Friction nano-generator based on Kelvin drip generator corona discharge enhancement and preparation method thereof

Abstract

The invention provides a Kelvin drip generator corona discharge enhancement-based friction nanometer generator and a preparation method thereof. Wherein the generator comprises a Kelvin water dripping machine, high voltages at two ends of the Kelvin water dripping machine are respectively coupled to a back gate electrode and a suspension needle, a non-uniform electric field is constructed in a needle tip-FEP area, corona discharge is triggered, charges are directionally injected into an FEP / liquid drop system, and the FEP / liquid drop system is charged. The injected charges are connected in parallel into the device through a multi-branch capacitor network formed by the back gate electrode, the upper electrode / the lower electrode and the FEP. According to the invention, through cooperation of exogenous pumping and liquid drop charge shuttling (DSG), single-drop transfer charge and open-circuit voltage are significantly improved, and direct-current stepped accumulative output is maintained.

Description

Technical Field

[0001] This invention belongs to the field of triboelectric nanogenerator technology, and particularly relates to a triboelectric nanogenerator based on Kelvin dripping water generator corona discharge enhancement and its preparation method. Background Technology

[0002] In the context of the global push for low-carbon and sustainable energy, the development of small-scale, distributed, self-sufficient energy harvesting technologies is of great significance. [1-4] Triboelectric nanogenerators can convert low-frequency mechanical disturbances into electrical energy, making them a strong candidate for self-powered sensing and distributed energy harvesting. [5,6] Traditional triboelectric nanogenerators primarily output AC pulses, requiring rectification and energy management. This results in complex systems with rectification and matching losses, making direct and stable power supply difficult, limiting average output power, and causing energy loss due to rectification and impedance mismatch. Furthermore, the intermittent nature of the pulses adds further complexity to energy management, a point repeatedly highlighted in power management reviews and systematic packaging research. [7] .

[0003] Solid-liquid triboelectric nanogenerators are extremely sensitive to environmental humidity. Under high humidity conditions, the increased surface water film and ion layer enhance surface conductivity and carrier recombination, leading to a decrease in output charge / voltage and a deterioration in stability. Systematic reviews and experiments consistently observe a trend of "the higher the humidity, the weaker the output." [8,9] For auxiliary gain paths that rely on gas-phase ionization / corona discharge, high humidity also increases the corona initiation voltage and decreases the corona current, thereby raising the start-up threshold and reducing the injectable charge flux.

[10] .

[0004] At the device physics level, traditional droplet-based triboelectric nanogenerators (DNGs) are mostly dominated by interface effects. The surface charge density of the triboelectric layer limits both the transferable charge per drop and the achievable open-circuit voltage and energy density, making it difficult to directly and stably drive low-power devices in ultra-low frequency scenarios. Furthermore, droplet-based DNGs are highly sensitive to wettability, contact area, and droplet dynamics (contact angle, droplet spreading and retraction, and splashing all significantly alter the magnitude of the effect), resulting in low single-droplet energy density and open-circuit voltage, as well as easy charge decay. In particular, droplet-based triboelectric nanogenerators (DNGs) can directly harvest the mechanical energy of thin water streams from raindrops and fog droplets, demonstrating unique application prospects in water-rich or humid environments. [11-15] .

[0005] However, traditional DNGs are often limited by their low single-droplet charge density, the need for complex energy management circuits for AC output, and the strong dependence of performance on surface wettability, which restricts their feasibility for long-term deployment in low-frequency, humid environments. [11,12,16] Recently, Dong Jun [17,18]The DC DNG and "total-current" droplet triboelectric nanogenerator proposed by researchers can directly generate DC output and reduce the burden of energy management. However, devices dominated by interface effects still face bottlenecks in charge density and storage capacity. Furthermore, current research on charge transfer mechanisms and functional integration is insufficient, making the output susceptible to external disturbances and operating condition fluctuations, resulting in poor stability and reproducibility, and hindering fine modulation. [19,20] . Summary of the Invention

[0006] The purpose of this invention is to overcome the shortcomings of the prior art and provide a triboelectric nanogenerator based on Kelvin dripping water generator corona discharge enhancement and its preparation method.

[0007] This invention connects the high voltage at both ends of the Kelvin drip generator (KWD) to the suspension needle and the back grid electrode, respectively. It utilizes the strong non-uniform electric field in the suspension needle-FEP region to trigger corona discharge, thereby directionally injecting charge carriers from the gas phase into the FEP / droplet system. The injected charge is incorporated into the device through a multi-branch capacitor network composed of the back grid-upper / lower electrode-triboelectric layer, enabling the external pump and the droplet charge shuttle (DSG) process to work together, significantly improving the single droplet transferred charge and open-circuit voltage, while maintaining DC stepped cumulative output.

[0008] The present invention adopts the following technical solution: A triboelectric nanogenerator based on Kelvin dripping motor corona discharge enhancement includes a Kelvin dripping motor and a capacitively coupled back-gate TC-DNG. The TC-DNG is composed of PTFE, with a back-gate electrode arranged on the PTFE and an FEP arranged on the back-gate electrode. An upper electrode and a lower electrode are arranged on the FEP, and a suspension needle is fixed at the center of the upper electrode. The high voltage at both ends of the Kelvin dripping motor is coupled to the back-gate electrode and the suspension needle, respectively, to build a strong non-uniform electric field in the needle tip-FEP region, triggering corona discharge and directionally injecting charge into the FEP / droplet system. The injected charge is connected in parallel to the device through a multi-branch capacitor network formed by the back-gate electrode-upper / lower electrode-FEP.

[0009] Furthermore, the Kelvin drip generator consists of two sets of metal rings A and B, and metal bowls C and D. Metal bowl C is connected to metal ring B, and metal bowl D is connected to metal ring A to form a closed loop. A water tank and a water distributor are arranged above metal rings A and B respectively. The water tank and the water distributor are connected. The water tank provides droplets to metal rings A and B through the water distributor. A gas discharge tube is connected in parallel between metal rings A and B by a wire.

[0010] Furthermore, the droplet height was 50cm.

[0011] Metal ring A is connected to metal bowl D with enameled copper wire, and metal ring B is connected to metal bowl C with enameled copper wire.

[0012] Furthermore, the working method of the Kelvin drip generator includes: the weak initial net charge on the metal bowl induces an opposite charge distribution at the adjacent metal ring, and then the falling droplet is polarized and carries a charge consistent with the induced polarity when it passes through the metal ring. The droplet is collected into the corresponding metal bowl and feeds the carried charge back to the original side.

[0013] Furthermore, the droplet system includes providing a droplet between the suspending needle and the back grid electrode, with a droplet height of 10-20 cm.

[0014] The fabrication steps of the triboelectric nanomotor based on Kelvin dripping motor corona discharge enhancement are as follows: Step 1. Place the back grid electrode flat onto the PTFE substrate in a top-to-bottom order.

[0015] Step 2. Fix a wire between the back grid electrode and the PTFE substrate to connect one pole of the Kelvin drip motor to the back grid electrode; Step 3. Apply the FEP film, which has been cleaned with anhydrous ethanol, tightly to the top of the back grid electrode; Step 4. Fix the upper and lower electrodes to the upper and lower ends of the FEP film respectively, fix a suspension needle at the center of the upper electrode, and lead wires from the upper / lower electrodes to connect the load.

[0016] Furthermore, the PTFE substrate dimensions are 50×70×4mm.

[0017] Furthermore, the back gate electrode is made of copper foil with a thickness of 0.15 mm.

[0018] Furthermore, the FEP film size is 50×70×0.08mm.

[0019] Furthermore, both the upper and lower electrodes are made of copper foil with dimensions of 50×10×0.1mm.

[0020] Furthermore, the suspension needle is made of platinum, with a length of 10 mm and a diameter of 0.2 mm.

[0021] The beneficial effects of this invention are: By combining displacement current and conduction current, the energy conversion efficiency of charge and the energy density of a single droplet are improved. The short-circuit current of TCDNG is increased from 2μA to 80μA, the single droplet transferred charge is increased from the baseline of 25nC to the order of 80nC, and the single droplet output voltage is increased from 50V to 200V. Attached Figure Description

[0022] Figure 1This is a schematic diagram of the structure of the present invention; Figure 2 This is a schematic diagram of the Kelvin drip motor structure of the present invention; Figure 3 This is a schematic diagram of the power generation device structure of the present invention; Figure 4 This is a schematic diagram of the corona discharge charge transfer under two working conditions of the suspended needle-back grid electrode of the present invention; (1) its suspended needle negative potential - back grid electrode positive potential, (2) suspended needle positive potential - back grid electrode negative potential. Figure 5 The following are diagrams showing the state after the invention is installed: (a) the droplet is in contact with the upper electrode probe, (b) the droplet is between the upper and lower electrodes, and (c) the droplet is in contact with the lower electrode.

[0023] Figure 6 The images show the entire process of a triboelectric nanogenerator (K-TCDNG) enhanced by Kelvin dripping corona discharge, captured by a high-speed camera. I represents the droplet falling, II represents the droplet spreading and contacting the upper electrode, III represents the droplet contracting, IV represents the droplet sliding, and V represents the droplet contacting the lower electrode.

[0024] Figure 7 The diagrams show the current, charge, and voltage output under two operating conditions: (a) is a comparison diagram of the current when the back grid electrode potential is positive and negative; (b) is a comparison diagram of the charge when the back grid electrode potential is positive and negative; (c) is a comparison diagram of the voltage when the back grid electrode potential is positive and negative; (d) is a comparison diagram of the current of TC-DNG; (e) is a comparison diagram of the current of K-TCDNG; and (f) is an enlarged view of (b).

[0025] Figure 8 The following are comparison charts of K-TCDNG output performance under different droplet frequencies, needle heights, and ambient humidity conditions: (a) Current comparison chart under different droplet frequencies, (b) Charge comparison chart under different droplet frequencies, (c) Voltage comparison chart under different droplet frequencies, (d) Current comparison chart under different needle heights, (e) Charge comparison chart under different needle heights, (f) Voltage comparison chart under different heights, (g) Current comparison chart under different ambient humidity conditions, (h) Charge comparison chart under different ambient humidity conditions, and (i) Voltage comparison chart under different ambient humidity conditions.

[0026] Figure 9 The potential simulation diagram shows the voltage of the needle with a height of 1 cm when the voltage of the needle and the back grid electrode are -6000V and +6000V respectively.

[0027] Figure 10 The potential simulation diagram is shown when the suspension needle and back grid electrode are -6000V and +6000V respectively, and the suspension needle height is 2cm.

[0028] Figure 11 The potential simulation diagram is shown when the suspension needle and back grid electrode are -6000V and +6000V respectively, and the suspension needle height is 3cm. Detailed Implementation

[0029] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention are described clearly and completely below. Obviously, the described embodiments are only some embodiments of this invention, not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0030] Terminology Explanation: (1) KWD refers to Kelvin drip motor.

[0031] (2) “K-TCDNG” refers to a DC droplet nanogenerator enhanced by KWD through corona discharge and coupled through back grid capacitor.

[0032] (3) "Back gate electrode" refers to the conductive layer located below the triboelectric layer (FEP) and capacitively coupled to it.

[0033] (4) "Suspended needle" refers to a metal needle (or needle-shaped electrode) with a small radius of curvature placed above the FEP, used to generate a local electric field and corona under high voltage.

[0034] (5) "Corona discharge" refers to the process of partial ionization of gas and the resulting stable small current discharge in a high non-uniform electric field.

[0035] (6) “Single drop parameters” refers to the peak current, transferred charge and open circuit voltage corresponding to a single drop event.

[0036] In traditional droplet-type triboelectric nanogenerators, which rely primarily on interface effects, the surface charge density of the triboelectric layer simultaneously limits both the upper limit of transferable charge per unit cycle and the upper limit of the voltage that can be established. To overcome this bottleneck, the "all-current" triboelectric nanogenerator introduces a "bulk effect" by placing a back gate electrode beneath the triboelectric layer, thereby enhancing the storage and transport capabilities of charge carriers through capacitive coupling.

[0037] Based on this, the present invention proposes a triboelectric nanogenerator based on enhanced corona discharge of a Kelvin dripping generator: the high voltage at both ends of the Kelvin dripping generator is coupled to the back grid electrode and the suspended needle, respectively, to construct a strong non-uniform electric field in the needle tip-FEP region, triggering corona discharge and directionally injecting charge into the FEP / droplet system; the injected charge is connected in parallel to the device through a multi-branch capacitor network composed of the back grid-upper / lower electrode-triboelectric layer, realizing the coordinated modulation of external pumping and droplet charge shuttle (DCS), such as... Figure 1 As shown.

[0038] Under the standard test conditions of this invention, the device's peak current per droplet (approximately 10 μA), transferred charge per droplet (approximately 25 nC), and output voltage (approximately 50 V) were increased to a peak current per droplet (approximately 80 μA), transferred charge per droplet (approximately 100 nC), and open-circuit voltage (approximately 200 V), corresponding to a single-droplet energy density of approximately 20 μJ·cm⁻¹. -2 The triboelectric nanogenerator based on Kelvin dripping motor corona discharge enhancement significantly improves electrical performance output.

[0039] The Kelvin water dropper (KWD) is a self-excited charge amplification device that requires no external power supply. Its core consists of two sets of metal rings A and B, and metal bowls C and D, which are cross-connected (metal bowl C connects to metal ring B, and metal bowl D connects to metal ring A) to form a closed loop. Figure 2 As shown, its working process includes: First, the weak initial net charge on the metal bowl induces an opposite charge distribution at the adjacent metal ring. Then, as the falling droplet passes through the metal ring, it is polarized and carries a charge consistent with the induced polarity. The droplet is collected in the corresponding metal bowl and feeds the charge back to the original metal ring. Finally, due to the cross-connection, any tiny imbalance will be amplified on the opposite side and further enhanced in the next drop cycle, forming positive feedback, thus accumulating into positive and negative high potentials at both ends.

[0040] The present invention provides a triboelectric nanogenerator based on Kelvin dripping water generator corona discharge enhancement, wherein the preparation steps are as follows: Step 1. Following the top-to-bottom order, with the bottom PTFE substrate measuring 50×70×4mm, smoothly attach the back gate electrode (copper foil, 0.15mm thick) onto the PTFE substrate.

[0041] Step 2. Fix a wire between the back grid electrode and the PTFE substrate to connect one pole of the Kelvin drip motor to the back grid electrode.

[0042] Step 3. Apply a commercially available FEP film (50×70×0.08mm in size) that has been cleaned with anhydrous ethanol tightly to the top of the back gate electrode.

[0043] Step 4. Fix the upper and lower electrodes (copper foil, dimensions 50×10×0.1mm) to the upper and lower ends of the FEP film respectively. Fix a platinum needle (10mm long, 0.2mm in diameter) at the center of the upper electrode as a charge sampling needle, and lead wires from the upper and lower ends to complete the K-TCDNG device assembly. Figure 3 As shown.

[0044] The Kelvin drip generator is a commercially available device with a drip height of 50cm. Metal ring A and metal bowl D are connected by enameled copper wire, as are metal ring B and metal bowl C. A gas discharge tube (GDT) is connected in parallel between metal rings A and B. The GDT is also a commercially available device, sourced from EPCOS. Platinum needles (suspended needles) and the back grid electrode are connected to metal rings A and B respectively via wires to complete the Kelvin K-TCDNG device connection. Commercial sewing needles can also be used for the suspended needles.

[0045] During the experiment, droplets were prepared onto the FEP film using a plastic bucket equipped with a droplet tube and a flow regulator to ensure uniform flow. Each droplet had a volume of approximately 100 μL, and the droplet height was controlled by adjusting the height of the pipette. The suspension needle's angle and height were controlled using a plastic clamp. Voltage, current, and charge measurements were acquired using a high-bandwidth electrophysiological measurement platform. This platform consisted of a Keithley 6517B electrometer, a Keithley DMM6500 digital multimeter, and accompanying acquisition software (Kickstart). Signals were recorded and processed within a standardized sampling window. The Keithley 6517B has a voltage range limit of 200V; an external series voltage divider was used to extend the measurement range for determining the device's open-circuit voltage.

[0046] During the experiment, it was found that the Kelvin drip generator (KWD) accumulated positive and negative high potentials at its two ends after self-excitation. When the metal ring A section was connected to the suspension needle and the metal ring B section was connected to the back grid electrode, the field enhancement caused by the small radius of curvature of the needle tip created a strong non-uniform electric field near the needle tip. Once the local field strength exceeded the corona induction threshold, the air was ionized to produce electrons and positive ions, such as... Figure 3 As shown. Carrier migration under two polarities: negative at the needle tip and positive at the back gate, as... Figure 4 As shown in (1), electrons are attracted to the back gate / friction layer (FEP) side, with positive ions pointing towards the needle tip, and electrons mainly accumulate on the surface of the friction layer (FEP); the needle tip is positive and the back gate is negative, as shown in (1). Figure 4 As shown in (2), positive ions tend to move towards the back gate / friction layer (FEP), and positive ions mainly accumulate on the surface of the friction layer (FEP). To describe the coupling process, a model is established. Figure 5 The equivalent circuit shown: the upper / lower electrodes are denoted as E1 and E2; the contact between the droplet and the two electrodes is represented by switches S1 and S2; the droplet's self-resistance is R1 and R2. The back gate electrode, the upper and lower electrodes, and the friction layer respectively constitute capacitor C. E1 C E2 C E3 The three are connected in parallel. The external circuit load is equivalent to a resistor R. L With switch S3. The corona injection between the tip and back gate electrodes is represented by a controlled current source I, with series / parallel equivalent leakage resistance R.A The current source continuously supplies C E3 Charge is injected, and then, with the droplet acting as a "timing switch," it is directionally extracted through S1 and S2 and output to the external circuit. A single droplet-device contact process can be divided into five stages, such as... Figure 6 As shown.

[0047] I. Drop: Before the droplet contacts the upper electrode probe, S1 is disconnected; C of the back-gate FEP E3 It is slowly charged under the action of corona current.

[0048] II. Spreading and contact with the upper electrode: S1 closes, the droplet and the charged FEP form a dense EDL, and the free carriers in the droplet are driven by the potential difference to C. E3 Coupling occurs when electrons / positive ions are extracted from E1 to CE1, as follows: Figure 5 (a)

[0049] III. Contraction: After the droplet leaves E1, S1 and S2 break, the electric double layer (EDL) structure gradually disappears, and the positive and negative charges return to the free state of C2, respectively; during this period, the charge continues to move towards C. E3 Injection, such as Figure 5 (b)

[0050] IV. Sliding: During the sliding process, the droplet gradually contracts under the action of surface tension, such as... Figure 5 (b)

[0051] After contact with the lower electrode, the current valve detaches: S2 closes, and the opposing charge carriers in C2 are transferred to C. E2 This completes one "extraction-output" cycle. The droplet leaves the device. If S3 is disconnected, the charge and voltage across E1 and E2 continue to accumulate unidirectionally; if S3 is connected to a load, it exhibits DC power supply, such as... Figure 5 (c)

[0052] In the circuit analysis above, the back gate electrode was cleverly utilized to enable it to play a role in the coupling capacitance C. E1 C E2 During the process, taking advantage of the positive potential of the back-gate electrode, the charge pump current source I constructed by corona discharge was recoupled, making it a capacitor C. E3 Charging significantly enhances the electrical performance of the device by increasing charge transfer during the contact between the droplet and the upper and lower electrodes E1 and E2. During the experiment, it was found that the potential of the back gate electrode could be either positive or negative when connected to a Kelvin drip generator, with different charge transfer processes. Figure 4 The time-domain response under two back-gate characteristics was compared: when the back-gate electrode is positive (needle tip is negative), the current significantly increases after the KWD starts oscillating, such as... Figure 7 (a) Magnify the single droplet waveform, as shown in Figure 1. Figure 7 In the middle (d), a typical bimodal characteristic is visible (corresponding to droplet contact E1 and E2), consistent with the "full current" mode of TC-DNG. The corresponding charge and voltage (e.g.) Figure 7 (b) Figure 7 In the middle (c) phase, the transfer amount increases monotonically in a stepwise manner, where Q1 and Q2 correspond to the transfer amounts during the upper / lower electrode contact stages, respectively. A slow increase occurs in the droplet gap, originating from the continuous corona effect on C. E3 Charging. When the back gate electrode is negative (needle tip is positive), the polarity of the single-drop current pulse reverses, such as... Figure 7 In the middle (e), the net charge and voltage form a monotonically negative step (e.g., Figure 7 (b) and (f) Figure 7 (c) The physical picture is as follows: positive ions accumulate in a limited way on the FEP surface. When the droplet comes into contact with E1, it first releases a small amount of positive charge. Then, under the enhanced EDL, electrons in the droplet are drawn to E1. The number of electrons increases further during the slip phase. Finally, when it comes into contact with E2, electron output is still the main output. Therefore, the overall net transfer is negative.

[0053] The system investigates the effects of droplet frequency, needle height, and ambient humidity on output, aiming to obtain a better operating window as droplet frequency increases (e.g., ...). Figure 8 In Figures (a) to (c) (8), the overall single-drop output (current, transferred charge, and voltage) of K-TCDNG decreases. This is because in the high-voltage region formed by the needle-back grid, the corona injection of charge into the FEP requires a certain interval time; the increased frequency shortens the interval between adjacent droplets, resulting in a reduction in the effective injection time before each drop arrives, thus reducing the extractable charge per drop. However, it should be noted that even at 3Hz, the single-drop performance of K-TCDNG still maintains an improvement of approximately 50% compared to the uncoupled Kelvin control, indicating that external injection still has a compensating effect at high droplet frequencies. The needle-FEP spacing determines both the corona yield and the capacitive coupling strength, thus playing a dual role in the output. Therefore, the output performance at different needle heights (e.g., ...) was investigated. Figure 8 In (d) to (f) of the middle section, while a small spacing can enhance the local field and reduce the corona initiation voltage, it can easily induce local breakdown or droplet splashing that contaminates the needle tip, thus weakening effective injection. Conversely, a large spacing results in insufficient ionization and weaker coupling. The effect of humidity on the corona initiation voltage was also investigated. Under 60% humidity conditions, the triboelectric nanogenerator with Kelvin dripping corona discharge enhancement still achieved a good electrical output enhancement effect (e.g., Figure 8 (g)-8 (i)). Simulated by electric field ( Figures 9-11It can be seen that the maximum electric field strength near the needle tip decreases with increasing height, leading to suppressed corona formation and injection. Experimentally, within the working range of 1-3 cm, the single-drop charge / voltage of K-TCDNG initially increases and then decreases, showing an overall downward trend. This is consistent with the coupling modulation of "air ionization-ion transport-capacitive coupling," and is also influenced by external factors such as droplet size and airflow disturbance. It is noteworthy that even when using a control device with relatively weak fundamental performance (TC-DNG short-circuit current ≈ 10 μA, single-drop charge ≈ 1.5 nC, single-drop voltage ≈ 5 V), K-TCDNG still achieves significant gain. Figure 8 (d) Figure 8 (f) This indicates that during the conduction phase, the proportion of exogenous charge from corona injection is much higher than the charge contributed solely by the EDL formed by droplet-FEP, thus reducing the dependence on the device's fundamental performance. Since increased humidity generally suppresses stable corona, the output performance under different ambient humidity levels was investigated. Figure 8 (g) Figure 8 In (i), the corona initiation voltage increases while the corona current decreases at the same voltage. The physical reason for this can be attributed to the energy dissipation and additional recombination introduced by water vapor. Under RH=60% conditions, K-TCDNG can still maintain obvious unidirectional stepped output and DC characteristics, indicating that the system has robustness in working in medium and high humidity environments.

[0054] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A triboelectric nanogenerator based on Kelvin dripping water generator corona discharge enhancement, characterized in that, The device includes a Kelvin drip starter and a capacitively coupled back-gate TC-DNG. The TC-DNG consists of PTFE, with the back-gate electrode arranged on the PTFE and the FEP arranged on the back-gate electrode. The upper and lower electrodes are arranged on the FEP, and the suspension needle is fixed at the center of the upper electrode. The high voltage at both ends of the Kelvin drip starter is coupled to the back-gate electrode and the suspension needle, respectively, to build a non-uniform electric field in the needle tip-FEP region, triggering corona discharge and injecting charge into the FEP / droplet system in a directional manner. The injected charge is connected in parallel to the device through a multi-branch capacitor network formed by the back-gate electrode-upper / lower electrode-FEP.

2. The generator according to claim 1, characterized in that, The Kelvin drip generator consists of two sets of metal rings A and B, and metal bowls C and D. Metal bowl C is connected to metal ring B, and metal bowl D is connected to metal ring A. A water tank and a water distributor are arranged above metal rings A and B respectively. The water tank and the water distributor are connected. The water tank provides droplets to metal rings A and B through the water distributor. A gas discharge tube is connected in parallel between metal rings A and B by a wire.

3. The generator according to claim 2, characterized in that, The droplet falls from a height of 50cm.

4. The generator according to claim 2, characterized in that, The metal ring A and the metal bowl D are connected by an enameled copper wire, and the metal ring B and the metal bowl C are connected by an enameled copper wire.

5. The generator according to claim 1, characterized in that, The droplet system includes: providing droplets at the suspension needle and back grid electrode, with a droplet height of 10-20 cm.

6. A method for preparing a triboelectric nanogenerator based on Kelvin dripping water generator corona discharge enhancement, characterized in that, Including the following: Step 1. Following the top-to-bottom order, smoothly attach the back grid electrode to the PTFE substrate; Step 2. Fix a wire between the back grid electrode and the PTFE substrate to connect one pole of the Kelvin drip motor to the back grid electrode; Step 3. Apply the FEP film, which has been cleaned with anhydrous ethanol, tightly to the top of the back grid electrode; Step 4. Fix the upper and lower electrodes to the upper and lower ends of the FEP film respectively. Fix a suspension needle at the center of the upper electrode. The suspension needle is made of platinum, with a length of 10 mm and a diameter of 0.2 mm. Lead wires from the upper and lower electrodes to connect the load.

7. The method according to claim 6, characterized in that, The PTFE substrate has dimensions of 50×70×4mm.

8. The method according to claim 6, characterized in that, The back grid electrode is made of copper foil with a thickness of 0.15 mm.

9. The method according to claim 6, characterized in that, The FEP film has dimensions of 50×70×0.08mm.

10. The method according to claim 6, characterized in that, Both the upper and lower electrodes are made of copper foil with dimensions of 50×10×0.1mm.

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