Droplet friction type nano-generator and method for manufacturing the same

Abstract

This invention provides a method for manufacturing a droplet friction type nano-generator that has excellent power generation capabilities, with an open-circuit voltage and output charge of 230V and 315nC from a single droplet, good moisture resistance, and good mechanical durability and acid / alkali corrosion resistance. [Solution] The manufacturing method includes: step 1, mixing PDMS with a curing agent to prepare a PDMS solution; step 2, mixing PTFE particles with ethanol and ultrasonically dispersing them to obtain a PTFE suspension; step 3, knife-coating the mixture onto the surface of a substrate, vacuuming, and drying to pre-cure; step 4, spraying the PTFE suspension onto the surface of the object obtained in step 3, drying, and curing to form a coating on the surface of the substrate; and step 5, placing a top electrode at an intermediate position on the surface of the object obtained in step 4.

Description

Technical Field

[0001] The present invention belongs to micro-nano generators and their manufacturing methods, and specifically belongs to droplet friction nano-generators and their manufacturing methods.

Background Art

[0002] Single-droplet friction nano-generators (LD-TENGs), as emerging energy harvesting technologies, have received extensive attention due to their low cost, high efficiency, and sustainability. This technology utilizes the frictional interaction between droplets and material surfaces to convert mechanical energy into electrical energy and provide energy for microelectronic devices, wearable devices, and smart sensors. However, LD-TENGs exhibit significant voltage output in dry environments, but their performance in humid environments faces multiple challenges. Particularly in high-humidity or liquid environments, rapid charge dissipation and a significant reduction in output voltage become prominent. The presence of moisture often causes charge leakage and charge movement on the friction surface, reducing the charge storage efficiency of the nano-generator and thereby limiting its performance. This charge dissipation phenomenon is one of the important factors restricting the performance of single-droplet friction nano-generators. The influence of moisture and water on the triboelectric effect is obvious, leading to unstable voltage output and further limiting the reliability and effectiveness in practical applications.

[0003] To address the above problems, researchers have proposed various improvement measures. For example, the physical packaging method effectively prevents the intrusion of moisture to protect the internal structure and charges of the friction nano-generator and extend its lifespan. However, the increase in packaging materials may lead to an increase in the volume and weight of the friction nano-generator, potentially affecting its flexibility and application range. Another water-assisted method utilizes the interaction between water and polymer triboelectric materials to improve the surface charge density and alleviate the charge dissipation problem caused by moisture. However, this method may not be able to provide sufficient mechanical strength to meet the requirements for the robustness and wear resistance of the friction nano-generator.

[0004] In recent years, superhydrophobic triboelectric materials have demonstrated unparalleled superiority in the field of advanced triboelectric materials due to their unique hydrophobic properties, excellent moisture resistance, and superior electrical performance. Key construction strategies for superhydrophobic materials include molecular design, component adjustment, and customization of surface microstructure, which significantly reduce the impact of moisture on charge and further improve output performance. However, maintaining material stability and durability in high-humidity environments remains a major challenge. For example, certain molecular structures may hydrolyze or decompose due to moisture, affecting the long-term stability of the material. Compatibility issues between materials can also lead to a reduction in overall performance. Furthermore, non-uniform microstructures can cause air layer rupture, reducing hydrophobicity, leading to instability in contact area and frictional force, ultimately resulting in non-uniform charge distribution and affecting triboelectric output efficiency. [Overview of the project] [Problems that the invention aims to solve]

[0005] Objective of the Invention: In order to overcome the shortcomings of the prior art, the objective of the present invention is to provide a method for manufacturing a droplet friction type nanogenerator that is high performance and resistant to high humidity. Another objective of the present invention is to provide a droplet friction type nanogenerator with good mechanical durability and acid-alkali corrosion resistance. [Means for solving the problem]

[0006] Technical proposal: The method for manufacturing a droplet friction type nano-generator described in the present invention is, Step 1 involves mixing PDMS with a curing agent to prepare a PDMS solution, mixing PTFE particles with ethanol, and performing ultrasonic dispersion to obtain a PTFE suspension. Step 2 involves mixing BaTiO3 (BTO) particles with a PDMS solution and performing ultrasonic dispersion to obtain a mixture. Step 3 involves knife-coating the mixture onto the surface of the substrate, vacuuming, and drying to pre-cur it. Step 4 involves spraying a PTFE suspension onto the surface of the material obtained in step 3, drying and curing it to form a coating on the surface of the substrate. Step 5 includes placing a top electrode at an intermediate position on the surface of the object obtained in Step 4 to obtain a droplet friction type nano-generator.

[0007] Furthermore, in step 1, the curing agent is one of dibutyl phthalate and dibutyltin dilaurate, and the mass ratio of PDMS to curing agent is 8 to 12:1. The PTFE particle diameter is 2 to 10 μm, preferably 3 μm, and the mass fraction of PTFE particles in the suspension is 5 to 20 wt%.

[0008] Furthermore, in step 2, the average particle size of the BaTiO3 particles is 50 to 500 nm, preferably 100 nm, the dielectric constant is 120, and the mass fraction of BaTiO3 particles in the mixture is 10 to 25 wt%, preferably 20 wt%.

[0009] Furthermore, ultrasonic dispersion operates at temperatures of 10-30°C, frequencies of 20-60kHz, and power of 60-120W.

[0010] Furthermore, in step 3, the substrate is one of the following: a PET thin film, a PVC thin film, or an ITO conductive thin film. The pressure after vacuuming is 0.04 to 0.08 MPa, and the pre-curing drying is performed at a temperature of 55 to 65°C for 10 to 15 minutes.

[0011] Furthermore, in step 4, the drying and curing process is performed at a temperature of 55-65°C for 2-4 hours, and the coating thickness is 150-300 μm. The spray volume is 2 ml or more.

[0012] Furthermore, in step 5, the top electrode is one of the following: conductive copper wire, conductive silver wire, or tin-plated copper wire, with a diameter of 0.8 to 1.2 mm and a length of 10 to 30 mm.

[0013] The droplet friction type nanogenerator obtained in the method for manufacturing a droplet friction type nanogenerator described in the present invention includes a substrate, a coating is provided on the surface of the substrate, and a top electrode is arranged on the surface of the coating. The coating is manufactured from BaTiO3, PDMS, and PTFE.

[0014] Manufacturing Principle: By doping PDMS with the high dielectric constant material BaTiO3, charge polarization can be effectively enhanced, the frictional charge accumulation capacity can be improved, and charge dissipation can be reduced. In addition, the strongly electronegative material PTFE sprayed on the surface increases the charge contact area, thereby optimizing the frictional charge transfer process and generating more frictional charge. Under the cooperative effect of enhanced charge accumulation and optimized charge transfer, enhanced TENG output performance is achieved, as shown in Figure 1. Furthermore, the PTFE particles sprayed during pre-curing are firmly embedded in the surface of the triboelectric material, forming a uniform micro-nano structure, providing stable superhydrophobicity and low adhesion properties. This effectively prevents surface charge dissipation due to moisture in the air in high humidity environments, thus avoiding a reduction in the output performance of the frictional nano-generator. [Effects of the Invention]

[0015] Beneficial effects: The present invention has the following remarkable features compared to the prior art.

[0016] 1. By doping with BaTiO3 and spraying with PTFE, a droplet friction type nano-generator with excellent power generation effect is manufactured, and the open-circuit voltage and output charge of a single droplet reach 230V and 315nC, respectively.

[0017] 2. By spraying PTFE particles onto the surface, the triboelectric material is given superhydrophobic and low adhesive properties, allowing the droplet friction type nano-generator to exhibit excellent moisture resistance, maintain 90% of its initial power output even in a high humidity environment of 90% RH, and achieve open-circuit voltage and output charge of 207V and 285nC.

[0018] 3. The superhydrophobic surface produced by the preliminary curing spray has excellent mechanical durability and acid and alkali corrosion resistance, and still has good superhydrophobicity after sandpaper abrasion, scribing, and acid and alkali corrosion. Thus, even after undergoing the above-mentioned damage, the droplet friction type nanogenerator does not show a明显 deterioration in moisture resistance.

Brief Description of the Drawings

[0019] [Figure 1] It is a schematic diagram of the principle of the present invention. [Figure 2] It is a schematic structural diagram of the present invention. [Figure 3] It is a schematic structural diagram of the coating 2 of the present invention. [Figure 4] It is a diagram showing the open-circuit voltage effect of the droplet friction type nanogenerator under different BTO doping concentrations of the present invention. [Figure 5] It is a diagram showing the short-circuit current effect of the droplet friction type nanogenerator under different BTO doping concentrations of the present invention. [Figure 6] It is a diagram showing the output charge effect of the droplet friction type nanogenerator under different BTO doping concentrations of the present invention. [Figure 7] It is a surface SEM diagram of Comparative Example 1 of the present invention. [Figure 8] It is a contact angle diagram of Comparative Example 1 of the present invention. [Figure 9] It is a diagram showing the open-circuit voltage effect of the droplet friction type nanogenerator under different PTFE spray concentrations of the present invention. [Figure 10] It is a diagram showing the short-circuit current effect of the droplet friction type nanogenerator under different PTFE spray concentrations of the present invention. [Figure 11] It is a diagram showing the output charge effect of the droplet friction type nanogenerator under different PTFE spray concentrations of the present invention. [Figure 12] It is a surface SEM diagram of Example 7 of the present invention. [Figure 13] It is a contact angle diagram of Example 7 of the present invention. [Figure 14] It is a roll angle diagram of Example 7 of the present invention. [Figure 15]This diagram shows the power generation effect of the droplet friction type nano-generator before and after spraying under different humidity conditions in Test Example 1 of the present invention, where (a) is after spraying and (b) is before spraying. [Figure 16] This diagram shows the change in contact angle during sandpaper wear in Test Example 2 of the present invention. [Figure 17] This diagram shows the power generation effect after different surface treatments in Test Example 2 of the present invention. [Figure 18] These are diagrams showing the change in contact angle at different pH levels in Test Example 2 of the present invention, where (a) pH=14, (b) pH=7, and (c) pH=2. [Figure 19] This diagram shows the power generation effect at different pH levels in Test Example 2 of the present invention. [Figure 20] This diagram shows the effect of open-circuit voltage under different humidity conditions after mechanical damage and acid-alkali corrosion in Test Example 3 of the present invention, where (a) is after mechanical damage and (b) is after acid-alkali corrosion. [Figure 21] This is a diagram of the generated voltage over a long period of time in Test Example 4 of the present invention. [Figure 22] This is a contact angle diagram in Test Example 4 of the present invention. [Figure 23] This diagram shows the change in generated voltage at different lengths of storage in Test Example 4 of the present invention. [Figure 24] This diagram shows the power generation effect when the FEP suspension in Comparative Example 2 of the present invention is sprayed. [Figure 25] This is an open-circuit voltage diagram when other nanoparticles were doped in Comparative Example 3 of the present invention. [Figure 26] This is a surface contact angle diagram for Comparative Example 4 of the present invention, where PVA is used as the substrate. [Modes for carrying out the invention]

[0020] The materials, reagents, and equipment used in the following examples can be obtained through commercial channels unless otherwise specified. Experimental methods for which specific conditions are not explicitly stated in the examples generally follow standard conditions or conditions suggested by the manufacturer.

[0021] Example 1 The method for manufacturing a droplet friction type nanogenerator included the following steps. (1) A PDMS solution was prepared by mixing PDMS and the curing agent dibutyl phthalate in a mass ratio of 10:1. PTFE particles with an average particle size of 3 μm were mixed with ethanol, and ultrasonic dispersion was performed for 20 minutes at 20°C with an ultrasonic frequency of 40 kHz and an ultrasonic power of 100 W to obtain a PTFE suspension with a mass fraction of 15 wt%.

[0022] (2) BTO particles with a mass fraction of 10 wt% and an average particle size of 100 nm were mixed with a PDMS solution, and each mixture was subjected to ultrasonic dispersion for 5 minutes at an ultrasonic temperature of 20°C, an ultrasonic frequency of 40 kHz, and an output power of 100 W to obtain a mixture.

[0023] (3) 5 ml of the mixture obtained in step (2) was knife-coated onto the surface of an ITO conductive thin film measuring 30 mm x 60 mm x 0.125 mm, and then vacuum-embedded under a pressure of 0.08 MPa for 20 minutes, followed by drying at 60°C for 12 minutes to cure and mold.

[0024] (4) A 5 ml PTFE suspension was sprayed onto the surface of the material obtained in step (3), and cured by drying at 60°C for 3 hours to form a 200 μm thick coating 2 on the surface of the ITO conductive thin film substrate 1.

[0025] (5) A tin-plated copper wire with a diameter of 1.2 mm and a length of 30 mm was placed as the top electrode 3 at the midpoint of the four sample surfaces obtained in step (3), thereby obtaining four sets of droplet friction type nano-generators.

[0026] As shown in Figures 2-3, the droplet friction type nano-generator obtained in this embodiment had a coating 2 on the ITO conductive thin film substrate 1, the PTFE of coating 2 was embedded on the BTO-PDMS surface, and a top electrode 3 was located in the center of the surface of coating 2.

[0027] Example 2 The other steps of this embodiment were the same as those of Embodiment 1, the only difference being that the BTO mass fraction in step (2) was 15 wt%.

[0028] Example 3 The other steps of this embodiment were the same as those of Embodiment 1, the only difference being that the BTO mass fraction in step (2) was 20 wt%.

[0029] Example 4 The other steps of this embodiment were the same as those of Embodiment 1, the only difference being that the BTO mass fraction in step (2) was 25 wt%.

[0030] The power generation effect of the friction nanogenerators obtained in Examples 1-4 was measured, and the results are shown in Figures 4-6. As the BTO mass fraction increased from 10% to 20%, the output charge of the droplet friction nanogenerator increased from 59 nC to 88 nC, an increase of approximately 1.5 times. At the same time, the open-circuit voltage and short-circuit current increased from 51 V and 190 nA to 71 V and 226 nA, respectively, thanks to the doping of BTO and its uniform dispersion. The doped BTO effectively improved the relative dielectric constant of the material, giving it strong charge polarization capability, thereby accumulating more charge during the friction process, reducing charge dissipation, and converting it into even higher output. As the BTO mass fraction further increased to 25%, the output performance of the TENG remained essentially unchanged. This was presumed to be because excessive BTO doping resulted in uneven dispersion in the triboelectric material, leading to aggregation and preventing the effective improvement of the relative dielectric constant of the material, thus preventing further improvement in the output charge of the TENG. It was found that the optimal mass percentage for BTO (Build-to-Order) is 20 wt%.

[0031] Comparative Example 1 The other steps in this comparative example were the same as in Example 3, the only difference being that step (4) was omitted and the pre-curing time in step (3) was replaced with 3 hours. The surface morphology was observed using a cold cathode scanning electron microscope (SEM), and the results of the contact angle test are shown in Figure 7. Uniformly distributed BTO particles with a diameter of approximately 100 nm were exposed on the surface of the doped triboelectric material. This indicates that the high dielectric constant material was successfully introduced into the friction layer, which was advantageous in increasing the number of polarization charges and improving the output performance of the droplet friction nanogenerator. As shown in Figure 8, due to the lack of prominence of the micro-nanostructure by the BTO particles on the surface and the inherent hydrophilic properties of BTO, the contact angle of the sample was only 116°, which did not reach superhydrophobicity and could not improve the moisture resistance of the droplet friction nanogenerator.

[0032] Example 5 The method for manufacturing a droplet friction type nanogenerator included the following steps.

[0033] (1) A PDMS solution was prepared by mixing PDMS and dibutyl phthalate in a mass ratio of 10:1. PTFE particles with an average particle size of 3 μm and a mass fraction of 5 wt% were mixed with ethanol. Then, the four prepared mixtures were subjected to ultrasonic dispersion for 20 minutes at an ultrasonic temperature of 20°C, an ultrasonic frequency of 40 kHz, and an output power of 100 W to obtain a PTFE suspension.

[0034] (2) BTO particles with a diameter of 100 nm and a BTO mass fraction of 20 wt% were mixed with PDMS solution in different ratios. Then, ultrasonic dispersion was performed for 5 minutes at an ultrasonic temperature of 20°C, an ultrasonic frequency of 40 kHz, and an output power of 100 W to obtain the mixture.

[0035] (3) 5 ml of the mixture obtained in step (2) was knife-coated onto an ITO conductive thin film surface measuring 30 mm x 60 mm x 0.125 mm, and then vacuumed under a pressure of 0.08 MPa for 15 minutes and pre-cured at 60°C for 12 minutes.

[0036] (4) 5 ml each of the four suspensions from step (3) was sprayed onto the pre-cured surface from step (3), and cured by drying at 60°C for 3 hours to obtain four samples, each with a coating thickness of approximately 200 μm.

[0037] (5) A tin-plated copper wire with a diameter of 1.2 mm and a length of 30 mm was placed as the top electrode 3 at the midpoint of the four sample surfaces obtained in step (4), thereby obtaining four sets of droplet friction type nano-generators.

[0038] Example 6 The other steps of this embodiment were the same as those of Example 5, the only difference being that the PTFE mass fraction in step (1) was 10 wt%.

[0039] Example 7 The other steps of this embodiment were the same as those of Example 5, the only difference being that the PTFE mass fraction in step (1) was 15 wt%.

[0040] Example 8 The other steps of this embodiment were the same as those of Example 5, the only difference being that the PTFE mass fraction in step (1) was 20 wt%.

[0041] The power generation effect of the friction nano-generators obtained in Examples 5-8 was measured, and the results are shown in Figures 9-11. The output charge steadily increased with increasing concentration of sprayed PTFE particles, and when the mass fraction reached 15%, it increased from 145 nC to 315 nC, an improvement of 217%. This is a 358% improvement compared to the maximum output of 88 nC before PTFE spraying in Example 3. At the same time, the open-circuit voltage and short-circuit current increased from 110 V and 340 nA to 230 V and 420 nA, respectively, an improvement of 209% and 123%. This is because, with increasing spray concentration, more PTFE particles were embedded on the surface of the triboelectric material, increasing the number of triboelectric contact areas, and the surface fluorine element content also improved, generating more moving charge and thus a higher output charge. When the spray concentration was increased to 20 wt%, the output charge decreased, which can be explained by the uniformity of the surface particle dispersion. As the concentration of PTFE particles sprayed on the surface increased further, the fluorine element content on the surface of the triboelectric material increased, but the particles were coated with each other, reducing the solid-liquid contact area during the friction process, decreasing the moving charge, and thus reducing the output charge.

[0042] The surface morphology of droplet friction nanogenerators fabricated with PTFE at a mass fraction of 15 wt% was observed using a cold cathode scanning electron microscope, and the results are shown in Figure 12. After spraying, the PTFE was uniformly embedded in the surface with a particle diameter of <5 μm, which meant that the highly electronegative PTFE participated in the frictional electromotive force during the friction process, helping to improve the amount of frictional charge transfer. The semi-cured spraying process described herein utilizes the liquid properties of PDMS in the semi-cured state, allowing PTFE particles to settle on the semi-cured surface and be embedded in the surface after curing. The semi-cured PDMS also functions as an adhesive, forming adhesive bridges between different PTFE particles. Furthermore, the sprayed PTFE particles constructed a prominent micro-nanostructure on the surface, giving the friction layer superhydrophobicity and low adhesive properties. As shown in Figures 13-14, the contact angle was high at 164° and the roll angle was low at 3°, which helped to enhance the moisture resistance of the droplet friction nanogenerator. The optimal mass fraction of PTFE was 15 wt%.

[0043] Test Example 1 To verify that the droplet friction type nano-generator of the present invention maintains a good power generation effect in a high humidity environment, the power generation effect was tested under different environmental relative humidity (RH) conditions using the samples obtained in Comparative Example 1 and Example 7. The specific humidity levels were 50%RH, 60%RH, 70%RH, 80%RH, and 90%RH.

[0044] As shown in Figure 15, when the relative humidity increased from 50% to 90%, the output voltage and charge of the unsprayed sample decreased sharply by approximately 60%. In contrast, the sprayed sample showed a slight reduction in open-circuit voltage, short-circuit current, and output charge, maintaining approximately 90% of its initial power output at 90% relative humidity, reaching 207V, 404nA, and 285nC. This demonstrates that the droplet friction type nanogenerator of the present invention has excellent moisture resistance, because the sprayed PTFE particles construct a uniform micro-nano structure on the friction layer surface, providing superhydrophobicity and low adhesion properties. Under high humidity conditions, this effectively repels water, ensures surface dryness, reduces charge dissipation, and mitigates the impact of high humidity on TENG output performance.

[0045] Test Example 2 To verify the mechanical durability and chemical corrosion resistance of the surface spray structure of the present invention, sandpaper abrasion, scribing, and acid-alkali corrosion experiments were performed using the samples obtained in Example 7, and the contact angle change and power generation effect were measured.

[0046] As shown in Figure 16, the rate of decrease in the contact angle gradually slowed with increasing friction cycles, remaining above 155° even after 34 cycles, and the roll angle improved to 6°. This is because, during the friction process, the shallow particles embedded in the surface detach first, protecting the deeper particles, while the deeper particles become firmly embedded in the coating and less likely to detach, thereby slowing the decrease in the contact angle during later friction. The output performance of the TENG after sandpaper wear and blade scribing was tested, and as shown in Figure 17, the output voltage after sandpaper wear was 160V, and the output voltage after blade scribing was 200V, still maintaining a high power generation effect, thereby demonstrating the mechanical stability of the PTFE particles embedded in the surface.

[0047] The samples were immersed in HCl solution (pH=2), deionized water, and NaOH solution (pH=14), and the process of contact angle change is shown in Figure 18. With increasing immersion time, the contact angle decreased slightly and remained above 148° even after immersion in strong alkali for 60 hours and strong acid for 86 hours. The power output performance of the triboelectric material after corrosion was tested, and as shown in Figure 19, after acid-alkali corrosion, the output charges were 180V and 170V, respectively, still showing excellent power output performance. This is closely related to the functional embedding of PTFE particles, and the chemical inertness of PTFE and uniform dispersion on the surface gave the triboelectric material excellent corrosion resistance. In summary, these robustness tests demonstrated the adaptability of TENG to various types of damage that may be encountered in energy collection applications.

[0048] Test Example 3 To verify that the droplet friction type nano-generator of the present invention retains good moisture resistance even after its surface is damaged, the power generation effect was tested under different environmental relative humidity (RH) conditions using samples from Test Example 2 that had undergone mechanical damage and acid-alkali corrosion. The specific humidity levels were 50%RH, 60%RH, 70%RH, 80%RH, and 90%RH. As shown in Figure 20, the triboelectric material exhibited excellent moisture resistance even after mechanical and chemical destruction, and even in a high-humidity environment of 90%RH, the reduction in output performance did not exceed 20%, demonstrating its potential to operate in extremely harsh environments.

[0049] Test Example 4 Using the sample obtained in Example 7, we conducted power generation tests for long periods of continuous operation and for different durations to verify the durability and stability of the droplet friction type nano-generator. The results are shown in Figures 21-23. In the droplet friction test, which involved more than 6300 cycles, the output voltage remained fundamentally stable, and the contact angle at the droplet impact point exceeded 155°, demonstrating the durability of the surface-embedded structure. Furthermore, even after being left unattended for 12 days, CS-TENG was able to stably output a voltage of 195V. This high level of stability demonstrates that CS-TENG has broad application prospects in actual applications.

[0050] Example 9 The method for manufacturing a droplet friction type nanogenerator included the following steps.

[0051] (1) A PDMS solution was prepared by mixing PDMS and the curing agent dibutyltin dilaurate in a mass ratio of 8:1. PTFE particles with an average particle size of 3 μm were mixed with ethanol, and ultrasonic dispersion was performed for 20 minutes at 10°C with an ultrasonic frequency of 20 kHz and an ultrasonic power of 60 W to obtain a PTFE suspension with a mass fraction of 8 wt%.

[0052] (2) BTO particles with an average particle size of 50 nm were mixed with a PDMS solution, and ultrasonic dispersion was performed for 5 minutes at 10°C with an ultrasonic frequency of 20 kHz and an ultrasonic power of 60 W to obtain a mixture in which the mass fraction of BTO particles was 16 wt%.

[0053] (3) The mixture was knife-coated onto the surface of the PET thin film substrate 1, vacuumed under a pressure of 0.04 MPa for 20 minutes, and dried at 55°C for 10 minutes to pre-cur it.

[0054] (4) A 2 ml PTFE suspension was sprayed onto the surface of the material obtained in step (3), and cured by drying at 55°C for 4 hours to form a 150 μm thick coating 2 on the surface of the substrate 1.

[0055] (5) A conductive copper wire with a diameter of 0.8 mm and a length of 10 mm was placed as the top electrode 3 at the midpoint of the surface of the material obtained in step (4), thereby obtaining a droplet friction type nano-generator.

[0056] Example 10 The method for manufacturing a droplet friction type nanogenerator included the following steps. (1) A PDMS solution was prepared by mixing PDMS and the curing agent dibutyltin dilaurate in a mass ratio of 12:1. PTFE particles with an average particle size of 3 μm were mixed with ethanol, and ultrasonic dispersion was performed for 20 minutes at 30°C with an ultrasonic frequency of 60 kHz and an ultrasonic power of 120 W to obtain a PTFE suspension with a mass fraction of 18 wt%.

[0057] (2) BTO particles with an average particle size of 500 nm were mixed with a PDMS solution, and ultrasonic dispersion was performed at 30°C with an ultrasonic frequency of 60 kHz and an ultrasonic power of 120 W for 5 minutes to obtain a mixture in which the mass fraction of BTO particles was 23 wt%.

[0058] (3) The mixture was knife-coated onto the surface of the PVC thin film substrate 1, vacuumed under a pressure of 0.06 MPa for 20 minutes, and dried at 65°C for 15 minutes to pre-cur it.

[0059] (4) A 4 ml PTFE suspension was sprayed onto the surface of the material obtained in step (3), and cured by drying at 65°C for 2 hours to form a 300 μm thick coating 2 on the surface of the substrate 1.

[0060] (5) A conductive silver wire with a diameter of 1.0 mm and a length of 20 mm was placed as the top electrode 3 at the midpoint of the surface of the material obtained in step (4), thereby obtaining a droplet friction type nano-generator.

[0061] Comparative Example 2 The other steps of this comparative example were the same as in Example 7, the only difference being that in step (1), the 15 wt% PTFE suspension was replaced with 15 wt% polyperfluoroethylene propylene (FEP). As a result, the effect of improving the output performance of the friction nano-generator was not clear, and it was found to be lower than the power generation effect when PTFE was sprayed, as shown in Figure 24.

[0062] Comparative Example 3 The other steps of this comparative example were the same as in Example 7, the only difference being that the BTO particles with an average particle size of 100 nm in step (2) were replaced with titanium dioxide (TiO2), alumina (Al2O3), and polyvinylidene fluoride (PVDF) particles with an average particle size of 100 nm. As a result, as shown in Figure 25, we found that the power generation effect when doping with other nanoparticles was lower than the power generation effect when doping with BTO.

[0063] Comparative Example 4 The other steps in this comparative example were the same as in Example 7, the only difference being that PDMS (polydimethylsiloxane) in step (1) was replaced with PVA (polyvinyl alcohol). As a result, we found that the surface of the manufactured friction nano-generator exhibited hydrophilicity, as shown in Figure 26, making it prone to moisture adhesion in high-humidity environments and thus failing to improve moisture resistance.

[0064] Based on the above, the optimal embodiment is Example 7.

Claims

1. A method for manufacturing a droplet friction type nano-generator, Step 1 involves mixing PDMS with a curing agent to prepare a PDMS solution, mixing PTFE particles with ethanol, and performing ultrasonic dispersion to obtain a PTFE suspension. BaTiO ３ Step 2 involves mixing particles with a PDMS solution and performing ultrasonic dispersion to obtain a mixture. Step 3 involves knife coating the mixture onto the surface of the substrate (1), vacuuming, and drying to pre-cur it. Step 4 involves spraying a PTFE suspension onto the surface of the material obtained in step 3, drying and curing it to form a coating (2) on the surface of the substrate. A method for manufacturing a droplet friction type nanogenerator, characterized by including step 5, which involves arranging a top electrode (3) at an intermediate position on the surface of the object obtained in step 4 to obtain a droplet friction type nanogenerator.

2. The method for manufacturing a droplet friction type nano-generator according to claim 1, characterized in that, in step 1, the curing agent is one of dibutyl phthalate and dibutyltin dilaurate, and the mass ratio of the PDMS to the curing agent is 8 to 12:

1.

3. The method for producing a droplet friction type nano-generator according to claim 1, characterized in that, in step 1, the diameter of the PTFE particles is 2 to 10 μm, and the mass fraction of the PTFE particles in the suspension is 5 to 20 wt%.

4. In step 2, BaTiO ３ The average particle size of the particles is 50-500 nm, and the BaTiO in the mixture ３ The method for manufacturing a droplet friction type nanogenerator according to claim 1, characterized in that the mass fraction of the particles is 10 to 25 wt%.

5. The method for manufacturing a droplet friction type nano-generator according to claim 1, characterized in that the ultrasonic dispersion has a temperature of 10 to 30°C, a frequency of 20 to 60 kHz, and a power of 60 to 120 W.

6. The method for manufacturing a droplet friction type nano-generator according to claim 1, characterized in that in step 3, the substrate (1) is one of a PET thin film, a PVC thin film, or an ITO conductive thin film.

7. The method for manufacturing a droplet friction type nano-generator according to claim 1, characterized in that, in step 3, the pressure after vacuuming is 0.04 to 0.08 MPa, and the drying pre-curing is performed at a temperature of 55 to 65°C for a time of 10 to 15 min.

8. The method for manufacturing a droplet friction type nano-generator according to claim 1, characterized in that, in step 4, the drying and curing molding is performed at a temperature of 55 to 65°C for a duration of 2 to 4 hours, and the coating (2) has a thickness of 150 to 300 μm.

9. The method for manufacturing a droplet friction type nano-generator according to claim 1, characterized in that, in step 5, the top electrode (3) is one of a conductive copper wire, a conductive silver wire, and a tin-plated copper wire, with a diameter of 0.8 to 1.2 mm and a length of 10 to 30 mm.

10. The material comprises a base material (1), the surface of which a coating (2) is provided, and a top electrode (3) is positioned on the surface of the coating (2), and the coating (2) is made of BaTiO ３ A droplet friction type nanogenerator obtained in a method for manufacturing a droplet friction type nanogenerator according to any one of claims 1 to 9, characterized in that it is manufactured from PDMS and PTFE.

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