CN105702283A - Triboelectrification-based movement locus memory device and method - Google Patents

Abstract

The invention discloses a motion track memory device and method based on friction electrification. The device comprises a friction layer (1) made of dielectric material, a ferroelectric layer (2), an electrode layer (3) and a moving object (4), and the ferroelectric layer (2) is arranged between the friction layer (1) and the electrode layer ( 3) Between. The moving object (4) electrically connected to the electrode layer (3) and the friction layer (1) can move relatively, and the two generate opposite charges respectively, and the charges on the moving object (4) are conducted to the electrode layer (4) . The polarization electric field generated by the charge on the friction layer (1) and the charge on the electrode layer (3) changes the polarization direction of the electric dipole in the ferroelectric layer (2), and this change in the polarization direction acts as a response to the motion The memory of object (4) trajectory. The invention has simple structure, high sensitivity and reliability, and can directly convert mechanical motion into storable logic electrical signals without external power supply, so as to realize self-driven memory storage.

Description

Motion track memory device and memory method based on friction electrification

technical field

The invention relates to the technical field of motion track memory and sensing, in particular to a motion track memory device and memory method based on the combination of triboelectric effect and ferroelectric material.

Background technique

In recent years, scientists from all over the world are actively developing various new environmentally friendly power generation methods in order to solve environmental pollution problems and reduce power generation costs. Since 2012, the inventors of this invention have been trying to use common phenomena such as triboelectricity and static electricity to collect and utilize the electric energy generated by people’s every move, and then developed a series of triboelectric generators.

On the other hand, using the spontaneous polarization properties of ferroelectric materials to realize the memory storage of electronic signals is also a promising direction. Especially considering that organic polymer ferroelectric materials have the characteristics of flexible preparation process and soft texture, they can have great potential applications in the field of flexible electronics. If a self-powered power generation device based on frictional electrification can be combined with it, the memory of the motion trajectory can be realized while saving energy.

Contents of the invention

(1) Technical problems to be solved

The purpose of the present invention is to provide a memory device and memory method that utilizes the combination of triboelectricity and ferroelectric effect, so as to realize the integration of triboelectric generation and displacement sensor, and realize the memory and storage of the moving track of moving objects.

(2) Technical solution

In order to solve the above problems, the present invention proposes a motion trajectory memory device based on triboelectricity, which includes a friction layer, a ferroelectric layer, an electrode layer and a moving object, wherein the friction layer is made of a dielectric material, which is compatible with The moving object can move relative to each other, thereby generating opposite charges on the friction layer and the moving object; the moving object is electrically connected to the electrode layer, thus, the moving object The charge on the friction layer can be conducted to the electrode layer; the ferroelectric layer is located between the friction layer and the electrode layer, and is made of a ferroelectric material, and the charge on the friction layer is connected to the electrode layer. The polarization electric field generated by the charges can change the polarization direction of the electric dipoles in the ferroelectric layer.

According to an embodiment of the present invention, the spontaneous polarization direction of the ferroelectric layer is opposite to the polarization electric field.

According to an embodiment of the present invention, the friction layer is a flexible dielectric material; the ferroelectric layer is a flexible ferroelectric material.

According to one embodiment of the present invention, the material of the friction layer is polyester resin, polytetrafluoroethylene, fluorinated ethylene propylene copolymer, or polyimide; the material of the ferroelectric layer is polyvinylidene fluoride and its derivatives.

According to an embodiment of the present invention, the ferroelectric material of the ferroelectric layer satisfies E _C <σ/ε, wherein E _C is the coercive electric field strength of the ferroelectric material, and σ is the electric charge that generates the polarization electric field Density, ε is the dielectric constant of the ferroelectric material.

According to an embodiment of the present invention, the ferroelectric layer and the friction layer are thin films attached to each other, and the two are insulated from each other.

According to an embodiment of the present invention, the ferroelectric layer and the friction layer both have a thickness of 1-100 μm.

According to an embodiment of the present invention, the relative motion between the friction layer and the moving object is a sliding friction motion along the contact surface of the two.

According to an embodiment of the present invention, the moving object slides along a movement track on the surface of the friction layer after moving from a position not in contact with the friction layer to contact with the friction layer, and then moves again to a position not in contact with the friction layer. Where the friction layer contacts, a polarization direction of an electric dipole of the ferroelectric layer located in a region corresponding to the track is changed by the polarization electric field.

According to an embodiment of the present invention, the moving object moves from a position away from the friction layer to contact with the friction layer, and then moves away from the friction layer from the contact position, and the ferroelectric layer is located in the same position as the friction layer. The polarization direction of the electric dipole in the region corresponding to the contact position is changed by the polarization electric field.

According to an embodiment of the present invention, the electrode layer and the ferroelectric layer are attached to each other but insulated.

According to an embodiment of the present invention, the whole of the moving object is a conductor; or, part of the moving object is a conductor and part is an insulator, and the conductive part of the moving object is electrically connected to the electrode layer.

The present invention also proposes a motion track memory method based on triboelectricity, which includes the following steps: a ferroelectric layer is arranged between a friction layer and an electrode layer, the friction layer is made of a dielectric material, the ferroelectric layer Composed of ferroelectric materials; make a moving object electrically connected to the electrode layer move relative to the friction layer so as to generate opposite charges on the friction layer and the moving object respectively, and the movement The charge on the object is conducted to the electrode layer; the polarization electric field generated by the charge on the friction layer and the charge on the electrode layer changes the polarization direction of the electric dipole in the ferroelectric layer.

According to an embodiment of the present invention, the spontaneous polarization direction of the ferroelectric layer is opposite to the polarization electric field.

According to an embodiment of the present invention, the friction layer is a flexible dielectric material; the ferroelectric layer is a flexible ferroelectric material.

According to one embodiment of the present invention, the material of the friction layer is polyester resin, polytetrafluoroethylene, fluorinated ethylene propylene copolymer, or polyimide; the material of the ferroelectric layer is polyvinylidene fluoride and its derivatives.

According to an embodiment of the present invention, the ferroelectric material of the ferroelectric layer satisfies E _C <σ/ε, wherein E _C is the coercive electric field strength of the ferroelectric material, and σ is the electric charge that generates the polarization electric field Density, ε is the dielectric constant of the ferroelectric material.

According to one embodiment of the present invention, the ferroelectric layer and the friction layer are made into thin films and attached to each other, and they are insulated from each other.

According to an embodiment of the present invention, the ferroelectric layer and the friction layer both have a thickness of 1-100 μm.

According to an embodiment of the present invention, the relative motion between the friction layer and the moving object is a sliding friction motion along the contact surface of the two.

According to one embodiment of the present invention, the moving object is moved from a position not in contact with the friction layer to being in contact with the friction layer and slides along a movement track on the surface of the friction layer, and then moves to a non-contact position again. At a position in contact with the friction layer, a polarization direction of an electric dipole located in a region of the ferroelectric layer corresponding to the track is changed by the polarization electric field.

According to an embodiment of the present invention, the moving object is moved from a position away from the friction layer to contact with the friction layer, and then moves away from the friction layer from the contact position, and the ferroelectric layer is located in contact with the friction layer. The polarization direction of the electric dipole in the region corresponding to the contact position is changed by the polarization electric field.

According to an embodiment of the present invention, the electrode layer and the ferroelectric layer are attached to each other but insulated.

According to one embodiment of the present invention, the moving object is a conductor as a whole; or, the moving object is partly a conductor and partly an insulator, and the conductive part of the moving object is electrically connected to the electrode layer and is insulated. The part moves relative to the friction layer.

(3) Beneficial effects

The present invention is simple in structure, low in cost, and has high sensitivity. At the same time, the logic signal memorized and stored in the present invention has good stability and reliability, and can directly convert mechanical motion into a storable Logical electrical signals to realize self-driven memory storage.

Description of drawings

Fig. 1 is a schematic structural view of a motion trajectory memory device based on friction electrification of the present invention;

Fig. 2 is a schematic diagram of a working mode of the motion trajectory memory device based on friction electrification of the present invention;

Fig. 3 is a schematic diagram of another working mode of the motion trajectory memory device based on friction electrification of the present invention;

Fig. 4 is a schematic structural view of a motion trajectory memory device according to an embodiment of the present invention;

Fig. 5 is a schematic structural diagram of a movement track memory device according to another embodiment of the present invention.

detailed description

Fig. 1 is a schematic structural diagram of a motion trajectory memory device based on triboelectric electrification according to the present invention. As shown in FIG. 1 , the memory device includes a friction layer 1 , a ferroelectric layer 2 , an electrode layer 3 and a moving object 4 . The friction layer 1 and the moving object 4 can move relative to each other, so that opposite charges are generated on the friction layer 1 and the moving object 4 respectively. The moving object 4 is electrically connected to the electrode layer 3 , for example, through a wire 5 , so that the charge on the moving object 4 can be conducted to the electrode layer 4 .

The material of the friction layer 1 is a dielectric material, which may be a flexible dielectric material, preferably polyester resin, polytetrafluoroethylene, fluorinated ethylene propylene copolymer, or polyimide (PI) film material and the like. In addition, in order to ensure the triboelectrification effect between the moving object 4 and the friction layer 1, the materials of the contactable parts of the moving object 4 and the friction layer 1 should have different triboelectric sequences.

The moving object 4 can be a conductor as a whole, or a part of it can be a conductor, and a part can be an insulator. The conductive part of the moving object is connected to the electrode layer 3 through a wire 5 . When the insulating part of the moving object 4 and the friction layer 1 are in contact with each other, the materials of the insulating part and the friction layer are different.

The ferroelectric layer 2 is located between the friction layer 1 and the electrode layer 3 and is made of a ferroelectric material, which may be a flexible ferroelectric material, preferably a polymer, such as polyvinylidene fluoride and its related derivatives. Ferroelectric materials have spontaneous electric polarity because their crystal structure determines the formation of many electric dipoles inside them. In FIG. 1 , reference numeral 21 represents the electric dipole inside it, and the direction of the arrow indicates the polarization direction of the electric dipole, and this FIG. 1 shows that the spontaneous polarization direction is vertically upward. However, those skilled in the art should understand that the electric dipole 21 in FIG. 1 is only a schematic representation. However, from a macroscopic point of view, it may appear as a consistent polarization direction.

Fig. 2 is a principle diagram of a working mode of the frictional electrification-based motion trajectory memory device of the present invention. As shown in FIG. 2 , the relative motion between the friction layer 1 and the moving object 4 is a sliding friction motion along the contact surfaces of the two.

Specifically, the moving object 4 moves from a position not in contact with the friction layer 1 (left figure) to sliding along a movement track on the surface of the friction layer 1 after contacting the friction layer 1 (middle figure), and moves again to a position where it does not come into contact with the friction layer 1 (pictured right). According to the principle of triboelectricity generation, charges of one polarity (such as positive charges) are generated on the lower surface of the moving object 1 , and charges of another polarity (such as negative charges) are accumulated on the upper surface of the friction layer 1 . Since the friction layer 1 is made of a dielectric material, the charges formed on its surface will not migrate and disappear as the moving object 4 moves away. Therefore, in order to balance the electric field, the charge on the lower surface of the moving object 1 will be transferred to the electrode layer 3 at the bottom of the ferroelectric layer 2 along with the electrical connection line (i.e., the wire 5), and form an electric charge on the upper surface of the friction layer 1. In the vertical correspondence, the friction layer 1 will form a charge accumulation area at the moving track of the moving object 4, and in this area, an electric field will be formed along the thickness direction of the ferroelectric layer 2, which is called a polarization electric field here. This polarization electric field E will polarize the electric dipole inside the ferroelectric layer 2, and when the polarization electric field is large enough, the electric dipole in the region corresponding to the track of the ferroelectric layer 2 will The polarization direction of the poles is changed by the polarization electric field, so the polarization can be used as a kind of memory and storage for the moving track of the sliding object.

According to the law of electric field distribution inside the basic dielectric material, in order to ensure that the ferroelectric layer 2 is reversely polarized, the ferroelectric material of the ferroelectric layer 2 should satisfy E _C <σ/ε, where E _C is the ferroelectric The coercive electric field strength of the material, σ is the charge density generating the polarizing electric field, and ε is the dielectric constant of the ferroelectric material.

Preferably, the spontaneous polarization direction of the ferroelectric layer 2 is opposite to the polarization electric field, so that when a polarization electric field is generated, the polarization electric field causes the polarization direction of the ferroelectric layer 2 to be reversed.

Preferably, both the ferroelectric layer 2 and the friction layer 1 are thin films with a thickness in the range of 1-100 μm. Since the friction layer 1 is a dielectric material, the two are usually insulated, so they can be attached to each other. Preferably, the total thickness of the friction layer 1 and the ferroelectric layer 2 is much smaller than the moving distance of the moving object 4, so as to implement actual track memory and sensing applications.

Although the electrode layer is usually a conductive metal or alloy material, the material of the ferroelectric layer 2 can be selected as a material with a large dielectric constant, such as polyvinylidene fluoride and its derivatives, such as P(VDF-TrFE) And so on, at the same time, this type of ferroelectric material has high resistance, therefore, the electrode layer 3 and the ferroelectric layer 2 can be insulated from each other, and they can be attached to each other. The thickness of the electrode layer is generally several hundred nanometers or one or two micrometers, and the present invention is not limited to a specific thickness.

When the friction layer 1, the ferroelectric layer 2 and the electrode layer 3 are all bonded together, a tightly bonded device can be obtained, which is convenient for further application of track recording.

Fig. 3 is a schematic diagram of another working mode of the motion trajectory memory device based on friction electrification of the present invention. As shown in FIG. 3 , the difference between this working mode and that shown in FIG. 2 is that the moving object 4 adopts a motion mode of “away→contact→away” relative to the friction layer. That is, first, the moving object 4 moves from a position away from the friction layer 1 to contact with the friction layer 1 , and then moves away from the friction layer 1 from the contact position. Its working principle is similar to that shown in Figure 2, except that when the moving object 4 moves upwards from the contact position (middle figure), the upper surface of the friction layer 1 retains charges only at the contact position. In this way, the polarization direction of the electric dipole located in the region corresponding to the contact position of the ferroelectric layer 2 can be changed by the polarization electric field. In this way, the motion of the moving animal can be memorized and stored in point form.

Both of the above two working methods can memorize the moving track (linear or point shape) of the moving object. When reading the motion track, it can be read by measuring the change of the polarization direction of the ferroelectric layer. For example, the film surface (lower surface) of the ferroelectric layer 2 can be scanned by scanning probe microscope or KavinProbe technology, and the polarization density (surface charge density) at different positions can be distinguished. The charge density will be greatly increased, and the trajectory of the object can be resolved. Of course, it is also possible to use a simpler displacement current side measurement method to install additional electrodes on the upper and lower surfaces of the friction layer 1 and the ferroelectric layer 2 to measure the ferroelectric layer 2. By observing the change of the current peak value, the extreme Density analysis.

In order to make the object, technical solution and advantages of the present invention clearer, the present invention will be further described in detail below in conjunction with specific examples.

Fig. 4 is a schematic structural diagram of a motion trajectory memory device according to an embodiment of the present invention. As shown in FIG. 4 , the device of this embodiment includes a friction layer 1 , a ferroelectric layer 2 and an electrode layer 3 laminated in sequence. The three are laminated to form a square thin film device. The material of the friction layer 1 is polyester resin, polytetrafluoroethylene, fluorinated ethylene propylene copolymer, or polyimide film material, etc., on one surface of the friction layer 1 (it is the lower surface in FIG. 4 ), A layer of thin film material as the ferroelectric layer 2, which is polyvinyl fluoride in this embodiment, is attached by means of glue spinning, vapor deposition or direct bonding.

The initial polarization direction of the ferroelectric layer 2 film is opposite to the direction of the electric field generated by friction, so that the polarization electric field generated after triboelectrification can reversely polarize the ferroelectric layer 2 film. That is to say, the initial polarization direction of the ferroelectric layer 2 is a bottom-up vertical direction.

The thickness of the friction layer 1 is several microns to tens of microns, and the thickness of the ferroelectric layer 2 is also several microns to tens of microns. On the other surface (lower surface) of the ferroelectric layer 2, a conductive layer (preferably metal) is attached as the electrode layer 3 by evaporation, magnetron sputtering or chemical deposition, and its thickness is about 300 nanometers.

The electrode layer 3 is connected to a moving object 4 via wires. The moving object 4 is here a cylinder made of conductive (preferably metal) material with an outer diameter of 1 cm and a thickness of 0.5 cm. (In other embodiments, other suitable sizes can also be selected as required, as long as the size of the moving object 4 is guaranteed to be far smaller than the plane size where its motion track is located) The moving object 4 can slide on the upper surface of the friction layer 1, It is also possible to move up and down and contact the upper surface of the friction layer 1 . Regardless of the movement mode, the polarization direction at the position perpendicular to the movement track (including the point contact position) of the ferroelectric layer 2 is reversed, thereby achieving the purpose of memorizing the movement track.

Fig. 5 is a schematic structural diagram of a movement track memory device according to another embodiment of the present invention. As shown in Figure 5, the difference between this embodiment and the embodiment of Figure 4 is that the moving object of this embodiment is a flat plate structure, and it is attached to the friction layer 1, the ferroelectric layer 2 and the electrode layer 3 The area of the square thin-film device formed later is equivalent, and its size and shape are the same as those of the friction layer 1 . In the initial state, the moving object 4 is completely overlapped with the friction layer 1 . During the working process, the moving object 4 slides sideways along a side of the square friction layer 1 (as shown in the arrow direction in Figure 5), and the sliding distance is S, thus, in the direction of motion of the moving object 4 The opposite side forms a dislocation area with the friction layer S, and the length of this area along the moving direction is also S, as shown in Fig. 5 .

According to the above working principle, the movement track at this time is a surface track, that is, at the position where the dislocation region is located. In this way, the polarization direction of the corresponding vertical position of the ferroelectric layer corresponding to the dislocation region is reversed. By measuring the change of the polarization direction, the moving distance S of the moving object 4 to one side can also be obtained.

The specific embodiments described above have further described the purpose, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above descriptions are only specific embodiments of the present invention, and are not intended to limit the present invention. Within the spirit and principles of the present invention, any modifications, equivalent replacements, improvements, etc., shall be included in the protection scope of the present invention.

Claims (24)

1. the movement locus memory based on triboelectrification, it is characterised in that include frictional layer (1), ferroelectric layer (2), electrode layer (3) and moving object (4), wherein,

Described frictional layer (1) is made up of dielectric material, and relative motion can occur for itself and described moving object (4), thus producing character opposite charge respectively on described frictional layer (1) and described moving object (4)；

Being electrically connected between described moving object (4) and described electrode layer (4), thus, the electric charge on described moving object (4) can be conducted to described electrode layer (4)；

Described ferroelectric layer (2) is positioned between described frictional layer (1) and described electrode layer (3), being made up of ferroelectric material, the electric charge on described frictional layer (1) and polarized electric field produced by the electric charge on described electrode layer (3) can change the polarised direction of electric dipole in described ferroelectric layer (2)。

2. the movement locus memory based on triboelectrification as claimed in claim 1, it is characterised in that the spontaneous polarization direction of described ferroelectric layer (2) is contrary with described polarized electric field。

3. the movement locus memory based on triboelectrification as claimed in claim 1, it is characterised in that described frictional layer (1) is flexible dielectric；Described ferroelectric layer (2) is flexible ferroelectric material。

4. the movement locus memory based on triboelectrification as claimed in claim 1, it is characterised in that the material of described frictional layer (1) is polyester resin, politef, fluorinated ethylene propylene copolymer, or polyimides；

The material of described ferroelectric layer (2) is Kynoar and derivant thereof。

5. the movement locus memory based on triboelectrification as claimed in claim 1, it is characterised in that the ferroelectric material of described ferroelectric layer (2) meets E_C< σ/ε, wherein E_CFor the coercive field strength of this ferroelectric material, σ is the charge density producing described polarized electric field, and ε is the dielectric constant of this ferroelectric material。

6. the movement locus memory based on triboelectrification as claimed in claim 1, it is characterised in that described ferroelectric layer (2) and described frictional layer (1) are thin film bonded to each other, and the two mutually insulated。

7. the movement locus memory based on triboelectrification as claimed in claim 6, it is characterised in that the thickness of described ferroelectric layer (2) and described frictional layer (1) is 1～100 μm。

8. the movement locus memory based on triboelectrification as claimed in claim 1, it is characterised in that the relative motion between described frictional layer (1) and described moving object (4) is the sliding friction campaign of the contact surface along the two。

9. the movement locus memory based on triboelectrification as claimed in claim 6; it is characterized in that; described moving object (4) slides along a movement locus on the surface of this frictional layer (1) from moving with described frictional layer (1) discontiguous position after contacting with described frictional layer (1); and it being moved again to the position not contacted with described frictional layer (1), the polarised direction of the electric dipole being positioned at the region corresponding with described track of described ferroelectric layer (2) is changed by described polarized electric field。

10. the movement locus memory based on triboelectrification as claimed in claim 1, it is characterized in that, described moving object (4) moves from the position away from described frictional layer (1) and contacts to described frictional layer (1), and from contact position away from described frictional layer (1), the polarised direction of the electric dipole being positioned at the region corresponding with described contact position of described ferroelectric layer (2) is changed by described polarized electric field。

11. the movement locus memory based on triboelectrification as claimed in claim 1, it is characterised in that described electrode layer (3) is bonded to each other with described ferroelectric layer (1) but insulate。

12. the movement locus memory based on triboelectrification as claimed in claim 1, it is characterised in that described moving object (4) generally conductor；

Or, described moving object (4) part is conductor, and part is insulator, is electrically connected between conductor part and the described electrode layer (4) of described moving object (4)。

13. the movement locus accumulating method based on triboelectrification, it is characterised in that comprise the steps:

One ferroelectric layer (2) being arranged between a frictional layer (1) and an electrode layer (3), this frictional layer (1) is made up of dielectric material, and this ferroelectric layer (2) is made up of ferroelectric material；

Make a moving object (4) being electrically connected with described electrode layer (3), with described frictional layer (1), relative motion occur, to produce character opposite charge on described frictional layer (1) and described moving object (4) respectively, and the electric charge on this moving object (4) is conducted to described electrode layer (4)；

Electric charge on described frictional layer (1) and polarized electric field produced by the electric charge on described electrode layer (3) change the polarised direction of electric dipole in described ferroelectric layer (2)。

14. the movement locus accumulating method based on triboelectrification as claimed in claim 13, it is characterised in that the spontaneous polarization direction making described ferroelectric layer (2) is contrary with described polarized electric field。

15. the movement locus accumulating method based on triboelectrification as claimed in claim 13, it is characterised in that described frictional layer (1) is flexible dielectric；Described ferroelectric layer (2) is flexible ferroelectric material。

16. the movement locus accumulating method based on triboelectrification as claimed in claim 13, it is characterised in that the material of described frictional layer (1) is polyester resin, politef, fluorinated ethylene propylene copolymer, or polyimides；

The material of described ferroelectric layer (2) is Kynoar and derivant thereof。

17. the movement locus accumulating method based on triboelectrification as claimed in claim 13, it is characterised in that the ferroelectric material of described ferroelectric layer (2) meets E_C< σ/ε, wherein E_CFor the coercive field strength of this ferroelectric material, σ is the charge density producing described polarized electric field, and ε is the dielectric constant of this ferroelectric material。

18. the movement locus accumulating method based on triboelectrification as claimed in claim 13, it is characterised in that described ferroelectric layer (2) and described frictional layer (1) are made thin film and bonded to each other, and the two mutually insulated。

19. the movement locus accumulating method based on triboelectrification as claimed in claim 18, it is characterised in that the thickness of described ferroelectric layer (2) and described frictional layer (1) is 1～100 μm。

20. the movement locus accumulating method based on triboelectrification as claimed in claim 13, it is characterised in that making the relative motion between described frictional layer (1) and described moving object (4) is the sliding friction campaign of the contact surface along the two。

21. the movement locus accumulating method based on triboelectrification as claimed in claim 20; it is characterized in that; described moving object (4) is made to slide along a movement locus on the surface of this frictional layer (1) after contacting with described frictional layer (1) from moving with described frictional layer (1) discontiguous position; and it being moved again to the position not contacted with described frictional layer (1), the polarised direction of the electric dipole being positioned at the region corresponding with described track of described ferroelectric layer (2) is changed by described polarized electric field。

22. the movement locus accumulating method based on triboelectrification as claimed in claim 20, it is characterized in that, make described moving object (4) move from the position away from described frictional layer (1) to contact to described frictional layer (1), and from contact position away from described frictional layer (1), the polarised direction of the electric dipole being positioned at the region corresponding with described contact position of described ferroelectric layer (2) is changed by described polarized electric field。

23. the movement locus accumulating method based on triboelectrification as claimed in claim 13, it is characterised in that make described electrode layer (3) and described ferroelectric layer (1) bonded to each other but insulation。

24. the movement locus accumulating method based on triboelectrification as claimed in claim 13, it is characterised in that described moving object (4) generally conductor；

Or, described moving object (4) part is conductor, part is insulator, is electrically connected between conductor part and the described electrode layer (4) of described moving object (4), and insulated part, with described frictional layer (1), relative motion occurs。