High-strength wear-resistant sliding type nanofiber friction nanogenerator and preparation method thereof
By combining interfacial crosslinking and solid lubricating nanofillers, the wear problem of nanofiber triboelectric nanogenerators in sliding mode is solved, improving their mechanical durability and electrical output stability, and expanding their application in wearable devices.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- DONGHUA UNIV
- Filing Date
- 2026-03-31
- Publication Date
- 2026-05-15
AI Technical Summary
Nanofiber triboelectric nanogenerators are susceptible to wear caused by high shear forces in sliding mode, resulting in poor mechanical durability and low electrical output stability, which limits their application in wearable devices.
A three-dimensional interconnected network structure of the positive electrode fiber membrane was constructed using an interface cross-linking enhancement strategy, and solid lubricating nanofillers were introduced into the negative electrode composite fiber membrane to form a low-friction lubrication interface.
It significantly improves the tensile strength and shear resistance of the fiber membrane, reduces the coefficient of friction, ensures the mechanical durability and electrical output stability of the device, and extends its service life.
Smart Images
Figure CN122052587A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of nanofiber triboelectric nanogenerator technology, and in particular to a high-strength, wear-resistant sliding nanofiber triboelectric nanogenerator and its preparation method. Background Technology
[0002] Nanofiber triboelectric nanogenerators, with their advantages of flexibility, light weight, excellent skin adhesion, and high mechanical-to-electrical energy conversion efficiency, can be seamlessly integrated into wearable devices such as clothing and human skin, showing broad application prospects in wearable energy harvesting and self-powered sensing. However, in actual wear, the device often experiences intense in-plane sliding friction caused by human movement, which easily induces wear, breakage, and interfacial delamination of the fiber material, leading to a sharp drop in power generation capacity and a significant decrease in the device's lifespan and electrical output stability. This has become a core bottleneck restricting its large-scale application.
[0003] Existing research on the modification of nanofiber triboelectric nanogenerators mainly focuses on performance optimization under the contact-separation mode, with little attention paid to the wear problem caused by high shear force under the sliding mode.
[0004] Therefore, there is an urgent need to develop a strategy to improve the wear resistance of nanofibers, so as to fundamentally overcome the bottleneck of nanofiber triboelectric nanogenerators in the application of wearable devices. Summary of the Invention
[0005] In view of this, the present invention provides a high-strength, wear-resistant sliding nanofiber triboelectric nanogenerator and its preparation method, so as to solve the problems of poor mechanical durability, severe wear in sliding mode, and low electrical output stability of existing nanofiber triboelectric nanogenerators.
[0006] To achieve the above objectives, the present invention adopts the following technical solution: A method for preparing a high-strength, wear-resistant, sliding nanofiber triboelectric nanogenerator includes the following steps: 1) The positive electrode material is mixed with the first solvent and electrospun to obtain a nanofiber membrane; the nanofiber membrane is treated with a thermoplastic elastomer solution to strengthen the interface and obtain a positive electrode composite fiber membrane. 2) The negative electrode material, solid lubricating nanofiller, and second solvent are mixed and electrospun to obtain a negative electrode composite fiber membrane with a low coefficient of friction. 3) The positive electrode composite fiber membrane is attached to the substrate with spaced electrodes, and the negative electrode composite fiber membrane is used as an independent friction layer to obtain a high-strength wear-resistant sliding nanofiber triboelectric nanogenerator. There is no specific order requirement for steps 1) and 2).
[0007] Preferably, the positive electrode material in step 1) includes one or more of polyamide 6, polyamide 66, polyvinyl alcohol, and thermoplastic polyurethane elastomer; The first solvent includes one or more of water, formic acid, acetic acid, N,N-dimethylformamide, N,N-dimethylacetamide, acetone, chloroform, tetrahydrofuran, and dichloromethane.
[0008] Preferably, the interface enhancement step in step 1) is as follows: The nanofiber membrane is immersed in a thermoplastic elastomer solution and then dried to complete the interface strengthening.
[0009] Preferably, the thermoplastic elastomer in the thermoplastic elastomer solution includes one or more of thermoplastic polyurethane, polyamide elastomers, and polyester elastomers; The mass concentration of the thermoplastic elastomer solution is 1~2 wt%; The soaking time is 4 to 8 hours.
[0010] Preferably, the negative electrode material in step 2) includes one or more of polyvinylidene fluoride, polyvinylidene fluoride-trifluoroethylene, polyvinylidene fluoride-hexafluoropropylene copolymer, fluororubber, polystyrene, polyvinyl chloride and polymethyl methacrylate; The solid lubricating nanofiller includes one or more of molybdenum disulfide, tungsten disulfide, graphite, graphene, and hexagonal boron nitride. The second solvent includes one or more of N,N-dimethylformamide, acetone, dichloromethane, tetrahydrofuran, chloroform, and N-methylpyrrolidone.
[0011] Preferably, the mass ratio of the negative electrode material to the solid lubricating nanofiller in step 2) is 10~15:0.05~0.45; The particle size of the solid lubricating nanofiller is 100~500 nm.
[0012] Preferably, the parameters of electrospinning in steps 1) and 2 are independent and include: spinning solution temperature 50~80℃, voltage 15~25 kV, and receiving distance 10~18 cm.
[0013] Preferably, the substrate of the spaced electrode in step 3) includes a PET substrate, and the electrode includes one or more of conductive fabric, copper foil and aluminum foil; The electrode spacing is 2~6 mm.
[0014] Another objective of this invention is to provide a high-strength, wear-resistant, sliding nanofiber triboelectric nanogenerator prepared by the above-described method.
[0015] As can be seen from the above technical solution, compared with the prior art, the present invention has the following beneficial effects: 1. This invention adopts an interface cross-linking enhancement strategy (interface strengthening) to construct a three-dimensional interconnected network structure at the fiber interface. After cross-linking treatment, the tensile strength of the positive electrode fiber membrane is significantly increased from 7.1 MPa to 13.3 MPa (an increase of 87.3%). This effectively suppresses fiber breakage and membrane delamination under sliding friction from the material structure level, giving the device excellent shear resistance and mechanical durability.
[0016] 2. This invention constructs a low-friction lubrication interface on the composite fiber membrane of the negative electrode through the co-spinning of solid lubricating nanofillers. This reduces the coefficient of friction by more than 40%, significantly reducing sliding wear and interface loss. From a triboelectric perspective, a lower coefficient of friction means reduced interfacial frictional resistance. On the one hand, this reduces mechanical wear on the fiber surface, preventing a decrease in the effective contact area of the friction layer due to material damage. On the other hand, a stable interfacial contact state helps maintain a uniform distribution and efficient transfer of triboelectric charges, thereby suppressing fluctuations and attenuation of the output electrical signal. This strategy overcomes the inherent defects of traditional liquid lubricants, such as easy loss and large output fluctuations, ensuring long-term stable electrical output performance of the device. Attached Figure Description
[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.
[0018] Figure 1 This is a surface morphology diagram of the positive electrode composite fiber membrane obtained in Example 2 of the present invention; Figure 2 This is a surface morphology diagram of the negative electrode composite fiber membrane obtained in Example 2 of the present invention; Figure 3 This is a comparison diagram of tensile stress-strain curves before and after interfacial crosslinking modification of the positive electrode composite fiber membrane in Example 2 of the present invention. Figure 4 This is a comparison chart of the friction coefficients before and after solid lubrication modification of the composite fiber membrane for the negative electrode in Example 2 of the present invention. Figure 5 A diagram illustrating the working mechanism of a sliding nanofiber triboelectric nanogenerator. Figure 6 This is a durability test diagram of the nanofiber triboelectric nanogenerator in Example 2 of the present invention; Figure 7This is a SEM image of the friction interface after 44,000 sliding cycles of the nanofiber triboelectric nanogenerator in Example 2 of the present invention. in, Figure 7 In this context, 'a' corresponds to the positive electrode composite fiber membrane. Figure 7 In this context, 'b' corresponds to the negative electrode composite fiber membrane. Detailed Implementation
[0019] This invention provides a method for preparing a high-strength, wear-resistant, sliding nanofiber triboelectric nanogenerator, comprising the following steps: 1) The positive electrode material is mixed with the first solvent and electrospun to obtain a nanofiber membrane; the nanofiber membrane is treated with a thermoplastic elastomer solution to strengthen the interface and obtain a positive electrode composite fiber membrane. 2) The negative electrode material, solid lubricating nanofiller, and second solvent are mixed and electrospun to obtain a negative electrode composite fiber membrane with a low coefficient of friction. 3) The positive electrode composite fiber membrane is attached to the substrate with spaced electrodes, and the negative electrode composite fiber membrane is used as an independent friction layer to obtain a high-strength wear-resistant sliding nanofiber triboelectric nanogenerator. There is no specific order requirement for steps 1) and 2).
[0020] In this invention, the positive electrode material mentioned in step 1) includes one or more of polyamide 6 (PA6), polyamide 66 (PA66), polyvinyl alcohol (PVA), and thermoplastic polyurethane elastomer (TPU); the first solvent includes one or more of water, formic acid, acetic acid, N,N-dimethylformamide, N,N-dimethylacetamide, acetone, chloroform, tetrahydrofuran, and dichloromethane.
[0021] In this invention, the mass concentration of the spinning solution used for electrospinning after mixing in step 1) is 7~26 wt%, specifically 8 wt%, 10 wt%, 12 wt%, 15 wt%, 18 wt%, 20 wt%, 22 wt%, and 25 wt%.
[0022] In this invention, the interface strengthening step in step 1) is as follows: the nanofiber membrane is immersed in a thermoplastic elastomer solution and then dried to complete the interface strengthening.
[0023] In this invention, the thermoplastic elastomer in the thermoplastic elastomer solution includes one or more of thermoplastic polyurethane (TPU), polyamide elastomer (TPAE), and polyester elastomer (TPEE).
[0024] In this invention, the mass concentration of the thermoplastic elastomer solution is 1~2 wt%, specifically 1.2 wt%, 1.4 wt%, 1.5 wt%, 1.6 wt%, or 1.8 wt%.
[0025] In this invention, the soaking time is 4 to 8 hours, specifically 4.5 hours, 5 hours, 5.5 hours, 6 hours, 6.5 hours, 7 hours, and 7.5 hours.
[0026] In this invention, the negative electrode material in step 2) includes one or more of polyvinylidene fluoride (PVDF), polyvinylidene fluoride-trifluoroethylene (PVDF-TrFE), polyvinylidene fluoride-hexafluoropropylene copolymer (PVDF-HFP), fluororubber (FKM), polystyrene (PS), polyvinyl chloride (PVC), and polymethyl methacrylate (PMMA); the solid lubricating nanofiller includes one or more of molybdenum disulfide, tungsten disulfide, graphite (Gr), graphene (GNS), and hexagonal boron nitride (h-BN); the second solvent includes one or more of N,N-dimethylformamide, acetone, dichloromethane, tetrahydrofuran, chloroform, and N-methylpyrrolidone.
[0027] In this invention, the mass ratio of the negative electrode material to the solid lubricating nanofiller in step 2) is 10~15:0.05~0.45, preferably 11~14:0.1~0.4, more preferably 12~13:0.2~0.3, and even more preferably 12.5:0.25.
[0028] In this invention, the mass concentration of the negative electrode material in the spinning solution used for electrospinning after mixing in step 2) is 7~26 wt%, specifically 8 wt%, 10 wt%, 12 wt%, 15 wt%, 18 wt%, 20 wt%, 22 wt%, and 25 wt%.
[0029] In this invention, the particle size of the solid lubricating nanofiller is 100~500 nm, specifically 150 nm, 200 nm, 250 nm, 300 nm, 350 nm, 400 nm, or 450 nm.
[0030] In this invention, the parameters for electrospinning in steps 1) and 2 are independent and include: spinning solution temperature of 50~80℃, specifically 55℃, 60℃, 65℃, 70℃, and 75℃; voltage of 15~25 kV, specifically 16 kV, 18kV, 20kV, 22kV, and 24kV; and receiving distance of 10~18 cm, specifically 12 cm, 14 cm, 15 cm, 16 cm, and 17 cm.
[0031] In this invention, the substrate of the spaced electrode in step 3) includes a PET substrate, and the electrode includes one or more of conductive fabric, copper foil and aluminum foil.
[0032] In this invention, the electrode spacing is 2 to 6 mm, specifically 3 mm, 4 mm, or 5 mm.
[0033] In this invention, the thickness of the positive electrode composite fiber membrane is preferably 0.12~0.2 mm, specifically 0.14 mm, 0.15 mm, 0.16 mm, or 0.18 mm; the thickness of the negative electrode composite fiber membrane is preferably 0.04~0.09 mm, specifically 0.05 mm, 0.06 mm, 0.07 mm, or 0.08 mm.
[0034] Another objective of this invention is to provide a high-strength, wear-resistant, sliding nanofiber triboelectric nanogenerator prepared by the above-described method.
[0035] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0036] Example 1
[0037] Experimental materials: The negative electrode material was fluororubber (FKM), the positive electrode material was nylon 6 (PA6) and thermoplastic polyurethane (TPU), and the solid lubricating nanofiller was graphite (Gr, Adamas, 82871L, 400 nm); the solvents included N,N-dimethylformamide (DMF), acetone and formic acid (containing dichloromethane as a cosolvent); the electrodes were made of conductive cloth, and the substrate was a PET film.
[0038] Preparation of positive electrode composite fiber membrane: 2.4 g of PA6 was weighed and added to 17.6 g of formic acid. The mixture was heated and stirred at 600 rpm at 70 °C until the PA6 was completely dissolved, thus preparing a PA6 electrospinning solution. Electrospinning was performed at an extrusion speed of 1 mL / h, an applied voltage of 21 kV, and a receiving distance of 17 cm to prepare a PA6 nanofiber membrane. This nanofiber membrane was immersed in a 1 wt% TPU solution (DMF solvent) for 4 hours, and then dried in a 90 °C oven for 8 hours to obtain a positive electrode composite fiber membrane.
[0039] Preparation of negative electrode composite fiber membrane (low coefficient of friction): Weigh 0.02 g of graphite (Gr) and add it to 18 g of DMF / acetone mixed solvent (mass ratio 1:1). Disperse the mixture ultrasonically for 1 hour to obtain a uniformly dispersed Gr suspension. Add 2 g of FKM to this suspension and heat and stir at 600 rpm at 60°C until the FKM is completely dissolved to obtain an FKM / Gr composite electrospinning solution. Spinning is performed using the same electrospinning parameters as in the first step to prepare an electronegative composite fiber membrane.
[0040] Assemble a triboelectric nanogenerator: Using PET as a substrate, two pieces of conductive cloth measuring 4 cm × 4 cm with a spacing of 2 mm are glued together as electrodes, and a 6 × 10 cm electrode is then attached to them. 2 A composite fiber membrane for the positive electrode with a thickness of 0.14 mm. The membrane has dimensions of 4×4 cm. 2 A negative electrode composite fiber membrane with a thickness of 0.05 mm is placed on top of an electropositive composite fiber membrane as an independent friction layer, so that the surfaces of the two friction layers are in contact with each other. A wire is led out from the conductive cloth electrode to connect the load, thus obtaining an all-fiber structure triboelectric nanogenerator suitable for sliding mode.
[0041] Example 2
[0042] Experimental materials: The negative electrode material was fluororubber (FKM) and polyvinylidene fluoride (PVDF), the positive electrode material was nylon 6 (PA6) and thermoplastic polyurethane (TPU), and the solid lubricating nanofiller was molybdenum disulfide (Macklin, M888682, 100nm); the solvents included N,N-dimethylformamide (DMF), acetone, formic acid and acetic acid; the electrode was made of conductive cloth, and the substrate was a PET film.
[0043] Preparation of positive electrode composite fiber membrane: 4 g of PA6 was weighed and added to 16 g of a formic acid-acetic acid mixed solvent (mass ratio 1:1). The mixture was heated and stirred at 600 rpm at 50 °C until the PA6 was completely dissolved, thus preparing a PA6 electrospinning solution. Electrospinning was performed at an extrusion speed of 1 mL / h, an applied voltage of 23 kV, and a receiving distance of 15 cm to prepare a PA6 nanofiber membrane. This nanofiber membrane was immersed in a 1.4 wt% TPU solution (solvent: DMF) for 4 hours, and then dried in an oven at 80 °C for 8 hours to obtain a positive electrode composite fiber membrane.
[0044] Preparation of negative electrode composite fiber membrane (low coefficient of friction): Weigh 0.02 g of MoS2 and add it to 18 g of a DMF / acetone mixed solvent (mass ratio 3:2). Disperse the mixture ultrasonically for 1 hour to obtain a uniformly dispersed MoS2 suspension. Add 2 g of FKM / PVDF (mass ratio 10:1) to this suspension and heat and stir at 600 rpm at 60°C until the FKM / PVDF is completely dissolved to obtain an FKM / PVDF / MoS2 composite electrospinning solution. Spinning is performed using the same electrospinning parameters as in the first step to prepare an electronegative composite fiber membrane.
[0045] Assemble a triboelectric nanogenerator: Using PET as a substrate, two pieces of conductive cloth measuring 4 cm × 4 cm with a spacing of 3 mm are glued together as electrodes, and a 6 × 10 cm electrode is then attached to them. 2 A composite fiber membrane for the positive electrode with a thickness of 0.16 mm. The membrane is 4×4 cm in size. 2 An electronegative composite fiber membrane with a thickness of 0.06 mm is placed on top of an electronegative composite fiber membrane, so that the surfaces of the two friction layers are in contact with each other. A wire is led out from the conductive cloth electrode to connect the load, thus obtaining an all-fiber triboelectric nanogenerator suitable for sliding mode.
[0046] The surface morphology of the positive electrode composite fiber membrane formed by soaking the above-mentioned PA6 nanofibers in TPU solution, i.e., the positive electrode composite fiber membrane based on interfacial crosslinking, is as follows: Figure 1 As shown. (Through) Figure 1 It can be seen that after TPU modification, obvious adhesion appears on the fiber surface and physical cross-linking points are formed between the fibers, indicating that the interfacial cross-linking structure has been successfully constructed. This structure is beneficial to improving the mechanical properties of the fiber membrane.
[0047] The surface morphology of the FKM / PVDF / MoS2 composite nanofiber membrane obtained by electrospinning after MoS2 doping, i.e., the electro-anode composite fiber membrane based on solid lubrication modification, is as follows: Figure 2 As shown. (Through) Figure 2 It can be seen that after MoS2 doping, the composite fiber has a regular morphology and uniform diameter, indicating that the introduction of MoS2 did not have an adverse effect on fiber forming and is uniformly distributed in the fiber matrix.
[0048] To investigate the effect of interfacial crosslinking modification on the mechanical properties of electropositive nanofiber membranes, the step of immersing in TPU solution during the preparation of the electropositive composite fiber membrane was omitted, resulting in a pure PA6 fiber membrane. Tensile tests were then conducted on both the pure PA6 fiber membrane (denoted as 1 - uncrosslinked pure fiber membrane) and the electropositive composite fiber membrane (denoted as 2 - crosslinked composite fiber membrane) using a universal testing machine. The resulting tensile stress-strain curves are shown below. Figure 3 As shown, through Figure 3It can be seen that the tensile strength of the pure PA6 fiber membrane is about 7.2 MPa, and the elongation at break is about 116%. After TPU modification, the tensile strength of the positive electrode composite fiber membrane is increased to 13.6 MPa, and the elongation at break is increased to 161.5%. The physical cross-linking network constructed by TPU effectively enhances the bonding force between fibers, achieving a simultaneous improvement in material strength and toughness.
[0049] To investigate the effect of solid lubrication modification on the friction coefficient of electronegative nanofiber membranes, only the addition of MoS2 was omitted during the preparation of the electronegative electrode composite fiber membrane, resulting in an FKM / PVDF membrane (referred to as the original unmodified membrane). The FKM / PVDF / MoS2 membrane with added MoS2 was referred to as the solid lubrication modified membrane. Two friction pairs were set up: the electronegative electrode composite fiber membrane with FKM / PVDF and the electronegative electrode composite fiber membrane with FKM / PVDF / MoS2. The dynamic and static friction coefficients were measured using a dynamic sliding friction test platform. The comparison of the friction coefficients of the electronegative nanofiber membranes before and after solid lubrication modification is shown in the figure below. Figure 4 As shown. (Through) Figure 4 It can be seen that the static friction coefficient is 1.33 and the dynamic friction coefficient is 1.13 without modification; after modification with MoS2, the static friction coefficient drops to 0.74, a reduction of 44.4%, and the dynamic friction coefficient drops to 0.66, a reduction of 41.6%. As a solid lubricant, MoS2 effectively reduces interfacial friction resistance, providing a guarantee for reducing sliding wear.
[0050] The working mechanism diagram of the sliding nanofiber triboelectric nanogenerator is shown below. Figure 5 As shown, through Figure 5 It can be seen that the electromechanical conversion mechanism of the all-fiber triboelectric nanogenerator in sliding mode is as follows: the sliding TENG generates a periodic potential difference through the relative sliding of the triboelectric material, which drives electrons to migrate in the external circuit to form an alternating current output.
[0051] A continuous sliding cycle test was conducted using a linear motor to drive the AF-S-TENG. The output voltage variation with the number of cycles was recorded using an oscilloscope to investigate the impact of different modification strategies on the long-term output stability of the device. The results of the all-fiber triboelectric nanogenerator output durability test (3 Hz, 0.5 N) in sliding mode are as follows: Figure 6 As shown, the results indicate that the unmodified friction pair (without interfacial crosslinking and solid lubrication) exhibits a sharp decline in output performance and complete structural damage after approximately 35 cycles; while the friction pair synergistically modified with interfacial crosslinking and solid lubrication shows no significant decline in output performance after 44,000 sliding cycles, remaining stable. The synergistic modification strategy significantly improves the sliding durability of the device.
[0052] The SEM image of the friction interface after 44,000 sliding cycles is shown below. Figure 7 As shown, Figure 7In this context, 'a' corresponds to the positive electrode composite fiber membrane. Figure 7 In this context, 'b' corresponds to the negative electrode composite fiber membrane. Through... Figure 7 It can be seen that the fiber structure on the surface of the positive electrode composite fiber membrane remains intact, with no obvious breakage or peeling, and the adhesion between fibers is good; the fiber structure on the surface of the negative electrode composite fiber membrane is also intact, with no obvious scratches or wear. These results confirm that the synergistic effect of TPU interfacial crosslinking and MoS2 solid lubrication effectively inhibits material transfer and interfacial wear, ensuring the long-term stable operation of the device.
[0053] Example 3
[0054] Experimental materials: The negative electrode material was polyvinylidene fluoride (PVDF) and polymethyl methacrylate (PMMA); the positive electrode material was polyvinyl alcohol (PVA) and polyamide elastomer (TPAE); the solid lubricating nanofiller was tungsten disulfide (WS2, Adamas, 17448CA, 100 nm); the solvents included N,N-dimethylacetamide (DMAc) and formic acid; the electrode was copper foil; and the substrate was PET film.
[0055] Preparation of positive electrode composite fiber membrane: 4 g of PVA was weighed and added to 16 g of formic acid. The mixture was heated and stirred at 75 °C at 600 rpm until the PVA was completely dissolved, thus preparing a PVA electrospinning solution. PVA nanofiber membranes were prepared by electrospinning under the conditions of an extrusion speed of 0.6 mL / h, an applied voltage of 23 kV, and a receiving distance of 17 cm. The fiber membrane was immersed in a 1.5 wt% TPAE solution (solvent: DMF) for 6 hours, and then dried in a 70 °C oven for 12 hours to obtain a positive electrode composite fiber membrane.
[0056] Preparation of negative electrode composite fiber membrane (low coefficient of friction): Weigh 0.04 g of WS2 and add it to 18.4 g of DMAc. Disperse the mixture ultrasonically for 1.5 hours to obtain a uniformly dispersed WS2 suspension. Add 1.6 g of PVDF / PMMA (mass ratio 9:1) to this suspension and heat and stir at 600 rpm at 60°C until the PVDF / PMMA is completely dissolved to obtain a PVDF / PMMA / WS2 composite electrospinning solution. Spinning is performed using the same electrospinning parameters as in the first step to prepare an electronegative composite fiber membrane.
[0057] Assemble a triboelectric nanogenerator: Using PET as a substrate, two 4 cm × 4 cm copper foils with a 3 mm gap were glued on as electrodes, and a 6 × 10 cm electrode was then attached to them. 2A composite fiber membrane for the positive electrode with a thickness of 0.16 mm. The membrane is 4×4 cm in size. 2 An electronegative composite fiber membrane with a thickness of 0.07 mm is placed on top of an electronegative composite fiber membrane as an independent friction layer, so that the surfaces of the two friction layers are in contact with each other. A wire is led out from the copper foil electrode to connect the load, thus obtaining an all-fiber structure triboelectric nanogenerator suitable for sliding mode.
[0058] Example 4
[0059] Experimental materials: The negative electrode material was polyvinyl chloride (PVC) and polymethyl methacrylate (PMMA), the positive electrode material was polyvinyl alcohol (PVA) and polyester elastomer (TPEE), and the solid lubricating nanofiller was hexagonal boron nitride (h-BN, Adamas, 10296AA, 500 nm); the solvents included tetrahydrofuran (THF) and deionized water; the electrode was made of copper foil, and the substrate was made of PET film.
[0060] Preparation of positive electrode composite fiber membrane: 3.2 g of PVA was weighed and added to 16.8 g of deionized water. The mixture was heated and stirred at 75 °C at 600 rpm until the PVA was completely dissolved, thus preparing a PVA electrospinning solution. PVA nanofiber membranes were prepared by electrospinning at an extrusion speed of 0.6 mL / h, an applied voltage of 20 kV, and a receiving distance of 15 cm. The fiber membrane was immersed in a 2 wt% TPEE solution (DMF solvent) for 6 hours, and then dried in an oven at 80 °C for 10 hours to obtain a positive electrode composite fiber membrane.
[0061] Preparation of negative electrode composite fiber membrane (low coefficient of friction): Weigh 0.05 g of h-BN and add it to 17.2 g of THF. Disperse the mixture ultrasonically for 0.5 hours to obtain a uniformly dispersed h-BN suspension. Add 2.8 g of PVC / PMMA (mass ratio 2:1) to this suspension and heat and stir at 600 rpm at 60°C until the PVC / PMMA is completely dissolved to obtain a PVC / PMMA / h-BN composite electrospinning solution. Spinning is performed using the same electrospinning parameters as in the first step to prepare an electronegative composite fiber membrane.
[0062] Assemble a triboelectric nanogenerator: Using PET as a substrate, two 4 cm × 4 cm copper foils with a 5 mm gap were glued on as electrodes, and a 6 × 10 cm electrode was then attached to them. 2 A composite fiber membrane for the positive electrode with a thickness of 0.18 mm. The membrane size is 4×4 cm. 2An electronegative composite fiber membrane with a thickness of 0.08 mm is used as an independent friction layer and placed on top of an electronegative composite fiber membrane, so that the surfaces of the two friction layers are in contact with each other. A wire is led out from the copper foil electrode to connect the load, thus obtaining an all-fiber structure triboelectric nanogenerator suitable for sliding mode.
[0063] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.
[0064] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.
Claims
1. A method for preparing a high-strength, wear-resistant, sliding nanofiber triboelectric nanogenerator, characterized in that, Includes the following steps: 1) The positive electrode material is mixed with the first solvent and electrospun to obtain a nanofiber membrane; the nanofiber membrane is treated with a thermoplastic elastomer solution to strengthen the interface and obtain a positive electrode composite fiber membrane. 2) The negative electrode material, solid lubricating nanofiller, and second solvent are mixed and electrospun to obtain a negative electrode composite fiber membrane with a low coefficient of friction. 3) The positive electrode composite fiber membrane is attached to the substrate with spaced electrodes, and the negative electrode composite fiber membrane is used as an independent friction layer to obtain a high-strength wear-resistant sliding nanofiber triboelectric nanogenerator. There is no specific order requirement for steps 1) and 2).
2. The method for preparing a high-strength, wear-resistant, sliding nanofiber triboelectric nanogenerator according to claim 1, characterized in that, The positive electrode material mentioned in step 1) includes one or more of polyamide 6, polyamide 66, polyvinyl alcohol, and thermoplastic polyurethane elastomer; The first solvent includes one or more of water, formic acid, acetic acid, N,N-dimethylformamide, N,N-dimethylacetamide, acetone, chloroform, tetrahydrofuran, and dichloromethane.
3. The method for preparing a high-strength, wear-resistant, sliding nanofiber triboelectric nanogenerator according to claim 1 or 2, characterized in that, The interface enhancement steps described in step 1) are as follows: The nanofiber membrane is immersed in a thermoplastic elastomer solution and then dried to complete the interface strengthening.
4. The method for preparing a high-strength, wear-resistant, sliding nanofiber triboelectric nanogenerator according to claim 3, characterized in that, The thermoplastic elastomer in the thermoplastic elastomer solution includes one or more of thermoplastic polyurethane, polyamide elastomers, and polyester elastomers; The mass concentration of the thermoplastic elastomer solution is 1~2 wt%; The soaking time is 4 to 8 hours.
5. The method for preparing a high-strength, wear-resistant, sliding nanofiber triboelectric nanogenerator according to claim 4, characterized in that, The negative electrode material mentioned in step 2) includes one or more of the following: polyvinylidene fluoride, polyvinylidene fluoride-trifluoroethylene, polyvinylidene fluoride-hexafluoropropylene copolymer, fluororubber, polystyrene, polyvinyl chloride and polymethyl methacrylate; The solid lubricating nanofiller includes one or more of molybdenum disulfide, tungsten disulfide, graphite, graphene, and hexagonal boron nitride. The second solvent includes one or more of N,N-dimethylformamide, acetone, dichloromethane, tetrahydrofuran, chloroform, and N-methylpyrrolidone.
6. The method for preparing a high-strength, wear-resistant, sliding nanofiber triboelectric nanogenerator according to claim 5, characterized in that, In step 2), the mass ratio of the negative electrode material to the solid lubricating nanofiller is 10~15:0.05~0.45; The particle size of the solid lubricating nanofiller is 100~500 nm.
7. The method for preparing a high-strength, wear-resistant, sliding nanofiber triboelectric nanogenerator according to claim 6, characterized in that, The parameters for electrospinning in steps 1) and 2 are independent and include: spinning solution temperature 50~80℃, voltage 15~25 kV, and receiving distance 10~18 cm.
8. A method for preparing a high-strength, wear-resistant, sliding nanofiber triboelectric nanogenerator according to any one of claims 5 to 7, characterized in that, The substrate of the spaced electrode mentioned in step 3) includes a PET substrate, and the electrode includes one or more of conductive fabric, copper foil and aluminum foil; The electrode spacing is 2~6 mm.
9. A high-strength, wear-resistant sliding nanofiber triboelectric nanogenerator prepared by the preparation method according to any one of claims 1 to 8.