Self-powered piezoelectric capacitive sensor for dynamic and static synergistic detection and method of preparation

Abstract

The application provides a self-powered piezoelectric capacitor sensor for dynamic and static cooperative detection and a preparation method thereof. The sensor comprises a piezoelectric unit for collecting dynamic signals, which comprises a top packaging layer, an upper electrode layer, a piezoelectric layer, a lower electrode layer and a central isolation layer from top to bottom; and a self-powered capacitor unit for collecting static or low-frequency signals, which comprises a bottom packaging layer, a combined lower electrode layer, a power supply layer, a radial isolation layer, a dielectric layer and a combined upper electrode layer from bottom to top, the radial isolation layer is arranged at the outer ring of the dielectric layer, and the power supply layer is arranged at the outer ring of the radial isolation layer; the lower surface of the central isolation layer of the piezoelectric unit is bonded with the upper surface of the combined upper electrode layer of the self-powered capacitor unit in a face-to-face mode, so that the piezoelectric unit and the self-powered capacitor unit form an integral structure. The application realizes dynamic and static load monitoring under the complex environment of the foot bottom by using the piezoelectric-capacitor multiple effect, and the capacitor unit is powered by the power supply layer, so that the application has the advantages of high sensitivity, low power consumption, good durability and the like.

Description

Technical Field

[0001] This invention relates to the field of flexible plantar pressure sensor technology, specifically to a self-powered voltage-capacitive sensor for dynamic and static coordinated detection and its fabrication method. Background Technology

[0002] With the development of smart devices, flexible sensors are becoming increasingly important in the field of wearable devices, especially in areas such as disease diagnosis, health monitoring, and post-operative rehabilitation. Flexible sensors provide essential assistance for patients' treatment and rehabilitation. For example, in foot and ankle injuries, patients often require long-term treatment and complex rehabilitation training, resulting in a significant financial burden. Flexible pressure sensing systems can be worn long-term in the form of insoles or socks, and can sense changes in plantar pressure in real time, providing rapid and accurate diagnostic opinions and risk predictions.

[0003] From a sensing principle perspective, the most widely used sensors in plantar pressure monitoring systems are mainly divided into piezoelectric sensors, capacitive sensors, and piezoresistive sensors. Piezoelectric sensors rely on the piezoelectric effect, where dipoles in a piezoelectric material realign and become polarized under external pressure. These sensors are characterized by self-powered operation and advantages such as simple structure, wide material availability, broad dynamic response range, and long lifespan, but they cannot monitor static loads. Furthermore, piezoelectric materials can be divided into piezoelectric ceramics and piezoelectric polymers. Although piezoelectric ceramics have high piezoelectric performance, they lack flexibility; therefore, current flexible piezoelectric sensors primarily use PVDF and its derivatives (P(VDF-TrFE), P(VDF-HFP)) and other piezoelectric polymers. Capacitive and piezoresistive sensors, on the other hand, monitor pressure by measuring changes in the resistance or capacitance of a material under load. They have advantages such as the ability to detect both dynamic and static loads, but both require an external power source.

[0004] However, due to limitations in sensing mechanisms, despite significant contributions to improving the performance of single-type sensors, issues such as the inability to monitor static pressure, narrow dynamic response range, and long response times persist. In plantar pressure monitoring, sensors need to maintain high sensitivity and accuracy in various complex motion environments, including when patients are standing still, walking, running, and climbing stairs. Furthermore, capacitive and piezoresistive sensors lack self-powered capabilities and require external power supplies, significantly sacrificing their integration and portability. Faced with these challenges, it is difficult for piezoelectric, piezoresistive, or capacitive sensors to achieve real-time monitoring of the aforementioned high dynamic and static pressure environments.

[0005] To address this issue, the inventors previously proposed a customizable, array-structured flexible piezoelectric-piezoresistive dynamic and static sensor (application number 202110399548.8). This sensor significantly reduced the processing requirements for the piezoresistive material and avoided device failure caused by the conduction of the upper and lower electrodes during electrode deposition. However, piezoresistive sensors are susceptible to environmental influences, exhibit poor long-term stability, and consume high power, making them unsuitable for the complex and long-term working environment of plantar pressure monitoring. Furthermore, their sensitivity and linearity require further improvement. A search of existing literature revealed a Chinese patent (application number 202410950523.6) disclosing a piezoelectric / resistive three-dimensional force sensor for fabric detection. This sensor's piezoelectric layer is polyvinylidene fluoride-hexafluoropropylene (PVDF-HFP) doped with barium titanate (BaTiO3) piezoelectric ceramic. However, the impedance difference between the ceramic and the polymer reduces the sensor's sensitivity, and the biotoxicity of piezoelectric ceramics makes them unsuitable for long-term use in wearable devices. In addition, the piezoresistive or capacitive components of the two dual-mechanism sensors mentioned above both require external power supply, which greatly reduces the integration and portability of the sensors.

[0006] Based on the above viewpoints, it is necessary to propose a new pressure sensor to detect dynamic and static plantar pressure in real time and realize the sensor's self-powered operation. Summary of the Invention

[0007] To address the shortcomings of existing technologies, the present invention aims to provide a self-powered voltage-capacitance sensor for dynamic and static coordinated detection and its fabrication method.

[0008] According to one aspect of the present invention, a self-powered voltage-capacitance sensor for dynamic and static coordinated detection is provided, comprising:

[0009] A piezoelectric unit is used to collect dynamic signals. The piezoelectric unit includes, from top to bottom, a top encapsulation layer, an upper electrode layer, a piezoelectric layer, a lower electrode layer, and a central isolation layer.

[0010] A self-powered capacitor unit is used to collect static or low-frequency signals. The self-powered capacitor unit includes, from bottom to top, a bottom encapsulation layer, a combined lower electrode layer, a dielectric layer, and a combined upper electrode layer. The outer ring of the dielectric layer is provided with a radial isolation layer, and the outer ring of the radial isolation layer is provided with a power supply layer.

[0011] The lower surface of the central isolation layer of the piezoelectric unit is bonded face-to-face with the upper surface of the combined upper electrode layer of the self-powered capacitor unit, so that the piezoelectric unit and the self-powered capacitor unit form an integral structure.

[0012] Optionally, the piezoelectric layer is a polyvinylidene fluoride-trifluoroethylene film doped with graphene oxide; the thickness of the piezoelectric layer is 40 micrometers to 80 micrometers.

[0013] Optionally, the dielectric layer is a polydimethylsiloxane film; the thickness of the dielectric layer is 10 micrometers to 100 micrometers.

[0014] Optionally, the power supply layer is a polyvinylidene fluoride-trifluoroethylene film doped with graphene oxide; the thickness of the power supply layer is 10 micrometers to 100 micrometers.

[0015] Optionally, the materials of the upper electrode layer, the lower electrode layer, the combined upper electrode layer, and the combined lower electrode layer are selected from any one of gold, silver, copper, and conductive polymers.

[0016] Optionally, the central isolation layer and the radial isolation layer are polyimide films, and the thickness of the central isolation layer and the radial isolation layer is 20 micrometers to 100 micrometers.

[0017] Optionally, both the top encapsulation layer and the bottom encapsulation layer are made of dichloro-p-xylene dimer; the thickness of the top encapsulation layer and the bottom encapsulation layer is 20 micrometers to 100 micrometers.

[0018] According to a second aspect of the present invention, a method for fabricating the above-described self-powered voltage-capacitance sensor for dynamic and static coordinated detection is provided, the method comprising:

[0019] Provide a piezoelectric layer;

[0020] Metal electrodes are deposited on the upper and lower surfaces of the piezoelectric layer to obtain an upper electrode layer and a lower electrode layer, respectively.

[0021] A top encapsulation layer is spin-coated onto the upper surface of the upper electrode layer;

[0022] The lower surface of the lower electrode layer is bonded to the upper surface of the central isolation layer to obtain a piezoelectric unit.

[0023] A dielectric layer, a power supply layer, and a radial isolation layer are provided respectively, and the dielectric layer, the radial isolation layer, and the power supply layer are arranged sequentially on the same plane and bonded in pairs to form a whole;

[0024] Metal electrodes are deposited on the upper and lower surfaces of the dielectric layer and the power supply layer, respectively, to obtain a combined upper electrode layer and a combined lower electrode layer;

[0025] A bottom encapsulation layer is spin-coated onto the lower surface of the combined lower electrode to obtain a self-powered capacitor unit;

[0026] The piezoelectric unit and the self-powered capacitor unit are modified to be the same size, and then the lower surface of the central isolation layer of the piezoelectric unit and the upper surface of the combined upper electrode layer of the self-powered capacitor unit are bonded together face to face to obtain a self-powered piezoelectric-capacitive sensor for dynamic and static coordinated detection.

[0027] Optionally, the method has at least one of the following features:

[0028] - The provision of the piezoelectric layer includes: preparing a polyvinylidene fluoride-trifluoroethylene film doped with graphene oxide using a solution spin coating method to obtain the piezoelectric layer;

[0029] - The dielectric layer, power supply layer and radial isolation layer are provided respectively, wherein: a polydimethylsiloxane film is prepared by solution spin coating to obtain the dielectric layer;

[0030] - The dielectric layer, power supply layer and radial isolation layer are provided respectively, wherein: a polyvinylidene fluoride-trifluoroethylene film doped with graphene oxide is prepared by solution spin coating to obtain the power supply layer.

[0031] Compared with the prior art, the present invention has at least one of the following beneficial effects:

[0032] The self-powered voltage-capacitive sensor provided by this invention integrates a piezoelectric unit and a self-powered capacitor unit face-to-face. It monitors dynamic plantar pressure signals during running, jumping, and climbing through the piezoelectric effect, and monitors static plantar pressure signals when a person is standing still through changes in the capacitance of the dielectric layer. Utilizing the multiple effects of piezoelectricity and capacitance, it achieves dynamic and static load monitoring in complex plantar environments. Simultaneously, the capacitor unit is powered by the power supply layer, resulting in high integration and portability. Compared to piezoresistive sensors, capacitive sensors have advantages such as less susceptibility to external environmental influences, higher sensitivity, lower power consumption, and better durability. Furthermore, this invention solves the problems of impedance mismatch and the need for external power supply in capacitive sensors through sensor structure design, greatly improving the overall sensor integration and making it suitable for long-term health monitoring of foot and ankle patients. Attached Figure Description

[0033] Other features, objects, and advantages of the present invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings:

[0034] Figure 1 This is a schematic diagram of the three-dimensional overall structure of a self-powered voltage-capacitance sensor for dynamic and static coordinated detection in one embodiment of the present invention;

[0035] Figure 2 This is a cross-sectional schematic diagram of a self-powered voltage-capacitance sensor for dynamic and static coordinated detection in one embodiment of the present invention;

[0036] The markings in the figure represent: 1 is the top encapsulation layer, 2 is the upper electrode layer, 3 is the piezoelectric layer, 4 is the lower electrode layer, 5 is the central isolation layer, 6 is the combined upper electrode layer, 7 is the dielectric layer, 8 is the radial isolation layer, 9 is the power supply layer, 10 is the combined lower electrode layer, and 11 is the bottom encapsulation layer. Detailed Implementation

[0037] The present invention will now be described in detail with reference to specific embodiments. These embodiments will help those skilled in the art to further understand the present invention, but do not limit the invention in any way. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention. These all fall within the scope of protection of the present invention.

[0038] The accompanying drawings illustrate various structural schematics according to embodiments of this application. These drawings are not to scale, and some details have been enlarged for clarity, and some details may have been omitted. The shapes of the various regions and layers shown in the drawings, as well as their relative sizes and positional relationships, are merely exemplary and may deviate from reality due to manufacturing tolerances or technical limitations. Furthermore, those skilled in the art can design regions / layers with different shapes, sizes, and relative positions according to actual needs, all of which fall within the scope of protection of this invention.

[0039] Reference Figure 1 and Figure 2 As shown, an embodiment of the present invention provides a self-powered piezoelectric capacitive sensor for dynamic and static coordinated detection, comprising a piezoelectric unit and a self-powered capacitor unit. The piezoelectric unit is used to acquire dynamic signals and, from top to bottom, includes a top encapsulation layer 1, an upper electrode layer 2, a piezoelectric layer 3, a lower electrode layer 4, and a central isolation layer 5. The upper electrode layer 2 is disposed on the upper surface of the piezoelectric layer 3, and the lower electrode layer 4 is disposed on the lower surface of the piezoelectric layer 3. The top encapsulation layer 1 is located on the upper surface of the upper electrode layer 2, and the central isolation layer 5 is located on the lower surface of the lower electrode layer 4. The self-powered capacitor unit is used to acquire static or low-frequency signals and, from bottom to top, includes a bottom encapsulation layer 11 and a combined lower electrode layer 10. The structure comprises a dielectric layer 7 and a combined upper electrode layer 6. The outer ring of the dielectric layer 7 is provided with a radial isolation layer 8, and the outer ring of the radial isolation layer 8 is provided with a power supply layer 9. The dielectric layer 7, the radial isolation layer 8, and the power supply layer 9 are located on the same plane. The combined upper electrode layer 6 is disposed on the upper surface of the dielectric layer 7 and the power supply layer 9, and the combined lower electrode layer 10 is disposed on the lower surface of the dielectric layer 7 and the power supply layer 9. The bottom encapsulation layer 11 is disposed on the lower surface of the combined lower electrode layer 10. The lower surface of the central isolation layer 5 of the piezoelectric unit and the upper surface of the combined upper electrode layer 6 of the self-powered capacitor unit are bonded face to face, so that the piezoelectric unit and the self-powered capacitor unit form an integral structure, which can detect dynamic and static foot pressure in real time.

[0040] In this embodiment of the invention, the piezoelectric unit and the self-powered capacitor unit are both made of high molecular polymer materials with excellent biocompatibility, good flexibility and strong environmental tolerance, so that the flexible pressure sensor can undergo corresponding deformation when subjected to external load, and generate piezoelectric signals and capacitance changes respectively, which is suitable for complex plantar pressure monitoring environments.

[0041] In some embodiments, considering that doping of conductive particles can improve the piezoelectric properties of polymer piezoelectric materials by promoting phase transformation, the piezoelectric layer 3 and the power supply layer 9 are polyvinylidene fluoride-trifluoroethylene (P(VDF-TrFE)) films doped with reduced graphene oxide (rGO), which can be prepared by solution casting. The thickness of the piezoelectric layer 3 is 40-80 micrometers. The thickness of the power supply layer 9 is 10-100 micrometers.

[0042] In the sensor described in the above embodiments of the present invention, the piezoelectric part mainly adopts PVDF-TrFE with high piezoelectric properties, wherein only a very small amount (0.1wt%) of reduced graphene oxide is used for PVDF-TrFE modification. Therefore, there is no impedance mismatch, thereby solving the problem of reduced sensitivity caused by the impedance difference between the ceramic and polymer in the piezoelectric part of the sensor in the prior art.

[0043] In some embodiments, the dielectric layer 7 is a polydimethylsiloxane (PDMS) film with excellent dielectric properties; the thickness of the dielectric layer 7 is 10 micrometers to 100 micrometers, and the thickness of the power supply layer 9 is the same as that of the dielectric layer 7. The dielectric layer 7 can be prepared by spin coating. When subjected to external forces, the dielectric layer 7 will deform, specifically by changing its thickness, which in turn causes a change in the capacitance of the dielectric layer 7. The external force can be detected by measuring the change in capacitance.

[0044] In some embodiments, the materials of the upper electrode layer 2, the lower electrode layer 4, the combined upper electrode layer 6, and the combined lower electrode layer 10 are selected from any of the materials with good conductivity, such as gold, silver, copper, and conductive polymers. The upper and lower electrode layers and the combined upper and lower electrode layers can be prepared by any of the following methods: screen printing, masking, magnetron sputtering, electron beam evaporation, or brush coating.

[0045] In some embodiments, the central insulating layer 5 and the radial insulating layer 8 are polyimide (PI) films, which have good insulating properties. The thickness of the central insulating layer 5 and the radial insulating layer 8 is 20 micrometers to 100 micrometers.

[0046] In some embodiments, both the top encapsulation layer 1 and the bottom encapsulation layer 11 are made of parylene-C dichloroxylene dimer; the thickness of the top encapsulation layer 1 and the bottom encapsulation layer 11 is 20 micrometers to 100 micrometers, thereby achieving a good encapsulation effect.

[0047] Another embodiment of the present invention provides a method for fabricating the above-mentioned self-powered voltage-capacitance sensor for dynamic and static coordinated detection. The method includes the steps of fabricating a piezoelectric unit, fabricating a self-powered capacitor unit, and bonding the two together. (Continuing with the previous section...) Figure 1 and Figure 2 The method is as follows:

[0048] S1, Provide piezoelectric layer 3;

[0049] S2. Deposit metal electrodes on the upper and lower surfaces of the piezoelectric layer 3 to obtain the upper electrode layer 2 and the lower electrode layer 4, respectively.

[0050] S3. Spin-coat the top encapsulation layer 1 onto the upper surface of the upper electrode layer 2;

[0051] S4. Bond the lower surface of the lower electrode layer to the upper surface of the central isolation layer 5 to obtain the piezoelectric unit;

[0052] S5. Provide dielectric layer 7, power supply layer 9 and radial isolation layer 8 respectively, and arrange dielectric layer 7, radial isolation layer 8 and power supply layer 9 in sequence on the same plane and bond them in pairs to form a whole;

[0053] S6. Deposit metal electrodes on the upper and lower surfaces of dielectric layer 7 and power supply layer 9 respectively to obtain combined upper electrode layer 6 and combined lower electrode layer 10.

[0054] S7. Spin-coat the bottom encapsulation layer 11 on the lower surface of the combined lower electrode to obtain a self-powered capacitor unit.

[0055] S8. Modify the piezoelectric unit and the self-powered capacitor unit to the same size, and then bond the lower surface of the central isolation layer 5 of the piezoelectric unit and the upper surface of the combined upper electrode layer 6 of the self-powered capacitor unit together face to face to obtain a self-powered voltage-capacitance sensor for dynamic and static collaborative detection.

[0056] In some embodiments, the piezoelectric layer 3 is provided by: preparing a polyvinylidene fluoride-trifluoroethylene film doped with graphene oxide using a solution spin coating method to obtain the piezoelectric layer 3.

[0057] In some embodiments, a dielectric layer 7, a power supply layer 9, and a radial isolation layer 8 are provided, wherein: a polydimethylsiloxane film is prepared by a solution spin coating method to obtain the dielectric layer 7; and a polyvinylidene fluoride-trifluoroethylene film doped with graphene oxide is prepared by a solution spin coating method to obtain the power supply layer 9.

[0058] In one specific embodiment, a method for fabricating a dynamic and static self-powered electro-capacitive flexible sensor for plantar pressure monitoring includes the following steps:

[0059] S1: Prepare an rGO / P(VDF-TrFE) thin film with a thickness of 40-80 micrometers as a piezoelectric layer;

[0060] Specifically, 0.001g rGO powder and 1g P(VDF-TrFE) powder were dissolved in dimethylformamide (DMF), mixed, and stirred with a magnetic stirrer for 1 hour. After stirring until homogeneous, the air bubbles introduced during stirring were removed in a vacuum oven. The mixture was then spin-coated onto a glass slide using a spin coating method, with the rotation speed controlled at 1200-1500 rpm and the rotation time at 1 minute. Finally, the slide was placed in a vacuum oven and cured at 60°C for 4 hours, followed by annealing at 140°C for 2 hours.

[0061] S2: Electrodes are printed on the upper and lower surfaces of the piezoelectric layer by screen printing, and a parylene-C thin film is deposited on the upper surface.

[0062] S3: Bond the PI film to the lower surface of the piezoelectric layer.

[0063] S4: The PI film is cut into a ring using laser cutting technology and fixed in the center of the glass sheet.

[0064] S5: PDMS thin film is used as the dielectric layer;

[0065] Specifically, the PDMS solution bulk and curing agent are mixed at a mass ratio of 10:1. After stirring evenly, the air bubbles introduced during stirring are removed using a vacuum oven. Then, the solution is evenly coated inside the PI ring placed on an S4 glass slide by spin coating. The rotation speed is controlled at 500 rpm-800 rpm and the rotation time is 1 minute. After removing the excess, the solution is placed in a vacuum oven and cured at 100°C for 2 hours.

[0066] S6: Use rGO / P(VDF-TrFE) film as the power supply layer. The solution preparation method is the same as S1. Pour it onto the outside of the PI ring on the S4 glass slide and spin coat it evenly. The rotation speed is controlled at 1200pm-1500rpm and the rotation time is 1 minute. Finally, put it into a vacuum oven and cure it at 60℃ for 4 hours and anneal it at 140℃ for 2 hours.

[0067] S7: The PI mask is cut using laser cutting, and electrodes are printed on the upper and lower surfaces of the dielectric layer and power supply layer respectively using screen printing. A parylene-C thin film is deposited on the lower surface.

[0068] S8: Bond the upper surface of the combined upper electrode layer of the self-powered capacitor unit prepared in S7 to the lower surface of the central isolation layer of the piezoelectric unit obtained in S3 face to face to obtain a self-powered piezoelectric-capacitive flexible plantar pressure sensor.

[0069] In the above embodiments of the present invention, the piezoelectric unit and the self-powered capacitor unit are bonded together face-to-face through the interaction of sensor structure and materials. The dynamic plantar pressure signal is monitored during running, jumping, and climbing by the piezoelectric effect, and the static plantar pressure signal is monitored when the person is standing still by the capacitance change of the dielectric layer. This multi-effect piezoelectric-capacitive approach enables dynamic and static load monitoring in complex plantar environments. Simultaneously, the capacitor unit is powered by the power supply layer, resulting in high integration and portability. This pressure sensor is less affected by the external environment and has advantages such as high sensitivity, low power consumption, high linearity, high stability, and good durability. It is suitable for complex plantar pressure monitoring environments and can be used for long-term health monitoring of foot and ankle patients.

[0070] Specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the specific embodiments described above, and those skilled in the art can make various modifications or variations within the scope of the claims, which do not affect the essence of the present invention. The above preferred features can be used in any combination without conflict.

Claims

1. A self-powered piezo-capacitive sensor for dynamic-static synergistic detection, characterized in that, The application relates to a self-powered piezoelectric capacitor sensor for dynamic and static detection. The piezoelectric unit is used for collecting dynamic signals and comprises, from top to bottom, a top packaging layer, an upper electrode layer, a piezoelectric layer, a lower electrode layer and a central isolation layer. The self-powered capacitor unit is used for collecting static or low-frequency signals and comprises, from bottom to top, a bottom packaging layer, a combined lower electrode layer, a dielectric layer and a combined upper electrode layer. The lower surface of the central isolation layer of the piezoelectric unit is bonded with the upper surface of the combined upper electrode layer of the self-powered capacitor unit in a face-to-face mode, so that the piezoelectric unit and the self-powered capacitor unit form an integral structure. The sensor monitors dynamic foot pressure signals through piezoelectric effect and monitors static foot pressure signals through the capacitance change of the dielectric layer.

2. The self-powered piezo-capacitive sensor for dynamic-static synergic detection according to claim 1, characterized in that, The piezoelectric layer is a polyvinylidene-trifluoroethylene film doped with redox graphene, and the thickness of the piezoelectric layer is 40-80 microns.

3. The self-powered piezo-capacitive sensor for dynamic-static cooperative detection of claim 1, wherein, The dielectric layer is a polydimethylsiloxane film, and the thickness of the dielectric layer is 10-100 microns.

4. The self-powered piezo-capacitive sensor for dynamic-static cooperative detection of claim 1, wherein, The power supply layer is a polyvinylidene-trifluoroethylene film doped with redox graphene, and the thickness of the power supply layer is 10-100 microns.

5. The self-powered piezo-capacitive sensor for dynamic-static cooperative detection of claim 1, wherein, The materials of the upper electrode layer, the lower electrode layer, the combined upper electrode layer and the combined lower electrode layer are selected from any one of gold, silver, copper and conductive polymers.

6. The self-powered piezo-capacitive sensor for dynamic-static cooperative detection of claim 1, wherein, The central isolation layer and the radial isolation layer are polyimide films.

7. The self-powered piezo-capacitive sensor for dynamic-static cooperative detection of claim 1, wherein, The thickness of the central isolation layer and the radial isolation layer is 20-100 microns.

8. The self-powered piezo-capacitive sensor for dynamic-static cooperative detection of claim 1, wherein, The materials of the top packaging layer and the bottom packaging layer are both dichloro-p-xylene dimer, and the thickness of the top packaging layer and the bottom packaging layer is 20-100 microns.

9. A method for the preparation of a self-powered piezo-capacitive sensor for quasi-static detection according to any one of claims 1-8, characterized in that, The application also discloses a self-powered piezoelectric capacitor sensor for dynamic and static detection. The piezoelectric layer is provided. Metal electrodes are deposited on the upper and lower surfaces of the piezoelectric layer to obtain an upper electrode layer and a lower electrode layer. A top packaging layer is spin-coated on the upper surface of the upper electrode layer. The lower surface of the lower electrode layer is bonded with the upper surface of a central isolation layer to obtain a piezoelectric unit. The dielectric layer, the radial isolation layer and the power supply layer are arranged in sequence and bonded in pairs in the same plane to form an integral structure. Metal electrodes are deposited on the upper and lower surfaces of the dielectric layer and the power supply layer to obtain a combined upper electrode layer and a combined lower electrode layer. A bottom packaging layer is spin-coated on the lower surface of the combined lower electrode to obtain a self-powered capacitor unit. The piezoelectric unit and the self-powered capacitor unit are modified to the same size, and the lower surface of the central isolation layer of the piezoelectric unit is bonded with the upper surface of the combined upper electrode layer of the self-powered capacitor unit in a face-to-face mode to obtain a self-powered piezoelectric capacitor sensor for dynamic and static detection.

10. The method of claim 9, wherein, The method has at least one of the following characteristics: The piezoelectric layer is prepared by adopting a solution spin-coating method to prepare a polyvinylidene-trifluoroethylene film doped with redox graphene. ​ - the dielectric layer, the power supply layer and the radial isolation layer are provided respectively, wherein: a polydimethylsiloxane film is prepared by a solution spin coating method to obtain the dielectric layer; - the dielectric layer, the power supply layer and the radial isolation layer are provided respectively, wherein: a polyvinylidene fluoride-trifluoroethylene film doped with reduced graphene is prepared by a solution spin coating method to obtain the power supply layer.

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