Friction electricity yarn, preparation method thereof and friction nanometer power generation device

Abstract

The invention relates to the field of friction nano-generators, in particular to a friction electric yarn, a preparation method thereof and a friction nano-generator. The triboelectric yarn comprises a conductive core wire and a friction layer wrapping the outer layer of the conductive core wire, the friction layer comprises a plurality of friction fibers arranged in an oriented mode, the friction fibers are mutually adhered to form a doubling structure, the main component of the friction fibers is a triboelectric polymer material, and triboelectric polymers have dielectric properties and spinnability. The triboelectric yarn is synchronously sprayed towards the conductive core wire through the same spinning solution by an injector to which voltages in different directions are applied, electrostatic spinning is carried out, and therefore the oriented doubling structure is formed. The friction nanometer power generation device with the friction electricity yarn as the positive friction layer and / or the negative friction layer has high output efficiency, stability and sensitivity.

Description

Technical Field

[0001] The present invention relates to the field of triboelectric nanogenerators, and in particular to a triboelectric yarn, a preparation method thereof, and a triboelectric nanogenerator device. Background Art

[0002] A triboelectric nanogenerator (TENG) is a micro-power generation device that converts mechanical energy into electrical energy through the triboelectrostatic effect. Its core principle is based on the coupling of charge migration generated by the contact and separation of materials with electrostatic induction. It can harvest a variety of weak mechanical energies, such as human movement, breathing, and friction, and has been widely used in fields such as the Internet of Things (IoT), smart wearables, and biomedical monitoring. A TENG consists of three core components: a friction layer, a substrate, and electrodes. The friction layer, as the core region of energy conversion, generates charge through the contact and separation of two different dielectric materials. In recent years, triboelectric yarns have become an important research area for the friction layer of "wearable" TENGs due to their inherent flexibility, weavability, and adaptability to fabric integration.

[0003] Existing triboelectric yarns are mostly "core-shell" structures, consisting of a conductive fiber core layer coated with a triboelectric polymer material to form a friction layer. However, the charge output efficiency of such triboelectric yarns is low and unstable, making them difficult to apply in scenarios such as intelligent sensing. Summary of the Invention

[0004] The object of the present invention is to provide a triboelectric yarn with high charge output efficiency and stability, a preparation method thereof, and a triboelectric nano-power generation device.

[0005] In order to achieve the above object, the present invention provides the following technical solutions: A triboelectric yarn comprises a conductive core wire and a friction layer wrapped around the outer layer of the conductive core wire. The friction layer comprises a plurality of oriented friction fibers, and the plurality of friction fibers are adhered to each other to form a parallel yarn structure. The main component of the friction fibers is a triboelectric polymer material, and the triboelectric polymer has dielectric properties and spinnability.

[0006] Optionally, the triboelectric polymer material includes any one of polyvinylidene fluoride, polytetrafluoroethylene, polyurethane, polyacrylonitrile, polyimide, polylactic acid and chitosan.

[0007] Optionally, the conductive core wire is a flexible yarn whose surface is covered with a conductive layer.

[0008] Optionally, the flexible yarn is made of nylon, and the conductive layer is made of elemental silver.

[0009] The present invention also provides a method for preparing the above-mentioned triboelectric yarn, comprising: dissolving the triboelectric polymer material in a matching spinning solvent to obtain a spinning solution; The spinning solution is added into two syringes respectively, and the conductive core wire is passed through a metal funnel, so that the two syringes with opposite voltages are simultaneously sprayed toward the conductive core wire for electrostatic spinning to form the friction layer covering the conductive core wire, thereby obtaining the friction electric yarn.

[0010] Optionally, the viscosity of the spinning solution is any value between 2652 mPa·s and 5364 mPa·s.

[0011] Optionally, the triboelectric polymer material is polyvinylidene fluoride.

[0012] Optionally, the spinning solvent is a mixture of N,N-dimethylformamide and acetone, and the mass ratio of the N,N-dimethylformamide to the acetone is any value between (1.3~1.7):1, and the concentration of the triboelectric polymer material in the spinning solution is any value between 14wt% and 18wt%.

[0013] Optionally, the inner diameter of the needle of the syringe is any value between 0.5 mm and 0.8 mm, the extrusion speed of the spinning solution in the electrospinning is any value between 0.8 mL / h and 1.2 mL / h, the collection speed of the friction electric yarn is any value between 0.4 cm / s and 0.6 cm / s, the rotation speed of the metal funnel is any value between 200 rpm and 400 rpm, and the spinning voltage of the electrospinning is any value between ±5.5 kV and ±7 kV.

[0014] The present invention also provides a friction nano-power generation device, comprising a positive friction layer, a negative friction layer, an insulating substrate, an elastic support and an external circuit, wherein the positive friction layer and / or the negative friction layer comprise the above-mentioned friction electric yarn, the positive friction layer and the negative friction layer are respectively carried on two insulating substrates and arranged opposite to each other, and both insulating substrates are carried on the elastic support, so that the positive friction layer and the negative friction layer can be controllably contacted or separated, when the positive friction layer contacts the negative friction layer, electrons are transferred unidirectionally from the positive friction layer to the negative friction layer, so that the positive friction layer and the negative friction layer form an electric potential difference when they are separated, and the external circuit is electrically connected to the positive friction layer and / or the negative friction layer for collecting current.

[0015] The beneficial effects of the present invention are as follows: the oriented parallel fiber structure transforms the contact mode from line contact of a single fiber to double-point contact, thereby improving the contact stability. Compared with the single fiber structure, the oriented parallel fiber structure generally also has a higher inter-fiber porosity, which further improves the output performance. In addition, at the interface of two parallel fibers, the application of a reverse high voltage will lead to differences in molecular chain orientation and residual stress, forming energy barriers and deep traps, which can effectively capture transferred charges and reduce leakage current, thereby simultaneously improving output performance and stability. In addition, the introduction of an ordered oriented parallel fiber structure can improve the arrangement and contact efficiency of nanofibers, promote charge capture and retention, reduce charge loss and other mechanisms, and ultimately achieve a comprehensive improvement in triboelectric performance.

[0016] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention and implement it according to the contents of the specification, the following is a detailed description of the preferred embodiments of the present invention with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a flow chart of the method for preparing the triboelectric yarn shown in Example 1 of the present invention; Figure 2 This is a cross-sectional electron microscope image and a partial magnified image of the triboelectric yarn shown in Example 1 of the present invention; Figure 3 Schematic diagram of the structure of the triboelectric nano-power generation device shown in Example 1 of the present invention; Figure 4 Schematic diagram of the power generation principle of the triboelectric nano-power generation device shown in Example 1 of the present invention; Figure 5 A linear diagram showing the open circuit voltage and pressure fitting of the triboelectric nano-power generation device shown in Example 1 of the present invention; Figure 6 This is a diagram showing glove finger flexion detection of the triboelectric nano-power generation device shown in Example 1 of the present invention; Figure 7 This is a stability test diagram of the triboelectric nano-power generation device shown in Example 1 of the present invention; Figure 8 Surface electron micrographs of the triboelectric yarns shown in Example 1 and Example 2 of the present invention; Figure 9 Graphs showing open circuit voltage detection of the triboelectric yarns shown in Example 1 and Example 2 of the present invention; Figure 10 Surface electron micrographs of the triboelectric yarns shown in Example 1 and Example 3 of the present invention; Figure 11 Figure 2 is a diagram of a fiber cone formed on the metal funnel during spinning in Example 1 and Example 4 of the present invention; Figure 12Surface electron microscope images of the triboelectric yarns shown in Example 1 and Example 4 of the present invention.

[0018] Legend: 1-positive friction layer, 2-negative friction component, 21-friction electric yarn, 22-insulating wire frame, 23-negative friction layer, 3-insulating base, 4-elastic bracket, 41-first load-bearing part, 42-second load-bearing part, 43-first elastic part, 44-second elastic part. DETAILED DESCRIPTION

[0019] The technical solution of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0020] In the description of the present invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings and are intended solely to facilitate and simplify the description of the present invention. They are not intended to indicate or imply that the devices or components referred to must have, be constructed, or operate in a specific orientation, and therefore should not be construed as limitations on the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0021] In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they may refer to fixed, detachable, or integral connections; mechanical or electrical connections; direct or indirect connections through an intermediate medium; and internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on the specific circumstances.

[0022] In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0023] The present invention applies to protect a triboelectric yarn, which includes a conductive core wire and a friction layer wrapped around the outer layer of the conductive core wire. The friction layer includes a plurality of oriented friction fibers, and the plurality of friction fibers are adhered to each other to form a parallel yarn structure. The main component of the friction fibers is a triboelectric polymer material, and the triboelectric polymer has dielectric properties and spinnability.

[0024] The oriented parallel-filament structure transforms the contact mode from line contact of a single fiber to double-point contact, thereby improving contact stability. Compared with the single-fiber structure, the oriented parallel-filament structure generally has a higher inter-fiber porosity, which further improves the output performance. In addition, at the interface of two parallel fibers, the application of a reverse high voltage will lead to differences in molecular chain orientation and residual stress, forming energy barriers and deep traps, which can effectively capture transferred charges and reduce leakage current, thereby simultaneously improving output performance and stability. In addition, the introduction of an ordered oriented parallel-filament structure can improve the arrangement and contact efficiency of nanofibers, promote charge capture and retention, reduce charge loss and other mechanisms, and suppress the interface polarity chaos caused by the disordered arrangement of friction fibers, ultimately achieving a comprehensive improvement in triboelectric performance.

[0025] In some embodiments, the triboelectric polymer material includes any one of polyvinylidene fluoride, polytetrafluoroethylene, polyurethane, polyacrylonitrile, polyimide, polylactic acid, and chitosan.

[0026] In some embodiments, the conductive core is a flexible yarn with a conductive layer covering its surface.

[0027] In some embodiments, the flexible yarn is made of nylon, and the conductive layer is made of elemental silver.

[0028] The present invention also claims a method for preparing the triboelectric yarn, comprising: S1. Dissolving the triboelectric polymer material in a prepared spinning solvent to obtain a spinning solution.

[0029] S2. Add the spinning solution into two syringes respectively, and pass the conductive core wire through the metal funnel, so that the two syringes with opposite voltages are simultaneously sprayed toward the conductive core wire for electrostatic spinning to form a friction layer covering the conductive core wire to obtain triboelectric yarn.

[0030] By applying opposite voltages to the syringes and performing electrospinning simultaneously, the jets of spinning solution ejected from the two syringes carry opposite charges in the electric field and attract and entwine with each other. This dynamic balance causes the friction fibers to align in the direction of the electric field, forming a continuous bundle structure or a parallel composite structure. Because the spinning solution forming the oppositely charged jets has the same composition and a certain viscosity, the friction fibers adhere to each other in pairs, forming an oriented parallel yarn structure.

[0031] In some embodiments, the viscosity of the spinning solution is any value between 2652 mPa·s and 5364 mPa·s, for example, any value between 2652 mPa·s, 3000 mPa·s, 4000 mPa·s, 5000 mPa·s, and 5364 mPa·s. When the viscosity of the spinning solution is too low, the jet will exhibit significant instability, specifically manifested as severe jet splitting and rapid solidification. These characteristics hinder the effective contact and bonding between jets with opposite charges, which is not conducive to the formation of a parallel yarn structure. When the viscosity of the spinning solution is too high, most of the friction fibers will exhibit severe adhesion and eventually merge into a single friction fiber with a larger diameter, which is not conducive to the formation of an oriented parallel yarn structure.

[0032] In some embodiments, the triboelectric polymer material is polyvinylidene fluoride. Polyvinylidene fluoride (PVDF) has a high dielectric constant and charge storage capacity. Its piezoelectricity can realize the direct conversion of mechanical energy into electrical energy, while the thermoelectric effect expands its energy collection capability in temperature-fluctuating environments. This multi-mechanism coupling enhances the environmental adaptability of TENG. PVDF is also an excellent electrical insulator, which can prevent leakage current from interfering with the charge separation process. Its electrical properties remain stable over a wide temperature range, making it suitable for applications in extreme environments. PVDF also has excellent mechanical and surface properties. PVDF has low surface tension and a low friction coefficient. It can operate without additional lubrication, which can reduce friction losses. It also has high tensile strength and impact strength, and can maintain structural integrity under mechanical stress, which helps to extend the service life of TENG. Moreover, PVDF is a flexible polymer material with strong processability and easy spinning, which is suitable for application in triboelectric yarns.

[0033] In some embodiments, the spinning solvent is a mixture of N,N-dimethylformamide and acetone, and the mass ratio of N,N-dimethylformamide to acetone is any value in the range of (1.3~1.7):1, for example, it can be any value in the range of (1.3:1), (1.4:1), (1.5:1), (1.6:1) and (1.7:1); the concentration of the triboelectric polymer material in the spinning solution is any value in the range of 14wt%~18wt%, for example, it can be any value in the range of 14wt%, 15wt%, 16wt%, 17wt% and 18wt%, which helps to regulate the viscosity of the spinning solution.

[0034] In some embodiments, the inner diameter of the needle of the syringe is any value between 0.5 mm and 0.8 mm, for example, it can be any value between 0.5 mm, 0.6 mm, 0.7 mm and 0.8 mm, the extrusion speed of the spinning solution in electrospinning is any value between 0.8 mL / h and 1.2 mL / h, for example, it can be any value between 0.8 mL / h, 0.9 mL / h, 1.0 mL / h, 1.1 mL / h and 1.2 mL / h, the collection speed of the triboelectric yarn is any value between 0.4 cm / s and 0.6 cm / s, for example, it can be any value between 0.4 rpm, 0.5 rpm and 0.6 rpm, the rotation speed of the metal funnel is any value between 200 rpm and 400 rpm, for example, it can be any value between 200 rpm, 240 rpm, 280 rpm, 320 rpm, 360 rpm and 400 rpm, and the spinning voltage of the electrospinning is any value between ±5.5 kV and ±7 kV. For example, the voltage may be any one of ±5.5 kV, ±6 kV, ±6.5 kV and ±7 kV. A set of optional electrospinning parameters is provided to help improve the quality of triboelectric yarn.

[0035] The present invention also provides a friction nano-power generation device, comprising a positive friction layer 1, a negative friction layer 23, an insulating substrate 3, an elastic support 4 and an external circuit. The positive friction layer 1 and / or the negative friction layer 23 include the above-mentioned friction electric yarn 21. The positive friction layer 1 and the negative friction layer 23 are respectively carried on two insulating substrates 3 and arranged opposite to each other. The two insulating substrates 3 are both carried on the elastic support 4, so that the positive friction layer 1 and the negative friction layer 23 can be controllably contacted or separated. When the positive friction layer 1 is in contact with the negative friction layer 23, electrons are transferred unidirectionally from the positive friction layer 1 to the negative friction layer 23, so that an electric potential difference is formed between the positive friction layer 1 and the negative friction layer 23 when they are separated. The external circuit is electrically connected to the positive friction layer 1 and / or the negative friction layer 23 for collecting current.

[0036] The formation of a friction nano-power generation device by the friction electric yarn 21 of the present invention helps to improve the sensitivity and power generation efficiency of the friction nano-power generation device, expands the applicable scenarios of the friction nano-power generation device, and improves the practicality of the friction nano-power generation device.

[0037] Please refer to the following examples for details.

[0038] Example 1: See Figure 1 The method for preparing the triboelectric yarn shown in a preferred embodiment of the present application comprises: S1. Dissolving the triboelectric polymer material in a prepared spinning solvent to obtain a spinning solution.

[0039] S2. Add the spinning solution into two syringes respectively, and pass the conductive core wire through the metal funnel, so that the two syringes with opposite voltages are simultaneously sprayed toward the conductive core wire for electrostatic spinning to form a friction layer covering the conductive core wire to obtain triboelectric yarn.

[0040] In step S1, PVDF was used as the triboelectric polymer material, and the spinning solvent was a mixture of N,N-dimethylformamide and acetone in a mass ratio of 3:2. PVDF powder was added to the spinning solvent in a 60°C water bath and stirred for 2 hours until the solution became clear, forming a spinning solution with a concentration of 16 wt%.

[0041] In step S2, a conjugate electrospinning method is used to form a friction layer on the surface of the conductive core wire with a spinning solution. The purchased silver-plated nylon yarn is fixed to the electrospinning equipment as the conductive core wire and passed through the metal funnel. The spinning solution is added to two 10mL syringes, which are respectively fixed to the injection pumps on both sides of the conductive core wire. Spinning voltages of +6kV and -6kV are applied to the two syringes, respectively. The spinning solution is extruded toward the metal funnel and the conductive core wire with a needle with an inner diameter of 0.61mm, and the extrusion speed of the spinning solution is 1mL / h. The wire body is collected in a direction away from the metal funnel at a collection speed of 0.5cm / s, and the metal funnel is rotated at a speed of 300rpm, so that the friction fibers formed by the jet of the spinning solution are adsorbed on the surface of the conductive core wire to form a friction layer, thereby obtaining a friction electric yarn.

[0042] See Figure 2 Take the friction electric yarn obtained in this embodiment, observe its cross section with an electron microscope, and magnify the part. It can be seen that multiple friction fibers are oriented and arranged, wrapped around the outer layer of the conductive core wire to form a friction layer. It can also be seen that there are many parallel wire structures inside the friction layer.

[0043] The triboelectric yarn 21 in this embodiment is used as the negative friction layer 23 to prepare a triboelectric nanoelectric device (TENG). Figure 3 The TENG includes a positive friction layer 1, a negative friction component 2, an insulating base 3, an elastic bracket 4, and an external circuit. The negative friction component 2 is formed by a triboelectric yarn 21 tightly and evenly wound on an insulating wire frame 22, i.e., a transparent acrylic sheet, and a commercially available Kapton film is used as the positive friction layer 1. In this embodiment, the winding area of ​​the triboelectric yarn 21 is 3 cm 3cm. The positive friction layer 1 and the negative friction component 2 are each insulated and connected to two insulating bases 3. The insulating bases 3 completely cover the surface of the positive friction layer 1 or the negative friction component 2 to prevent electrical charge leakage. The two insulating bases 3 are each connected to an elastic bracket 4. In this embodiment, the elastic bracket 4 includes a first bearing portion 41 and a second bearing portion 42 arranged horizontally opposite each other, as well as a first elastic portion 43 and a second elastic portion 44 connected between the first bearing portion 41 and the second bearing portion 42 and arranged opposite each other, giving the elastic bracket 4 a ring shape on a vertical plane. The two insulating bases 3 are respectively connected to the first bearing portion 41 and the second bearing portion 42, so that the positive friction layer 1 and the negative friction component 2 are arranged opposite each other, with a gap between them. The elastic bracket 4 in this embodiment is constructed of polyvinyl chloride (PVC), which is transparent and highly elastic. On the negative friction component 2, a layer of tightly arranged triboelectric yarns 21 opposite the positive friction layer 1 serves as the negative friction layer 23. When the elastic support 4 is subjected to vertical pressure, the positive friction layer 1 and the negative friction layer 23 come into contact. When the external force disappears, the elastic support 4 structure recovers, driving the positive friction layer 1 and the negative friction layer 23 to separate. The triboelectric yarns 21 are connected to an external circuit to collect electrical energy. One end of the triboelectric yarns 21 is grounded through the external circuit, and the other end is connected to an electrode through the external circuit.

[0044] See Figure 4 When the triboelectric yarn comes into contact with the Kapton film, due to the different electron affinities between the two, electrons are transferred unidirectionally from the Kapton film to the PVDF friction layer of the triboelectric yarn, making the PVDF negatively charged and the Kapton film positively charged. When the triboelectric yarn is separated from the Kapton film, electrostatic induction occurs under the action of the electric field formed by the potential difference between the two. Since the friction layer is negatively charged, the electrons carried by the conductive layer are driven to flow to the ground through the external circuit. When the maximum separation distance is reached, the charge reaches equilibrium and the electrons stop flowing. With the next application of external force, the triboelectric yarn and the Kapton film approach each other again, and electrons flow back from the ground, generating a reverse current. When the two layers come into contact, the charge is neutralized, completing a cycle, thereby generating a continuous AC output.

[0045] See Figure 5 , the open circuit voltage of TENG when different pressures are applied is detected and fitted into a standard curve. It can be seen that the TENG in this embodiment has high accuracy when used for pressure detection.

[0046] See Figure 6 The triboelectric yarn in this embodiment was sewn onto the surface of a glove. The output voltage and waveform were measured by flexing different fingers. The specific sewing method and experimental procedures are conventional and will not be detailed here. As can be seen from the figures, the triboelectric yarn in this embodiment has high sensitivity.

[0047] See Figure 7 The TENG was squeezed and released multiple times continuously to detect the change in its open-circuit voltage. As can be seen from the figure, the output performance of the TENG remained stable and had good output stability.

[0048] Example 2: The only difference between this embodiment and Example 1 is that the concentrations of the spinning dope in this embodiment were adjusted to 10wt%, 12wt%, 14wt%, 18wt%, and 20wt%, respectively. The viscosity of the spinning dope increased with its concentration. When the concentration of the spinning dope was 14wt%, the viscosity was 2652mPa·s, and when the concentration was 18wt%, the viscosity reached 5364mPa·s.

[0049] See Figure 8 Observation of the surfaces of the triboelectric yarns in this embodiment and Example 1 under an electron microscope revealed that when the spinning solution concentration was less than 14wt%, the friction fibers on the friction layer surface did not exhibit significant and widespread paralleling. When the spinning solution concentration was between 14wt% and 18wt%, paralleling was more common, and the diameter of the friction fibers was relatively uniform. When the spinning solution concentration was 16wt%, the orientation, uniformity, and paralleling rate of the friction fibers were excellent. When the spinning solution concentration was greater than 18wt%, severe adhesion between the friction fibers occurred, and the overall diameter of the friction fibers gradually increased.

[0050] See Figure 9 4 cm of each triboelectric yarn 21 from this example and Example 1 was bonded to the surface of an insulating wire frame 22 to form a negative friction assembly 2 and assembled to form a TENG. A pressure of 30 N was applied to each, and the open-circuit voltage of each TENG was measured. As can be seen from the figure, when the spinning solution concentration is 16 wt%, the TENG has a high output efficiency, demonstrating that the charge output performance of the triboelectric yarn 21 is closely related to the morphology of the triboelectric fiber.

[0051] Example 3: The only difference between this embodiment and the first embodiment is that the spinning voltages in this embodiment are adjusted to ±5 kV, ±5.5 kV, ±6.5 kV and ±7.5 kV respectively.

[0052] See Figure 10 The surfaces of the friction electric yarns in this embodiment and Example 1 were observed under an electron microscope. It can be seen that when the spinning voltage is lower than ±5.5kV or higher than ±7kV, the friction fibers on the surface of the friction electric yarn will show obvious uneven thickness, and the arrangement of the fibers is relatively disordered. When the spinning voltage is ±6kV, the orientation, uniformity and parallelization rate of the friction fibers are better.

[0053] Example 4: The only difference between this embodiment and the first embodiment is that the rotation speed of the metal funnel in this embodiment is adjusted to 100 rpm, 200 rpm, 400 rpm, 500 rpm and 600 rpm respectively.

[0054] See Figure 11 By observing the fiber cone surface formed on the metal funnel during electrospinning in this embodiment and embodiment 1, it can be seen that the higher the rotation speed of the metal funnel, the larger the top angle of the fiber cone surface, and the higher the tension of the friction fiber.

[0055] See Figure 12 The surfaces of the friction electric yarns in this embodiment and Example 1 were observed under an electron microscope. It can be seen that when the rotation speed of the metal funnel is in the range of 200rpm~400rpm, the friction fibers on the surface of the friction layer have better orientation, uniformity and parallelization rate, and the best result is when the rotation speed of the metal funnel is 300rpm.

[0056] The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0057] The above-described embodiments merely illustrate several implementations of the present invention, and while their descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent. It should be noted that a person skilled in the art would be able to make numerous variations and improvements without departing from the spirit of the present invention, all of which fall within the scope of protection of the present invention. Therefore, the scope of protection of the patent for this invention shall be determined by the appended claims.

Claims

1. A triboelectric yarn, characterized in that: It includes a conductive core wire and a friction layer wrapped around the outer layer of the conductive core wire. The friction layer includes multiple oriented friction fibers, and the multiple friction fibers are adhered to each other to form a parallel wire structure. The main component of the friction fiber is a triboelectric polymer material, and the triboelectric polymer has dielectric properties and spinnability.

2. The triboelectric yarn according to claim 1, wherein The triboelectric polymer material includes any one of polyvinylidene fluoride, polytetrafluoroethylene, polyurethane, polyacrylonitrile, polyimide, polylactic acid and chitosan.

3. The triboelectric yarn according to claim 1, wherein The conductive core wire is a flexible yarn with a conductive layer covered on its surface.

4. The triboelectric yarn according to claim 3, wherein The flexible yarn is made of nylon, and the conductive layer is made of elemental silver.

5. A method for preparing the triboelectric yarn according to any one of claims 1 to 4, characterized in that: include: dissolving the triboelectric polymer material in a matching spinning solvent to obtain a spinning solution; The spinning solution is added into two syringes respectively, and the conductive core wire is passed through a metal funnel, so that the two syringes with opposite voltages are simultaneously sprayed toward the conductive core wire for electrostatic spinning to form the friction layer covering the conductive core wire, thereby obtaining the friction electric yarn.

6. The method for preparing the triboelectric yarn according to claim 5, wherein: The viscosity of the spinning solution is any value between 2652 mPa·s and 5364 mPa·s.

7. The method for preparing the triboelectric yarn according to claim 5, wherein: The triboelectric polymer material is polyvinylidene fluoride.

8. The method for preparing the triboelectric yarn according to claim 7, wherein: The spinning solvent is a mixture of N,N-dimethylformamide and acetone, and the mass ratio of the N,N-dimethylformamide to the acetone is any value between (1.3 and 1.7):

1. The concentration of the triboelectric polymer material in the spinning solution is any value between 14wt% and 18wt%.

9. The method for preparing the triboelectric yarn according to claim 5, wherein: The inner diameter of the needle of the syringe is any value between 0.5 mm and 0.8 mm, the extrusion speed of the spinning solution in the electrospinning is any value between 0.8 mL / h and 1.2 mL / h, the collection speed of the triboelectric yarn is any value between 0.4 cm / s and 0.6 cm / s, the rotation speed of the metal funnel is any value between 200 rpm and 400 rpm, and the spinning voltage of the electrospinning is any value between ±5.5 kV and ±7 kV.

10. A triboelectric nano-power generation device, characterized in that: The invention comprises a positive friction layer (1), a negative friction layer (23), an insulating substrate (3), an elastic support (4) and an external circuit, wherein the positive friction layer (1) and / or the negative friction layer (23) comprise the friction electric yarn (21) as described in any one of claims 1 to 4, the positive friction layer (1) and the negative friction layer (23) are respectively carried on two insulating substrates (3) and arranged opposite to each other, and the two insulating substrates (3) are both carried on the elastic support (4), so that the positive friction layer (1) and the negative friction layer (23) can be controllably contacted or separated, when the positive friction layer (1) contacts the negative friction layer (23), electrons are unidirectionally transferred from the positive friction layer (1) to the negative friction layer (23), so that the positive friction layer (1) and the negative friction layer (23) form an electric potential difference when they are separated, and the external circuit is electrically connected to the positive friction layer (1) and / or the negative friction layer (23) for collecting current.

Images