CN110572073A

CN110572073A - Mixed type friction nano generator

Info

Publication number: CN110572073A
Application number: CN201910870161.9A
Authority: CN
Inventors: 吴豪; 冯元宵; 李洋洋
Original assignee: Huazhong University of Science and Technology
Current assignee: Huazhong University of Science and Technology
Priority date: 2019-09-16
Filing date: 2019-09-16
Publication date: 2019-12-13

Abstract

The invention belongs to the technical field related to nano power generation equipment, and discloses a hybrid friction nano generator which comprises an insulating packaging layer, a grounding shielding layer, an insulating layer, a first conductive element, a first friction layer arranged in contact with the lower surface of the first conductive element, a second friction layer arranged in contact with the upper surface of the second conductive element, and a third friction layer arranged between the first friction layer and the second friction layer. When the device works, the lower surface of the first friction layer and the upper surface of the second friction layer are respectively contacted and separated with the upper surface and the lower surface of the third friction layer under the action of external force to generate relative sliding friction, and meanwhile, the friction areas of the first friction layer and the second friction layer are changed according to the difference of the magnitude and the direction of the applied external force, and alternating current pulse electric signals are output to an external circuit through the conductive element. The invention can not only effectively improve the generating efficiency and output capacity of the nano generator, but also endow the nano generating sensor with better comprehensive performance.

Description

Mixed type friction nano generator

Technical Field

The invention belongs to the related technical field of nano power generation equipment, and particularly relates to a hybrid friction nano generator.

Background

Today, with the rapid development of microelectronics and materials technologies, a large number of novel multifunctional and highly integrated microelectronic devices are continuously developed, and show unprecedented application prospects in various fields in people's daily life. However, the power supply systems matched to these microelectronic devices have been relatively slow to develop. At present, various researches around development of new energy and recycling of renewable energy are actively conducted around the world, and therefore, it is very important to develop a technology capable of converting naturally occurring mechanical energy such as motion and vibration into electric energy.

In recent years, the nano generator based on the triboelectric effect is developed rapidly, and a very promising approach is provided for converting mechanical energy into electric energy to drive electronic devices by virtue of high-efficiency output, simple process and stable performance of the nano generator. According to retrieval, some technical schemes of the nano-generator based on the tribostatic effect have been proposed in the prior art. For example, CN201810714708.1 discloses a friction nano-generator, in which first to fourth friction layers are coaxially arranged, and through the contact of the first friction layer and the second friction layer and the contact of the third friction layer and the fourth friction layer, relative rotation generates friction, so that the generator starts to generate electricity. For another example, CN201510232639.7 discloses a rotary friction nano-generator, which comprises at least one set of first friction unit and second friction unit, and is in contact friction with each of the first and second friction units through a third component, so that triboelectric charges are generated on the two friction units respectively. Furthermore, some nanogenerator products are disclosed in the prior art that are not in the form of shafts but in the form of stacks.

however, further studies have shown that the above prior art still has the following drawbacks or disadvantages: firstly, no matter the friction power generation equipment adopts a laminated form or an axial form, the same friction layer of the friction power generation equipment only has one polarity, so that the number, the specific arrangement mode, the overall configuration and the like of the friction layers are greatly limited; secondly, there is a need for improvement in output efficiency and output performance, and it is necessary to increase compatibility with a working environment. Accordingly, there is a need in the art for further improvements that provide better coverage of the various complex needs in practical applications.

Disclosure of Invention

In view of the above drawbacks and needs of the prior art, an object of the present invention is to provide a hybrid friction nano-power generation sensor, wherein the basic configuration and the operation principle of the friction nano-power generation sensor are redesigned, so that a friction layer material in a single power generation device can have both positive and negative polarities and can be switched as required, and the friction layer material can more sensitively convert mechanical energy applied to a friction nano-power generator into electrical energy compared with the existing device, and has the advantages of compact structure, convenient operation and control, and capability of effectively improving the power generation efficiency and output capability of the nano-power generator.

According to the present invention, there is provided a hybrid type friction nano electric power generating sensor, characterized in that the friction nano electric power generating sensor is entirely of a stacked structure and includes, in order from top to bottom along a height direction, a first insulating encapsulation layer, a first ground shield layer, a first insulating layer, a first conductive element, a first friction layer, a third friction layer, a second conductive element, a second insulating layer, a second ground shield layer, and a second insulating encapsulation layer, wherein:

The lower surface of the first friction layer and the upper surface of the second friction layer are used for being respectively contacted and separated with the corresponding surface of the third friction layer in operation, relative sliding friction is generated, the friction area is changed, and therefore surface charge transfer on the friction layers is triggered, the surface charge transfer flows to the first conducting element and the second conducting element through the guiding circuit to generate a transient circuit, and accordingly alternating current pulse electric signals are output to an external circuit through the conducting elements.

It is further preferable that the rubbing electrode orders of the first, second and third rubbing layers are different from each other, that is, different from each other in the degree of attraction to electric charges, and the rubbing electrode order of the third rubbing layer is between the first and second rubbing layers.

As a further preference, the lower surface of the first friction layer and/or the upper surface of the second friction layer and/or the upper and lower surfaces of the third friction layer are preferably distributed with micro-or sub-micro-scale microstructures; and these microstructures are preferably selected from the group consisting of nanowires, nanotubes, nanoparticles, nano-grooves, micro-grooves, nano-cones, micro-cones, nano-spheres or micro-spheres.

As a further preference, the lower surface of the first friction layer and/or the upper surface of the second friction layer and/or the upper and lower surfaces of the third friction layer are preferably provided with a decoration or coating of nanomaterial.

it is further preferable that the lower surface of the first friction layer and/or the upper surface of the second friction layer and/or the upper and lower surfaces of the third friction layer are chemically modified so that a functional group which easily gains electrons, for example, a functional group such as an acyl group, a carboxyl group, a nitro group, or a sulfonic acid group, is introduced into the material of the lower surface of the first friction layer and/or the lower surface of the third friction layer, and/or a functional group which easily loses electrons, for example, a functional group such as an amino group, a hydroxyl group, or an alkoxy group, is introduced into the material of the upper surface of the second friction layer and/or the material of the upper surface of the third friction layer.

As a further preference, the lower surface of the first friction layer and/or the upper surface of the second friction layer and/or the upper and lower surfaces of the third friction layer are chemically modified so that a negative charge is introduced at the lower surface material of the first friction layer and/or the lower surface of the third friction layer and/or a positive charge is introduced at the upper surface material of the second friction layer and/or the upper surface of the third friction layer. Furthermore, the chemical modification is achieved by means of chemical bonding to introduce charged groups.

As a further preference, the lower surface of the first friction layer and/or the upper surface of the second friction layer and/or the upper and lower surfaces of the third friction layer are preferably further provided with a plurality of friction units arranged in discrete arrays, and the arrangement pattern of the respective friction units on the oppositely disposed friction layers is kept in correspondence, and it is ensured that, in operation, each friction unit on the lower surface of the first friction layer is in partial contact with at least one friction unit on the upper surface of the third friction layer, and each friction unit on the upper surface of the second friction layer is in partial contact with at least one friction unit on the lower surface of the third friction layer.

As a further preference, the first and second conductive elements are films or sheets; the first friction layer, the second friction layer and the third friction layer are preferably films or sheets.

As a further preference, the first friction layer, the second friction layer, the third friction layer, the first conductive element, the second conductive element are hard or flexible.

Preferably, the cross section of the first friction layer, the first conductive element, the second conductive element and the second friction layer is preferably in a semi-elliptical ring shape or a semi-circular ring shape; the cross section of the third friction layer is preferably rectangular, circular or elliptical, and the cross sections of the insulating packaging layer and the grounding shielding layer are preferably elliptical or circular.

Preferably, when the hybrid friction nano-generator is in a non-operating state, the lower surface of the first friction layer is separated from the upper surface of the third friction layer, and the upper surface of the second friction layer is separated from the lower surface of the third friction layer; in the working state, the lower surface of the first friction layer is in contact with the upper surface of the third friction layer and generates relative friction, and the upper surface of the second friction layer is in contact with the lower surface of the third friction layer and generates relative friction.

As a further preference, the third friction layer is made of a conductive material, and the conductive material is preferably selected from indium tin oxide, graphene, silver nanowire film, metal, alloy, conductive oxide or conductive polymer; wherein the metal is gold, silver, platinum, palladium, aluminum, nickel, copper, titanium, chromium, tin, iron, manganese, molybdenum, tungsten or vanadium; the alloy is an aluminum alloy, a titanium alloy, a magnesium alloy, a beryllium alloy, a copper alloy, a zinc alloy, a manganese alloy, a nickel alloy, a lead alloy, a tin alloy, a cadmium alloy, a bismuth alloy, an indium alloy, a gallium alloy, a tungsten alloy, a molybdenum alloy, a niobium alloy, or a tantalum alloy.

As a further preference, the lower surface of the first friction layer and the upper surface of the second friction layer are preferably made of an insulating material or a semiconductor material, wherein the insulating material is selected from the group consisting of aniline formaldehyde resin, polyoxymethylene, ethyl cellulose, polyamide nylon, wool and its fabric, silk and its fabric, paper, polyethylene glycol succinate, cellulose acetate, polyethylene glycol adipate, polydiallyl phthalate, regenerated cellulose sponge, cotton and its fabric, polyurethane elastomer, styrene-acrylonitrile copolymer, styrene-butadiene copolymer, wood, hard rubber, acetate, rayon, polymethyl methacrylate, polyvinyl alcohol, polyester, polyisobutylene, polyurethane elastic sponge, polyethylene terephthalate, polyvinyl butyral, butadiene-acrylonitrile copolymer, polyethylene terephthalate, polyvinyl butyral, polyethylene terephthalate, Neoprene, natural rubber, polyacrylonitrile, poly (vinylidene chloride-CO-acrylonitrile), poly bisphenol a carbonate, polychlorinated ether, polyvinylidene chloride, poly (2, 6-dimethyl polyphenylene oxide), polystyrene, polyethylene, polypropylene, poly diphenylpropane carbonate, polyethylene terephthalate, polyimide, polyvinyl chloride, polydimethylsiloxane, polychlorotrifluoroethylene, polytetrafluoroethylene, or parylene; and the semiconductor material is selected from the following undoped materials: silicon, germanium, group III and V compounds, group II and VI compounds, solid solutions consisting of group III-V compounds and group II-VI compounds, amorphous glass semiconductors and organic semiconductors, wherein the group III and V compounds are selected from gallium arsenide and gallium phosphide; the group II and VI compounds are selected from the group consisting of thiofides and zinc sulfides; the solid solution consisting of group III-V compounds and group II-VI compounds is selected from gallium aluminum arsenic and gallium arsenic phosphorus.

as a further preference, the material of the lower surface of the first friction layer and the upper surface of the second friction layer is preferably non-conductive oxide, semiconductor oxide or complex oxide, including silicon oxide, aluminum oxide, manganese oxide, chromium oxide, iron oxide, copper oxine-oxide, zinc oxide, BiO₂And Y₂O₃。

As a further preference, the lower surface of the first friction layer and the lower surface of the third friction layer are preferably a friction electrode sequence material with negative polarity, selected from polystyrene, polyethylene, polypropylene, poly diphenylpropane carbonate, polyethylene terephthalate, polyimide, polyvinyl chloride, polydimethylsiloxane, polychlorotrifluoroethylene, polytetrafluoroethylene and parylene.

Preferably, the upper surfaces of the second and third friction layers are preferably positive friction electrode sequence materials selected from aniline formaldehyde resin, polyoxymethylene, ethyl cellulose, polyamide nylon, wool and its fabric, silk and its fabric, paper, polyethylene glycol succinate, cellulose acetate, polyethylene glycol adipate, polydiallyl phthalate, regenerated cellulose sponge, cotton and its fabric, polyurethane elastomer, styrene-acrylonitrile copolymer, styrene-butadiene copolymer, wood, hard rubber, acetate, rayon, polymethylmethacrylate, polyvinyl alcohol, polyester, copper, aluminum, gold, silver, steel, and silicon.

That is, the triboelectric series material with the negative polarity on the lower surface of the third friction layer is a positive-polarity triboelectric series material with respect to the upper surface material of the second friction layer, and the triboelectric series material with the positive polarity on the upper surface of the third friction layer is a negative-polarity triboelectric series material with respect to the lower surface material of the first friction layer.

In general, compared with the prior art, the paper-based flexible touch sensor and the manufacturing method thereof according to the present invention mainly have the following technical advantages:

1. new breakthrough in structure and principle. The hybrid friction generator is provided with three friction layers, and the third friction layer can have positive and negative polarities simultaneously in a working state so as to form alternating current pulse signal output between the first conductive element and the second conductive element, so that the hybrid friction generator is different from the traditional friction generator in power generation principle and provides a brand new design idea of the friction generator.

2. The output performance is more excellent. The upper surface of the first friction layer and the lower surface of the second friction layer in the generator are physically or chemically modified, and a nanostructure pattern is introduced or a nanometer material is coated, so that the contact charge density generated when the three friction layers contact and slide relatively under the action of external force of the friction nanometer generator can be further improved, and the output capacity of the generator is improved.

3. the energy is utilized efficiently. The generator does not need large-scale and high-strength energy input, and only needs the input mechanical energy to drive the relative sliding among the first friction layer, the second friction layer and the third friction layer, so that the mechanical energy with various strengths generated in the nature and the daily life of people can be effectively collected and converted into electric energy, and the efficient utilization of the energy is realized; moreover, the friction nano generator simultaneously comprises a plurality of generating elements, so that the output power can be greatly improved.

4. Simple structure, light weight, portability and high compatibility. The generator of the invention does not need parts such as a magnet, a coil, a rotor and the like, has simple structure, small volume, convenient manufacture and low cost, can be arranged on various devices which can enable the first friction layer, the second friction layer and the third friction layer to generate relative sliding, does not need special working environment, and has high compatibility.

5. Is less interfered by the outside. The friction generator is additionally provided with the grounding shielding layer, and the grounding treatment of the friction generator can effectively shield the interference of external environmental factors during working, so that the output performance of the device is more excellent. When the generator is used as a sensor, the sensitivity is higher.

6. Has wide application. The generator can be used as a small power source and can also be used for high-power generation; in addition, the friction nano generator can provide direct current output through a bridge rectifier circuit so as to be used by equipment requiring direct current; furthermore, the generator of the present invention can also be used as a sensor, for example, as a pressure sensor or a strain sensor applied to a safety belt to monitor the driving state of a driver in real time.

Drawings

FIG. 1 is a schematic view of the overall construction of a hybrid triboelectric nano-power sensor in accordance with a preferred embodiment of the present invention;

FIG. 2 is a schematic sectional view for specifically explaining the operation principle of the frictional nanogeneration sensor shown in FIG. 1;

FIG. 3 is a schematic structural view of a hybrid triboelectric nano-power sensor in accordance with another preferred embodiment of the present invention;

FIG. 4 is a graph of the open circuit voltage output for the triboelectric nanogenerator shown in FIG. 1 at 2.5mm cyclic compression;

FIG. 5 is a graph of the open circuit voltage output of the triboelectric nanogenerator shown in FIG. 3 at cyclic compression and a pressure of 5N;

Fig. 6 is a schematic view for exemplarily showing driving state monitoring for a safety belt after the friction nano-generator of the present invention is arrayed.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

The invention provides a friction nano generator with a simple structure, which can convert the naturally existing mechanical energy such as motion, vibration and the like into electric energy and can provide a matched power supply for a micro electronic device or be used as a sensor. The friction nano generator utilizes the phenomenon of surface charge transfer generated when materials with different polarities in a friction electrode sequence are contacted, and converts mechanical energy of external force into electric energy.

The term "rubbing electrode sequence" as used herein refers to the sequence of materials according to their degree of attraction to electric charges, in which negative charges on the rubbing surfaces are transferred from the surfaces of the materials with positive polarity to the surfaces of the materials with negative polarity at the instant of mutual rubbing of the two materials. To date, there is no unified theory that fully explains the mechanism of charge transfer, which is generally believed to be related to the surface work function of the material, by the transfer of electrons or ions at the interface. It should be noted that the rubbing electrode sequence is only an empirical statistical result, i.e. the farther the two materials are apart in the sequence, the greater the probability that the positive and negative charges generated after contact will correspond to the sequence, and the actual result will be influenced by various factors, such as the surface roughness of the materials, the ambient humidity, and whether there is relative friction. It is further noted that the transfer of charge does not require relative friction between the two materials, as long as there is mutual contact.

The "contact charge" in the present invention refers to the charge carried on the surface of two materials with different polarity of the electrode sequence, which are rubbed and separated, and it is generally considered that the charge is only distributed on the surface of the material, and the maximum depth of the distribution is about 10 nm. It should be noted that the sign of the contact charge is the sign of the net charge, that is, there may be a region where negative charges are accumulated in a local area on the surface of the material having positive contact charge, but the sign of the net charge on the whole surface is positive.

For convenience of explanation, the principles of the present invention, the selection of components, and the range of materials will be described below with reference to the exemplary structure of fig. 1, but it should be apparent that the present invention is not limited to the embodiment shown in fig. 1, but can be applied to all technical solutions disclosed in the present invention.

First exemplary embodiment:

Fig. 1 is a typical structure of a hybrid friction nano-generator according to the present invention, including: the package structure comprises an insulating packaging layer 10, a ground shield layer 20, an insulating layer 30, a first conductive element 401, a first friction layer 501 placed in contact with the lower surface of the first conductive element, a second conductive element 402, a second friction layer 502 placed in contact with the upper surface of the second conductive element, and a third friction layer 60 located between the first friction layer and the second friction layer. The third friction layer 60 is made of conductive material, so that an insulating layer 30 is added in the middle. When the lower surface of the first friction layer 501 and the upper surface of the third friction layer 60 rub against each other, the upper surface of the second friction layer 502 and the lower surface of the third friction layer 60 rub against each other, and the friction areas of the two friction layers change due to the external force, an electrical signal can be output to an external circuit through the first conductive element 401 and the second conductive element 402 due to the difference in the electrode sequence of friction among the material of the first friction layer 501, the material of the second friction layer 502, and the third friction layer 60.

The working principle of the friction nano-generator of the invention is shown in figure 2. In fig. 2(a) to 2(d), when the lower surface of the first friction layer 501 and the upper surface of the third friction layer 60 are relatively slid and rubbed by the pressure applied to the insulating encapsulation layer 10, and the upper surface of the second friction layer 502 and the lower surface of the third friction layer 60 are relatively slid and rubbed, and the friction areas of the two friction layers are changed due to the difference in the magnitude and direction of the applied pressure, the friction process causes the surface charge transfer of the friction layers due to the difference in the friction electrode order among the material of the first friction layer 501, the material of the second friction layer 502, and the third friction layer 60.

Referring to fig. 2(b), in order to shield an electric field formed by surface charges generated by friction remaining in the first and second friction layers 501 and 502 due to the gradual increase of the contact area of the friction layer region, free electrons in the second conductive member 402 flow to the first conductive member 401 through an external circuit, generating a transient current.

Referring to fig. 2(d), when the external force is released or in the reverse direction, in order to shield an electric field formed by surface charges generated by friction remaining in the first and second friction layers 501 and 502 due to the gradual reduction of the contact area of the friction layer region, electrons in the first conductive member 401 flow back to the second conductive member 402, thereby giving a current in the reverse direction.

the first friction layer 501 and the second friction layer 502 are respectively made of materials with different triboelectric characteristics, which means that the two friction layers are at different positions in the friction electrode sequence, so that the two friction layers can generate contact charges on the surfaces during the friction process. Both conventional insulating materials and semiconductor materials have triboelectric characteristics, and can be used as materials for preparing the first friction layer 501 and the second friction layer 502 of the present invention.

The insulation may be selected from a number of commonly used organic polymeric and natural materials including aniline formaldehyde resin, polyoxymethylene, ethyl cellulose, polyamide nylon, wool and fabrics, silk and fabrics, paper, polyethylene glycol succinate, cellulose acetate, polyethylene glycol adipate, polydiallyl phthalate, regenerated cellulose sponge, cotton and fabrics, polyurethane elastomers, styrene-acrylonitrile copolymers, styrene-butadiene copolymers, wood, hard rubber, acetate, rayon, polymethyl methacrylate, polyvinyl alcohol, polyester, polyisobutylene, polyurethane elastic sponge, polyethylene terephthalate, polyvinyl butyral, butadiene-acrylonitrile copolymers, neoprene, natural rubber, polyacrylonitrile, poly (vinylidene chloride-CO-acrylonitrile), poly (ethylene-CO-butylene oxide), poly (ethylene-CO-butylene oxide), poly (ethylene, Poly bisphenol a carbonate, polychlorinated ether, polyvinylidene chloride, poly (2, 6-dimethyl polyphenylene oxide), polystyrene, polyethylene, polypropylene, poly diphenylpropane carbonate, polyethylene terephthalate, polyimide, polyvinyl chloride, polydimethylsiloxane, polychlorotrifluoroethylene, polytetrafluoroethylene, and parylene.

Commonly used semiconductor materials are selected from the following undoped materials: silicon, germanium, group III and V compounds such as gallium arsenide and gallium phosphide, and the like; group II and VI compounds such as sulfuryl, zinc sulfide, etc.; solid solutions composed of group III-V compounds and group II-VI compounds, such as gallium aluminum arsenic and gallium arsenic phosphorus; in addition to the above crystalline semiconductor, an amorphous glass semiconductor, an organic semiconductor, or the like can be selected; non-conductive oxides, semiconductive oxides or complex oxides may also be used as the tribolayer material, including silicon oxide, aluminum oxide, manganese oxide, chromium oxide, iron oxide, copper oxide, zinc oxide, BiO₂And Y₂O₃。

The thicknesses of the first friction layer 501 and the second friction layer 502 have no significant influence on the implementation of the present invention, and only the factors such as the strength of the friction layers and the power generation efficiency need to be comprehensively considered in the setting process. The preferred rubbing layer of the present invention is a thin layer with a thickness of 50nm to 2cm, preferably 100nm to lcm, more preferably 1u m to 5mm, more preferably 10u m to 2mm, which is suitable for all embodiments of the present invention.

The third friction layer 60 is made of a conductive material, and its triboelectric series should be between that of the first friction layer 501 and the second friction layer 502, the conductive material includes: indium tin oxide, graphene, silver nanowire films, metals, alloys, conductive oxides, or conductive polymers; wherein the metal is gold, silver, platinum, palladium, aluminum, nickel, copper, titanium, chromium, tin, iron, manganese, molybdenum, tungsten or vanadium; the alloy is an aluminum alloy, a titanium alloy, a magnesium alloy, a beryllium alloy, a copper alloy, a zinc alloy, a manganese alloy, a nickel alloy, a lead alloy, a tin alloy, a cadmium alloy, a bismuth alloy, an indium alloy, a gallium alloy, a tungsten alloy, a molybdenum alloy, a niobium alloy, or a tantalum alloy.

The first conductive element 401, the second conductive element 402, and the ground shield 20 only need to have a conductive property, and may be selected from indium tin oxide, graphene, a silver nanowire film, a metal, an alloy, a conductive oxide, or a conductive polymer; wherein the metal is gold, silver, platinum, palladium, aluminum, nickel, copper, titanium, chromium, tin, iron, manganese, molybdenum, tungsten or vanadium; the alloy is an aluminum alloy, a titanium alloy, a magnesium alloy, a beryllium alloy, a copper alloy, a zinc alloy, a manganese alloy, a nickel alloy, a lead alloy, a tin alloy, a cadmium alloy, a bismuth alloy, an indium alloy, a gallium alloy, a tungsten alloy, a molybdenum alloy, a niobium alloy, or a tantalum alloy.

The conductive elements may be films, sheets or plates, preferably films and sheets.

The first conductive element 401 and the second conductive element 402 may be connected to an external circuit through a wire or a metal film.

The present invention does not limit that the first friction layer 501 and the second friction layer 502 are necessarily hard materials, but flexible materials can be selected, because the hardness of the materials does not affect the sliding friction effect between the two, and those skilled in the art can select the materials according to actual situations. Moreover, the generator made of flexible material has the advantage that the soft and light friction layer is deformed by a slight external force, and the deformation causes the relative displacement of the two friction layers, thereby outputting an electrical signal outwards through sliding friction. The use of flexible materials allows the nanogenerator of the invention to have a very wide range of applications also in the fields of biology and medicine. During the use process, a high polymer material with ultrathin, soft, elastic and/or transparent properties can be used as a substrate for packaging so as to facilitate the use and improve the strength. Obviously, all the structures disclosed in the present invention can be made of corresponding super-soft and elastic materials, so as to form a flexible nano-generator, which will not be described in detail herein, but various designs derived therefrom should be included in the protection scope of the present patent.

For reasons of space and not intended to be exhaustive, and it is to be understood that the specific materials listed herein are not to be construed as limiting the scope of the invention since other similar materials may be readily selected by those skilled in the art based on the triboelectric properties of the materials in view of the teachings of the invention.

It has been found experimentally that the greater the difference in triboelectric properties between the friction layer contacting surface materials, the stronger the electrical signal output by the generator. Therefore, the friction layers contacting with each other can be prepared by selecting appropriate materials according to actual needs. A triboelectric electrode sequence material having a negative polarity, preferably selected from the group consisting of polystyrene, polyethylene, polypropylene, poly diphenylpropane carbonate, polyethylene terephthalate, polyimide, polyvinyl chloride, polydimethylsiloxane, polychlorotrifluoroethylene, polytetrafluoroethylene and parylene; the material of the triboelectric electrode sequence with positive polarity is preferably selected from the group consisting of aniline formaldehyde resin, polyoxymethylene, ethylcellulose, polyamide nylon 11, polyamide nylon 66, wool and its fabrics, silk and its fabrics, paper, polyethylene glycol succinate, cellulose acetate, polyethylene glycol adipate, polydiallyl phthalate, regenerated cellulose sponge, cotton and its fabrics, polyurethane elastomers, styrene-acrylonitrile copolymers, styrene-butadiene copolymers, wood, hard rubber, acetate, rayon, polymethyl methacrylate, polyvinyl alcohol, polyester.

The surface of the first friction layer 501 and/or the second friction layer 502 which are in contact with each other may be chemically modified, so that the amount of charge transferred at the moment of contact can be further increased, and the contact charge density and the output power of the generator can be increased. Chemical modification is divided into two types:

One method is to introduce a functional group which is more prone to lose electrons (i.e. a strong electron-donating group) on the surface of a material with positive polarity or introduce a functional group which is more prone to obtain electrons (a strong electron-withdrawing group) on the surface of a material with negative polarity, for the surface materials of the first friction layer 501 and/or the second friction layer 502 which are in contact with each other, so that the transfer amount of charges during mutual sliding can be further increased, and the triboelectric charge density and the output power of the generator can be increased. The strong electron-donating groups include amino, light groups, alkoxy, and the like; the strong electron-withdrawing group includes acyl, carboxyl, nitro, sulfonic acid group, etc. The functional group can be introduced by a conventional method such as plasma surface modification. For example, a mixture of oxygen and nitrogen may be used to generate plasma at a certain power to introduce amino groups on the surface of the friction layer material.

Another method is to introduce positive charges on the surface of the rubbing layer material with positive polarity and negative charges on the surface of the rubbing layer material with negative polarity. In particular, the bonding can be achieved by means of chemical bonding. For example, the surface of a Polydimethylsiloxane (PDMS) friction layer may be modified with Tetraethoxysilane (TEOS) by hydrolysis-condensation (sol-gel), so as to be negatively charged. Gold nanoparticles having cetyltrimethylammonium bromide (CTAB) on the upper surface may be modified by gold-sulfur bonding on the metallic gold thin film layer, and the entire friction layer may be positively charged because cetyltrimethylammonium bromide is a cation. Those skilled in the art can select suitable modifying materials to bond with the friction layer according to the electron gaining and losing properties and the surface chemical bond types of the friction layer material to achieve the purpose of the present invention, and therefore such modifications are within the protection scope of the present invention.

Second exemplary embodiment:

Fig. 3 is another exemplary structure of the hybrid friction nano-generator of the present invention, including: insulating encapsulation layers 101 and 102, ground shield layers 201 and 202, insulating layers 301 and 302, pads 701-704, first conductive element 401, first friction layer 501 placed in contact with the lower surface of the first conductive element, second conductive element 402, second friction layer 502 placed in contact with the upper surface of the second conductive element, and third friction layer 60 located between the first friction layer and the second friction layer. Wherein the third friction layer 60 is a non-conductive material. When pressure is applied to the insulating encapsulation layer, the lower surface of the first friction layer 501 and the upper surface of the third friction layer 60 rub against each other, the upper surface of the second friction layer 502 and the lower surface of the third friction layer 60 rub against each other, and the rubbing areas of the two rubbing against each other are changed, an electrical signal can be output to an external circuit through the first conductive element 401 and the second conductive element 402 due to the difference in the electrode sequence of rubbing among the material of the first friction layer 501, the material of the second friction layer 502, and the third friction layer 60.

This embodiment has the same general structure as the embodiment shown in fig. 1, except that the third friction layer 60 is a non-conductive material and does not need to be separated by an insulating layer in the middle; the upper and lower insulating packaging layers, the grounding shielding layer and the insulating layer are separated and not integrated; in order to ensure the friction layers are separated from each other in an initial state (without external force), spacers 701-704 are added between the respective friction layers. The power generation principle of the friction generator with the configuration is basically the same as that shown in fig. 2. In addition, the cross-sectional view of the entire device is changed from an oval shape to a rectangular shape.

The materials of the pads 701-704 are preferably selected from conventional insulating materials and semiconductor materials.

The insulation may be selected from a number of commonly used organic polymeric and natural materials including aniline formaldehyde resin, polyoxymethylene, ethyl cellulose, polyamide nylon 11, polyamide nylon 66, wool and its fabrics, silk and its fabrics, paper, polyethylene glycol succinate, cellulose acetate, polyethylene glycol adipate, polydiallyl phthalate, regenerated cellulose sponge, cotton and its fabrics, polyurethane elastomers, styrene-acrylonitrile copolymers, styrene-butadiene copolymers, wood, hard rubber, acetate, rayon, polymethyl methacrylate, polyvinyl alcohol, polyester, polyisobutylene, polyurethane elastic sponge, polyethylene terephthalate, polyvinyl butyral, butadiene-acrylonitrile copolymers, neoprene, natural rubber, polyacrylonitrile, poly (vinylidene chloride-CO-acrylonitrile), poly (ethylene-CO-butylene phthalate), poly (ethylene-CO-styrene), poly (ethylene-butylene terephthalate), poly (ethylene, Poly bisphenol a carbonate, polychlorinated ether, polyvinylidene chloride, poly (2, 6-dimethyl polyphenylene oxide), polystyrene, polyethylene, polypropylene, poly diphenylpropane carbonate, polyethylene terephthalate, polyimide, polyvinyl chloride, polydimethylsiloxane, polychlorotrifluoroethylene, polytetrafluoroethylene, and parylene;

Commonly used semiconductor materials are selected from the following undoped materials: silicon, germanium, group III and V compounds such as gallium arsenide and gallium phosphide, and the like; group II and VI compounds such as sulfuryl, zinc sulfide, etc.; solid solutions composed of group III-V compounds and group II-VI compounds, such as gallium aluminum arsenic and gallium arsenic phosphorus; in addition to the above crystalline semiconductor, an amorphous glass semiconductor, an organic semiconductor, or the like can be selected; non-conductive oxides, semiconductive oxides or complex oxides may also be used as the tribolayer material, including silicon oxide, aluminum oxide, manganese oxide, chromium oxide, iron oxide, copper oxide, zinc oxide, BiO₂And Y₂O₃；

the thickness of the spacers 701-704, which serve to isolate the frictional layer, should be selected according to the structure and size of the device. The preferred thickness according to the invention is between 0.5mm and 2cm, preferably between 1mm and 5mm, which is suitable for all the technical solutions according to the invention.

The width of the pads 701-704 should be smaller than the width of each friction layer to ensure that some areas of each friction layer contact each other and generate friction when subjected to external force.

In the process of continuously contacting and separating the first friction layer 501, the second friction layer 502 and the third friction layer 60 by the applied external force, the first conductive element 401 and the second conductive element 402 connected with the external circuit output alternating current pulse electrical signals with alternating directions to the external circuit, so that the conversion from mechanical energy to electrical energy is realized.

example 1:

This example selects the triboelectric nano-generator configuration shown in fig. 1. Insulating packaging layer 10 chooses thickness to be 3um, the size is polyethylene terephthalate (PET) film of 13mm 26mm, the thickness of ground shield 20 chooses for use is 5um, the size is copper film of 13mm 26mm, the thickness of insulating layer 30 chooses for use is 3um, the size is Polyimide (PI) film of 13mm 26mm, first conductive element 401 chooses for use thickness to be 5um, the size is copper foil of 12.5mm, first frictional layer 501 chooses for use thickness to be 1um, the size is Polytetrafluoroethylene (PTFE) film of 12mm, the size is 5um for use to the second conductive element, the size is copper film of 12.5mm, the thickness of second frictional layer 502 chooses for use is 2um, the size is letter paper of 12mm, the thickness of third frictional layer 60 chooses for use is 1um, the size is 10 mm. In the initial state (without external force), the maximum distance between the first friction layer PTFE and the second friction layer paper and the third friction layer is 3 mm. In addition, the PTFE surface of the first friction layer is subjected to conductive coupled plasma etching (ICP) treatment, and a nano-pillar array is formed.

After the metal copper foils of the first conductive element and the second conductive element are led out with the leads, the linear motor is used for controlling the acrylic sheet to compress the PET of the device insulation packaging layer in a reciprocating mode, when the maximum compression amount of the whole device is 2.5mm, the lower surface of the PTFE of the first friction layer and the upper surface of the aluminum foil of the third friction layer are subjected to relative friction, the upper surface of the paper of the second friction layer and the lower surface of the aluminum foil of the third friction layer are subjected to relative friction, the friction area is periodically changed, the friction nano-generator is driven to work, and the generated open-circuit voltage output graph is shown in figure 4.

Example 2:

This embodiment is selected from the triboelectric nano-generator configuration shown in fig. 3. The material types and thicknesses of the various layers of this embodiment are substantially the same as those of embodiment 1, except that the second frictional layer 502 is a Polyamide (PA) film having a thickness of 2um, and the third frictional layer 60 is a polyethylene terephthalate (PET) film having a thickness of 3 um. The pads 701-704 are 1cm by 6mm in size, and the remaining layers are 1cm by 1cm in length and width. In the initial state (without external force), the distance between the first friction layer PTFE and the second friction layer PA and the third friction layer is 6 mm. In addition, the PTFE surface of the first friction layer is subjected to conductive coupled plasma etching (ICP) treatment, and a nano-pillar array is formed.

After the metal copper foils of the first conductive element and the second conductive element are led out with wires, the linear motor is used for controlling the acrylic sheet to compress the device insulating packaging layer in a reciprocating mode, when the maximum pressure borne by the whole device is 5N, the lower surface of the PTFE (polytetrafluoroethylene) of the first friction layer and the upper surface of the PET (polyethylene terephthalate) of the third friction layer are subjected to relative friction, the upper surface of the polyamide film of the second friction layer and the lower surface of the PET of the third friction layer are subjected to relative friction, the friction area is periodically changed, the friction nano-generator is accordingly promoted to work, and the generated open-circuit voltage output graph is shown in figure 5.

the friction nano generator can utilize translational kinetic energy to enable the generator to generate electric energy, provides power for small-sized electric appliances, does not need power supplies such as batteries and the like, and is a generator convenient to use. In addition, because friction can be formed by a plurality of movements existing in the nature and human life, the power generation method, the nano generator based on the independent friction layer and the generator set provided by the invention can be used for collecting mechanical energy in a plurality of living environments, such as walking of people, traveling of vehicles and the like. The friction nano generator is simple and convenient in preparation method and low in preparation cost, and is a friction nano generator with wide application range.

The friction nano generator of the invention can also be used as a sensor, for example, for measuring the mass of an object, measuring stress, strain and the like, and can also be used for monitoring the driving posture of a driver, the friction generator in example 1 is arrayed and placed on a safety belt, the specific placement position of the safety belt is shown in fig. 6, during the driving process, due to the difference of the action and posture of the driver, the safety belt is intermittently contacted with the shoulder and the waist of a human body, the contact area is changed, the lower surface of the first friction layer PTFE and the upper surface of the third friction layer aluminum foil are relatively rubbed, the upper surface of the second friction layer paper and the lower surface of the third friction layer aluminum foil are relatively rubbed, the first conductive element and the second conductive element are connected through an electrode lead, so as to form a passage, generate voltage and current, and draw a voltage distribution diagram of the sensor during the driving process, the driving action of the driver can be judged according to the difference of the voltage and the frequency, so that the non-standard driving state of the driver is evaluated.

It will be understood by those skilled in the art that the foregoing is only a preferred embodiment of the present invention, and is not intended to limit the invention, and that any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the scope of the present invention.

Claims

1. A hybrid triboelectric nano-sensor, characterized in that it has a stacked structure as a whole, and comprises, in order from top to bottom along the height direction, a first insulating encapsulation layer (10), a first ground shield layer (20), a first insulating layer (30), a first conductive element (401), a first friction layer (501), a third friction layer (60), a second friction layer (502), a second conductive element (402), a second insulating layer (30 '), a second ground shield layer (20 '), and a second insulating encapsulation layer (10 '), wherein:

The lower surface of the first friction layer (501) and the upper surface of the second friction layer (502) are used for being respectively contacted and separated with the corresponding surface of the third friction layer (60) in operation, relative sliding friction is generated, the friction area is changed, surface charge transfer on the friction layers is triggered, the surface charge transfer is conducted to the first conducting element and the second conducting element through a guiding circuit to generate a transient circuit, and an alternating current pulse electrical signal is correspondingly output to an external circuit through the conducting elements.

2. the hybrid triboelectric nanoelectrical sensor of claim 1, wherein the triboelectric series of the first, second and third friction layers are different from each other, i.e. have different degrees of attraction to charges, and the triboelectric series of the third friction layer is between the first and second friction layers.

3. a hybrid triboelectric nanoelectrical sensor according to claim 1 or 2, wherein the first and/or second friction layer preferably further comprises micro-or sub-micro-scale micro-structures distributed on the surface thereof, and wherein the micro-structures are selected from the group consisting of nanowires, nanotubes, nanoparticles, nano-grooves, micro-grooves, nano-cones, micro-cones, nano-spheres and micro-spheres.

4. A hybrid triboelectric nanoelectrical sensor according to any of claims 1 to 3, wherein the first and/or second friction layer is preferably further provided with a plurality of friction elements in a discrete array on the surface thereof, and wherein the respective friction elements of the first and second friction layers are arranged in a corresponding pattern to ensure that, in use, each friction element on the surface of the first friction layer is in partial contact with at least one friction element on the surface of the second friction layer.

5. The hybrid triboelectric nanoelectrical sensor of any of claims 1-4, wherein the first friction layer, the first conductive element, the second friction layer have a cross-section that is preferably in the shape of a semi-elliptical ring or a semi-circular ring; the cross section of the third friction layer is preferably rectangular, circular or elliptical, and the cross sections of the insulating packaging layer and the grounding shielding layer are preferably elliptical or circular.

6. a hybrid triboelectric nanogeneration sensor according to any of claims 1 to 5, wherein, when the hybrid triboelectric nanogenerator is in a non-operational state, the lower surface of the first friction layer is separated from the upper surface of the third friction layer, and the upper surface of the second friction layer is separated from the lower surface of the third friction layer; in the working state, the lower surface of the first friction layer is in contact with the upper surface of the third friction layer and generates relative friction, and the upper surface of the second friction layer is in contact with the lower surface of the third friction layer and generates relative friction.

7. The hybrid friction nanoelectrical sensor of any one of claims 1 to 6, wherein the lower surface of the first friction layer and the upper surface of the second friction layer are preferably made of an insulating material or a semiconductor material, wherein the insulating material is selected from the group consisting of aniline formaldehyde resin, polyoxymethylene, ethyl cellulose, polyamide nylon, wool and its fabric, silk and its fabric, paper, polyethylene glycol succinate, cellulose acetate, polyethylene glycol adipate, polydiallyl phthalate, regenerated cellulose sponge, cotton and its fabric, polyurethane elastomer, styrene-acrylonitrile copolymer, styrene-butadiene copolymer, wood, hard rubber, acetate, rayon, polymethylmethacrylate, polyvinyl alcohol, polyester, polyisobutylene, nylon, polyurethane elastic sponge, polyethylene terephthalate, polyvinyl butyral, butadiene-acrylonitrile copolymer, chloroprene rubber, natural rubber, polyacrylonitrile, poly (vinylidene chloride-CO-acrylonitrile), poly bisphenol a carbonate, polychlorinated ether, polyvinylidene chloride, poly (2, 6-dimethyl polyphenylene oxide), polystyrene, polyethylene, polypropylene, poly diphenylpropane carbonate, polyethylene terephthalate, polyimide, polyvinyl chloride, polydimethylsiloxane, polychlorotrifluoroethylene, polytetrafluoroethylene, or parylene; and the semiconductor material is selected from the following undoped materials: silicon, germanium, group III and V compounds, group II and VI compounds, solid solutions consisting of group III-V compounds and group II-VI compounds, amorphous glass semiconductors and organic semiconductors, wherein the group III and V compounds are selected from gallium arsenide and gallium phosphide; the group II and VI compounds are selected from the group consisting of thiofides and zinc sulfides; the solid solution consisting of group III-V compounds and group II-VI compounds is selected from gallium aluminum arsenic and gallium arsenic phosphorus.

8. The hybrid triboelectric nanoelectrical sensor of any of claims 1-6, wherein the material of the lower surface of the first friction layer and the upper surface of the second friction layer is preferably selected from non-conductive oxides, semiconductor oxides, or complex oxides, including silicon oxide, aluminum oxide, manganese oxide, chromium oxide, iron oxide, copper oxide, zinc oxide, BiO₂And Y₂O₃。

9. The hybrid triboelectric nanoelectrical sensor of claim 7 or 8, wherein the third friction layer is made of a conductive material, and the conductive material is preferably selected from indium tin oxide, graphene, silver nanowire films, metals, alloys, conductive oxides, or conductive polymers; wherein the metal is gold, silver, platinum, palladium, aluminum, nickel, copper, titanium, chromium, tin, iron, manganese, molybdenum, tungsten or vanadium; the alloy is an aluminum alloy, a titanium alloy, a magnesium alloy, a beryllium alloy, a copper alloy, a zinc alloy, a manganese alloy, a nickel alloy, a lead alloy, a tin alloy, a cadmium alloy, a bismuth alloy, an indium alloy, a gallium alloy, a tungsten alloy, a molybdenum alloy, a niobium alloy, or a tantalum alloy.

10. The hybrid friction nano-power generation sensor according to claim 7 or 8, wherein the lower surface of the first friction layer and the lower surface of the third friction layer are preferably friction electrode sequence materials with negative polarity, selected from polystyrene, polyethylene, polypropylene, poly diphenyl propane carbonate, polyethylene terephthalate, polyimide, polyvinyl chloride, polydimethylsiloxane, polychlorotrifluoroethylene, polytetrafluoroethylene and parylene; correspondingly, the upper surfaces of the second friction layer and the third friction layer are preferably positive friction electrode sequence materials selected from aniline formaldehyde resin, polyformaldehyde, ethyl cellulose, polyamide nylon, wool and fabrics thereof, silk and fabrics thereof, paper, polyethylene glycol succinate, cellulose acetate, polyethylene glycol adipate, polydiallyl phthalate, regenerated cellulose sponge, cotton and fabrics thereof, polyurethane elastomer, styrene-acrylonitrile copolymer, styrene-butadiene copolymer, wood, hard rubber, acetate, rayon, polymethyl methacrylate, polyvinyl alcohol, polyester, copper, aluminum, gold, silver, steel and silicon.