High-output performance friction nanogenerator and preparation method thereof

Abstract

The application discloses a high-output-performance friction nanogenerator which is composed of a positive friction layer, a PDMS film layer one, a silver nanowire conductive structure, a PDMS film layer two, an electrode layer and a groove structure; a side surface of the PDMS film layer one is printed with a plurality of silver nanowire conductive structures to form a dielectric layer one; the other side surface of the PDMS film layer one is in contact with the positive friction layer when pressure is applied and is separated from the positive friction layer when the pressure is released; the electronegativity of the material of the positive friction layer is weaker than that of PDMS; a side surface of the PDMS film layer two is provided with a plurality of groove structures to form a dielectric layer two; the side surface of the PDMS film layer two with the groove structure is closely combined with the side surface of the PDMS film layer one with the silver nanowire conductive structure to form a negative friction layer; the other side surface of the PDMS film layer two is closely combined with the electrode layer. The application forms the negative friction layer by bonding the two dielectric layers, the groove structure is in contact with the silver nanowire conductive structure to form a charge trap, and the output performance of the friction nanogenerator is improved.

Description

Technical Field

[0001] This invention relates to the fields of additive manufacturing and micro / nano manufacturing, specifically to a high-output triboelectric nanogenerator and its preparation method. Background Technology

[0002] With the rapid depletion of fossil fuels, the energy crisis has become one of the major challenges facing society today. There is an urgent need to develop a green, efficient, and sustainable energy source to completely replace the dwindling fossil fuels. Triboelectric nanogenerators (TENGs), as energy harvesting devices that convert low-frequency mechanical energy into electrical energy, can collect minute amounts of mechanical energy from the environment, such as wind energy, sound wave energy, water wave energy, and the mechanical energy of human movement. Through triboelectric electrification, this mechanical energy is converted into electrical energy to power small electronic devices. Because these mechanical energy sources are widespread and pollution-free, triboelectric nanogenerators have the advantages of being green and sustainable, and have broad application prospects.

[0003] As an energy conversion device, the output performance of triboelectric nanogenerators determines their application fields, and surface charge density is a key factor affecting their application. Currently, researchers have proposed a series of strategies to improve the surface charge density of triboelectric nanogenerators, thereby expanding their application areas. For example, artificial charge injection can directly increase the surface charge density, but the injected charge dissipates quickly and has poor stability; doping with high-dielectric nanoparticles can affect the surface charge potential energy of triboelectric nanogenerators, thereby increasing the surface charge density, but the uneven distribution of doped particles and the inability to precisely control the doping process result in extremely poor reproducibility in the manufacture of such triboelectric nanogenerators; chemical surface modification to generate more electronegative functional groups on the surface of the triboelectric layer can also increase the surface charge density, but the process is complex and time-consuming, severely affecting the manufacturing efficiency of triboelectric nanogenerators. Summary of the Invention

[0004] To address the shortcomings of existing technologies, the technical problem this invention aims to solve is to provide a high-output triboelectric nanogenerator and its preparation method.

[0005] The technical solution of the present invention to solve the aforementioned technical problem is to provide a high-output performance triboelectric nanogenerator, characterized in that the triboelectric nanogenerator is composed of a positive triboelectric layer, a first PDMS film layer, a silver nanowire conductive structure, a second PDMS film layer, an electrode layer, and a groove structure.

[0006] One side surface of PDMS film layer one has several silver nanowire conductive structures printed on it, forming dielectric layer one; the other side surface of PDMS film layer one is in contact with the positive friction layer when pressure is applied and separates when pressure is released; the electronegativity of the material used in the positive friction layer is weaker than that of PDMS; the positive friction layer leads out to connect to an external load; one side surface of PDMS film layer two has several groove structures formed, forming dielectric layer two; the side surface of PDMS film layer two with groove structures is tightly bonded to the side surface of PDMS film layer one with silver nanowire conductive structures, forming negative friction layer; the other side surface of PDMS film layer two is tightly bonded to an electrode layer; the electrode layer leads out to connect to an external load.

[0007] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0008] (1) The present invention forms a dielectric layer one by printing a silver nanowire conductive structure on one side of a PDMS film layer one and forms a groove structure dielectric layer two on one side of a PDMS film layer two. The two dielectric layers are bonded to form a negative tribological layer. The groove structure contacts and separates from the silver nanowire conductive structure to form a charge trap, which enhances the electron capture capability of the dielectric layer, increases the surface charge density of the triboelectric nanogenerator, and effectively improves the output performance of the triboelectric nanogenerator.

[0009] (2) The present invention inserts a charge trap into the negative friction layer, so that the positive friction layer can be any material with a lower electronegativity than PDMS, or even a finger can be used directly instead, without the need for special design of the positive friction layer, so that the positive friction layer is no longer limited by materials and structures.

[0010] (3) This invention combines spin coating, electrohydrodynamic printing and transfer printing, and for the first time applies these three methods to the preparation process of charge traps in triboelectric nanogenerators. It is flexible and controllable, the charge traps formed are highly consistent in size, and the output performance of the prepared triboelectric nanogenerators is consistent, which can be mass-produced.

[0011] (4) The silver nanowire conductive structure of the present invention is prepared by electrohydrodynamic printing. Under the condition that the printing parameters remain unchanged, the size of the silver nanowire conductive structure of different triboelectric nanogenerators can be consistent, which has the advantages of rapid molding and high manufacturing repeatability.

[0012] (5) The dielectric layer 2 of the present invention is prepared by transfer printing. Its template can be used multiple times, and the dimensions and height of the transferred groove structure are consistent. Compared with other methods, it has the advantages of simple process, low cost and high manufacturing repeatability.

[0013] (6) The triboelectric nanogenerator prepared by the present invention has good working stability and high output performance. Moreover, the preparation process is simple, low cost and highly reproducible, making it suitable for large-scale production. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the triboelectric nanogenerator structure of the present invention;

[0015] Figure 2 This is a schematic diagram illustrating the working principle of the triboelectric nanogenerator of the present invention.

[0016] Figure 3 This is a cross-sectional electron microscope image of the negative friction layer of the triboelectric nanogenerator prepared in Example 4 of the present invention;

[0017] Figure 4 This is a photograph of the triboelectric nanogenerator prepared in Example 4 of the present invention.

[0018] Figure 5 The figures show the open-circuit voltage test results for Comparative Examples 1 to 5 of this invention; (in the figures, 378μm corresponds to Comparative Example 1, 330μm to Comparative Example 2, 284μm to Comparative Example 3, 240μm to Comparative Example 4, and 202μm to Comparative Example 5;)

[0019] Figure 6 The figures show the short-circuit current test results for Comparative Examples 1 to 5 of this invention; (in the figures, 378μm corresponds to Comparative Example 1, 330μm to Comparative Example 2, 284μm to Comparative Example 3, 240μm to Comparative Example 4, and 202μm to Comparative Example 5;)

[0020] Figure 7 The figures show the open-circuit voltage test results for Examples 1 to 5 of this invention; (in the figures, 378μm corresponds to Example 1, 330μm corresponds to Example 2, 284μm corresponds to Example 3, 240μm corresponds to Example 4, and 202μm corresponds to Example 5;)

[0021] Figure 8 These are the short-circuit current test results for Examples 1 to 5 of the present invention; (in the figures, 378μm corresponds to Example 1, 330μm to Example 2, 284μm to Example 3, 240μm to Example 4, and 202μm to Example 5;)

[0022] Figure 9 The results of surface charge density tests for Comparative Example 4 and Example 4 of this invention are shown.

[0023] In the figure, 1 is the positive friction layer, 2 is the first PDMS film, 3 is the silver nanowire conductive structure, 4 is the second PDMS film, 5 is the electrode layer, and 6 is the groove structure. Detailed Implementation

[0024] Specific embodiments of the present invention are given below. These specific embodiments are only used to further illustrate the present invention in detail and do not limit the scope of protection of the claims of the present invention.

[0025] This invention provides a high-output triboelectric nanogenerator (hereinafter referred to as triboelectric nanogenerator), characterized in that the triboelectric nanogenerator is composed of a positive triboelectric layer 1, a PDMS (polydimethylsiloxane) film layer 1 2, a silver nanowire conductive structure 3, a PDMS film layer 2 4, an electrode layer 5, and a groove structure 6.

[0026] One side surface of PDMS film layer 2 is printed with several silver nanowire conductive structures 3 (15-20 in this embodiment), forming dielectric layer 1; when the generator is working, the other side surface of PDMS film layer 2 contacts the positive friction layer 1 when pressure is applied and separates when pressure is released; the electronegativity of the material used in positive friction layer 1 is weaker than that of PDMS; wires are led out from positive friction layer 1 for connecting external loads; one side surface of PDMS film layer 4 is provided with several groove structures 6 (15-20 in this embodiment), forming dielectric layer 2; the side surface of PDMS film layer 4 with groove structures 6 and the side surface of PDMS film layer 2 with silver nanowire conductive structures 3 are bonded together to achieve a tight fit, with no gap between them, forming negative friction layer; the other side surface of PDMS film layer 4 is bonded together with electrode layer 5 to achieve a tight fit, with no gap between them, ensuring conductivity; wires are led out from electrode layer 5 for connecting external loads.

[0027] Preferably, the silver nanowire conductive structure 3 is printed on one side surface of the PDMS film layer 2 using electrohydrodynamic printing.

[0028] Preferably, the groove structure 6 is formed on one side surface of the PDMS film layer 4 by a transfer method.

[0029] Preferably, the silver nanowire conductive structures 3 are arranged parallel to each other and spaced apart, with a distance of 0.5 to 1 mm (preferably 1 mm) between two adjacent silver nanowire conductive structures 3; each silver nanowire conductive structure 3 has a width of 300 to 400 μm and a length of 10 to 20 mm.

[0030] Preferably, the groove structures 6 are parallel to each other and spaced apart, and the distance between two adjacent groove structures 6 is 0.5 to 1 mm (preferably 1 mm); each groove structure 6 has a width of 180 to 200 μm, a length of 10 to 20 mm (preferably 15 mm), a depth of 40 to 60 μm, and an arc-shaped cross-section.

[0031] Preferably, the angle between the silver nanowire conductive structure 3 and the groove structure 6 is consistent (preferably perpendicular to each other), so that the shape of their intersection is consistent (preferably square), thereby ensuring consistent output performance for each sample and high manufacturing repeatability.

[0032] Preferably, the thickness of PDMS film layer 2 and PDMS film layer 4 is the same, both being 101–189 μm.

[0033] Preferably, the positive friction layer 1 can be made of any material with weaker electronegativity than PDMS, such as metal, fabric, skin, etc. When the positive friction layer 1 comes into contact with PDMS, PDMS gains electrons, the positive friction layer 1 loses electrons, and the positive friction layer 1 becomes positively charged.

[0034] Preferably, to ensure the flexibility and light transmittance of the triboelectric nanogenerator, the electrode layer 5 uses a silver nanowire / PET transparent flexible conductive film.

[0035] Preferably, the positive friction layer 1, PDMS film layer 1, PDMS film layer 2, PDMS film layer 2, and electrode layer 5 have the same shape and the same length and width.

[0036] This invention also provides a method for preparing the high-output triboelectric nanogenerator (hereinafter referred to as the method), characterized in that the method includes the following steps:

[0037] (1) Cut the material of the positive friction layer 1 into an arbitrary shape (preferably square) and lead out the wires to form the positive friction layer 1;

[0038] Preferably, in step (1), when the shape of the positive friction layer 1 is a square, the side length is 10-20 mm.

[0039] (2) Mix the PDMS precursor and curing agent evenly at a mass ratio of 10:1 to prepare a PDMS solution;

[0040] (3) The PDMS solution obtained in step (2) is spin-coated onto a solid substrate at a speed of 300-700 rpm using a spin coater, and then heated at 60-70°C (preferably 70°C) for 14-20 min (preferably 20 min) to form a semi-cured PDMS film layer 2.

[0041] Preferably, in step (3), the solid substrate is made of glass, PET or acrylic (glass is preferred).

[0042] (4) Dissolve HPMC (hydroxypropyl methylcellulose) in deionized water and stir until completely dissolved to prepare an HPMC aqueous solution with a mass fraction of 1-5 wt% (preferably 2 wt%); then mix the HPMC aqueous solution with a silver nanowire aqueous solution containing 15-30 mg / ml (preferably 20 mg / ml) silver nanowires in any volume ratio to prepare an ink for printing silver nanowire conductive structures 3; then use electrohydrodynamic printing to print several ink lines on one side surface of the semi-cured PDMS film layer 2; after printing, wait for the water to completely evaporate to form several silver nanowire conductive structures 3 on one side surface of the PDMS film layer 2, forming dielectric layer 1;

[0043] Preferably, in step (4), the volume ratio of HPMC aqueous solution to silver nanowire aqueous solution is 1:9, 3:7, 1:1, 7:3 and 9:1.

[0044] Preferably, in step (4), the diameter of the silver nanowire is 80–200 nm.

[0045] Preferably, in step (4), the parameters of the electrohydrodynamic printing method are: needle inner diameter 250-280μm, DC voltage 1000-1200V, distance between needle and substrate 0.15-0.25mm, flow rate 3-5μL / min, printing speed 1-4mm / s, substrate temperature 40-60℃, and the printing path is set as 15-20 parallel and spaced straight lines with a length of 10-20mm, a spacing of 0.5-1mm, and a width of 300-400μm.

[0046] (5) Photoresist is printed on a solid substrate using electrohydrodynamic printing; after printing, the substrate is ventilated to allow the photoresist to fully cure, forming a mold with an array of raised lines.

[0047] Preferably, in step (5), the raised lines in the raised line array are parallel to each other and spaced apart, with a spacing of 0.5 to 1 mm and a quantity of 15 to 20; each raised line has a length of 10 to 20 mm, a width of 180 to 215 μm, and a height of 40 to 60 μm.

[0048] Preferably, in step (5), the photoresist used is a negative photoresist, preferably AZP4620 photoresist.

[0049] Preferably, in step (5), the parameters of the electrohydrodynamic printing method are: needle inner diameter 150-180μm, DC voltage 1100-1200V, needle-to-substrate distance 0.15-0.25mm, flow rate 0.15-0.25μL / min, printing speed 1-4mm / s, and the printing path is a linear array of 15-20 lines with a length of 10-20mm, a width of 180-215μm, a height of 40-60μm, and a spacing of 0.5-1mm.

[0050] (6) The PDMS solution obtained in step (2) is spin-coated onto a mold with a raised line array at a speed of 300-700 rpm using a spin coater; then heated at 85-90°C (preferably 90°C) for 20-25 min (preferably 20 min) to allow the PDMS to be completely cured; then the completely cured PDMS is peeled off from the mold and a PDMS film layer 2 4 with groove structure 6, i.e., dielectric layer 2, is transferred out;

[0051] (7) The side surface of PDMS film layer 2 with groove structure 6 is bonded to the side surface of PDMS film layer 1 with silver nanowire conductive structure 3 to form a negative friction layer; then heat at 85-90℃ for 15-20 minutes until PDMS film layer 1 is completely cured.

[0052] (8) Cut the material of electrode layer 5 into the same shape as positive friction layer 1 and the same length and width, and lead out wires to form electrode layer 5;

[0053] (9) The positive friction layer 1, the negative friction layer and the electrode layer 5 are assembled in sequence. The other side of the PDMS film layer 4 is bonded to the electrode layer 5 to achieve close contact. The other side of the PDMS film layer 2 faces the positive friction layer 1 to form a triboelectric nanogenerator.

[0054] Example 1

[0055] (1) Cut the copper foil into 15mm×15mm squares and lead out wires to form positive friction layer 1;

[0056] (2) Mix the PDMS precursor and curing agent evenly at a mass ratio of 10:1 to prepare a PDMS solution;

[0057] (3) The PDMS solution obtained in step (2) was spin-coated onto the glass substrate at a speed of 300 rpm using a spin coater, and then heated at 70°C for 20 min to form a semi-cured PDMS film layer 2 with a thickness of 189 μm.

[0058] (4) Dissolve HPMC in deionized water and stir until completely dissolved to prepare an HPMC aqueous solution with a mass fraction of 2wt%; then mix the HPMC aqueous solution with a silver nanowire aqueous solution containing 20mg / ml silver nanowires (silver nanowire diameter 120nm) at a volume ratio of 1:1 to prepare ink for printing silver nanowire conductive structures 3; then use electrohydrodynamic printing method to print several ink lines on one side surface of the semi-cured PDMS film layer 2; after printing, wait for the water to evaporate completely to form several silver nanowire conductive structures 3 on one side surface of the PDMS film layer 2, forming dielectric layer 1;

[0059] The parameters for electrohydrodynamic printing are: needle inner diameter 260μm, DC voltage 1000V, needle-to-substrate distance 0.2mm, flow rate 4μL / min, printing speed 2mm / s, substrate temperature 50℃, and the printing path is set as an array of 16 parallel and spaced straight lines with a length of 15mm, a spacing of 1mm, and a width of 300μm.

[0060] (5) Use electrohydrodynamic printing to print photoresist templates on glass substrates. After printing, place the templates in a ventilated area for 12 hours to allow the photoresist to fully cure, forming a mold with an array of raised lines.

[0061] The parameters for electrohydrodynamic printing are: needle inner diameter 150μm, DC voltage 1100V, needle-to-substrate distance 0.2mm, flow rate 0.2μL / min, printing speed 2mm / s, and the printing path is an array of 16 straight lines with a length of 15mm and a spacing of 1mm; the photoresist line width is 183μm and the height is 49μm.

[0062] (6) The PDMS solution obtained in step (2) is spin-coated onto a mold with a raised line array at a speed of 300 rpm using a spin coater; then the PDMS is cured at 90°C for 20 min in an oven to ensure complete curing; the fully cured PDMS is then peeled off from the mold and a PDMS film layer 2 4 with a thickness of 189 μm and a groove structure 6 is transferred out, which is the dielectric layer 2; the groove structure 6 has a width of 183 μm and a depth of 49 μm;

[0063] (7) The side surface of PDMS film layer 2 with groove structure 6 is bonded to the side surface of PDMS film layer 1 with silver nanowire conductive structure 3 to form a negative friction layer; then heat at 80°C for 20 minutes until PDMS film layer 1 is completely cured.

[0064] (8) Cut the silver nanowire / PET transparent flexible conductive film into a 15×15mm square and lead out wires to form an electrode layer 5;

[0065] (9) The positive friction layer 1, the negative friction layer and the electrode layer 5 are assembled in sequence. The other side of the PDMS film layer 4 is bonded to the electrode layer 5 to achieve close contact. The other side of the PDMS film layer 2 faces the positive friction layer 1 to form a triboelectric nanogenerator.

[0066] Tests showed that the open-circuit voltage across the triboelectric nanogenerator can reach a maximum of 90.81V, and the short-circuit current can reach a maximum of 1.13μA.

[0067] Example 2

[0068] (1) Cut the copper foil into 15mm×15mm squares and lead out wires to form positive friction layer 1;

[0069] (2) Mix the PDMS precursor and curing agent evenly at a mass ratio of 10:1 to prepare a PDMS solution;

[0070] (3) The PDMS solution obtained in step (2) was spin-coated onto the glass substrate at a speed of 400 rpm using a spin coater, and then heated at 70°C for 20 min to form a semi-cured PDMS film layer 2 with a thickness of 165 μm.

[0071] (4) Dissolve HPMC in deionized water and stir until completely dissolved to prepare an HPMC aqueous solution with a mass fraction of 2wt%; then mix the HPMC aqueous solution with a silver nanowire aqueous solution containing 20mg / ml silver nanowires (silver nanowire diameter 120nm) at a volume ratio of 1:1 to prepare ink for printing silver nanowire conductive structures 3; then use electrohydrodynamic printing method to print several ink lines on one side surface of the semi-cured PDMS film layer 2; after printing, wait for the water to evaporate completely to form several silver nanowire conductive structures 3 on one side surface of the PDMS film layer 2, forming dielectric layer 1;

[0072] The parameters for electrohydrodynamic printing are: needle inner diameter 260μm, DC voltage 1000V, needle-to-substrate distance 0.2mm, flow rate 4μL / min, printing speed 2mm / s, substrate temperature 50℃, and the printing path is set as an array of 16 parallel and spaced straight lines with a length of 15mm, a spacing of 1mm, and a width of 300μm.

[0073] (5) Use electrohydrodynamic printing to print photoresist templates on glass substrates. After printing, place the templates in a ventilated area for 12 hours to allow the photoresist to fully cure, forming a mold with an array of raised lines.

[0074] The parameters for electrohydrodynamic printing are: needle inner diameter 150μm, DC voltage 1100V, needle-to-substrate distance 0.2mm, flow rate 0.2μL / min, printing speed 2mm / s, and the printing path is an array of 16 straight lines with a length of 15mm and a spacing of 1mm; the photoresist line width is 183μm and the height is 49μm.

[0075] (6) The PDMS solution obtained in step (2) was spin-coated onto a mold with a raised line array at a speed of 400 rpm using a spin coater; then the PDMS was cured at 90°C for 20 min in an oven to ensure complete curing; the fully cured PDMS was then peeled off from the mold and a PDMS film layer 2 4 with a thickness of 165 μm and a groove structure 6 was transferred out, which is the dielectric layer 2; the groove structure 6 has a width of 183 μm and a depth of 49 μm;

[0076] (7) The side surface of PDMS film layer 2 with groove structure 6 is bonded to the side surface of PDMS film layer 1 with silver nanowire conductive structure 3 to form a negative friction layer; then heat at 80°C for 20 minutes until PDMS film layer 1 is completely cured.

[0077] (8) Cut the silver nanowire / PET transparent flexible conductive film into a 15×15mm square and lead out wires to form an electrode layer 5;

[0078] (9) The positive friction layer 1, the negative friction layer and the electrode layer 5 are assembled in sequence. The other side of the PDMS film layer 4 is bonded to the electrode layer 5 to achieve close contact. The other side of the PDMS film layer 2 faces the positive friction layer 1 to form a triboelectric nanogenerator.

[0079] Tests showed that the open-circuit voltage across the triboelectric nanogenerator can reach a maximum of 98.59V, and the short-circuit current can reach a maximum of 1.64μA.

[0080] Example 3

[0081] (1) Cut the copper foil into 15mm×15mm squares and lead out wires to form positive friction layer 1;

[0082] (2) Mix the PDMS precursor and curing agent evenly at a mass ratio of 10:1 to prepare a PDMS solution;

[0083] (3) The PDMS solution obtained in step (2) was spin-coated onto the glass substrate at a speed of 500 rpm using a spin coater, and then heated at 70°C for 20 min to form a semi-cured PDMS film layer 2 with a thickness of 142 μm.

[0084] (4) Dissolve HPMC in deionized water and stir until completely dissolved to prepare an HPMC aqueous solution with a mass fraction of 2wt%; then mix the HPMC aqueous solution with a silver nanowire aqueous solution containing 20mg / ml silver nanowires (silver nanowire diameter 120nm) at a volume ratio of 1:1 to prepare ink for printing silver nanowire conductive structures 3; then use electrohydrodynamic printing method to print several ink lines on one side surface of the semi-cured PDMS film layer 2; after printing, wait for the water to evaporate completely to form several silver nanowire conductive structures 3 on one side surface of the PDMS film layer 2, forming dielectric layer 1;

[0085] The parameters for electrohydrodynamic printing are: needle inner diameter 260μm, DC voltage 1000V, needle-to-substrate distance 0.2mm, flow rate 4μL / min, printing speed 2mm / s, substrate temperature 50℃, and the printing path is set as an array of 16 parallel and spaced straight lines with a length of 15mm, a spacing of 1mm, and a width of 300μm.

[0086] (5) Use electrohydrodynamic printing to print photoresist templates on glass substrates. After printing, place the templates in a ventilated area for 12 hours to allow the photoresist to fully cure, forming a mold with an array of raised lines.

[0087] The parameters for electrohydrodynamic printing are: needle inner diameter 150μm, DC voltage 1100V, needle-to-substrate distance 0.2mm, flow rate 0.2μL / min, printing speed 2mm / s, and the printing path is an array of 16 straight lines with a length of 15mm and a spacing of 1mm; the photoresist line width is 183μm and the height is 49μm.

[0088] (6) The PDMS solution obtained in step (2) is spin-coated onto a mold with a raised line array at a speed of 500 rpm using a spin coater; then the PDMS is cured at 90°C for 20 min in an oven to ensure complete curing; the fully cured PDMS is then peeled off from the mold and a PDMS film layer 2 4 with a thickness of 142 μm and groove structure 6 is transferred out, which is the dielectric layer 2; the groove structure 6 has a width of 183 μm and a depth of 49 μm;

[0089] (7) The side surface of PDMS film layer 2 with groove structure 6 is bonded to the side surface of PDMS film layer 1 with silver nanowire conductive structure 3 to form a negative friction layer; then heat at 80°C for 20 minutes until PDMS film layer 1 is completely cured.

[0090] (8) Cut the silver nanowire / PET transparent flexible conductive film into a 15×15mm square and lead out wires to form an electrode layer 5;

[0091] (9) The positive friction layer 1, the negative friction layer and the electrode layer 5 are assembled in sequence. The other side of the PDMS film layer 4 is bonded to the electrode layer 5 to achieve close contact. The other side of the PDMS film layer 2 faces the positive friction layer 1 to form a triboelectric nanogenerator.

[0092] Tests showed that the open-circuit voltage across the triboelectric nanogenerator can reach a maximum of 150.33V, and the short-circuit current can reach a maximum of 1.91μA.

[0093] Example 4

[0094] (1) Cut the copper foil into 15mm×15mm squares and lead out wires to form positive friction layer 1;

[0095] (2) Mix the PDMS precursor and curing agent evenly at a mass ratio of 10:1 to prepare a PDMS solution;

[0096] (3) The PDMS solution obtained in step (2) was spin-coated onto the glass substrate at a speed of 600 rpm using a spin coater, and then heated at 70°C for 20 min to form a semi-cured PDMS film layer 2 with a thickness of 120 μm.

[0097] (4) Dissolve HPMC in deionized water and stir until completely dissolved to prepare an HPMC aqueous solution with a mass fraction of 2wt%; then mix the HPMC aqueous solution with a silver nanowire aqueous solution containing 20mg / ml silver nanowires (silver nanowire diameter 120nm) at a volume ratio of 1:1 to prepare ink for printing silver nanowire conductive structures 3; then use electrohydrodynamic printing method to print several ink lines on one side surface of the semi-cured PDMS film layer 2; after printing, wait for the water to evaporate completely to form several silver nanowire conductive structures 3 on one side surface of the PDMS film layer 2, forming dielectric layer 1;

[0098] The parameters for electrohydrodynamic printing are: needle inner diameter 260μm, DC voltage 1000V, needle-to-substrate distance 0.2mm, flow rate 4μL / min, printing speed 2mm / s, substrate temperature 50℃, and the printing path is set as an array of 16 parallel and spaced straight lines with a length of 15mm, a spacing of 1mm, and a width of 300μm.

[0099] (5) Use electrohydrodynamic printing to print photoresist templates on glass substrates. After printing, place the templates in a ventilated area for 12 hours to allow the photoresist to fully cure, forming a mold with an array of raised lines.

[0100] The parameters for electrohydrodynamic printing are: needle inner diameter 150μm, DC voltage 1100V, needle-to-substrate distance 0.2mm, flow rate 0.2μL / min, printing speed 2mm / s, and the printing path is an array of 16 straight lines with a length of 15mm and a spacing of 1mm; the photoresist line width is 183μm and the height is 49μm.

[0101] (6) The PDMS solution obtained in step (2) was spin-coated onto a mold with a raised line array at a speed of 600 rpm using a spin coater; then the PDMS was cured at 90°C for 20 min in an oven to ensure complete curing; the fully cured PDMS was then peeled off from the mold and a PDMS film layer 2 4 with a thickness of 120 μm and groove structure 6 was transferred out, which is the dielectric layer 2; the groove structure 6 has a width of 183 μm and a depth of 49 μm;

[0102] (7) The side surface of PDMS film layer 2 with groove structure 6 is bonded to the side surface of PDMS film layer 1 with silver nanowire conductive structure 3 to form a negative friction layer; then heat at 80°C for 20 minutes until PDMS film layer 1 is completely cured.

[0103] (8) Cut the silver nanowire / PET transparent flexible conductive film into a 15×15mm square and lead out wires to form an electrode layer 5;

[0104] (9) The positive friction layer 1, the negative friction layer and the electrode layer 5 are assembled in sequence. The other side of the PDMS film layer 4 is bonded to the electrode layer 5 to achieve close contact. The other side of the PDMS film layer 2 faces the positive friction layer 1 to form a triboelectric nanogenerator.

[0105] Tests showed that the open-circuit voltage across the triboelectric nanogenerator can reach a maximum of 167.43V, and the short-circuit current can reach a maximum of 2.42μA.

[0106] Depend on Figure 3 As can be seen, the upper layer is PDMS film layer 1 2, and the lower layer is PDMS film layer 2 4 with groove structure 6. There is an extremely thin silver nanowire conductive structure 3 between PDMS film layer 1 2 and PDMS film layer 2 4.

[0107] Example 5

[0108] (1) Cut the copper foil into 15mm×15mm squares and lead out wires to form positive friction layer 1;

[0109] (2) Mix the PDMS precursor and curing agent evenly at a mass ratio of 10:1 to prepare a PDMS solution;

[0110] (3) The PDMS solution obtained in step (2) was spin-coated onto the glass substrate at a speed of 700 rpm using a spin coater, and then heated at 70°C for 20 min to form a semi-cured PDMS film layer 2 with a thickness of 101 μm.

[0111] (4) Dissolve HPMC in deionized water and stir until completely dissolved to prepare an HPMC aqueous solution with a mass fraction of 2wt%; then mix the HPMC aqueous solution with a silver nanowire aqueous solution containing 20mg / ml silver nanowires (silver nanowire diameter 120nm) at a volume ratio of 1:1 to prepare ink for printing silver nanowire conductive structures 3; then use electrohydrodynamic printing method to print several ink lines on one side surface of the semi-cured PDMS film layer 2; after printing, wait for the water to evaporate completely to form several silver nanowire conductive structures 3 on one side surface of the PDMS film layer 2, forming dielectric layer 1;

[0112] The parameters for electrohydrodynamic printing are: needle inner diameter 260μm, DC voltage 1000V, needle-to-substrate distance 0.2mm, flow rate 4μL / min, printing speed 2mm / s, substrate temperature 50℃, and the printing path is set as an array of 16 parallel and spaced straight lines with a length of 15mm, a spacing of 1mm, and a width of 300μm.

[0113] (5) Use electrohydrodynamic printing to print photoresist templates on glass substrates. After printing, place the templates in a ventilated area for 12 hours to allow the photoresist to fully cure, forming a mold with an array of raised lines.

[0114] The parameters for electrohydrodynamic printing are: needle inner diameter 150μm, DC voltage 1100V, needle-to-substrate distance 0.2mm, flow rate 0.2μL / min, printing speed 2mm / s, and the printing path is an array of 16 straight lines with a length of 15mm and a spacing of 1mm; the photoresist line width is 183μm and the height is 49μm.

[0115] (6) The PDMS solution obtained in step (2) was spin-coated onto a mold with a raised line array at a speed of 700 rpm using a spin coater; then the PDMS was cured at 90°C for 20 min in an oven to ensure complete curing; the fully cured PDMS was then peeled off from the mold and a PDMS film layer 2 4 with a thickness of 101 μm and groove structure 6 was transferred out, which is the dielectric layer 2; the groove structure 6 has a width of 183 μm and a depth of 49 μm;

[0116] (7) The side surface of PDMS film layer 2 with groove structure 6 is bonded to the side surface of PDMS film layer 1 with silver nanowire conductive structure 3 to form a negative friction layer; then heat at 80°C for 20 minutes until PDMS film layer 1 is completely cured.

[0117] (8) Cut the silver nanowire / PET transparent flexible conductive film into a 15×15mm square and lead out wires to form an electrode layer 5;

[0118] (9) The positive friction layer 1, the negative friction layer and the electrode layer 5 are assembled in sequence. The other side of the PDMS film layer 4 is bonded to the electrode layer 5 to achieve close contact. The other side of the PDMS film layer 2 faces the positive friction layer 1 to form a triboelectric nanogenerator.

[0119] Tests showed that the open-circuit voltage across the triboelectric nanogenerator can reach a maximum of 109.33V, and the short-circuit current can reach a maximum of 1.93μA.

[0120] Comparative Example 1

[0121] Same as in Example 1, the only difference being that the surface of the PDMS film layer 2 4 does not have the groove structure 6.

[0122] Comparative Example 2

[0123] Same as in Example 2, the only difference being that the surface of the PDMS film layer 4 does not have the groove structure 6.

[0124] Comparative Example 3

[0125] Same as in Example 3, the only difference being that the surface of the PDMS film layer 4 does not have the groove structure 6.

[0126] Comparative Example 4

[0127] Same as in Example 4, the only difference being that the surface of the PDMS film layer 2 4 does not have the groove structure 6.

[0128] Depend on Figure 9 It can be seen that the surface charge density of Example 4 with the charge trap structure is significantly higher than that of Comparative Example 4. Therefore, the charge trap structure can effectively improve the surface charge density.

[0129] Comparative Example 5

[0130] Same as in Example 5, the only difference being that the surface of the PDMS film layer 4 does not have the groove structure 6.

[0131] Depend on Figure 7 and Figure 8 It can be seen that as the thickness of the dielectric layer decreases, the open-circuit voltage and short-circuit current of the triboelectric nanogenerators prepared in Examples 1 to 5 both increase. When the film thickness is reduced to 202 μm, the open-circuit voltage and short-circuit current no longer increase, but instead decrease.

[0132] Depend on Figures 5-8 It can be seen that the maximum open-circuit voltage and short-circuit current of Examples 1 to 5 are 3.75 times and 4.2 times that of the corresponding proportions, respectively, proving that the insertion of charge traps increases the surface charge density, thereby effectively improving the output performance of the triboelectric nanogenerator.

[0133] The working principle of the triboelectric nanogenerator of the present invention (e.g.) Figure 2As shown in the diagram: When pressure is applied, the positive friction layer 1 contacts and rubs against the upper surface of the PDMS film layer 2, and electrons transfer from the surface of the positive friction layer 1 to the upper surface of the PDMS film layer 2. Simultaneously, the groove structure 6 of the PDMS film layer 4 is compressed, and the PDMS film layer 4 contacts and rubs against the silver nanowire conductive structure 3, and electrons transfer from the silver nanowire conductive structure 3 to the PDMS film layer 4. When the pressure is released, the groove structure 6 of the PDMS film layer 4 recovers, and the PDMS film layer 4 separates from the silver nanowire conductive structure 3, forming a dipole-like charge region. The charge trap formed by the dipole makes it easier for electrons to transfer from the surface of the positive friction layer 1 to the PDMS film layer 2. The upper surface of the PDMS film layer 2 is transferred, so the upper surface of the PDMS film layer 2 has more negative charge, while the surface of the corresponding positive friction layer 1 has more positive charge. When the positive friction layer 1 separates from the PDMS film layer 2, due to the potential difference between the positive friction layer 1 and the electrode layer 5, positive charge flows from the positive friction layer 1 to the electrode layer 5, forming a positive current. When the positive friction layer 1 reaches its farthest point, no current is formed due to the electrostatic shielding phenomenon. When pressure is applied again, the positive friction layer 1 approaches the PDMS film layer 2, the electrostatic shielding is broken, and the electrode layer 5 has more positive charge, thus forming a reverse current. If periodic contact separation is performed, a periodic alternating current signal can be generated.

[0134] Any aspects not covered in this invention are applicable to existing technologies.

Claims

1. A high-output triboelectric nanogenerator, characterized in that, The triboelectric nanogenerator consists of a positive triboelectric layer (1), a first PDMS film (2), a silver nanowire conductive structure (3), a second PDMS film (4), an electrode layer (5), and a groove structure (6); A plurality of silver nanowire conductive structures (3) are printed on one side surface of PDMS film layer 1 (2). The silver nanowire conductive structures (3) are parallel to each other and spaced apart to form dielectric layer 1. The other side surface of PDMS film layer 1 (2) is in contact with positive friction layer (1) when pressure is applied and separates when pressure is released. The electronegativity of the material used in positive friction layer (1) is weaker than that of PDMS. Lead wires are led out from positive friction layer (1) for connecting external load. A plurality of groove structures (6) are opened on one side surface of PDMS film layer 2 (4). The groove structures (6) are parallel to each other and spaced apart to form dielectric layer 2. The side surface of PDMS film layer 2 (4) with groove structure (6) is closely attached to the side surface of PDMS film layer 1 (2) with silver nanowire conductive structure (3) to form negative friction layer. The silver nanowire conductive structure (3) and the groove structure (6) are perpendicular to each other. The other side surface of PDMS film layer 2 (4) is closely attached to electrode layer (5). Lead wires are led out from electrode layer (5) for connecting external load. The distance between two adjacent silver nanowire conductive structures (3) is 0.5~1mm; the width of each silver nanowire conductive structure (3) is 300~400μm and the length is 10~20mm; The distance between two adjacent groove structures (6) is 0.5~1mm; the width of each groove structure (6) is 180~200μm, the length is 10~20mm, the depth is 40~60μm, and the cross-sectional shape is arc. The silver nanowire conductive structure (3) is printed on one side surface of PDMS film layer one (2) by electrohydrodynamic printing; the groove structure (6) is formed on one side surface of PDMS film layer two (4) by transfer printing. The positive friction layer (1) is made of metal, fabric or skin; The positive friction layer (1), PDMS film layer one (2), PDMS film layer two (4) and electrode layer (5) have the same shape and the same length and width dimensions.

2. A method for preparing the high-output performance triboelectric nanogenerator as described in claim 1, characterized in that, The method includes the following steps: (1) Cut the material of the positive friction layer (1) into any shape and lead out the wire to form the positive friction layer (1). (2) Mix the PDMS precursor and curing agent evenly at a mass ratio of 10:1 to prepare a PDMS solution; (3) Use a spin coater to spin coat the PDMS solution obtained in step (2) onto a solid substrate at a speed of 300~700 rpm, and then heat at 60~70℃ for 14~20 min to form a semi-cured PDMS film layer (2). (4) Dissolve HPMC in deionized water and stir until completely dissolved to prepare an HPMC aqueous solution with a mass fraction of 1~5wt%; then mix the HPMC aqueous solution with a silver nanowire aqueous solution containing 15~30mg / ml silver nanowires in any volume ratio to prepare ink for printing silver nanowire conductive structures (3); then use electrohydrodynamic printing method to print several ink lines on one side surface of the semi-cured PDMS film layer (2); after printing, wait for the water to evaporate completely to form several silver nanowire conductive structures (3) on one side surface of the PDMS film layer (2) to form dielectric layer one; (5) Photoresist is printed on a solid substrate using electrohydrodynamic printing. After the photoresist is completely cured, a mold with an array of raised lines is formed. (6) Use a spin coater to spin coat the PDMS solution obtained in step (2) onto a mold with a raised line array at a speed of 300~700 rpm; then heat at 85~90℃ for 20~25 min to allow the PDMS to be completely cured; then peel the completely cured PDMS off the mold and transfer the second PDMS film layer (4) with the groove structure (6), i.e., the second dielectric layer. (7) The side surface of PDMS film layer 2 (4) with groove structure (6) is bonded to the side surface of PDMS film layer 1 (2) with silver nanowire conductive structure (3) to form a negative friction layer; then heat at 85~90℃ for 15~20min until PDMS film layer 1 (2) is completely cured. (8) Cut the material of the electrode layer (5) into the same shape and length and width as the positive friction layer (1), and lead out the wires to form the electrode layer (5). (9) Assemble the positive friction layer (1), negative friction layer and electrode layer (5) in sequence. The other side of the PDMS film layer 2 (4) is bonded to the electrode layer (5) to achieve close contact. The other side of the PDMS film layer 1 (2) faces the positive friction layer (1) to form a triboelectric nanogenerator.

3. The method for preparing the high-output performance triboelectric nanogenerator according to claim 2, characterized in that, In steps (3) and (5), the solid substrate is made of glass, PET or acrylic. In step (4), the diameter of the silver nanowires is 80~200nm.

4. The method for preparing the high-output triboelectric nanogenerator according to claim 2, characterized in that, In step (4), the parameters of electrohydrodynamic printing are: needle inner diameter 250~280μm, DC voltage 1000~1200V, distance between needle and substrate 0.15~0.25mm, flow rate 3~5μL / min, printing speed 1~4mm / s, substrate temperature 40~60℃, and the printing path is set as an array of 15~20 parallel and spaced straight lines with a length of 10~20mm, a spacing of 0.5~1mm, and a width of 300~400μm. In step (5), the parameters of the electrohydrodynamic printing method are: needle inner diameter 150~180μm, DC voltage 1100~1200V, needle-to-substrate distance 0.15~0.25mm, flow rate 0.15~0.25μL / min, printing speed 1~4mm / s, and the printing path is a linear array of 15~20 lines with a length of 10~20mm, a width of 180~215μm, a height of 40~60μm, and a spacing of 0.5~1mm.

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