BN (boron nitride) enhanced friction nano-generator as well as preparation method and application thereof
By doping boron nitride nanosheets and foam metal substrates into TENG, the conductivity and energy harvesting capability of the device are enhanced, solving the problems of insufficient doping uniformity and interface charge transfer efficiency of TENG in vibration environment, and realizing high-precision vibration waveform recognition and tactile perception.
Patent Information
- Application Number
- CN202510888310.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-06-30
- Publication Date
- 2025-11-07
AI Technical Summary
Existing TENGs in the fields of vibration energy harvesting and self-powered sensing suffer from difficulties in controlling doping uniformity, limited interface charge transfer efficiency, and insufficient adaptability to complex vibration signals, making it difficult to achieve high-precision signal identification and multi-frequency vibration monitoring.
Boron nitride nanosheets-doped flexible polymers were used as composite dielectrics, and a foamed metal substrate was employed to enhance the conductivity and energy harvesting capability of the device. By studying the interfacial charge transport characteristics and device output performance, the physical mechanism of BNNSs doping enhancing dielectric polarization was revealed.
It achieves good output voltage and waveform stability under vibration environment, can be used as a sensor in vibration waveform recognition, has high sensitivity tactile signal detection capability, is suitable for monitoring the status of mechanical equipment and human-machine interface, and provides accurate tactile perception and recognition.
Smart Images
Figure CN120915162A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The application belongs to the technical field of friction power generation, and particularly relates to a BN enhanced friction nanogenerator and a preparation method and application thereof. BACKGROUND
[0002] In recent years, TENG sensors based on triboelectric effect have unique advantages in vibration energy harvesting and self-powered sensing due to their self-power generation and high impedance characteristics, and are widely used in monitoring low-frequency vibration environments such as machines, vehicles, bridges and human body movements. However, there are still deficiencies in the quantitative analysis of different vibration energies, multi-frequency vibrations and waveform characteristics of TENGs with doping process. There are experiments that design doping related materials, improve the output performance and energy conversion efficiency by changing the dielectric layer and TENG under ordered doping, the peak power is increased from 0.78 mW to 3.26 mW, about 4.18 times, and it is verified in the field of vibration energy collection and human-computer interaction sensing, which shows the potential of TENG in practical application. However, the limitations of ordered doping structure, the difficulty in controlling the uniformity of doping, the limitation of interface charge transfer efficiency and the insufficient adaptability to complex vibration signals make it difficult for TENG to realize high-precision signal recognition and multi-frequency vibration monitoring in the vibration field. SUMMARY
[0003] Based on the above technical problems, the application designs a BNNSs doped flexible polymer as a composite dielectric, and adopts a foam metal substrate to enhance the conductivity and energy collection capacity of the device. The relationship between the interface charge transfer characteristics and the output performance of the device is studied, the physical mechanism of BNNSs doping enhanced dielectric polarization is revealed, and the evolution law of the interface potential regulation of the friction material and the waveform signal characteristics is clarified.
[0004] The specific scheme of the application is as follows:
[0005] One of the purposes of the application is to provide a BN enhanced friction nanogenerator, which comprises: a boron nitride nanosheet doped flexible polymer, a foam metal and a metal electrode sheet; wherein one end of the foam metal is attached with the metal electrode sheet, and the other end is packaged with the boron nitride nanosheet doped flexible polymer.
[0006] Preferably, the boron nitride nanosheet is obtained by ball milling method from hexagonal boron nitride as raw material.
[0007] Preferably, the flexible polymer is selected from at least one of polydimethylsiloxane, polyvinylidene fluoride, polytetrafluoroethylene and polyimide.
[0008] Preferably, the foam metal is selected from at least one of foam copper, foam nickel and foam silver.
[0009] Preferably, the metal electrode sheet is selected from at least one of copper sheet, aluminum sheet and silver sheet.
[0010] A second object of the present application is to provide a preparation method of the BN enhanced triboelectric nanogenerator, comprising: S1, mixing boron nitride nanosheets with a flexible polymer, mixing with a curing agent after ball milling treatment to obtain a mixed solution; S2, attaching a metal electrode sheet to one end of the foam metal and immersing the other end in the mixed solution, and curing to obtain the BN enhanced triboelectric nanogenerator.
[0011] Preferably, in S1, the mass ratio of the boron nitride nanosheets to the flexible polymer is 0.4-0.7:1.
[0012] Preferably, in S1, the rotation speed of the ball milling treatment is 300-600 rpm, and the ball milling treatment is performed for 12-20 h.
[0013] Preferably, in S1, the rotation speed of the ball milling treatment is 500 rpm, and the ball milling is performed for 0.5-1 h in an intermittent mode with a pause of 10-20 min.
[0014] A third object of the present application is to provide an application of the BN enhanced triboelectric nanogenerator as a sensor in vibration waveform identification.
[0015] The present application has the following advantages:
[0016] The present application has the following advantages: BRIEF DESCRIPTION OF DRAWINGS
[0017] Figure 1 It is a preparation flowchart of the BN enhanced triboelectric nanogenerator;
[0018] Figure 2 It is a SEM image of the boron nitride nanosheet powder in the negative friction layer prepared in Example 1;
[0019] Figure 3 It is a Fourier transform infrared absorption spectrum of the boron nitride nanosheet powder in the negative friction layer prepared in Example 1;
[0020] Figure 4 It is a structure schematic diagram and an actual sample diagram of the BNP-TENG obtained in Example 1, wherein (a) is an internal material 3D diagram; (b) is an actual sample diagram;
[0021] Figure 5The TENG voltage signal comparison and analysis diagram of the triboelectric nanogenerator described in Example 1 and Comparative Example 1; wherein (a) voltage comparison of gradually increasing vibration energy; (b) waveform analysis of different vibration energies;
[0022] Figure 6 The charge transfer mechanism of the BNP-TENG obtained in Example 1 under different working conditions; wherein (a) charge transfer mechanism under vibration; (b) charge transfer mechanism under contact;
[0023] Figure 7 The impact number stability test diagram of the BNP-TENG obtained in Example 1; wherein (a) impact test schematic diagram; (b) impact number voltage comparison diagram; (c) stage impact waveform analysis;
[0024] Figure 8 The waveform analysis of the BNP-TENG obtained in Example 1 under different frequencies of sine wave;
[0025] (a) 10Hz; (b) 50Hz; (c) 100Hz;
[0026] Figure 9 The waveform analysis of the BNP-TENG obtained in Example 1 under different frequencies of square wave; (a) 10Hz;
[0027] (b) 50Hz; (c) 100Hz;
[0028] Figure 10 The waveform analysis of the BNP-TENG obtained in Example 1 under different frequencies of triangular wave;
[0029] (a) 10Hz; (b) 50Hz; (c) 100Hz. DETAILED DESCRIPTION
[0030] In the following, the technical solutions of the present application will be described in detail through specific embodiments, but it should be clear that these embodiments are used for illustration, but not to be interpreted as limiting the scope of the present application.
[0031] The polydimethylsiloxane (C2H6OSi) used in the following examples n , the manufacturer is Dow Chemical (China) Co., Ltd.; the manufacturer of foamed copper is Kunshan Longshengbao Electronic Material Co., Ltd.; anhydrous ethanol and hexagonal boron nitride are purchased from Shanghai Aladdin Biochemical Technology Co., Ltd.
[0032] In the following examples, boron nitride nanosheets are prepared by ball milling method using hexagonal boron nitride as raw material.
[0033] Example 1
[0034] A BN enhanced friction nanogenerator, comprising: boron nitride nanosheet doped PDMS, foam copper and copper sheet; wherein one end of the foam metal is attached with the copper sheet, and the other end is packaged with the boron nitride nanosheet doped PDMS.
[0035] The flowchart of the preparation method of the BN enhanced friction nanogenerator is shown in Figure 1 The specific steps include:
[0036] S1, mix pure boron nitride nanosheet powder and PDMS according to a mass ratio of 0.5:1, put them into a stainless steel ball mill jar for grinding, use a planetary ball mill during the process, set the speed to 500 rpm, and use an intermittent mode of running for 1 h and pausing for 15 min, continue for 15 h, obtain a mixed solution of BNNNs and PDMS, mix the mixed solution of BNNNs and PDMS with the curing agent according to a ratio of 10:1, stir and then place in an ultrasonic cleaner for 15 min to eliminate air bubbles.
[0037] S2, wash the foam copper sheet with a thickness of 0.5 mm with anhydrous ethanol, dry it, and then attach a copper foil sheet to one end of the foam copper, immerse the other end of the foam copper into the mixed solution of BNNNs and PDMS (recorded as BNNSs / PDMS composite solution), and solidify at room temperature after eliminating air bubbles. Thus, a BNP-TENG with a size of 6x8 cm can be prepared.
[0038] The boron nitride nanosheet powder in the negative electrode friction layer of the embodiment is characterized, and the SEM image is shown in Figure 2 The Fourier transform infrared absorption spectrum is shown in Figure 3 .
[0039] As can be seen from Figure 2 , the BNNSs observed under a scanning electron microscope with a 500 nm field of view exhibit a thin sheet structure, the surface is relatively smooth as a whole, has a transverse size of hundreds of nanometers to several microns, the edge part is relatively wrinkled, and the sheet layer is locally stacked, indicating that the mechanical shearing force and impact force of the hard alloy ball on the h-BN weaken the interlayer bonding force, so that the nanosheet is peeled off, and the mechanical peeling process still maintains a good two-dimensional structure, the interlayer interaction is not completely destroyed, and no serious fragmentation occurs.
[0040] As can be seen from Figure 3 , there is a clear absorption peak at 800 cm -1 , which corresponds to the vibration mode of B-N-B bond, in addition, a strong absorption peak is also observed at 1370 cm -1 , which corresponds to the stretching vibration of B-N bond. In the vicinity of 3000 cm -1 , the spectrum shows an absorption peak, which corresponds to the -CH2 stretching vibration, and in the vicinity of 3420 cm -1The -OH vibration peak was observed, which indicated that the BNNSs still maintained the hexagonal layered structure of h-BN, and the basic chemical composition of the material did not change fundamentally.
[0041] The structural schematic diagram of the BNP-TENG obtained in the embodiment and the actual sample diagram are as shown in FIGS. 1 and 2. Figure 4 As shown in the figures, (a) is a 3D diagram of the internal material of the BNP-TENG; and (b) is the mechanical flexibility of the BNP-TENG.
[0042] As can be seen, (a) shows the layered structure of the BNP-TENG, in which the metal friction layer adopts metal foam copper, and the BNNSs are uniformly distributed in the negative electrode friction layer; and (b) shows the actual sample size of the BNP-TENG and the morphology thereof in a twisted state, which indicates that the BNP-TENG not only has a reasonable layered structure design, but also has excellent mechanical flexibility.
[0043] Embodiment 2
[0044] A BN enhanced triboelectric nanogenerator, comprising: boron nitride nanosheet doped PDMS, foam nickel and a copper sheet; wherein one end of the foam nickel is attached with the copper sheet, and the other end is packaged with boron nitride nanosheet doped PDMS.
[0045] The preparation method of the BN enhanced triboelectric nanogenerator described in the embodiment includes the following specific steps:
[0046] S1, mix pure boron nitride nanosheet powder and PDMS according to a mass ratio of 0.4:1, put them into a stainless steel ball mill jar for grinding, use a planetary ball mill during the process, set the rotation speed to 420 rpm, and use an intermittent mode of running for 0.5 h and pausing for 10 min, continue for 20 h, obtain a mixed solution of BNNNs and PDMS, mix the mixed solution of BNNNs and PDMS with a curing agent according to a ratio of 8:1, stir and then place in an ultrasonic cleaner for 15 min to eliminate air bubbles.
[0047] S2, wash the foam nickel sheet with a thickness of 0.5 mm with anhydrous ethanol, dry it, attach a copper foil sheet to one end of the foam nickel, and immerse the other end of the foam nickel in the mixed solution of BNNNs and PDMS (denoted as BNNSs / PDMS composite solution), and then solidify at room temperature after eliminating air bubbles.
[0048] Embodiment 3
[0049] A BN enhanced triboelectric nanogenerator, comprising: boron nitride nanosheet doped polyvinylidene fluoride, foam copper and a copper sheet; wherein one end of the foam copper is attached with the copper sheet, and the other end is packaged with boron nitride nanosheet doped polyvinylidene fluoride.
[0050] Comparative Example 1
[0051] A friction nanogenerator, comprising: PDMS, foam copper and copper sheet; wherein one end of the foam copper is attached with the copper sheet, and the other end is packaged with the PDMS. The preparation method comprises the following steps:
[0052] S1, mix PDMS with curing agent at a ratio of 10:1, stir and then place in an ultrasonic cleaner for 15 min to eliminate bubbles.
[0053] S2, wash the foam copper sheet with a thickness of 0.5 mm with anhydrous ethanol, dry, then attach a copper foil sheet at one end of the foam copper, immerse the other end of the foam copper in the PDMS solution, eliminate bubbles, and then solidify at room temperature to obtain the product.
[0054] The performance of the friction nanogenerator described in Example 1 and Comparative Example 1 was tested, as follows:
[0055] Figure 5 The voltage signal comparison and analysis of the BNP-TENG described in Example 1 and the TENG without doped BN described in Comparative Example 1 under gradually increasing vibration energy are shown.
[0056] As shown in the figure, the voltage under three vibration energies in (a) gradually increases, and the voltage output performance of the BNP-TENG is more excellent. Through the waveform characteristic analysis in (b), it is found that the process of vibration energy decay is consistent, and the voltage signal is also weakened with the vibration process. The BNP-TENG has more obvious waveform characteristics, and the voltage signal presents a nonlinear change with the increase of vibration energy, which indicates that the BNP-TENG has the ability to realize vibration wave recognition, and relies on the characteristics of the output voltage waveform rather than the intensity to identify the vibration wave.
[0057] Figure 6 The charge transfer mechanism of the BNP-TENG under different working modes is shown.
[0058] As shown in (a), when the vibration has not started, the BNP-TENG is in a static state, and the internal charge has not been transferred, and the whole is in a potential balance. When the external vibration acts on the BNP-TENG, the Cu / BN@PDMS layer and the Cu / BN@PDMS layer are in periodic contact and separation, and the triboelectric effect makes the interface charge redistribution, thereby generating moving charges. With the continuous vibration of the system, the negative charges enter the Cu / BN@PDMS layer through the ground wire, and offset the positive charges on the surface thereof. In order to maintain the charge balance, additional negative charges flow to the ground wire, thereby completing a complete charge transfer cycle. When the vibration wavelength acts on the BNP-TENG, the charge transfer and release in the device enter a stable state, so that the BNP-TENG can continuously output electrical signals during the vibration process. However, when the vibration gradually decays, the vibration amplitude of the PDMS layer rapidly decreases, the strength of the contact and separation decreases, resulting in weakening of the charge transfer process, and finally tends to be static until the charge transmission completely stops.
[0059] Figure (b) shows that when the weight is in contact with the BNP-TENG, the PDMS surface is negatively charged, the weight surface is positively charged, and when separated, the internal friction layer generates induced charges. At this time, the electrons flow to the ground through the ground wire, and when reaching the maximum separation height, most of the electrons flow to the ground. In order to maintain the charge balance, the electrons will flow to the friction layer of the BNP-TENG, thereby forming an electric current. This indicates that the BNP-TENG can realize efficient charge conversion in different power generation modes, effectively convert external vibration energy and contact mechanical energy into electrical signals, and its output characteristics are closely related to the vibration frequency, intensity and contact weight.
[0060] Figure 7 The impact of the BNP-TENG test schematic diagram and the voltage and waveform analysis diagram of the BNP-TENG under different impact times are shown.
[0061] As shown in the figure, (a) shows a schematic diagram of the stability test of the BNP-TENG surface impacted by the weight, for evaluating the durability and voltage output stability of the BNP-TENG under long-term mechanical impact; (b) compares the stability of the vibration output voltage waveform of the BNP-TENG in the original state and after every 1000 impacts, the results show that during the multiple impacts, the output voltage of the BNP-TENG remains at 2.5V, with only a slight fluctuation; (c) normalizes the output voltage obtained by the test, the results show that all voltage waveforms remain consistent under different impact times, without obvious changes, and the waveform characteristics are highly consistent, without obvious attenuation or distortion. This indicates that the BNP-TENG can still maintain stable output voltage performance under long-term impact, with high durability and reliability. In addition, the consistency of the normalized voltage waveform further proves that the charge transfer and voltage output mechanism of the BNP-TENG under external mechanical impact has good repeatability.
[0062] Analysis of BNP-TENG output signal waveform characteristics under different vibration environments
[0063] Figure 8 The output voltage waveform analysis diagram at different frequencies within the sine wave period is shown. As shown in the figure, under the vibration conditions of frequency 10Hz, 50Hz, 100Hz, the waveform period of the sine wave is 1.001s, 0.199s, 0.1s respectively, and the voltage waveform also changes significantly with the increase of frequency, which indicates that the output voltage waveform of BNP-TENG is significantly affected by the vibration frequency, and with the increase of frequency, the output voltage waveform not only shortens the period, but also changes the waveform, and the relative error in the corresponding measurement is 0.1%, which shows excellent accuracy between 50Hz and 100Hz, and the signal waveform characteristics collected under different frequency vibration modes show significant differences.
[0064] Figure 9 The output voltage waveform analysis diagram at different frequencies within the square wave period is shown. As shown in the figure, under the vibration conditions of frequency 10Hz, 50Hz, 100Hz, the waveform period of the square wave is 0.998s, 0.199s, 0.101s respectively, and the voltage waveform also changes significantly with the increase of frequency, which indicates that BNP-TENG can still respond effectively to vibration changes at different frequencies, and its output waveform can change with the change of frequency, with strong adaptability and variability, and the relative error in the corresponding measurement is 0.1-0.2%, which shows excellent accuracy between 50Hz and 100Hz, and the output voltage waveform characteristics collected under different frequency vibration modes show significant differences.
[0065] Figure 10The waveform analysis diagram under different frequencies in the triangular wave period is shown. As shown in the figure, under the vibration conditions of frequencies 10Hz, 50Hz, 100Hz, the waveform periods of the triangular wave are 1.007s, 0.199s, 0.1s respectively, and the output voltage waveform also changes significantly with the increase of frequency, which shows that the signal waveform characteristics collected by the BNP-TENG under different vibration modes show significant differences, and the relative error in the corresponding measurement is 0.1-0.7%, and excellent accuracy is shown between 50Hz and 100Hz.
[0066] The BNP enhanced friction nanogenerator provided by the application is a composite dielectric TENG, which effectively improves the polarization effect and charge transfer capacity of the material, so that the device can generate stronger triboelectric signals under external small mechanical stimulation, thereby realizing high-sensitivity detection of small tactile signals. Compared with the traditional TENG tactile sensor, the BNP-TENG further optimizes the stability and high response of the output voltage waveform, so that it can monitor the working state of different mechanical equipment in the fields of high-speed rail, ship engine and industrial robot. Since it does not need external power supply, the BNP-TENG can work continuously and stably and can provide accurate identification of different touch modes, and make the robot have a tactile perception ability closer to human skin; in the medical rehabilitation field, the sensor can monitor the touch pressure distribution of patients in rehabilitation training in real time, and provide more accurate rehabilitation data support for doctors. In addition, the BNP-TENG can also be applied to intelligent human-computer interaction interface, such as integrated in wearable devices, to realize passive control of electronic devices through different touch modes, and provide new possibilities for future low-power intelligent interaction technology.
[0067] The above is only the preferred specific embodiment of the application, but the protection scope of the application is not limited to this, any person skilled in the art can make equivalent replacement or change according to the technical solution and the inventive concept of the application within the technical range disclosed by the application, which should be covered within the protection scope of the application.
Claims
1. A BN-enhanced tribo-nanogenerator, characterized in that, The application relates to a BN-enhanced tribo-nanogenerator, which comprises the following components: a flexible polymer doped with boron nitride nanosheets, a foam metal and a metal electrode sheet; one end of the foam metal is attached to the metal electrode sheet, and the other end is packaged with the flexible polymer doped with boron nitride nanosheets. The boron nitride nanosheets are obtained by ball milling from hexagonal boron nitride.
2. The BN-enhanced tribo-nanogenerator of claim 1, wherein, The flexible polymer is at least one selected from polydimethylsiloxane, polyvinylidene fluoride, polytetrafluoroethylene and polyimide.
3. The BN-enhanced tribo-nanogenerator according to claim 1 or 2, wherein, The foam metal is at least one selected from foam copper, foam nickel and foam silver. 4.The BN-enhanced tribo-nanogenerator according to claim 1 or 2, characterized in that, The metal electrode sheet is at least one selected from copper sheet, aluminum sheet and silver sheet.
5. The BN-enhanced tribo-nanogenerator according to claim 1 or 2, wherein, The application further relates to a preparation method of the BN-enhanced tribo-nanogenerator.
6. A method for preparing a BN-enhanced tribo-nanogenerator, characterized in that, S1, mixing boron nitride nanosheets with a flexible polymer, mixing with a curing agent after ball milling treatment to obtain a mixed solution; S2, attaching a metal electrode sheet to one end of a foam metal, immersing the other end into the mixed solution, and curing to obtain the BN-enhanced tribo-nanogenerator. In S1, the mass ratio of the boron nitride nanosheets to the flexible polymer is 0.4-0.7:
1.
7. The method of claim 6, wherein the BN-enhanced tribo-nanogenerator is prepared by the steps of: In S1, the rotation speed of the ball milling treatment is 300-600 rpm, and the ball milling treatment is performed for 12-20 h.
8. The method for preparing a BN-enhanced triboelectric nanogenerator according to claim 6 or 7, characterized in that, In S1, the rotation speed of the ball milling treatment is 500 rpm, the ball milling is performed for 0.5-1 h in an intermittent mode with 10-20 min of pause.
9. The method for preparing a BN-enhanced triboelectric nanogenerator according to claim 6 or 7, characterized in that, 10. Application of the BN-enhanced tribo-nanogenerator in vibration waveform identification as a sensor, wherein the BN-enhanced tribo-nanogenerator is prepared by the method in any one of claims 1-5 or any one of claims 6-9.