Friction nano-generator based on ternary nanocrystal / polymer composite fiber film and preparation method of friction nano-generator
The AgBiS2/PVDF-HFP composite fiber film and TPU film were prepared by electrospinning technology to form a friction nanogenerator with a dual-electrode structure, which solved the problem of low energy collection efficiency of TENG and achieved efficient and stable electrical energy output, which was suitable for wearable devices.
Patent Information
- Application Number
- CN202510458693.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-14
- Publication Date
- 2025-07-11
AI Technical Summary
There is room for improvement in the energy harvesting efficiency of existing friction nanogenerators (TENGs), especially in the optimization of electrode materials and microstructures. The limited life of traditional batteries and environmental impacts have become bottlenecks that restrict their widespread application.
Electrospinning technology was used to prepare AgBiS2/PVDF-HFP composite fiber film as a negative friction layer, and combined with the TPU film to form a friction nanogenerator with a dual-electrode structure, which improved charge transfer efficiency and flexibility by optimizing material combination.
It significantly improves the output performance of friction nanogenerators, with a peak output voltage increase of 30%, a peak current increase of about 100%, and maintains good repeatability and stability. It is suitable for wearable devices.
Smart Images
Figure CN120301236A_ABST
Abstract
Description
Technical Field
[0001] The present invention belongs to the technical field of energy harvesting and flexible electronics, and particularly relates to a triboelectric nanogenerator (TENG) based on ternary nanocrystal / polymer composite fiber film and a preparation method thereof. Background Art
[0002] The problem of energy shortage is a global research topic, which greatly affects the quality of our daily life and the industrial development of modern society. The beginning of the Second Industrial Revolution marked the start of humanity's exploration of the practical value of electricity, and electrical energy has always been an important energy source applied in our production and life. With the continuous development and progress of technology, electronic devices are increasingly widely used in production and life, and electronic devices also show a development trend of miniaturization, lightweight, and portability. Therefore, a sustainable power solution is needed to meet the upcoming needs of smart life, while traditional batteries face challenges due to their limited lifespan, environmental impact, and regular replacement. Therefore, as an innovative energy harvesting technology, TENG has great research significance and prospects.
[0003] TENG is a cutting-edge energy harvesting technology, the core of which is to utilize the contact and separation process between materials to stimulate charge generation, and then efficiently convert mechanical energy into electrical energy. The working principle of TENG is based on the close combination of the friction effect and the electrostatic induction effect. When two different materials come into contact and then separate, a voltage difference will be instantly formed, driving electrons to flow in the external circuit to achieve a charge balance state.
[0004] In the research of TENG, how to improve the energy harvesting efficiency of TENG is the top priority. To address this issue, optimizing electrode materials and material microstructure, selecting materials with a large difference in dielectric constant, and surface-modifying materials through microfabrication or chemical methods are important research directions. Poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) is a piezoelectric material with good piezoelectric properties, having advantages such as high piezoelectric coefficient, good biocompatibility, wide frequency response, high flexibility, and easy processing. Among them, the β-phase PVDF-HFP with a polar crystal structure can exhibit strong piezoelectricity. Therefore, increasing the β-phase content of PVDF-HFP is an important means to enhance its piezoelectric properties. In addition, using a conductive medium doped with a polymer as the negative friction electrode material is also an important means to improve performance. The doped conductive medium usually has high conductivity, which is conducive to more efficient charge transfer in TENG. At the same time, its combination with the polymer matrix can optimize the surface morphology and chemical properties of the composite fiber film, thereby enhancing the charge transfer efficiency between it and the positive friction layer thermoplastic polyurethane (TPU) film. Silver bismuth sulfide (AgBiS2) has inevitable surface defects during the preparation process, which can introduce electron traps into the negative friction layer, facilitating the enhancement of the charge capture ability of the negative friction layer and enhancing its output electrical performance. In addition, the polymer matrix endows the composite fiber film with good flexibility and processability, enabling it to adapt to various complex shapes and curved surfaces, thus increasing the application range and wearability of TENG. At the same time, the composite fiber film also has good durability and can still maintain a stable output after repeated application of the same pressure multiple times. Moreover, the stability of AgBiS2 nanocrystals enables the composite fiber film to maintain stable performance during long-term use and is not prone to performance degradation. Summary of the Invention
[0005] The object of the present invention is to provide a triboelectric nanogenerator based on a ternary nanocrystal / polymer (AgBiS2 / PVDF-HFP) composite fiber film and a preparation method thereof.
[0006] The present invention prepares a composite fiber structure based on AgBiS2 / PVDF-HFP through electrospinning technology and fabricates a flexible triboelectric nanogenerator. The results show that the triboelectric nanogenerator prepared in the present invention uses a TPU film as the positive friction layer, thus having good wearability. Doping AgBiS2 in PVDF-HFP significantly increases the output performance of the triboelectric nanogenerator. Under the output test of a pressure of 10 N, the peak output voltage of the triboelectric nanogenerator with a doping concentration of 5 wt% can reach 200 V, with a 30% improvement in performance compared to that before doping. In addition, the triboelectric nanogenerator based on the AgBiS2 / PVDF-HFP composite fiber film has good repeatability and a fast response recovery time, and all performance indicators can remain stable during long-term use.
[0007] The preparation method of a triboelectric nanogenerator based on a ternary nanocrystal / polymer (AgBiS2 / PVDF-HFP) composite fiber film according to the present invention is as follows:
[0008] (1) Prepare AgBiS2 solid particles
[0009] First, 0.7 - 0.9 mmol of silver acetate (Ag(OAc)) and 0.9 - 1.1 mmol of bismuth acetate (Bi(OAc)3) are mixed in 4 - 8 mL of oleic acid, and stirred at 90 - 110 °C for 0.5 - 2.0 h under nitrogen protection to obtain a precursor solution. Second, 1.0 - 1.2 mmol of sulfur is added to 5 - 6 mL of oleylamine, stirred for 4 - 6 min, and then mixed with the precursor solution. After cooling to room temperature, acetone is added for centrifugation, with a centrifugation rate of 8000 - 12000 rpm and a centrifugation time of 15 - 30 minutes. Then, the obtained AgBiS2 nanoparticles are dispersed in toluene, and acetone is added for centrifugation, with a centrifugation rate of 10000 - 15000 rpm and a centrifugation time of 8 - 15 minutes. The operation of "dispersing in toluene - adding acetone for centrifugation" is repeated 2 - 3 times to obtain 130 - 200 mg of AgBiS2 solid particles;
[0010] (2) Prepare the AgBiS2 / PVDF-HFP composite fiber film
[0011] First, prepare a mixed solution with a volume ratio of 1:1 of N,N-dimethylformamide (DMF) and acetone (purchased from Jilin Regal Chemical Co., Ltd.). Then, add the AgBiS2 solid particles prepared in step (1) to 8 - 10 g of the mixed solution, and stir at room temperature for 4 - 6 h to evenly distribute the monolayer AgBiS2. Next, add PVDF-HFP (purchased from Sigma-Aldrich (Shanghai) Co., Ltd.) to the mixed solution and stir overnight at room temperature. The mass dosage of AgBiS2 is 3 - 15% of the sum of the dosages of AgBiS2 and PVDF-HFP. Load the obtained AgBiS2 / PVDF-HFP mixed solution into a 10 mL metal syringe with a 19-gauge metal needle, and then place it into an electrospinning device (consisting of a high-voltage electrostatic device, a metal syringe, and a receiving device). Set the electrospinning voltage to 15 - 20 kV, the distance between the electrospinning needle and the collecting device to 12 - 18 cm, the solution flow rate to 0.5 - 1.0 mL / h, the lateral movement distance of the collecting device to 75 - 85 mm, and the longitudinal distance to 150 - 170 mm. After electrospinning for 4 - 6 h, remove the obtained AgBiS2 / PVDF-HFP composite fiber film from the collecting device. The thickness of the film is 30 - 50 μm;
[0012] (3) Prepare the TPU fiber film
[0013] First, weigh 3 - 5 g of DMF and 3 - 5 g of tetrahydrofuran (THF) to obtain a mixed solution. Add 1.5 - 3.0 g of TPU particles (purchased from Sinopharm Chemical Reagent Co., Ltd. (Shanghai)) to this mixed solution and stir overnight at room temperature. Load the obtained TPU solution into a 10 mL metal syringe with a 19-gauge metal needle, and then place it into the electrospinning device. Set the electrospinning voltage to 15 - 20 kV, the distance between the electrospinning needle and the collecting device to 12 - 18 cm, the solution flow rate to 0.3 - 0.5 mL / h, the lateral movement distance of the collecting device to 75 - 85 mm, and the longitudinal movement distance to 150 - 170 mm. After electrospinning for 3 - 5 h, remove the obtained TPU fiber film from the collecting device. The thickness of the film is 20 - 100 μm;
[0014] (4) Assemble the triboelectric nanogenerator
[0015] First, prepare two pieces of flexible conductive copper tape with a size of 3 cm × 3 cm (thickness 30 - 50 μm), weld two copper wires with a diameter of 0.15 mm at the tail ends of the flexible conductive copper tape, one piece of AgBiS2 / PVDF-HFP composite fiber film with a size of 5 cm × 5 cm, one piece of TPU fiber film with a size of 5 cm × 5 cm, two pieces of polyethylene terephthalate (PET) film with a size of 5 cm × 5 cm (thickness 75 - 125 μm), and two pieces of medical waterproof polyurethane (PU) film with a size of 5 cm × 5 cm (thickness 50 - 100 μm); then, stick the two pieces of conductive copper tape on the central outer surfaces of the two pieces of PET film respectively, and then place the AgBiS2 / PVDF-HFP composite fiber film and the TPU fiber film on the inner surfaces of the two pieces of PET film respectively. The AgBiS2 / PVDF-HFP composite fiber film and the TPU fiber film are separated by two insulating gaskets (thickness 0.1 - 0.3 mm) with a distance of 2 - 4 cm between them. The AgBiS2 / PVDF-HFP fiber film is used as the negative friction layer of the TENG, and the TPU fiber film is used as the positive friction layer of the TENG; finally, use the medical waterproof PU film to encapsulate the conductive copper tape, PET film, AgBiS2 / PVDF-HFP composite fiber film and TPU fiber film, so as to obtain a triboelectric nanogenerator based on AgBiS2 / PVDF-HFP composite fiber film with a double-electrode structure.
[0016] The triboelectric nanogenerator based on AgBiS2 / PVDF-HFP composite fiber film described in the present invention is prepared by the above method.
[0017] The advantages of the present invention are as follows:
[0018] (1) The composite fiber film of AgBiS2 / PVDF-HFP is prepared by electrospinning for making the electrode of the triboelectric nanogenerator and combined with the TPU film to make it have thinness, lightness and high flexibility, and the manufacturing process is simple and the cost is low.
[0019] (2) The triboelectric nanogenerator of the ternary nanocrystal / polymer composite fiber film prepared by the present invention has excellent output performance, and the peak value of the current generated instantaneously can reach 2 μA. Description of the Drawings
[0020] Figure 1 : Transmission electron microscope (TEM) image of ternary nanocrystal AgBiS2;
[0021] Figure 2 : Scanning electron microscope (SEM) morphology images of AgBiS2 / PVDF-HFP composite fiber films prepared under the doping concentration of Example 1 (a) and the doping concentration of Example 2 (b);
[0022] Figure 3 : X-ray diffraction analysis (XRD) characterization results and crystal phase distribution diagrams of the AgBiS2 / PVDF-HFP composite fiber films prepared in the comparative example and Examples 1-2;
[0023] Figure 4 : Schematic diagram of the TENG structure prepared based on the AgBiS2 / PVDF-HFP composite fiber film;
[0024] Figure 5 : Open-circuit voltage output response curves of the TENGs prepared in the comparative example and Examples 1-2 under a pressure of 10 N (a) and open-circuit voltage output response curves of the TENG prepared in Example 1 under different pressures (b);
[0025] Figure 6 : Current output response curves of the TENGs prepared in the comparative example and Examples 1-2 under a pressure of 10 N (a); Charge accumulation curves of the TENGs prepared in the comparative example and Examples 1-2 under a pressure of 10 N (b);
[0026] Figure 7 : Output cycle test curve of the TENG prepared in Example 1 with a 10 N pressure applied cyclically 8000 times;
[0027] Figure 8 : Time and voltage curves required to charge different-sized capacitors to 2.5 V using the TENG prepared in Example 1.
[0028] As Figure 1 shown, it was proven by TEM image characterization that AgBiS2 was successfully synthesized, could be uniformly distributed in toluene, and had a diameter of about 4.72 ± 1.02 nm.
[0029] As Figure 2 shown, at the doping concentrations of Example 1 (a) and Example 2 (b), the fiber films were evenly distributed and no obvious adhesion occurred, indicating that the method of using AgBiS2 and PVDF-HFP for mixed spinning to prepare the negative friction electrode was feasible, and the addition of AgBiS2 would not affect the morphology of PVDF-HFP fibers.
[0030] As Figure 3 shown, XRD characterization was performed on the three fiber films. PVDF-based compounds mainly had three crystal phases, α, β, and γ, with the first two being dominant. The triboelectric performance of PVDF-HFP mainly depended on the polar crystal phase β-phase. The method of electrospinning and doping AgBiS2 could cause a part of the non-polar crystal phase α-phase to undergo rotational polarization of the polymer carbon chain under the action of high voltage, thus converting into the β-phase and enhancing the electron adsorption ability. By analyzing the characterization results, the α / β measured in Example 1 was greater than that of the comparative example and Example 2. It was speculated that the output performance of the TENG composed of it should be higher than the other two.
[0031] As Figure 4 shown, the names of each part are: waterproof PU film 1, flexible conductive tape 2, AgBiS2 / PVDF-HFP composite fiber film 3, insulating gasket 4, and TPU fiber film 5. The AgBiS2 / PVDF-HFP composite fiber film 3 and the TPU fiber film 5 are separated by two insulating gaskets 4. The distance between the two insulating gaskets 4 is 3 cm. The length of each insulating gasket 4 is 1 cm, the width is 0.92 mm, and the thickness is 0.25 mm. Finally, the entire device is encapsulated up and down with a medical waterproof PU film 1 to form a sealed structure. This structural design ensures that the positive and negative friction electrodes are separated when the device is not subjected to external forces, and the two electrodes approach each other and finally come into contact when squeezed. At the same time, it can significantly reduce the influence of external conditions such as sweat and skin conditions on the output performance.
[0032] As Figure 5 shown, under a pressure of 10 N, the open-circuit voltage output of the TENG prepared in the comparative example is 131.2 V, while the open-circuit voltage outputs of the TENGs prepared in Experimental Example 1 and Experimental Example 2 under the same conditions reach 186.1 V and 159.3 V respectively, an increase of 41.8% and 21.4% respectively. Therefore, Experimental Example 1 was selected as the optimized doping concentration for further testing. When the pressure gradually increases from 10 N to 200 N, the output open-circuit voltage value also increases, reaching a maximum of 242.2 V.
[0033] As Figure 6 shown, under a pressure of 10 N, the peak-to-peak value of the current output by the TENG prepared in the comparative example is 1.5 μA, while the peak-to-peak values of the current outputs of the TENGs prepared in Experimental Example 1 and Experimental Example 2 reach 3.3 μA and 2.5 μA respectively. Further measuring the charge accumulated on its surface area, the TENG prepared in the comparative example accumulates 40.9 nC of charge per single time, the TENG prepared in Experimental Example 1 accumulates 71.3 nC of charge per single time, and the TENG prepared in Experimental Example 2 accumulates 55.1 nC of charge per single time.
[0034] As Figure 7 shown, after 8000 times of output stability testing on the TENG assembled in Experimental Example 1, it is found that the output voltage of the device shows a small amount of attenuation, but it can still maintain the output stability and has good durability.
[0035] As Figure 8 shown, by using an external bridge rectifier circuit and pressing the TENG to charge capacitors of different sizes, the TENG prepared in Example 1 can charge a 14.7 μF capacitor to 2.5 V within 180 s, and it only takes 15 s to charge a 0.47 μF capacitor to 2.5 V, showing good charge accumulation ability. Detailed implementation mode
[0036] Comparative example:
[0037] A triboelectric nanogenerator based on a PVDF-HFP fiber film and a preparation method thereof, the steps are as follows:
[0038] (1) Preparation of PVDF-HFP fiber film: First, prepare a mixed solution with a volume ratio of 1:1 of N,N-dimethylformamide (DMF) and acetone (purchased from Jilin Ruiji Chemical Co., Ltd.), and then add 1.14 g of PVDF-HFP (purchased from Sigma-Aldrich (Shanghai) Co., Ltd.) to 8.2 g of the mixed solution, and stir overnight at room temperature; then put the obtained solution into a 10 mL syringe equipped with a No. 19 metal needle, and then put it into an electrospinning device. Set the electrospinning voltage to 18 kV, the distance between the needle head and the collection device to 15 cm, the solution flow rate to 0.8 mL / h, the lateral movement distance of the collection device to 80 mm, and the longitudinal movement distance to 160 mm. After electrospinning for 5 h, take the obtained PVDF-HFP fiber film off the collection device, and the film thickness is 80 μm;
[0039] (2) Preparation of TPU fiber film: Weigh 4 g of DMF and 4 g of THF to obtain a mixed solution, add 2 g of TPU to the mixed solution, and then stir overnight at room temperature. Put the obtained TPU solution into a 10 mL syringe equipped with a No. 19 metal needle, and then put it into an electrospinning device. Set the electrospinning voltage to 17 kV, the distance between the electrospinning needle head and the collection device to 15 cm, the solution flow rate to 0.4 mL / h, the lateral movement distance of the collection device to 80 mm, and the longitudinal distance to 160 mm. After electrospinning for 4 h, take the obtained TPU fiber film off the collection device, and the film thickness is 50 μm;
[0040] (3) Assembly of TENG: First, prepare 2 pieces of flexible conductive copper tape with a size of 3 cm × 3 cm (thickness: 50 μm), and weld two copper wires with a diameter of 0.15 mm at the tail ends of the flexible conductive copper tape, 1 piece of PVDF-HFP fiber film with a size of 5 cm × 5 cm, 1 piece of TPU fiber film with a size of 5 cm × 5 cm, 2 pieces of PET film with a size of 5 cm × 5 cm (thickness: 100 μm), and 2 pieces of medical waterproof PU film with a size of 5 cm × 5 cm (thickness: 100 μm); Then, stick the 2 pieces of conductive copper tape on the central outer surfaces of the two PET films respectively, and then place the PVDF-HFP fiber film and the TPU fiber film on the inner surfaces of the two PET films respectively. The PVDF-HFP fiber film and the TPU fiber film are separated by two insulating gaskets 4. The distance between the two insulating gaskets 4 is 3 cm. The length of each insulating gasket 4 is 1 cm, the width is 0.92 mm, and the thickness is 0.25 mm. The PVDF-HFP fiber film is used as the negative friction layer of the TENG, and the TPU fiber film is used as the positive friction layer of the TENG; Finally, use the medical waterproof PU film to encapsulate the conductive copper tape, the PET film, the PVDF-HFP fiber film and the TPU fiber film, so as to obtain a triboelectric nanogenerator based on PVDF-HFP fiber film with a double-electrode structure.
[0041] Example 1:
[0042] A triboelectric nanogenerator based on AgBiS2 / PVDF-HFP composite fiber film and its preparation method are as follows:
[0043] (1) Preparation of AgBiS2: First, mix 0.8 mmol Ag(OAc) and 1.0 mmol Bi(OAc)3 in 5.5 mL oleic acid. Degas the mixture and fill the bottle with N2. Then, stir at 100 °C for 1 h under nitrogen protection to obtain a precursor solution; Second, add 1.0 mmol sulfur to 5 mL oleylamine, stir for 5 min and then mix it with the precursor solution. After cooling to room temperature, add acetone for centrifugation, the centrifugation rate is 10,000 rpm, and the centrifugation time is 20 minutes; Then disperse the obtained AgBiS2 nanoparticles in toluene, add acetone for centrifugation, the centrifugation rate is 12,000 rpm, and the centrifugation time is 10 minutes; Repeat the operation of "disperse in toluene - add acetone for centrifugation" 2 times to obtain 165 mg of AgBiS2 solid particles;
[0044] (2) Preparation of AgBiS2 / PVDF-HFP composite fiber film: Prepare a mixed solution with a volume ratio of DMF to acetone of 1:1. Then add 0.05 g of AgBiS2 solid particles to 8.2 g of the prepared mixed solution and stir at room temperature for 5 h to evenly distribute the monolayer AgBiS2. Then add 0.95 g of PVDF-HFP (the mass dosage of AgBiS2 is 5% of the sum of the dosages of AgBiS2 and PVDF-HFP) to the mixed solution and stir overnight at room temperature. Load the obtained AgBiS2 / PVDF-HFP mixed solution into a 10 mL syringe equipped with a No. 19 metal needle, and then place it into an electrospinning device. Set the electrospinning voltage to 18 kV, the distance between the needle and the collection device to 15 cm, the solution flow rate to 0.8 mL / h, the lateral movement distance of the collection device to 80 mm, and the longitudinal distance to 160 mm. After electrospinning for 5 h, remove the obtained AgBiS2 / PVDF-HFP composite fiber film from the collection device. The film thickness is 40 μm;
[0045] (3) Preparation of TPU fiber film: Weigh 4 g of DMF and 4 g of THF to obtain a mixed solution. Add 2 g of TPU to this mixed solution and then stir overnight at room temperature. Load the obtained TPU solution into a 10 mL syringe equipped with a No. 19 metal needle, and then place it into an electrospinning device. Set the electrospinning voltage to 17 kV, the distance between the electrospinning needle and the collection device to 15 cm, the solution flow rate to 0.4 mL / h, the lateral movement distance of the collection device to 80 mm, and the longitudinal distance to 160 mm. After electrospinning for 4 h, remove the obtained TPU fiber film from the collection device. The film thickness is 50 μm;
[0046] (4) Assembly of TENG: First, prepare 2 pieces of flexible conductive copper tape sized 3 cm × 3 cm (with a thickness of 50 μm), and weld two copper wires with a diameter of 0.15 mm at the tail ends of the flexible conductive copper tape, 1 piece of AgBiS2 / PVDF-HFP composite fiber film sized 5 cm × 5 cm, 1 piece of TPU fiber film sized 5 cm × 5 cm, 2 pieces of PET film (with a thickness of 100 μm) sized 5 cm × 5 cm, and 2 pieces of medical waterproof PU film (with a thickness of 100 μm) sized 5 cm × 5 cm; then, stick the 2 pieces of conductive copper tape on the central outer surfaces of the two PET films respectively, and then place the AgBiS2 / PVDF-HFP composite fiber film and the TPU fiber film on the inner surfaces of the PET films respectively. The AgBiS2 / PVDF-HFP composite fiber film and the TPU fiber film are separated by two insulating gaskets 4, and the distance between the two insulating gaskets 4 is 3 cm. Each insulating gasket 4 has a length of 1 cm, a width of 0.92 mm, and a thickness of 0.25 mm. The AgBiS2 / PVDF-HFP fiber film is used as the negative friction layer of the TENG, and the TPU fiber film is used as the positive friction layer of the TENG; finally, use the medical waterproof PU film to encapsulate the conductive copper tape, the PET film, the AgBiS2 / PVDF-HFP composite fiber film and the TPU fiber film, so as to obtain a triboelectric nanogenerator based on the AgBiS2 / PVDF-HFP composite fiber film with a double-electrode structure.
[0047] Example 2:
[0048] A triboelectric nanogenerator based on an AgBiS2 / PVDF-HFP composite fiber film and a preparation method thereof, the steps are as follows:
[0049] (1) Preparation of AgBiS2: First, mix 0.8 mmol of Ag(OAc) and 1.0 mmol of Bi(OAc)3 in 5.5 mL of oleic acid. Degas the mixture and fill the bottle with N2. Then, stir at 100 °C for 1 h under nitrogen protection to obtain a precursor solution; secondly, add 1.0 mmol of sulfur to 5 mL of oleylamine, stir for 5 min and then mix it with the precursor solution. After cooling to room temperature, add acetone for centrifugation, with a centrifugation rate of 10,000 rpm and a centrifugation time of 20 minutes; then disperse the obtained AgBiS2 nanoparticles in toluene, add acetone for centrifugation, with a centrifugation rate of 12,000 rpm and a centrifugation time of 10 minutes; repeat the operation of "disperse in toluene - add acetone for centrifugation" 2 times to obtain 165 mg of AgBiS2 solid particles;
[0050] (2) Preparation of AgBiS2 / PVDF-HFP composite fiber film: Prepare a mixed solution with a volume ratio of DMF to acetone of 1:1. Then add 0.1 g of AgBiS2 solid particles to 8.2 g of the prepared mixed solution and stir at room temperature for 5 h to uniformly distribute monolayer AgBiS2. Then add 0.9 g of PVDF-HFP (the mass dosage of AgBiS2 is 10% of the sum of the dosages of AgBiS2 and PVDF-HFP) to the mixed solution and stir overnight at room temperature. Load the obtained AgBiS2 / PVDF-HFP mixed solution into a 10 mL syringe equipped with a No. 19 metal needle, and then place it into an electrospinning device. Set the electrospinning voltage to 18 kV, the distance between the needle and the collection device to 15 cm, the solution flow rate to 0.8 mL / h, the lateral movement distance of the collection device to 80 mm, and the longitudinal distance to 160 mm. After electrospinning for 5 h, remove the obtained AgBiS2 / PVDF-HFP composite fiber film from the collection device. The film thickness is 40 μm;
[0051] (3) Preparation of TPU fiber film: Weigh 4 g of DMF and 4 g of THF to obtain a mixed solution. Add 2 g of TPU to this mixed solution and then stir overnight at room temperature. Load the obtained TPU solution into a 10 mL syringe equipped with a No. 19 metal needle, and then place it into an electrospinning device. Set the electrospinning voltage to 17 kV, the distance between the electrospinning needle and the collection device to 15 cm, the solution flow rate to 0.4 mL / h, the lateral movement distance of the collection device to 80 mm, and the longitudinal distance to 160 mm. After electrospinning for 4 h, remove the obtained TPU fiber film from the collection device. The film thickness is 50 μm;
[0052] (4) Assembly of TENG: First, prepare 2 pieces of flexible conductive copper tape sized 3 cm × 3 cm (with a thickness of 50 μm), and weld two copper wires with a diameter of 0.15 mm at the tail ends of the flexible conductive copper tape, 1 piece of AgBiS2 / PVDF-HFP composite fiber film sized 5 cm × 5 cm, 1 piece of TPU fiber film sized 5 cm × 5 cm, 2 pieces of PET film (with a thickness of 100 μm) sized 5 cm × 5 cm, and 2 pieces of medical waterproof PU film (with a thickness of 100 μm) sized 5 cm × 5 cm; then, stick the 2 pieces of conductive copper tape to the centers of the outer surfaces of the two PET films respectively, and then place the AgBiS2 / PVDF-HFP composite fiber film and the TPU fiber film on the inner surfaces of the PET films respectively. The AgBiS2 / PVDF-HFP composite fiber film and the TPU fiber film are separated by two insulating gaskets 4, and the distance between the two insulating gaskets 4 is 3 cm. The length of each insulating gasket 4 is 1 cm, the width is 0.92 mm, and the thickness is 0.25 mm. Take the AgBiS2 / PVDF-HFP fiber film as the negative friction layer of the TENG and the TPU fiber film as the positive friction layer of the TENG; finally, use the medical waterproof PU film to encapsulate the conductive copper tape, the PET film, the AgBiS2 / PVDF-HFP composite fiber film and the TPU fiber film, so as to obtain a triboelectric nanogenerator based on the AgBiS2 / PVDF-HFP composite fiber film with a double-electrode structure.
Claims
1. A preparation method of a triboelectric nanogenerator based on a ternary nanocrystal / polymer composite fiber film, the steps are as follows: (1) Prepare AgBiS2 solid particles First, mix 0.7 - 0.9 mmol of silver acetate and 0.9 - 1.1 mmol of bismuth acetate in 4 - 8 mL of oleic acid, stir at 90 - 110 °C for 0.5 - 2.0 h under nitrogen protection to obtain a precursor solution; second, add 1.0 - 1.2 mmol of sulfur to 5 - 6 mL of oleylamine, stir for 4 - 6 min and then mix it with the precursor solution. After cooling to room temperature, add acetone for centrifugation, the centrifugation rate is 8000 - 12000 rpm, and the centrifugation time is 15 - 30 minutes; then disperse the obtained AgBiS2 nanoparticles in toluene, add acetone for centrifugation, the centrifugation rate is 10000 - 15000 rpm, and the centrifugation time is 8 - 15 minutes; repeat the operation of "disperse in toluene - add acetone for centrifugation" 2 - 3 times to obtain 130 - 200 mg of AgBiS2 solid particles; (2) Prepare AgBiS2 / PVDF - HFP composite fiber film First, prepare a mixed solution with a volume ratio of N,N - dimethylformamide to acetone of 1:1, then add the AgBiS2 solid particles prepared in step (1) to 8 - 10 g of the mixed solution, stir at room temperature for 4 - 6 h to make the single - layer AgBiS2 evenly distributed; then add PVDF - HFP to the mixed solution and stir overnight at room temperature; the mass dosage of AgBiS2 is 3 - 15% of the sum of the dosages of AgBiS2 and PVDF - HFP; electrospin the obtained AgBiS2 / PVDF - HFP mixed solution to obtain an AgBiS2 / PVDF - HFP composite fiber film with a thickness of 30 - 50 μm; (3) Prepare TPU fiber film First, weigh 3 - 5 g of DMF and 3 - 5 g of tetrahydrofuran to obtain a mixed solution, add 1.5 - 3.0 g of TPU particles to this mixed solution, and stir overnight at room temperature; electrospin the obtained TPU solution to obtain a TPU fiber film with a thickness of 20 - 100 μm; (4) Assemble the triboelectric nanogenerator Stick two pieces of conductive copper tape on the central outer surfaces of two PET films respectively, then place the AgBiS2 / PVDF - HFP composite fiber film and the TPU fiber film on the inner surfaces of the two PET films respectively. The AgBiS2 / PVDF - HFP composite fiber film and the TPU fiber film are separated by 2 insulating gaskets. Use the AgBiS2 / PVDF - HFP fiber film as the negative friction layer of the triboelectric nanogenerator and the TPU fiber film as the positive friction layer of the triboelectric nanogenerator; finally, use a medical waterproof PU film to encapsulate the conductive copper tape, PET film, AgBiS2 / PVDF - HFP composite fiber film and TPU fiber film, thereby obtaining a triboelectric nanogenerator with a double - electrode structure based on the AgBiS2 / PVDF - HFP composite fiber film.
2. The preparation method of a triboelectric nanogenerator based on a ternary nanocrystal / polymer composite fiber film as described in claim 1, characterized in that: In steps (2) and (3), the electrospinning voltage is set to 15 - 20 kV, the distance between the electrospinning needle and the collection device is 12 - 18 cm, the solution flow rate is set to 0.5 - 1.0 mL / h, the lateral movement distance of the collection device is set to 75 - 85 mm, the longitudinal distance is set to 150 - 170 mm, and the electrospinning time is 4 - 6 h.
3. The preparation method of a triboelectric nanogenerator based on a ternary nanocrystal / polymer composite fiber film as claimed in claim 1, characterized in that: In step (4), the flexible conductive copper tape has a size of 3 cm × 3 cm and a thickness of 30 - 50 μm, and two copper wires with a diameter of 0.15 mm are welded to the tail end of the flexible conductive copper tape; the AgBiS2 / PVDF-HFP composite fiber film has a size of 5 cm × 5 cm, the TPU fiber film has a size of 5 cm × 5 cm, the polyethylene terephthalate has a size of 5 cm × 5 cm and a thickness of 75 - 125 μm, the medical waterproof polyurethane film has a size of 5 cm × 5 cm and a thickness of 50 - 100 μm, the insulating gasket has a thickness of 0.1 - 0.3 mm, and the distance between two insulating gaskets is 2 - 4 cm.
4. A triboelectric nanogenerator based on an AgBiS2 / PVDF-HFP composite fiber film, characterized in that: It is prepared by the method according to any one of claims 1 - 3.