A temperature-sensitive friction power generation material and a friction power generator

Abstract

The application discloses a kind of perception temperature-sensitive friction power generation materials, prepare as follows: S1, inorganic soluble salt is added to polyvinyl alcohol aqueous solution and mixed, and mixed liquor is obtained;S2, heated foaming powder is added to mixed liquor, air-dried, and foaming powder coated with polyvinyl alcohol and inorganic soluble salt on surface is obtained;S3, foaming powder coated with polyvinyl alcohol and inorganic soluble salt on surface is heated, then mixed with polydimethylsiloxane and curing agent, and after adding conductive filler and mixing uniformly, pour into mould, and solidification obtains polyhedral composite material;S4, polyhedral composite material is brushed with polydimethylsiloxane, curing agent on other surfaces except one surface, and heated and solidified, and friction power generation material is obtained.The friction power generator based on the material can realize heat power generation, and has larger output voltage.

Description

Technical Field

[0001] This invention belongs to the field of triboelectric power generation technology, and particularly relates to a temperature-sensitive triboelectric power generation material and a triboelectric generator. Background Technology

[0002] Considering the abundance of energy sources in the operating environment of electronic devices, such as solar energy, wind energy, sound, water flow, and friction, the original motivation for Academician Wang Zhonglin's 2006 proposal of a self-powered system was to enable the device to collect energy from the environment, thus allowing it to operate sustainably. Self-powered electronic information is also considered a future development trend.

[0003] For example, patent 202210025437.5 discloses a cellulose-based triboelectric nanogenerator and its preparation method. The positive electrode film of the nano-triboelectric generator is dissolved only with deionized water during the preparation process, which has good biocompatibility and degradability. The introduced hydroxyethyl cellulose can reduce the surface work function of the bacterial cellulose film, which can greatly improve the output performance of the prepared triboelectric nanogenerator while retaining the advantages of bacterial cellulose.

[0004] Current triboelectric generators rely on external mechanical forces to deform materials through compression and stretching, thereby generating electrons. However, in recent years, the rapid development of technologies such as wireless communication, functional materials, electronic information, and microelectromechanical systems (MEMS) has led to a surge in research interest in triboelectric generators that convert various forms of energy, such as heat and sound, into electrical energy, based on diverse power generation modes. Simultaneously, designing triboelectric nanogenerator structures to adapt to multiple application scenarios and improve output power is also a current research focus, posing new requirements for triboelectric generator structures. Summary of the Invention

[0005] Based on the above-mentioned technical problems, the present invention provides a temperature-sensitive triboelectric material and a triboelectric generator. The triboelectric generator is an integrated structure that can generate thermal power and has a large output voltage.

[0006] The specific solution of this invention is as follows:

[0007] This invention provides a temperature-sensitive triboelectric material, prepared by the following method:

[0008] S1. Add the inorganic soluble salt to the polyvinyl alcohol aqueous solution and mix to obtain a mixture;

[0009] S2. Add the heated foaming powder to the mixture and air dry to obtain foaming powder with polyvinyl alcohol and inorganic soluble salts coated on the surface; the heating temperature is 25-50℃, which is lower than the foaming temperature of the foaming powder.

[0010] S3. The foaming powder coated with polyvinyl alcohol and inorganic soluble salts is heated, then mixed with polydimethylsiloxane and a curing agent, and then conductive filler is added and mixed evenly before being poured into a mold and cured to obtain a polyhedral composite material; the heating temperature is lower than the foaming temperature of the foaming powder.

[0011] S4. Except for one surface, polydimethylsiloxane and curing agent are brushed onto the other surfaces of the polyhedral composite material, and then heated and cured to obtain the triboelectric power generation material; the heating and curing temperature is 100-300℃, which is higher than the foaming temperature of the foaming powder.

[0012] In steps S1 and S2 of this invention, a foamed powder coated with polyvinyl alcohol and inorganic soluble salts is obtained. In step S3, the foamed powder is heated and mixed with polydimethylsiloxane. Under its own heat, a layer of polydimethylsiloxane is coated and cured on its surface, and then dispersed in polydimethylsiloxane and conductive filler. Further, at the curing temperature described in S4, the foamed powder expands into a hollow microsphere structure, and the coating layer (containing polyvinyl alcohol and inorganic soluble salts) is in a highly elastic state. The resulting triboelectric power generation material structure is as follows: Figure 1 As shown, the inner layer is a hollow microsphere, the outer layer of the hollow microsphere is coated with an ion-containing polyvinyl alcohol film, and the outer shell is a polydimethylsiloxane layer.

[0013] Preferably, the inorganic soluble salt is selected from at least one of lithium chloride, sodium chloride, and zinc chloride; preferably, the mass fraction of the polyvinyl alcohol aqueous solution is 0.5-5%.

[0014] Preferably, the foaming powder is selected from at least one of polyurethane foaming powder, ammonium bicarbonate, and sodium bicarbonate.

[0015] The foaming temperature of the polyurethane foam powder described in this invention is 100°C.

[0016] Preferably, the conductive filler is selected from at least one of metal fibers, carbon fibers, and carbon nanotubes.

[0017] The addition of conductive filler in this invention not only improves the efficiency of heat conversion to electricity, but also facilitates the removal of positive and negative charges.

[0018] Preferably, in S3 and S4, the mass ratio of polydimethylsiloxane to curing agent is (17-40):1; preferably, in S3, the mass ratio of the foaming powder coated with polyvinyl alcohol and inorganic soluble salt to the sum of polydimethylsiloxane and curing agent is 0.1-0.8:1.

[0019] Preferably, in S4, the coating thickness is 0.05-0.8 cm.

[0020] Preferably, in S3, the mold shape is at least one of a cube, a cuboid, or a hexagonal prism.

[0021] The present invention also provides a triboelectric generator, which is an integrated triboelectric generator including a positive electrode and a negative electrode; the positive electrode material and the negative electrode material are both triboelectric materials described above; the negative electrode is obtained by fixing a metal plate to the surface of the triboelectric material coated with polydimethylsiloxane and a curing agent; the positive electrode is obtained by fixing a metal plate to the surface of the same triboelectric material that is not coated with polydimethylsiloxane and a curing agent.

[0022] Preferably, the metal plate is a copper plate.

[0023] Preferably, the triboelectric generator further includes wires.

[0024] The beneficial effects of this invention are:

[0025] This invention provides a temperature-sensitive triboelectric material and an integrated triboelectric generator based on this material. The triboelectric generator can convert heat energy into electrical energy, achieving thermal power generation, and has a large output voltage, adapting to application requirements in various scenarios.

[0026] The mechanism by which the triboelectric generator of the present invention achieves thermal power generation is as follows: the hollow microsphere with good closure can improve the scattering of solid phase phonons in the outer shell, which is converted into the vibration and internal energy (thermal expansion) of the outer polyvinyl alcohol film; when the triboelectric generator comes into contact with a heat source, since the gas expansion coefficient inside the hollow microsphere is higher than that of the surrounding solid material, it expands under heat and exerts tension on the polydimethylsiloxane wrapped in the outer layer. Under the elastic recovery of the polydimethylsiloxane, friction is achieved between the polyvinyl alcohol film and the polydimethylsiloxane.

[0027] In other words, during the heat transfer process inside the triboelectric generator, it is gradually converted into the vibration of the outer polyvinyl alcohol film. Due to the difference in elastic modulus between the polyvinyl alcohol film and the polydimethylsiloxane layer, it is further converted into the vibration between the polyvinyl alcohol film and the polydimethylsiloxane layer interface. Due to the difference in electron affinity between the two, combined with the structural design, the polydimethylsiloxane layer finally gains a large number of electrons and conducts them out, realizing thermal power generation. Attached Figure Description

[0028] Figure 1 This is a flowchart of the triboelectric power generation material and triboelectric generator process in Example 1;

[0029] Figure 2 This is a schematic diagram of the triboelectric material and triboelectric generator in Example 1;

[0030] Figure 3 The output voltage of the triboelectric generator described in Example 1 under different temperature heat sources;

[0031] Figure 4The output voltage of the triboelectric generator described in Example 2 under different temperature heat sources; Detailed Implementation

[0032] The technical solution of the present invention will be described in detail below through specific embodiments. However, it should be clearly stated that these embodiments are for illustrative purposes only and are not intended to limit the scope of the present invention.

[0033] Example 1

[0034] A temperature-sensitive triboelectric material is prepared as follows:

[0035] S1. Prepare a 1% polyvinyl alcohol aqueous solution and add 2g / L lithium chloride solution and mix well to obtain a mixture.

[0036] S2. Stir the polyurethane foam powder at 40°C and gradually add it to the above mixture. The process of assisting air drying yields polyurethane foam powder with polyvinyl alcohol and lithium chloride coated on the surface.

[0037] S3. Heat the polyurethane foam powder coated with polyvinyl alcohol and lithium chloride to 80°C, then mix it evenly with polydimethylsiloxane and dibutyl phthalate. Add 1% carbon fiber and stir evenly. Pour the mixture into a cuboid mold and cure to obtain a cuboid composite material. The mass ratio of polydimethylsiloxane to dibutyl phthalate is 20:1. The mass ratio of the polyurethane foam powder coated with polyvinyl alcohol and lithium chloride to (the sum of polydimethylsiloxane and dibutyl phthalate) is 0.2:1.

[0038] S4. Apply a 0.8 cm thick layer of polydimethylsiloxane and dibutyl phthalate mixed resin to the five surfaces of the cuboid composite material, and heat it at 120°C to cure it, so that the polyurethane foam powder foams to form hollow microspheres, thus obtaining the triboelectric material.

[0039] A triboelectric generator includes a positive electrode and a negative electrode; wherein: the negative electrode is obtained by attaching a copper plate to five surfaces of the above-mentioned cuboid triboelectric material coated with polydimethylsiloxane and dibutyl phthalate; the positive electrode is obtained by attaching a copper plate to the surface of the same triboelectric material that is not coated with polydimethylsiloxane and dibutyl phthalate.

[0040] The process flow diagram of this embodiment is as follows: Figure 1 As shown, the prepared triboelectric material and triboelectric generator structure are as follows. Figure 2 As shown.

[0041] The performance of the triboelectric generator in generating thermal energy was tested: an adjustable temperature heater was selected as the heat source, and an oscilloscope was used to characterize the output voltage of the triboelectric generator in this embodiment; the heat source was directly facing the triboelectric generator, the distance between the triboelectric generator and the heat source was 5cm, and the positive and negative leads were connected to the oscilloscope.

[0042] Test results are as follows Figure 3 As shown, when the heat source temperature is 60℃, 80℃, 100℃, and 120℃, the output voltage of the triboelectric generator is 1.0, 3.2, 5.7, and 7.9V, respectively, indicating that the triboelectric generator prepared by this invention can generate electricity from thermal energy and can achieve a large voltage output.

[0043] Example 2

[0044] A temperature-sensitive triboelectric material is prepared as follows:

[0045] S1. Prepare a 0.5% polyvinyl alcohol aqueous solution and add 6 g / L sodium chloride solution and mix well to obtain a mixture.

[0046] S2. The ammonium bicarbonate powder is stirred at 25°C and gradually added to the above mixture. The process of assisting air drying yields ammonium bicarbonate powder with polyvinyl alcohol and sodium chloride on the surface.

[0047] S3. Ammonium bicarbonate powder coated with polyvinyl alcohol and sodium chloride is heated to 30°C, then mixed evenly with polydimethylsiloxane and dibutyl phthalate. 5% metal fiber filler is then added and stirred evenly. The mixture is poured into a cubic mold and cured to obtain a cubic composite material. The mass ratio of polydimethylsiloxane to dibutyl phthalate is 17:1; the mass ratio of polyurethane foam powder coated with polyvinyl alcohol and sodium chloride to (the sum of polydimethylsiloxane and dibutyl phthalate) is 0.6:1.

[0048] S4. Apply a 0.1 cm thick layer of polydimethylsiloxane and dibutyl phthalate mixed resin to the five surfaces of the cubic composite material, and heat it at 110°C to cure it, causing the ammonium bicarbonate powder to decompose and expand, thus obtaining the triboelectric material.

[0049] A triboelectric generator includes a positive electrode and a negative electrode; wherein: the negative electrode is obtained by fixing copper plates to five surfaces of the cubic triboelectric material coated with polydimethylsiloxane and dibutyl phthalate; the positive electrode is obtained by attaching copper plates to the surface of the same triboelectric material that is not coated with polydimethylsiloxane and dibutyl phthalate.

[0050] The performance of the triboelectric generator in generating thermal energy was tested: an adjustable temperature heater was selected as the heat source, and an oscilloscope was used to characterize the output voltage of the triboelectric generator in this embodiment; the heat source was directly facing the triboelectric generator, the distance between the triboelectric generator and the heat source was 8cm, and the positive and negative leads were connected to the oscilloscope.

[0051] Test results are as follows Figure 4 As shown, when the heat source temperature is 45℃, 75℃, and 105℃, the output voltage of the triboelectric generator is 0.7, 1.6, and 2.9V, respectively, indicating that the triboelectric generator prepared by this invention can generate electricity from thermal energy and can achieve a large voltage output.

[0052] Example 3

[0053] A temperature-sensitive triboelectric material is prepared as follows:

[0054] S1. Prepare a 5% polyvinyl alcohol aqueous solution and add 8g / L zinc chloride solution, mix well to obtain a mixture;

[0055] S2. Sodium bicarbonate powder is stirred at 50°C and gradually added to the mixed solution. The process of assisting air drying yields sodium bicarbonate powder with polyvinyl alcohol and zinc chloride coated on the surface.

[0056] S3. Sodium bicarbonate powder coated with polyvinyl alcohol and zinc chloride is heated to 60°C, then mixed evenly with polydimethylsiloxane and dibutyl phthalate. 0.2% carbon nanotubes are then added and stirred evenly. The mixture is poured into a hexagonal prism mold and cured to obtain a hexagonal prism composite material. The mass ratio of polydimethylsiloxane to curing agent is 33:1; the mass ratio of sodium bicarbonate powder coated with polyvinyl alcohol and zinc chloride to (the sum of polydimethylsiloxane and dibutyl phthalate) is 0.26:1.

[0057] S4. Apply a 0.2cm thick layer of polydimethylsiloxane and dibutyl phthalate mixed resin to the five surfaces of the hexagonal prism composite material, and heat to 270℃ to cure, causing sodium bicarbonate to decompose and expand, thus obtaining the triboelectric material.

[0058] A triboelectric generator includes a positive electrode and a negative electrode; wherein: the negative electrode is obtained by attaching a copper plate to the surface of the above-mentioned hexagonal prism triboelectric material coated with polydimethylsiloxane and dibutyl phthalate; the positive electrode is obtained by attaching a copper plate to the surface of the same triboelectric material that is not coated with polydimethylsiloxane and dibutyl phthalate.

[0059] The performance of the triboelectric generator in generating thermal energy was tested: an adjustable temperature heater was selected as the heat source, and an oscilloscope was used to characterize the output voltage of the triboelectric generator in this embodiment; the heat source was directly facing the triboelectric generator, the distance between the triboelectric generator and the heat source was 2cm, and the positive and negative leads were connected to the oscilloscope.

[0060] When the heat source temperature is 60℃, 80℃, 100℃, and 120℃, the output voltage of the triboelectric generator is 1.1, 3.8, 6.4, and 11.1V, respectively, indicating that the triboelectric generator prepared by this invention can generate electricity from thermal energy and can achieve a large voltage output.

[0061] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A temperature-sensitive triboelectric power generation material, characterized in that, Prepared as follows: S1. Add the inorganic soluble salt to the polyvinyl alcohol aqueous solution and mix to obtain a mixture; S2. Add the heated foaming powder to the mixture and air dry to obtain foaming powder with polyvinyl alcohol and inorganic soluble salts coated on the surface; the heating temperature is 25-50℃, which is lower than the foaming temperature of the foaming powder. S3. The foaming powder coated with polyvinyl alcohol and inorganic soluble salts is heated, then mixed with polydimethylsiloxane and a curing agent, and then conductive filler is added and mixed evenly before being poured into a mold and cured to obtain a polyhedral composite material; the heating temperature is lower than the foaming temperature of the foaming powder. S4. Except for one surface, polydimethylsiloxane and curing agent are brushed onto the other surfaces of the polyhedral composite material, and then heated and cured to obtain the triboelectric power generation material; the heating and curing temperature is 100-300℃, which is higher than the foaming temperature of the foaming powder.

2. The temperature-sensitive triboelectric material according to claim 1, characterized in that, The inorganic soluble salt is selected from at least one of lithium chloride, sodium chloride, and zinc chloride; the mass fraction of the polyvinyl alcohol aqueous solution is 0.5-5%.

3. The temperature-sensitive triboelectric material according to claim 1 or 2, characterized in that, The foaming powder is selected from at least one of polyurethane foaming powder, ammonium bicarbonate, and sodium bicarbonate.

4. The temperature-sensitive triboelectric material according to claim 1 or 2, characterized in that, The conductive filler is selected from at least one of metal fiber, carbon fiber, and carbon nanotube.

5. The temperature-sensitive triboelectric material according to claim 1 or 2, characterized in that, In S3 and S4, the mass ratio of polydimethylsiloxane to curing agent is (17-40):1; in S3, the mass ratio of foaming powder coated with polyvinyl alcohol and inorganic soluble salt to the sum of polydimethylsiloxane and curing agent is (0.1-0.8):

1.

6. The temperature-sensitive triboelectric material according to claim 1 or 2, characterized in that, In S4, the coating thickness is 0.05-0.8cm.

7. The temperature-sensitive triboelectric material according to claim 1 or 2, characterized in that, In S3, the mold shape is at least one of a cube, cuboid, or hexagonal prism.

8. A triboelectric generator, characterized in that, The device is an integrated triboelectric generator, comprising a positive electrode and a negative electrode; both the positive electrode material and the negative electrode material are triboelectric materials as described in any one of claims 1-7; the negative electrode is obtained by fixing a metal plate to the surface of the triboelectric material coated with polydimethylsiloxane and a curing agent; the positive electrode is obtained by fixing a metal plate to the surface of the same triboelectric material that is not coated with polydimethylsiloxane and a curing agent.

9. The triboelectric generator according to claim 8, characterized in that, The metal plate is a copper plate.

10. The triboelectric generator according to claim 8 or 9, characterized in that, The triboelectric generator also includes wires.

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