenerator is: a top flexible substrate, a first conductive fabric, a friction positive layer, a friction negative layer, a second conductive fabric, and a bottom flexible substrate; wherein the friction positive layer and the friction negative layer can be in contact and separated. Optionally, the top flexible substrate and the bottom flexible substrate are connected as a whole to form a flexible support skeleton (such as similar to CN116505791A Figure 1 structure), under the action of external force, the friction positive layer and the friction negative layer can be brought into contact and separation.

[0015] In one embodiment, the flexible support skeleton is an organic glass substrate.

[0016] In one embodiment, the friction layer material is a multi-dispersion system of nanocellulose-stabilized conductive nanoparticles or a multi-dispersion system of polymer elastomer-stabilized conductive nanoparticles, a stimulus-responsive conductive filler, such as carbon black (C), carbon nanotubes (CNT), graphene (GO), poly (3,4-ethylenedioxythiophene) / polystyrene sulfonate (PEDOT:PSS), two-dimensional transition metal carbon (nitride) (MXene), etc.

[0017] In one embodiment, the friction layer material is a binary dispersion system formed by a polymer elastomer or nanocellulose stabilized conductive nanoparticles, and functional nanofillers such as piezoelectric materials (barium titanate (BaTiO3), lead zirconate titanate (PbZrTiO3), lead magnesium niobate (PbNbMgO3)) or magnetic nanoparticles can be further introduced to construct a ternary stable system.

[0018] In one embodiment, the friction layer can be made into an Archimedean spiral structure through a polypropylene template casting, peeling and laser cutting process.

[0019] In one embodiment, the triboelectric positive layer is a CNT / BTO@BC membrane structure friction layer obtained by mixing bacterial cellulose (BC) with carbon nanotubes (CNT) and barium titanate (BTO) and subjecting the mixture to vacuum filtration and evaporation sintering; the triboelectric negative layer is a binary PEDOT:PSS@PDMS elastic dispersion system prepared by adding polydimethylsiloxane (PDMS) to poly 3,4-ethylenedioxythiophene / polystyrene sulfonate solution and subjecting the mixture to vacuum degassing, and then the elastic dispersion system is cast into a template and cured to obtain a PEDOT:PSS@PDMS elastic friction layer.

[0020] In the present invention, CNT is carbon nanotube, BTO is barium titanate, BC is bacterial cellulose, PEDOT:PSS is poly (3,4-ethylenedioxythiophene) / polystyrene sulfonate, and PDMS is polydimethylsiloxane.

[0021] In one embodiment, the CNT / BTO@BC membrane structure friction layer is prepared by dispersing CNT and BaTiO3 in a bacterial cellulose suspension, and mechanically stirring to obtain a CNT / BTO@BC homogeneous system; then, the CNT / BTO@BC homogeneous system is subjected to vacuum filtration and evaporation sintering technology at room temperature to obtain a CNT / BTO@BC membrane structure friction layer;

[0022] In one embodiment, the preparation of the PEDOT:PSS@PDMS elastic friction layer is as follows: a PEDOT:PSS solution (1-1.3 wt%) is added to dimethyl sulfoxide (DMSO) and stirred to obtain a PEDOT:PSS solution; then, a PDMS main agent is taken, a PDMS auxiliary agent and a PEDOT:PSS solution are slowly added thereto, magnetic stirring is performed at room temperature for 30 minutes, and a binary PEDOT:PSS@PDMS elastic dispersion system is obtained by vacuum degassing; the PEDOT:PSS@PDMS elastic dispersion system is cast on a polyethylene terephthalate (PET) flat template, and high-temperature curing is performed at 75°C for 2 hours to obtain a PEDOT:PSS@PDMS elastic friction layer;

[0023] The second object of the present invention is to provide a method for preparing a flexible triboelectric nanogenerator, comprising the following steps:

[0024] (1) Preparation of CNT / BTO@BC nanocellulose friction layer

[0025] The CNT / BTO@BC dispersion system was prepared by homogenous dispersion method. Specifically, 0.5g MWCNT and 1g BaTiO3 were dispersed in the bacterial cellulose suspension and stirred at 800rpm for 30min to obtain a CNT / BTO@BC homogenous system. Subsequently, the CNT / BTO@BC homogenous system was vacuum filtered and evaporation sintered at room temperature to obtain a CNT / BTO@BC film structure friction layer.

[0026] (2) Preparation of PEDOT:PSS@PDMS elastic friction layer

[0027] The PEDOT:PSS@PDMS dispersion system was prepared by homogeneous dispersion method. Specifically, 1.4mL PEDOT:PSS solution (1-1.3wt%) was added to 10mL dimethyl sulfoxide (DMSO) and stirred at 600rpm for 1h. Subsequently, 10g PDMS main agent was taken, 1g PDMS auxiliary agent and the above PEDOT:PSS solution were slowly added thereto, magnetically stirred at room temperature for 30min, and a binary PEDOT:PSS@PDMS elastic dispersion system was obtained by vacuum degassing. 10mL of the aforementioned PEDOT:PSS@PDMS elastic dispersion system was cast on a polyethylene terephthalate (PET) flat template and cured at 75°C for 2h to obtain a conductive polymer / elastomer self-supporting PEDOT:PSS@PDMS elastic friction layer with precisely controlled thickness;

[0028] (3) Preparation of flexible triboelectric nanogenerator

[0029] A flexible friction nanogenerator system was designed and manufactured based on the above-mentioned CNT / BTO@BC nanocellulose friction layer and PEDOT:PSS@PDMS elastic friction layer. Specifically, the prepared CNT / BTO@BC nanocellulose friction layer and PEDOT:PSS@PDMS elastic friction layer were respectively covered on the top and bottom surfaces of the organic glass substrate, and the conductive fabric was adhered between the friction layer and the organic glass interface.

[0030] In one embodiment, in step (1), the nanocellulose may be cellulose nanofibers (CNF), cellulose nanocrystals (CNC) and bacterial cellulose (BC).

[0031] In one embodiment, in step (1), the mass ratio of nanocellulose, carbon nanotubes and barium titanate is (50-100): (5-20): (2-10).

[0032] In one embodiment, the nanocellulose friction layer and the elastic friction layer in step (1) and step (2) can be formed by laser etching a flexible self-supporting pressure-electric response membrane, and an Archimedean spiral structure can be selected.

[0033] Preferably, the laser etching process of the self-supporting pressure-electric response material of the Archimedean spiral structure is: diameter 20-40 mm, thickness 200-1200 μm.

[0034] In one embodiment, the working mode of the friction nanogenerator is a vertical contact-separation mode. Under the action of external force, the nanocellulose-based positive friction layer and the elastic negative friction layer are in contact-separation process, and charges are generated on the surfaces of the nanocellulose-based positive friction layer and the elastic negative friction layer. The charges are exported to the external circuit through the flexible conductive layer or generate electrical signals between other conductors. The upper flexible electrode layer and the lower flexible electrode layer are output electrodes for voltage and current.

[0035] The third purpose of the present invention is to provide a method for improving the performance of a friction nanogenerator, wherein the friction nanogenerator includes a friction positive layer and a friction negative layer; the method is characterized in that the friction positive layer and the friction negative layer are arranged to both have Archimedean spiral-shaped protrusion structures; the friction positive layer and the friction negative layer are arranged face to face, and in the initial state, the friction positive layer and the friction negative layer are in a separated state; when the friction positive layer and the friction negative layer are in full contact, the Archimedean spiral-shaped protrusion structures of the two layers can be completely embedded with the corresponding concave structures.

[0036] The fourth object of the present invention is to provide a flexible Archimedean spiral friction nanogenerator for use in energy conversion and wearable self-powered sensing devices.

[0037] In one embodiment, the application is in the field of smart insoles.

[0038] In one embodiment, the smart insole includes a plurality of the flexible Archimedean spiral friction nanogenerators, which can be arranged in an array on the insole corresponding to the toes, midfoot, heel, etc.; the human body movement type or movement characteristics can be analyzed by analyzing the differences in characteristic signals such as phase, time, peak value or frequency of the output electrical signals of each flexible Archimedean spiral friction nanogenerator.

[0039] The present invention also provides a device for analyzing human motion types or motion characteristics, using the flexible Archimedean spiral friction nanogenerator of the present invention; optionally, a smart insole containing the flexible Archimedean spiral friction nanogenerator of the present invention is used to analyze the human motion type or motion characteristics by analyzing the differences in characteristic signals such as phase, time, peak value or frequency of the output electrical signals of each flexible Archimedean spiral friction nanogenerator.

[0040] Advantages and effects of the present invention:

[0041] 1. The Archimedean spiral flexible friction nanogenerator of the present invention can effectively improve the performance of the friction nanogenerator by setting the friction positive layer and the friction negative layer of the friction nanogenerator into mutually interlocking Archimedean spiral linear protrusion structures; compared with the flexible friction nanogenerator of the same friction material on the plane, the open circuit voltage of the Archimedean spiral flexible friction nanogenerator of the present invention can be increased by 40-123%, the short circuit current can be increased by 17%-153%, and the power density can be increased by 215%-462%. In addition, the Archimedean spiral flexible friction nanogenerator of the present invention can generate electric charge through contact-separation regardless of the relative angle between the friction positive layer and the friction negative layer.

[0042] 2. The Archimedean spiral flexible friction nanogenerator of the present invention is found to have a better improvement ratio when using an Archimedean spiral structure with a diameter of about 40 mm; in addition, the Archimedean spiral flexible friction nanogenerator of the present invention has a small size, good mechanical flexibility, and excellent output electrical performance, and is suitable for use in smart wearable technology fields such as smart insoles.

[0043] 3. The flexible Archimedean spiral friction nanogenerator of the present invention can achieve performance improvement by only making Archimedean spiral adjustments in structure based on the existing planar flexible friction nanogenerator; the preparation method is simple and low-cost, and does not require major adjustments to the existing planar flexible friction nanogenerator, and is suitable for actual production applications.

[0044] 4. The flexible friction nanogenerator prepared by the present invention has good mechanical flexibility and high output performance. Its output performance can be maintained at a high level during the continuous contact-separation process. After working for 8000 cycles, the voltage remains good, the open circuit voltage remains basically unchanged, and it has good cycle stability.

[0045] 5. The present invention adopts evaporation sintering / vacuum filtration and laser etching strategies to prepare Archimedean spiral friction positive and negative layers with uniform structure and good morphology, and then construct Archimedean spiral flexible friction nanogenerators, which have simple operation and low cost in production process; further, the present invention improves the materials of the friction positive and negative layers, and the obtained Archimedean spiral flexible friction nanogenerator has high mechanical flexibility (fracture strength of about 480Mpa), low cost, non-toxic and harmless, and good biocompatibility. In addition, the nanocellulose-based friction electric layer with Archimedean spiral structure has high flexibility of movement.

[0046] 6. Based on the Archimedean spiral flexible friction nanogenerator involved in the present invention, a light, comfortable and wearable intelligent insole system for foot posture detection can be designed and manufactured. Through structural design, a rich arrangement of signal collection points per unit area is achieved, which greatly improves the accuracy of motion detection, can efficiently identify the motion characteristics of people with different body shapes, has customizability and high flexibility, and provides new ideas and feasible solutions for the Archimedean spiral flexible friction nanogenerator to move from theory to actual production application in the field of mechanical energy collection and self-powered sensing. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Figure 1 This is a scanning electron microscope image (SEM) of the bacterial cellulose used in the present invention.

[0048] Figure 2 This is the scanning electron microscope (SEM) image of CNT / BTO@BC and PEDOT:PSS@PDMS in Example 3.

[0049] Figure 3 This is the conductivity characteristic diagram of CNT / BTO@BC and PEDOT:PSS@PDMS in Example 3.

[0050] Figure 4 A schematic diagram of a process for preparing the Archimedean spiral CNT / BTO@BC nanocellulose friction layer of the present invention.

[0051] Figure 5 A schematic diagram of a process for preparing the Archimedean spiral PEDOT:PSS@PDMS elastic friction layer of the present invention.

[0052] Figure 6Schematic diagram of the working principle of the Archimedean screw (D=20 and 40 mm) friction nanogenerator in Examples 5-6.

[0053] Figure 7 Schematic diagram of the Archimedean screw (D=20 and 40 mm) friction nanogenerator in Examples 5-6.

[0054] Figure 8 Graph showing the electrical output characteristics of the flexible Archimedean screw (D=20 and 40 mm) friction nanogenerators in Examples 5 and 6.

[0055] Fig. 9 This is a graph showing the electrical output characteristics of the flexible Archimedean spiral friction nanogenerator in Example 6 at an operating frequency of 3 Hz-6 Hz.

[0056] Fig.10 This is a graph showing the electrical output characteristics of the flexible Archimedean spiral friction nanogenerator in Example 6 at 50Pa-10 KPa.

[0057] Fig.11 This is a test diagram of the output power of the flexible Archimedean spiral friction nanogenerator in Example 6 when an external load is connected.

[0058] Fig.12 This is a COMSOL potential simulation diagram of the flexible Archimedean spiral friction nanogenerator in Example 6, which shows the simulated potential at different separation distances between the friction layers.

[0059] Fig.13 This is a test diagram of the cyclic stability of the flexible Archimedean spiral friction nanogenerator in Example 6.

[0060] Fig.14 Schematic diagram of the triboelectric array of the flexible Archimedean spiral friction nanogenerator used for self-powered smart insoles in Example 6.

[0061] Fig.15 This is a comparison chart of the output signals of the Archimedean spiral structure triboelectric smart insole in Example 6 and the commercial smart insole. DETAILED DESCRIPTION

[0062] The technical solution of the present invention is further described below in conjunction with the accompanying drawings and preferred embodiments.

[0063] 1. Preparation of nanocellulose used in friction layer (taking bacterial cellulose as an example)

[0064] The bacterial cellulose prepared by biosynthetic fermentation of Acetobacter xylinum (ATCC 10245) was treated with alkali and then repeatedly washed with deionized water to prepare pure BC hydrogel membrane. The membrane was observed by scanning electron microscopy (SEM). Figure 1As shown, the successful preparation of nanocellulose with uniform diameter (50±10 nm) was verified (Wang, Sha, et al. "Super-strong, super-stiff macrofibers with aligned, long bacterial cellulose nanofibers." Advanced Materials 2017, 29(35): 1702498). The BC prepared above was subjected to sol-gel treatment by continuous magnetic stirring at 40°C for 24 h using HCOOH / PBS / PF127 system.

[0065] 2. Working principle and structure diagram of flexible Archimedean spiral friction nanogenerator:

[0066] The working principle of the flexible Archimedean spiral friction nanogenerator is shown in the attached figure. Figure 6 As shown, the triboelectric positive layer (taking CNT / BTO@BC as an example) and the triboelectric negative layer (taking PEDOT:PSS@PDMS as an example) contact and separate under the action of external force to generate charge, and the electrode layer is used to transmit charge; optionally, PDMS can be used to provide elastic contact-separation interval and be used for the packaging of triboelectric nanogenerators; the first electrode layer and the second electrode layer are attached to the back of the triboelectric positive layer and the triboelectric negative layer, respectively, as output electrodes for voltage and current. In particular, the Archimedean spiral protrusion thickness of each triboelectric layer is 1mm ( Figure 6 The total thickness of the friction positive layer and the friction negative layer is 1.5 mm.

[0067] When the flexible Archimedean spiral friction nanogenerator moves in the horizontal direction ( Figure 7 ), the Archimedean spiral moves in a circle around a fixed center on a clockwise plane, two contact points are formed between the sliding spiral and the fixed spiral, and the external contact point moves inward, thereby ensuring that the pressure and charge transfer process occurs continuously. Among them, W is the spiral line width, S is the distance between two adjacent lines of the Archimedean spiral, and R is the radius of the Archimedean spiral.

[0068] Example 1: Preparation method of flexible friction nanogenerator

[0069] Preparation of CNT / BTO@BC nanocellulose friction layer: The CNT / BTO@BC dispersion system was prepared by homogenous dispersion method. Specifically, 0.5g MWCNT and 1g BaTiO3 were dispersed in the aforementioned bacterial cellulose suspension and stirred at 800rpm for 30min to obtain a CNT / BTO@BC homogeneous system. Subsequently, the CNT / BTO@BC homogeneous system was subjected to vacuum filtration and evaporation sintering technology at room temperature to obtain a CNT / BTO@BC membrane structure friction layer. The thickness of the CNT / BTO@BC membrane structure friction layer (1-1.5mm) was obtained by controlling the content of the CNT / BTO@BC homogeneous system.

[0070] Preparation of PEDOT:PSS@PDMS elastic friction layer: PEDOT:PSS@PDMS dispersion system was prepared by homogeneous dispersion method. Specifically, 1.4mL PEDOT:PSS solution (1-1.3wt%) was added to 10mL dimethyl sulfoxide (DMSO) and stirred at 600rpm for 1h. Subsequently, 10g PDMS main agent was taken, 1g PDMS auxiliary agent and the above PEDOT:PSS solution were slowly added thereto, magnetically stirred at room temperature for 30min, and a binary PEDOT:PSS@PDMS elastic dispersion system was obtained by vacuum degassing. 10mL of the above PEDOT:PSS@PDMS elastic dispersion system was cast on a polyethylene terephthalate (PET) flat template (thickness of 1-1.5mm), and cured at 75℃ for 2h to obtain a conductive polymer / elastomer self-supporting PEDOT:PSS@PDMS elastic friction layer with precisely controlled thickness.

[0071] A flexible friction nanogenerator system was designed and manufactured based on the above-mentioned CNT / BTO@BC nanocellulose friction layer and PEDOT:PSS@PDMS elastic friction layer. Specifically, the prepared CNT / BTO@BC nanocellulose friction layer and PEDOT:PSS@PDMS elastic friction layer were respectively covered on the top and bottom surfaces of the organic glass substrate, and the conductive fabric was adhered between the friction layer and the organic glass interface.

[0072] Under the action of external force, the CNT / BTO@BC nanocellulose friction layer and the PEDOT:PSS@PDMS elastic friction layer generate charges through contact-separation to achieve energy conversion and self-powered sensing. The Keithley 6514 electrometer was used to record the triboelectric output electrical signals under different pressures and operating frequencies, and the stability of the output electrical signals over time was analyzed. Conductive fabric was used to connect the conductive layer of the flexible friction nanogenerator, and the other end of the conductive fabric was simultaneously connected to external loads of different sizes. The current and voltage changes caused by the changes in the external load in the conductive path were calculated by the formula Calculate the maximum power output.

[0073] Example 2: Preparation method of flexible friction nanogenerator

[0074] Preparation of CNT / BTO@BC nanocellulose friction layer: The CNT / BTO@BC dispersion system was prepared by homogenous dispersion method. Specifically, 1g MWCNT and 1g BaTiO3 were dispersed in the aforementioned bacterial cellulose suspension and stirred at 800rpm for 30min to obtain a CNT / BTO@BC homogeneous system. Subsequently, the CNT / BTO@BC homogeneous system was subjected to vacuum filtration and evaporation sintering technology at room temperature to obtain a CNT / BTO@BC membrane structure friction layer. The thickness of the CNT / BTO@BC membrane structure friction layer (1-1.5mm) was obtained by controlling the content of the CNT / BTO@BC homogeneous system.

[0075] Preparation of PEDOT:PSS@PDMS elastic friction layer: PEDOT:PSS@PDMS dispersion system was prepared by homogeneous dispersion method. Specifically, 1.4mL PEDOT:PSS solution (1-1.3wt%) was added to 10mL dimethyl sulfoxide (DMSO) and stirred at 600rpm for 1h. Subsequently, 10g PDMS main agent was taken, 1g PDMS auxiliary agent and the above PEDOT:PSS solution were slowly added thereto, magnetically stirred at room temperature for 30min, and a binary PEDOT:PSS@PDMS elastic dispersion system was obtained by vacuum degassing. 10mL of the above PEDOT:PSS@PDMS elastic dispersion system was cast on a polyethylene terephthalate (PET) flat template (thickness of 1-1.5mm), and cured at 75℃ for 2h to obtain a conductive polymer / elastomer self-supporting PEDOT:PSS@PDMS elastic friction layer with precisely controlled thickness.

[0076] A flexible friction nanogenerator system was designed and manufactured based on the above-mentioned CNT / BTO@BC nanocellulose friction layer and PEDOT:PSS@PDMS elastic friction layer. Specifically, the prepared CNT / BTO@BC nanocellulose friction layer and PEDOT:PSS@PDMS elastic friction layer were respectively covered on the top and bottom surfaces of the organic glass substrate, and the conductive fabric was adhered between the friction layer and the organic glass interface.

[0077] Under the action of external force, the CNT / BTO@BC nanocellulose friction layer and the PEDOT:PSS@PDMS elastic friction layer generate charges through contact-separation to achieve energy conversion and self-powered sensing. The Keithley 6514 electrometer was used to record the triboelectric output electrical signals under different pressures and operating frequencies, and the stability of the output electrical signals over time was analyzed. Conductive fabric was used to connect the conductive layer of the flexible friction nanogenerator, and the other end of the conductive fabric was simultaneously connected to external loads of different sizes. The current and voltage changes caused by the changes in the external load in the conductive path were calculated by the formula Calculate the maximum power output.

[0078] Example 3: Preparation method of flexible friction nanogenerator

[0079] Preparation of CNT / BTO@BC nanocellulose friction layer: The CNT / BTO@BC dispersion system was prepared by homogenous dispersion method. Specifically, 2g MWCNT and 1g BaTiO3 were dispersed in the aforementioned bacterial cellulose suspension and stirred at 800rpm for 30min to obtain a CNT / BTO@BC homogeneous system. Subsequently, the CNT / BTO@BC homogeneous system was subjected to vacuum filtration and evaporation sintering technology at room temperature to obtain a CNT / BTO@BC membrane structure friction layer. The thickness of the CNT / BTO@BC membrane structure friction layer (1-1.5mm) was obtained by controlling the content of the CNT / BTO@BC homogeneous system.

[0080] Preparation of PEDOT:PSS@PDMS elastic friction layer: PEDOT:PSS@PDMS dispersion system was prepared by homogeneous dispersion method. Specifically, 1.4mL PEDOT:PSS solution (1-1.3wt%) was added to 10mL dimethyl sulfoxide (DMSO) and stirred at 600rpm for 1h. Subsequently, 10g PDMS main agent was taken, 1g PDMS auxiliary agent and the above PEDOT:PSS solution were slowly added thereto, magnetically stirred at room temperature for 30min, and a binary PEDOT:PSS@PDMS elastic dispersion system was obtained by vacuum degassing. 10mL of the above PEDOT:PSS@PDMS elastic dispersion system was cast on a polyethylene terephthalate (PET) flat template (thickness of 1-1.5mm), and cured at 75℃ for 2h to obtain a conductive polymer / elastomer self-supporting PEDOT:PSS@PDMS elastic friction layer with precisely controlled thickness.

[0081] like Figure 2 The scanning electron microscopy (SEM) images of CNT / BTO@BC and PEDOT:PSS@PDMS are shown in Figure 2. Figure 3 This is the conductivity characteristics diagram of CNT / BTO@BC and PEDOT:PSS@PDMS.

[0082] A flexible friction nanogenerator system was designed and manufactured based on the above-mentioned CNT / BTO@BC nanocellulose friction layer and PEDOT:PSS@PDMS elastic friction layer. Specifically, the prepared CNT / BTO@BC nanocellulose friction layer and PEDOT:PSS@PDMS elastic friction layer were respectively covered on the top and bottom surfaces of the organic glass substrate, and the conductive fabric was adhered between the friction layer and the organic glass interface.

[0083] Under the action of external force, the CNT / BTO@BC nanocellulose friction layer and the PEDOT:PSS@PDMS elastic friction layer generate charges through contact-separation to achieve energy conversion and self-powered sensing. The Keithley 6514 electrometer was used to record the triboelectric output electrical signals under different pressures and operating frequencies, and the stability of the output electrical signals over time was analyzed. Conductive fabric was used to connect the conductive layer of the flexible friction nanogenerator, and the other end of the conductive fabric was simultaneously connected to external loads of different sizes. The current and voltage changes caused by the changes in the external load in the conductive path were calculated by the formula Calculate the maximum power output.

[0084] Example 4: Preparation method of flexible friction nanogenerator

[0085] Preparation of CNT / BTO@BC nanocellulose friction layer: The CNT / BTO@BC dispersion system was prepared by homogenous dispersion method. Specifically, 2g MWCNT and 1g BaTiO3 were dispersed in the aforementioned bacterial cellulose suspension and stirred at 800rpm for 30min to obtain a CNT / BTO@BC homogeneous system. Subsequently, the CNT / BTO@BC homogeneous system was subjected to vacuum filtration and evaporation sintering technology at room temperature to obtain a CNT / BTO@BC membrane structure friction layer. The thickness of the CNT / BTO@BC membrane structure friction layer (1-1.5mm) was obtained by controlling the content of the CNT / BTO@BC homogeneous system.

[0086] Preparation of PDMS elastic friction layer: The PDMS dispersion system was prepared by homogeneous dispersion method. Specifically, 10g of PDMS main agent was taken, 1g of PDMS auxiliary agent was slowly added thereto, magnetic stirring was performed at room temperature for 30min, and a monovalent PDMS elastic dispersion system was obtained by vacuum degassing. 10mL of the above PDMS elastic dispersion system was cast on a polyethylene terephthalate (PET) flat template (thickness of 1-1.5mm), and high-temperature cured at 75°C for 2h to obtain a conductive polymer / elastomer self-supporting PDMS elastic friction layer with precisely controlled thickness.

[0087] A flexible friction nanogenerator system was designed and manufactured based on the above-mentioned CNT / BTO@BC nanocellulose friction layer and PDMS elastic friction layer. Specifically, the prepared CNT / BTO@BC nanocellulose friction layer and PDMS elastic friction layer were respectively covered on the top and bottom surfaces of the organic glass substrate, and the conductive fabric was adhered between the friction layer and the organic glass interface.

[0088] Under the action of external force, the CNT / BTO@BC nanocellulose friction layer and the PDMS elastic friction layer generate charges through contact-separation to achieve energy conversion and self-powered sensing. The Keithley 6514 electrometer was used to record the triboelectric output electrical signals under different pressures and operating frequencies, and the stability of the output electrical signals over time was analyzed. Conductive fabric was used to connect the conductive layer of the flexible friction nanogenerator, and the other end of the conductive fabric was simultaneously connected to external loads of different sizes. The current and voltage changes caused by the changes in the external load in the conductive path were calculated by the formula Calculate the maximum power output.

[0089] Example 5: Preparation method of flexible Archimedean spiral friction nanogenerator

[0090] Preparation of Archimedean spiral CNT / BTO@BC nanocellulose friction layer: The CNT / BTO@BC dispersion system was prepared by homogenous dispersion method. Specifically, 2g MWCNT and 1g BaTiO3 were dispersed in the bacterial cellulose suspension of (1) and stirred at 800rpm for 30min to obtain a CNT / BTO@BC homogeneous system. Subsequently, the CNT / BTO@BC homogeneous system was subjected to vacuum filtration and evaporation sintering technology at room temperature to obtain a CNT / BTO@BC nanocellulose friction layer. Finally, the Archimedean spiral (D=20mm) CNT / BTO@BC nanocellulose friction layer (i.e., the friction positive layer, with a thickness of 1-1.5mm) was obtained by polypropylene template casting, peeling and laser cutting process, as shown in FIG. Figure 4 As shown (wherein the thickness of the Archimedean spiral protrusion is 1 mm).

[0091] Preparation of Archimedean spiral PEDOT:PSS@PDMS elastic friction layer: The PEDOT:PSS@PDMS dispersion system was prepared by homogeneous dispersion method. Specifically, 1.4mL PEDOT:PSS solution (1-1.3wt%) was added to 10mL dimethyl sulfoxide (DMSO) and stirred at 600rpm for 1h. Subsequently, 10g PDMS main agent was taken, 1g PDMS auxiliary agent and the above PEDOT:PSS solution were slowly added thereto, and magnetic stirring was performed at room temperature for 30min. The binary PEDOT:PSS@PDMS elastic dispersion system was obtained by vacuum degassing. 10 mL of the aforementioned PEDOT:PSS@PDMS elastic dispersion system was cast on a polyethylene terephthalate (PET) Archimedean spiral structure template (diameter D=20 mm, thickness 1-1.5 mm), and cured at 75°C for 2 h to obtain a self-supporting Archimedean spiral (D=20 mm) PEDOT:PSS@PDMS elastic friction layer (i.e., a triboelectric negative layer) with a precisely controlled thickness. Figure 5 As shown (wherein the thickness of the Archimedean spiral protrusion is 1 mm).

[0092] A flexible friction nanogenerator system was designed and manufactured based on the above-mentioned Archimedean spiral CNT / BTO@BC nanocellulose friction layer and Archimedean spiral PEDOT:PSS@PDMS elastic friction layer. Specifically, the prepared Archimedean spiral CNT / BTO@BC nanocellulose friction layer and Archimedean spiral PEDOT:PSS@PDMS elastic friction layer were respectively covered on the top and bottom surfaces of the organic glass substrate (wherein the positive friction layer and the negative friction layer were arranged opposite to each other, and the Archimedean spiral protrusion corresponded to the depression on the opposite side), and the conductive fabric was adhered between the friction layer and the organic glass interface.

[0093] Under the action of external force, the Archimedean spiral CNT / BTO@BC nanocellulose friction layer and the Archimedean spiral PEDOT:PSS@PDMS elastic friction layer generate charges through contact-separation to achieve energy conversion and self-powered sensing. The Keithley 6514 electrometer was used to record the triboelectric output electrical signals under different pressures and operating frequencies, and the stability of the output electrical signals over time was analyzed. Conductive fabric was used to connect the conductive layer of the flexible friction nanogenerator, and the other end of the conductive fabric was simultaneously connected to external loads of different sizes. The current and voltage changes caused by the changes in the external load in the conductive path were calculated by the formula Calculate the maximum power output.

[0094] Example 6: Preparation method of flexible Archimedean spiral friction nanogenerator

[0095] The method of Example 5 was used to prepare the tribopositive layer and the tribonegative layer, except that the Archimedean screw D=40 mm. Specifically:

[0096] Preparation of Archimedean spiral CNT / BTO@BC nanocellulose friction layer: The CNT / BTO@BC dispersion system was prepared by homogenous dispersion method. Specifically, 2g MWCNT and 1g BaTiO3 were dispersed in the bacterial cellulose suspension of (1) and stirred at 800rpm for 30min to obtain a CNT / BTO@BC homogeneous system. Subsequently, the CNT / BTO@BC homogeneous system was subjected to vacuum filtration and solvent evaporation at room temperature to obtain a CNT / BTO@BC nanocellulose friction layer. Finally, an Archimedean spiral (D=40mm) CNT / BTO@BC nanocellulose friction layer (thickness of 1-1.5mm) was obtained by polypropylene template casting, peeling and laser cutting.

[0097] Preparation of Archimedean spiral PEDOT:PSS@PDMS elastic friction layer: The PEDOT:PSS@PDMS dispersion system was prepared by homogeneous dispersion method. Specifically, 1.4mL PEDOT:PSS solution (1-1.3wt%) was added to 10mL dimethyl sulfoxide (DMSO) and stirred at 600rpm for 1h. Subsequently, 10g PDMS main agent was taken, 1g PDMS auxiliary agent and the above PEDOT:PSS solution were slowly added thereto, and magnetic stirring was carried out at room temperature for 30min. The binary PEDOT:PSS1@PDMS elastic dispersion system was obtained by vacuum degassing. 10 mL of the aforementioned PEDOT:PSS@PDMS elastic dispersion system was cast on a polyethylene terephthalate (PET) Archimedean spiral template (diameter D=40 mm, thickness 1-1.5 mm), and cured at 75°C for 2 h to obtain a conductive polymer / elastomer self-supporting Archimedean spiral (D=40 mm) PEDOT:PSS@PDMS elastic friction layer with precisely controlled thickness.

[0098] Based on the above Archimedean spiral CNT / BTO@BC nanocellulose friction layer (triboelectric layer) and Archimedean spiral PEDOT:PSS@PDMS elastic friction layer (triboelectric layer), a flexible triboelectric nanogenerator system (D=40mm) was designed and manufactured. The triboelectric positive layer and the triboelectric negative layer are arranged face to face, and the Archimedean spiral protrusion corresponds to the depression on the opposite side; the triboelectric nanogenerator also includes a first electrode layer bonded to the triboelectric positive layer, a second electrode layer bonded to the triboelectric negative layer, and a flexible support frame; the first electrode layer and the second electrode layer are both fixed on the flexible support frame (for example, it can be the one in CN116505791A Figure 1 Structure)

[0099] In this embodiment, specifically, the prepared Archimedean spiral CNT / BTO@BC nanocellulose friction layer and Archimedean spiral PEDOT:PSS@PDMS elastic friction layer are respectively covered on the top and bottom organic glass substrate surfaces (flexible support skeletons), and the conductive fabric (electrode layer) is adhered between the friction layer and the organic glass interface.

[0100] Under the action of external force, the Archimedean spiral CNT / BTO@BC nanocellulose friction layer and the Archimedean spiral PEDOT:PSS@PDMS elastic friction layer generate charges through contact-separation to achieve energy conversion and self-powered sensing. The Keithley 6514 electrometer was used to record the triboelectric output electrical signals under different pressures and operating frequencies, and the stability of the output electrical signals over time was analyzed. Conductive fabric was used to connect the conductive layer of the flexible friction nanogenerator, and the other end of the conductive fabric was simultaneously connected to external loads of different sizes. The current and voltage changes caused by the changes in the external load in the conductive path were calculated by the formula Calculate the maximum power output.

[0101] The mechanical properties and electrical properties of the friction layers (CNT / BTO@BC-PEDOT:PSS@PDMS) prepared in Examples 1-4 were tested, and the results are shown in Table 1.

[0102] Table 1 Mechanical properties and electrical properties of the friction layer (CNT / BTO@BC-PEDOT:PSS@PDMS) prepared in Examples 1-4

[0103]

[0104] Under the conditions of an operating frequency of 8 Hz and an applied pressure of 10 KPa, the output performance of the flexible friction nanogenerators prepared in Examples 1-6 was tested. The results are shown in Tables 2 and Figure 8 shown.

[0105] Table 2 Output performance of flexible friction nanogenerator prepared in Example

[0106]

[0107] Example 7: Effect of friction layer size on electrical output performance of flexible friction nanogenerator

[0108] Referring to the method for preparing the flexible friction nanogenerator in Example 6, only the size of the Archimedean screw of the friction layer was changed, and the output performance of the prepared flexible friction nanogenerator was tested. The results are as follows: Figure 8As shown, the size increases from 20 mm in diameter to 40 mm, and the output voltage increases from 24.5 V to 40.1 V. As the size of the friction layer increases, the total amount of charge transferred between the two friction layers (CNT / BTO@BC and PEDOT:PSS@PDMS) increases, so the electrical output performance increases.

[0109] Example 8: Effects of different operating frequencies on the electrical output performance of flexible friction nanogenerators

[0110] Referring to the method for measuring the output performance of the flexible friction nanogenerator in Example 6, only the operating frequency was changed to test the output performance of the prepared flexible friction nanogenerator. The results are as follows: Fig. 9 As shown in the figure, when the device applies a constant pressure of 10KPa, the operating frequency of the device increases from 3Hz to 6Hz, and the output voltage of the flexible friction nanogenerator device (diameter D = 20mm) increases from 12.2V to 23.6V; the output voltage of the flexible friction nanogenerator device (diameter D = 40mm) increases from 15.0V to 29.8V. The increase in frequency leads to an increase in the amount of charge per unit time, which well explains the increase in output voltage.

[0111] Example 9: Effects of different pressures on the electrical output performance of flexible friction nanogenerators

[0112] By making flexible friction nanogenerator devices with diameter D=20 mm and diameter D=40 mm (i.e., the flexible friction nanogenerators prepared in Examples 5 and 6), the results are as follows: Fig.10 As shown in the figure, when the operating frequency is constant at 6Hz, the pressure applied by the device increases from 50Pa to 10KPa, and the corresponding output voltage of the flexible friction nanogenerator device (diameter D = 20mm) increases from 1.9V to 7.5V; the output voltage of the flexible friction nanogenerator device (diameter D = 40mm) increases from 4.5V to 29.8V. As the pressure increases, the contact area of ​​the two friction layers (CNT / BTO@BC and PEDOT:PSS@PDMS) also increases, resulting in an increase in voltage.

[0113] Example 10: Effects of different loads on the electrical output performance of flexible friction nanogenerators

[0114] The flexible Archimedean spiral friction nanogenerator prepared in Example 6 was connected to different loads to obtain the output power test graph, as shown in FIG. Fig.11 shown.

[0115] Example 11: Stability Test

[0116] The flexible Archimedean spiral friction nanogenerator prepared in Example 6 was selected to test its stability. Fig.13As shown in the figure, the flexible friction nanogenerator shows high stability in the cycle measurement. After the flexible friction nanogenerator runs for 8000 stable cycles in the indoor environment (25℃, 45% RH), the output voltage always remains at the initial value. This shows that the flexible friction nanogenerator has good electrical signal output stability.

[0117] Application example: Application of Archimedean spiral friction nanogenerator in smart insoles

[0118] A new type of triboelectric array intelligent insole system was designed and prepared, which consists of a flexible triboelectric nanogenerator (refer to the flexible triboelectric nanogenerator prepared in Example 6). Through a programmable triboelectric array design, an intelligent insole composed of flexible triboelectric nanogenerators of different numbers and sizes is integrated. The movement type or movement characteristics are obtained by analyzing the differences in phase, time, amplitude and frequency of multiple self-driven sensor output signals of the foot during movement, which is used for plantar health monitoring and sports posture management.

[0119] Flexible Archimedean spiral friction nanogenerator can be used for self-powered smart insoles. Fig.14 As shown in FIG. 1 , the fabricated Archimedean spiral friction nanogenerator system is arranged in an array on the surface of a polyethylene terephthalate (PET) substrate and placed at the sole of the foot. Fig.13 As shown, by simply collecting the taps from the foot movement (sizes include D=20mm and 40mm), an output voltage of -2V to 3V was successfully generated, which is better than the output signal of commercial insoles under the same test conditions (-0.6V-0.5V) and can be used for accurate detection of foot posture during movement.

[0120] The above shows and describes the basic principles, main features and advantages of the present invention. It should be noted that the exemplary description of the present invention is only a preferred embodiment of the present invention. It does not limit the present invention in any way. Without departing from the core of the present invention, any simple deformation, modification or any non-creative equivalent replacement made by other technicians in the same field to the above embodiments still belongs to the protection scope of the present invention.

Claims

1. A smart insole, characterized in that: The smart insole comprises a plurality of flexible Archimedean spiral friction nanogenerators, wherein the friction positive layer and the friction negative layer of the flexible Archimedean spiral friction nanogenerator both have Archimedean spiral linear protrusion structures; the friction positive layer and the friction negative layer are arranged face to face, and in an initial state, the friction positive layer and the friction negative layer are in a separated state; when the friction positive layer and the friction negative layer are in full contact, the Archimedean spiral linear protrusions and the corresponding concave structures of the two layers can be completely embedded; The Archimedean spiral protrusion structure has a diameter of 40 mm and a thickness of 1-1.5 mm. The triboelectric positive layer is a CNT / BTO@BC film structure triboelectric layer; the preparation method is as follows: 2 g MWCNT and 1 g BaTiO3 were dispersed in bacterial cellulose suspension and stirred at 800 rpm for 30 min to obtain CNT / BTO@BC homogeneous system. Subsequently, the CNT / BTO@BC homogeneous system was vacuum filtered and solvent evaporated at room temperature to obtain CNT / BTO@BC nanocellulose friction layer. Finally, the Archimedean spiral CNT / BTO@BC nanocellulose friction layer was obtained by polypropylene template casting, peeling and laser cutting. The triboelectric negative layer is a PEDOT:PSS@PDMS elastic triboelectric layer; the preparation method is as follows: 1.4 mL of PEDOT:PSS solution was added to 10 mL of dimethyl sulfoxide and stirred at 600 rpm for 1 h. Subsequently, 10 g of PDMS main agent was taken, 1 g of PDMS auxiliary agent and the above PEDOT:PSS solution were slowly added thereto, and magnetic stirring was performed at room temperature for 30 min. After vacuum degassing, a binary PEDOT:PSS1@PDMS elastic dispersion system was obtained. 10 mL of the above PEDOT:PSS@PDMS elastic dispersion system was cast on a polyethylene terephthalate Archimedean spiral template and cured at 75 °C for 2 h to obtain a conductive polymer / elastomer self-supporting Archimedean spiral PEDOT:PSS@PDMS elastic friction layer with precisely controlled thickness. The concentration of the PEDOT:PSS solution was 1~1.3 wt%.

2. The smart insole according to claim 1, characterized in that: The flexible Archimedean spiral friction nanogenerator also includes a first electrode layer bonded to the friction positive layer and a second electrode layer bonded to the friction negative layer; the first electrode layer is fixed on the top flexible substrate, and the second electrode layer is fixed on the bottom flexible substrate; Optionally, the top flexible substrate is connected to the bottom flexible substrate as a whole to form a flexible support skeleton.

3. The smart insole according to claim 2, characterized in that: The first electrode layer and the second electrode layer are flexible electrode layers; optionally, the first electrode layer and the second electrode layer are conductive fabrics; optionally, the flexible support skeleton is an organic glass substrate.

4. A method for improving the performance of a triboelectric nanogenerator, characterized in that: The friction nanogenerator comprises a friction positive layer and a friction negative layer, and the method is to set the friction positive layer and the friction negative layer to both have Archimedean spiral convex structures; the friction positive layer and the friction negative layer are arranged face to face, and in an initial state, the friction positive layer and the friction negative layer are in a separated state; when the friction positive layer and the friction negative layer are in full contact, the Archimedean spiral convexities and corresponding concave structures of the two layers can be completely embedded; The Archimedean spiral protrusion structure has a diameter of 40 mm and a thickness of 1-1.5 mm. The triboelectric positive layer is a CNT / BTO@BC film structure triboelectric layer; the preparation method is as follows: 2 g MWCNT and 1 g BaTiO3 were dispersed in bacterial cellulose suspension and stirred at 800 rpm for 30 min to obtain CNT / BTO@BC homogeneous system. Subsequently, the CNT / BTO@BC homogeneous system was vacuum filtered and solvent evaporated at room temperature to obtain CNT / BTO@BC nanocellulose friction layer. Finally, the Archimedean spiral CNT / BTO@BC nanocellulose friction layer was obtained by polypropylene template casting, peeling and laser cutting. The triboelectric negative layer is a PEDOT:PSS@PDMS elastic triboelectric layer; the preparation method is as follows: 1.4 mL of PEDOT:PSS solution was added to 10 mL of dimethyl sulfoxide and stirred at 600 rpm for 1 h. Subsequently, 10 g of PDMS main agent was taken, 1 g of PDMS auxiliary agent and the above PEDOT:PSS solution were slowly added thereto, and magnetic stirring was performed at room temperature for 30 min. After vacuum degassing, a binary PEDOT:PSS1@PDMS elastic dispersion system was obtained. 10 mL of the above PEDOT:PSS@PDMS elastic dispersion system was cast on a polyethylene terephthalate Archimedean spiral template and cured at 75 °C for 2 h to obtain a conductive polymer / elastomer self-supporting Archimedean spiral PEDOT:PSS@PDMS elastic friction layer with precisely controlled thickness. The concentration of the PEDOT:PSS solution was 1~1.3 wt%.

5. A device for analyzing human body motion type or motion characteristics, characterized in that: It utilizes a flexible Archimedean spiral friction nanogenerator; the friction positive layer and the friction negative layer of the flexible Archimedean spiral friction nanogenerator both have Archimedean spiral linear protrusion structures; the friction positive layer and the friction negative layer are arranged face to face, and in the initial state, the friction positive layer and the friction negative layer are in a separated state; when the friction positive layer and the friction negative layer are in full contact, the Archimedean spiral linear protrusions and corresponding concave structures of the two can be completely embedded; The Archimedean spiral protrusion structure has a diameter of 40 mm and a thickness of 1-1.5 mm. The triboelectric positive layer is a CNT / BTO@BC film structure triboelectric layer; the preparation method is as follows: 2 g MWCNT and 1 g BaTiO3 were dispersed in bacterial cellulose suspension and stirred at 800 rpm for 30 min to obtain CNT / BTO@BC homogeneous system. Subsequently, the CNT / BTO@BC homogeneous system was vacuum filtered and solvent evaporated at room temperature to obtain CNT / BTO@BC nanocellulose friction layer. Finally, the Archimedean spiral CNT / BTO@BC nanocellulose friction layer was obtained by polypropylene template casting, peeling and laser cutting. The triboelectric negative layer is a PEDOT:PSS@PDMS elastic triboelectric layer; the preparation method is as follows: 1.4 mL of PEDOT:PSS solution was added to 10 mL of dimethyl sulfoxide and stirred at 600 rpm for 1 h. Subsequently, 10 g of PDMS main agent was taken, 1 g of PDMS auxiliary agent and the above PEDOT:PSS solution were slowly added thereto, and magnetic stirring was performed at room temperature for 30 min. After vacuum degassing, a binary PEDOT:PSS1@PDMS elastic dispersion system was obtained. 10 mL of the above PEDOT:PSS@PDMS elastic dispersion system was cast on a polyethylene terephthalate Archimedean spiral template and cured at 75 °C for 2 h to obtain a conductive polymer / elastomer self-supporting Archimedean spiral PEDOT:PSS@PDMS elastic friction layer with precisely controlled thickness. The concentration of the PEDOT:PSS solution was 1~1.3 wt%.

6. The device according to claim 5, characterized in that By using a smart insole with a flexible Archimedean spiral friction nanogenerator, the difference in characteristic signals of the phase, time, peak value or frequency of the output electrical signals of each flexible Archimedean spiral friction nanogenerator is analyzed to analyze the type or characteristics of human motion.

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