An underwater frictional nanogenerator device, a self-driven underwater acoustic communication system and a preparation method

Abstract

The application discloses an underwater friction nanogenerator device, a self-driven underwater acoustic communication system and a preparation method, which sequentially comprise, from top to bottom, a high-entropy energy material / LIG / Ecoflex composite electrode layer as a top layer, an intermediate layer for supporting the top layer and a bottom layer for adjusting acoustic-mechanical resonance characteristics; the high-entropy energy material / LIG / Ecoflex composite electrode layer sequentially comprises, from top to bottom, a high-entropy energy material film, a laser-induced graphene pattern and an Ecoflex elastomer film; the laser-induced graphene pattern is located on the surface of the Ecoflex elastomer film, and the high-entropy energy material film is deposited on the surface of the laser-induced graphene pattern by a magnetron sputtering technology.

Description

Technical Field

[0001] This invention belongs to the field of underwater communication and self-driven sensing technology, specifically relating to an underwater triboelectric nanogenerator device, a self-driven underwater acoustic communication system, and its preparation method. Background Technology

[0002] With increasing emphasis placed on marine resource exploration, environmental monitoring, national defense, and underwater Internet of Things (IoT), underwater wireless communication technology has become a crucial means of underwater information transmission. Among various underwater wireless communication methods, acoustic communication is considered the most feasible technology for achieving medium- and long-range underwater communication due to its significantly lower propagation loss in water compared to radio waves and light waves. Despite substantial progress, underwater equipment still faces a series of challenges in terms of power supply, sensing capabilities, and communication systems. The unique underwater operating environment leads to significant problems in power maintenance and charging, which severely restrict the performance of underwater equipment. Current battery technology cannot support the long-term, high-power operation requirements of underwater equipment. Furthermore, the complex and ever-changing marine environment places higher demands on existing sensor technologies, encompassing accuracy, stability, and environmental adaptability.

[0003] The main mechanisms for underwater acoustic energy harvesting include the piezoelectric effect and electromagnetic induction. Piezoelectric acoustic energy harvesters typically use ceramic materials such as lead zirconate titanate (PZT). The inherently high Young's modulus of PZT leads to a severe mismatch between the acoustic impedance and the water medium, causing most of the incident acoustic energy to be reflected rather than absorbed, resulting in low energy conversion efficiency. Furthermore, the brittleness of ceramic materials makes them prone to fatigue damage in complex hydrodynamic environments. While electromagnetic acoustic energy harvesters can achieve higher output power, they rely on bulky components such as coils and permanent magnets, making it difficult to meet the miniaturization and integration requirements of underwater equipment. Summary of the Invention

[0004] Purpose of the invention: To address the problem that existing sensors cannot cope with the complex and ever-changing marine environment, this invention proposes an underwater triboelectric nanogenerator device, a self-driven underwater acoustic communication system, and a preparation method to achieve underwater information transmission without the need for an external power source.

[0005] Technical solution: In the first aspect, the present invention proposes an underwater triboelectric nanogenerator device, which comprises, from top to bottom: a high-entropy energy material / LIG / Ecoflex composite electrode layer as the top layer, an intermediate layer for supporting the top layer, and a bottom layer for adjusting the acoustic-mechanical resonance characteristics;

[0006] The high-entropy energy material / LIG / Ecoflex composite electrode layer comprises, from top to bottom: a high-entropy energy material film, a laser-induced graphene pattern, and an Ecoflex elastomer film; the laser-induced graphene pattern is located on the surface of the Ecoflex elastomer film, and the high-entropy energy material film is deposited on the surface of the laser-induced graphene pattern by magnetron sputtering technology.

[0007] Furthermore, the intermediate layer comprises, from top to bottom: a planar spring structure layer, a fluorinated ethylene propylene copolymer film with silver electrodes, and a polylactic acid substrate; the planar spring structure layer converts vertical water pressure into horizontal deformation through its elastic structure.

[0008] Secondly, the present invention proposes a self-driven underwater acoustic communication system, including a transmitter, an underwater triboelectric nanogenerator device, and a receiver.

[0009] The transmitting end includes: a microcontroller, a power amplifier circuit, and a transmitting transducer; wherein, the microcontroller is used to convert the original text or image information to be transmitted into a binary sequence according to an encoding protocol, and then map the binary sequence into two different frequency sound signals; the power amplifier circuit is used to amplify the sound signals, and the transmitting transducer is used to generate corresponding sound waves in water based on the amplified sound signals;

[0010] The underwater triboelectric nanogenerator device is used to generate an alternating electrical signal corresponding to the frequency of the sound wave generated at the transmitting end.

[0011] The receiving end includes: a data acquisition circuit and a microprocessor; the data acquisition circuit is used to filter and amplify the alternating electrical signal generated by the underwater triboelectric nanogenerator device; the microprocessor is used to demodulate the electrical signal generated by the data acquisition circuit according to the same encoding protocol as the transmitting end, reconstruct the binary sequence, and finally restore it to the original text or image information.

[0012] Thirdly, this invention proposes a method for fabricating an underwater triboelectric nanogenerator device, comprising the following steps:

[0013] Laser-induced graphene patterns were prepared using a layered stacking and selective laser processing method.

[0014] Laser-induced graphene patterns were completely transferred into a flexible elastomer to obtain a flexible LIG / Ecoflex composite electrode.

[0015] A high-entropy energy material / LIG / Ecoflex composite electrode was obtained by depositing a high-entropy energy material / LIG / Ecoflex composite electrode on the surface of a LIG / Ecoflex composite electrode using magnetron sputtering technology.

[0016] A high-entropy energy material / LIG / Ecoflex composite electrode is used as the top layer to form an underwater triboelectric nanogenerator device.

[0017] Furthermore, the laser-induced graphene pattern is prepared using a layered stacking and selective laser processing method, including:

[0018] The base layer is obtained by sequentially layering and pasting the bottom adhesive layer, polyimide film, paper tape layer, intermediate adhesive layer and polypropylene film;

[0019] Laser cutting is performed along a predetermined path, with the cutting depth required to penetrate the polypropylene film, intermediate adhesive layer, paper tape layer, and extend into the polyimide film. After cutting, the polypropylene film, intermediate adhesive layer, and paper tape layer within the laser-cut area are manually peeled off and removed to expose the surface of the underlying polyimide film, forming the desired height difference structure.

[0020] By utilizing the thermal effect of lasers, the exposed surface of polyimide films is transformed into porous graphene structures, forming laser-induced graphene patterns.

[0021] Furthermore, the process of completely transferring the laser-induced graphene pattern into a flexible elastomer to obtain a flexible LIG / Ecoflex composite electrode includes:

[0022] Weigh component A and component B of Ecoflex 00-50 precisely at a mass ratio of 1:1, pour them into a mixing container and stir until the mixture is homogeneous and free of visible streaks.

[0023] The uniformly mixed prepolymer is degassed.

[0024] The degassed prepolymer is poured onto the laser-induced graphene pattern, ensuring that the prepolymer completely covers the target area and the laser-induced graphene pattern, and then cured as a whole.

[0025] After curing, the cured Ecoflex film is peeled off from the substrate. During this process, the laser-induced graphene pattern is completely transferred and embedded into the Ecoflex film to form a flexible LIG / Ecoflex composite electrode.

[0026] Furthermore, the deposition of a high-entropy energy material thin film on the surface of the LIG / Ecoflex composite electrode using magnetron sputtering technology to obtain the high-entropy energy material / LIG / Ecoflex composite electrode includes:

[0027] Using a LIG / Ecoflex composite electrode as a substrate, sputtering deposition was performed using a high-entropy alloy target. By controlling the sputtering time, a high-entropy energy material film with uniform thickness was prepared on the surface of the laser-induced graphene pattern. This high-entropy energy material film was combined with the three-dimensional porous structure of the laser-induced graphene pattern to obtain the high-entropy energy material / LIG / Ecoflex composite electrode.

[0028] Furthermore, the underwater triboelectric nanogenerator device, which uses a high-entropy energy material / LIG / Ecoflex composite electrode as the top layer, includes a high-entropy energy material / LIG / Ecoflex composite electrode layer as the top layer, an intermediate layer for supporting the top layer, and a bottom layer for adjusting the acoustic-mechanical resonance characteristics.

[0029] The intermediate layer comprises, from top to bottom: a planar spring structure layer, a fluorinated ethylene propylene copolymer film with silver electrodes, and a polylactic acid substrate; the planar spring structure layer converts vertical water pressure into horizontal deformation through its elastic structure.

[0030] The high-entropy energy material / LIG / Ecoflex composite electrode is bridged to the external wires via nickel-plated copper foil conductive tape, and the silver electrode of the fluorinated ethylene propylene copolymer film is connected to the external wires via aluminum conductive tape, thereby achieving effective acquisition of the output signal.

[0031] The sides and interfaces of the entire device are sealed and encapsulated using waterproof polyurethane tape.

[0032] Beneficial effects: Compared with the prior art, the present invention can effectively and reliably realize the transmission of underwater text information. At the same time, the present invention successfully integrates energy harvesting and information communication, and has great application potential in solving the energy bottleneck of underwater equipment and realizing long-term self-driven monitoring and communication. Attached Figure Description

[0033] Figure 1 Schematic diagram of LIG preparation;

[0034] Figure 2 Schematic diagram for fabricating high-entropy energy material / LIG / Ecoflex flexible electrode;

[0035] Figure 3 The surface resistivity of LIG composite electrode changes with engraving power and speed at an engraving precision of 1000 PPI.

[0036] Figure 4 This is a magnified view of the low resistance parameter region at 1000 PPI;

[0037] Figure 5The surface resistivity of LIG composite electrode changes with engraving power and speed at an engraving precision of 500 PPI.

[0038] Figure 6 This is a magnified view of the low resistance parameter region at 500 PPI;

[0039] Figure 7 The surface resistivity of the LIG composite electrode after sputtering HEA at a carving precision of 500 PPI is shown as the change in carving power and carving speed.

[0040] Figure 8 The surface resistivity of the LIG composite electrode after HEA sputtering changes with engraving power and speed at an engraving precision of 1000 PPI.

[0041] Figure 9 The trend of charge migration between HEA and FEP on the LIG composite electrode surface when adjusted from 200 PPI to 1000 PPI;

[0042] Figure 10 This is a schematic diagram of an underwater acoustic triboelectric nanogenerator.

[0043] Figure 11 This is a schematic diagram of a communication system circuit design.

[0044] Figure 12 This is a schematic diagram of the underwater low-frequency self-driven acoustic sensor and its communication system based on high-entropy energy materials according to the present invention.

[0045] Figure 13 The receiving end successfully demodulated the text message "O";

[0046] Figure 14 The receiving end successfully demodulated the text message "L". Detailed Implementation

[0047] To make the objectives, technical solutions, and advantages of the present invention clearer, the specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0048] Example 1:

[0049] Triboelectric nanogenerators (TENGs) based on contact electrification and electrostatic induction coupling effects have attracted widespread attention due to their unique advantages in harvesting low-frequency, weak mechanical energy. This embodiment discloses a method for fabricating an underwater triboelectric nanogenerator (TENG) device based on high-entropy energy materials, including the following steps:

[0050] Step 1: Using a layered stacking and selective laser processing technique, a laser-induced graphene (LIG) patterned substrate is prepared according to the following steps, such as... Figure 1 As shown:

[0051] S100: On a flat processing platform, layer and paste the following materials in sequence:

[0052] First layer: Kapton double-sided tape (as the base adhesive);

[0053] Second layer: Polyimide (PI) film (125µm thick, used as LIG precursor material);

[0054] Third layer: washi tape (as a sacrificial layer);

[0055] Fourth layer: Kapton double-sided tape (as an intermediate adhesive layer);

[0056] Fifth layer: Polypropylene (PP) film (250µm thick, as the top support layer).

[0057] Each layer is tightly bonded, without bubbles or wrinkles.

[0058] S110: Place the constructed multi-layer substrate on the processing platform of a laser engraving machine (model UNIVERSAL VLS6.75) for laser processing, including:

[0059] Contour cutting and selective peeling: Using laser parameters (power: 50%, scan rate: 20%, PPI: 1000), cut along a predetermined circular path to a depth penetrating the PP layer, the intermediate Kapton layer, the paper tape layer, and reaching the PI layer. After cutting, manually peel off the PP layer, the intermediate Kapton layer, and the paper tape layer within the circular area defined by the laser cut, exposing the underlying PI surface and forming the desired height difference structure.

[0060] LIG Patterning: LIG patterning is performed on the exposed PI region. A pre-designed conductive pattern is scanned using laser parameters (power: 32%, scan rate: 60%, PPI: 600). This combination of parameters utilizes the thermal effect of the laser to transform the surface PI into a porous graphene structure, forming a laser-induced graphene (LIG) pattern (approximately 150 µm high).

[0061] Step 2: Completely transfer the laser-induced graphene (LIG) pattern into the flexible elastomer to form a robust embedded composite electrode. The specific process steps are as follows: Figure 2 As shown, it includes:

[0062] S200: Preparation of the elastomer prepolymer: Accurately weigh component A and component B of Ecoflex 00-50 at a mass ratio of 1:1, pour them into a mixing container, and stir manually or mechanically for at least 5 minutes until the mixture is homogeneous and free of visible streaks. Then, place the homogeneous prepolymer in a vacuum drying oven and degas it at a vacuum of -1 kPa for 5 minutes to completely eliminate air bubbles and ensure uniform mechanical properties of the cured elastomer. Next, carefully pour the degassed Ecoflex 00-50 prepolymer onto the LIG patterned substrate surface prepared in step 1, ensuring that the prepolymer completely covers the target area and the LIG pattern. Then, place the entire assembly in a 60°C oven for curing for 30 minutes. After curing, cool to room temperature. Due to the weak adhesion between LIG and the PI substrate, but the strong interfacial bonding with Ecoflex, the cured Ecoflex film can be gently peeled off from the multilayer substrate. During this process, the LIG pattern is effectively transferred from the PI surface to the Ecoflex elastomer film, thereby forming a flexible LIG / Ecoflex composite electrode with a total thickness of approximately 375 μm.

[0063] The resistivity of the Ecoflex / LIG composite electrode is the primary indicator determining the performance of self-driven sensors, and its optimization must focus on CO2 laser engraving parameters. Experiments show that laser power, scan rate, and engraving resolution (PPI) have coupled effects on the degree of graphene formation and the continuity of the conductive network; in addition, the relative orientation of the scan direction and the expected current path also significantly changes the sheet resistance—when the laser trajectory is parallel to the current direction, the resulting resistance value is about 12% lower than that of the perpendicular orientation. Accordingly, the electrode pins are arranged in the same direction as the conductive channels during the layout design stage to reduce series impedance.

[0064] While maintaining the scanning direction parallel to the conductive channel, the engraving resolution was fixed at 1000 PPI. The effects of different power-speed combinations on surface resistivity were investigated, with 500 PPI serving as a control. The experimental platform used a VLS6.75 CO2 laser engraving machine rated at 50W, with a maximum tip movement speed of 1.27 ms⁻¹. Initial conditions were set to generate an effective LIG with a power of 2.5 W (5% of rated value) and a speed of 88.9 mm s⁻¹ (7% of maximum value). Given the significant process fluctuations in the low-power region, a non-linear incremental speed step was adopted before the power reached 8.5 W (17% of rated value). After multiple iterations, the optimal parameter combination balancing low resistivity and high consistency was obtained, as detailed in Table 1.

[0065] Table 1. Engraving Parameter Diagram

[0066]

[0067] like Figure 3As shown, using a Keithley 2450 precision source measurement unit, the resistivity of the Ecoflex / LIG composite electrode was recorded under different laser power-scan rate combinations. The test results show that when the engraving power is in the 20%–35% range, a significant low-value band appears in the material resistivity (…). Figure 4 Among them, the sixth group of parameters (laser power 32%) corresponds to the lowest values: 5.12 kΩ cm⁻¹ along the scanning direction and 5.87 kΩ cm⁻¹ in the vertical direction. Subsequently, the effect of engraving resolution on resistance was further examined. PPI is defined as the longitudinal spacing between two adjacent scan lines of the laser, in pixels per inch, and the pixel length is determined by the engineering drawing reference.

[0068] Reducing the resolution from 1000 PPI to 500 PPI while keeping power and speed constant yields the following results: Figure 5 , 6 As shown. Under 500 PPI conditions, a low-resistance plateau also appears in the 20%–35% engraving power range, reaching an extreme value at 32% power: 3.22 kΩ cm⁻¹ along the scanning direction and 6.07 kΩ cm⁻¹ in the vertical direction. These differences can be attributed to energy distribution reconstruction caused by resolution variations. Lower resolution increases the spacing between adjacent scans, reducing the probability of secondary ablation of the formed LIG and making the conductive network in the parallel direction more continuous, thus decreasing the resistance in that direction. However, the larger row spacing weakens the fiber density in the vertical direction, leading to a significant increase in the resistance difference between the two orthogonal directions. Due to the strong van der Waals forces, the pure Ecoflex surface is prone to adhesion to other materials during contact-separation, hindering device springback and causing functional failure. To address this issue, step 3 is introduced.

[0069] Step 3: Deposit a high-entropy energy material thin film on the surface of the LIG / Ecoflex composite electrode using magnetron sputtering to enhance the surface charge density and electron delocalization effect of the composite electrode. Specifically, this includes:

[0070] A 2 mm thick PMMA substrate was laser-cut to prepare a mask. Then, a 25 μm thick FEP film was laser-cut to prepare a film substrate of the same size as the mask. The LIG / Ecoflex composite electrode obtained in step 2 was used as the substrate and fixed on the sample stage of a magnetron sputtering apparatus. After evacuating the sputtering chamber to a high vacuum, argon gas at a flow rate of 25 sccm was introduced as the working gas to maintain the chamber pressure at 0.6 Pa. A high-entropy alloy target (e.g., equiatomic CoCrFeNiMn) was used for sputtering deposition at an excitation current of 0.2 A and a substrate bias voltage of 50 V, while maintaining the substrate temperature at 25°C. By controlling the sputtering time, a high-entropy energy material film with a uniform thickness of approximately 400 nm was prepared on the LIG surface. This film, combined with the three-dimensional porous structure of LIG, constitutes a composite friction layer with a synergistic enhancement effect, namely the high-entropy energy material / LIG / Ecoflex composite electrode.

[0071] like Figure 7 , 8 The results show that after HEA sputtering, the sheet resistance of LIG is significantly reduced, with the optimal value still falling at 32% laser power. At 1000 PPI, the horizontal and vertical resistivities corresponding to this power are 1.84 kΩ cm⁻¹ and 2.07 kΩ cm⁻¹, respectively. Therefore, the LIG / Ecoflex composite thin films used in the fabricated TENG devices uniformly adopt parameter group 6: laser power 32%, scan rate 60%.

[0072] To further evaluate the impact of engraving resolution on charge transfer efficiency, LIG ​​samples prepared with 27% laser power were selected. Starting from 200 PPI, the power was increased in increments of 200 PPI up to the upper limit of 1000 PPI, and the single-cycle charge amount of the LIG samples and FEP samples was measured. Figure 9 The results show that the charge difference among the five resolutions is only 2.3 nC, which is much smaller than the modulation amplitude of the square resistance by the PPI. Among them, the 600 PPI and 1000 PPI samples performed best, with charge amounts reaching 82.53 nC and 82.13 nC, respectively. Subsequent processes will combine layout complexity and processing efficiency, selecting the optimal option.

[0073] Step 4: Assemble the high-entropy energy material / LIG / Ecoflex composite electrode with other components to form a complete underwater TENG device.

[0074] like Figure 10 As shown, the underwater TENG device assembled in this embodiment of the invention adopts a sandwich layered structure, including:

[0075] The top layer is the high-entropy energy material / LIG / Ecoflex composite electrode layer prepared in step 3.

[0076] The middle layer is a 4mm thick polylactic acid (PLA) planar spring structure layer 3D printed. Its core function is to support the upper composite electrode and buffer the periodic water pressure load through its elastic deformation, converting vertical pressure into horizontal deformation, thus cleverly maintaining an effective contact-separation distance between the electrodes and solving the problem of instability of traditional TENGs under hydrostatic pressure. Below is a 2mm thick PLA substrate with many holes to amplify sound waves. A 25μm thick fluorinated ethylene propylene copolymer (FEP) film is bonded to it using aluminum double-sided adhesive tape as a negatively charged triboelectric layer. Patterned silver electrodes have been fabricated on the surface of this FEP film using a mask sputtering process to enhance charge transfer.

[0077] The bottom layer is a 3D-printed cylindrical cavity with a diameter of 80 mm, used to adjust the acoustic-mechanical resonance characteristics.

[0078] The top-layer high-entropy energy material / LIG / Ecoflex composite electrode layer is bridged to external conductors via nickel-plated copper foil conductive tape; the silver electrode of the lower FEP film is connected to external conductors via aluminum conductive tape, enabling effective acquisition of the output signal. Finally, waterproof polyurethane (PU) tape is used to rigorously seal the sides and interfaces of the entire device to ensure its long-term stable operation in underwater environments.

[0079] Example 2:

[0080] This invention proposes a self-driven underwater acoustic communication system, such as... Figure 11 As shown, it includes the sending end and the receiving end.

[0081] Transmitter: Using an STM32 series microcontroller as the core of the transmitter, the original text or image information to be transmitted is converted into a binary sequence (such as "0" and "1") according to the ASCII encoding method. Then, this binary sequence is mapped to two different frequency acoustic signals ("0" corresponds to 30Hz, and "1" corresponds to 60Hz). After being amplified by a power amplifier circuit, the acoustic signals drive the transmitting transducer to generate corresponding low-frequency sound waves in the water.

[0082] Energy harvesting and signal sensing: The emitted low-frequency sound waves act on the underwater TENG device prepared in Example 1. As a self-driven sensor, the underwater TENG device generates an alternating electrical signal corresponding to the sound wave frequency through the contact-separation of its internal composite electrode and the FEP film under water pressure fluctuations.

[0083] Receiver: The weak electrical signal generated by the underwater TENG device is first filtered and amplified by the acquisition circuit to condition the signal to a suitable processing level. The conditioned signal is then sent to the receiver's microprocessor, where it is demodulated according to the same encoding protocol as the transmitter. The 30Hz and 60Hz signals are identified as "0" and "1" respectively, the binary sequence is reconstructed, and finally restored to the original text or image information, which is then displayed on the screen or host computer software, completing the entire underwater self-driven communication process.

[0084] To evaluate the feasibility and stability of this device in underwater communication scenarios, a system is now constructed as follows: Figure 9 The water tank experimental platform is shown. A standard sinusoidal drive signal is amplified by a power amplifier and then fed into an underwater speaker; the sound wave propagates in the water and is captured by an underwater TENG device, which then outputs an electrical signal of the same frequency. After being conditioned by the acquisition circuit, the open-circuit voltage of this electrical signal is recorded and stored in real time by a digital oscilloscope.

[0085] To fully verify the effectiveness and reliability of the self-driven underwater acoustic communication system proposed in this embodiment of the invention, the underwater TENG device and the underwater communication system were jointly debugged and tested in a laboratory water tank simulating a real environment.

[0086] The underwater TENG device and receiver signal conditioning circuit were fixed at one end of the water tank, while the sound source at the transmitter was placed at the other end. First, in static water, a commercial hydrophone and signal analyzer were used to calibrate the 30Hz and 60Hz dual-frequency sound signals emitted by the transmitter, ensuring accurate frequency, clear waveform, and harmonic distortion below 3%. Then, without applying a communication signal, the output of the underwater TENG device under its own noise floor was recorded. Its peak output voltage was below 5mV, indicating that the device has a good signal-to-noise ratio.

[0087] Text transmission test: The sending end sends a predefined text message, such as "HELLO," in ASCII encoding. The receiving end successfully receives and demodulates the signal, such as... Figure 13 As shown.

[0088] Complex Information Transmission Test: To further verify the system's robustness, longer sentences and complex text containing numbers and symbols were transmitted. For example... Figure 14 As shown, although there are signal amplitude fluctuations caused by channel noise during transmission, the frequency detection-based demodulation algorithm can accurately distinguish between the two frequencies and ultimately decode all characters without error.

[0089] Figure 13 and Figure 14The experimental results and data clearly demonstrate that the underwater low-frequency self-driven acoustic sensor and its communication system based on high-entropy energy constructed in this invention can effectively and reliably transmit underwater text information. This system successfully integrates energy harvesting and information communication, not only verifying the correctness of its working principle but also demonstrating its enormous application potential in solving the energy bottleneck of underwater equipment and achieving long-term self-driven monitoring and communication.

Claims

1. An underwater triboelectric nanogenerator device, characterized in that: From top to bottom, it includes: a high-entropy energy material / LIG / Ecoflex composite electrode layer as the top layer, an intermediate layer to support the top layer, and a bottom layer to adjust the acoustic-mechanical resonance characteristics; The high-entropy energy material / LIG / Ecoflex composite electrode layer comprises, from top to bottom: a high-entropy energy material film, a laser-induced graphene pattern, and an Ecoflex elastomer film; the laser-induced graphene pattern is located on the surface of the Ecoflex elastomer film, and the high-entropy energy material film is deposited on the surface of the laser-induced graphene pattern by magnetron sputtering technology.

2. The underwater triboelectric nanogenerator device according to claim 1, characterized in that: The intermediate layer comprises, from top to bottom: a planar spring structure layer, a fluorinated ethylene propylene copolymer film with silver electrodes, and a polylactic acid substrate; the planar spring structure layer converts vertical water pressure into horizontal deformation through its elastic structure.

3. A self-driven underwater acoustic communication system, characterized in that: Includes a transmitter, an underwater triboelectric nanogenerator device, and a receiver; The transmitting end includes: a microcontroller, a power amplifier circuit, and a transmitting transducer; wherein, the microcontroller is used to convert the original text or image information to be transmitted into a binary sequence according to an encoding protocol, and then map the binary sequence into two different frequency sound signals; the power amplifier circuit is used to amplify the sound signals, and the transmitting transducer is used to generate corresponding sound waves in water based on the amplified sound signals; The underwater triboelectric nanogenerator device is an underwater triboelectric nanogenerator device as described in claim 1 or 2, used to generate an alternating electrical signal corresponding to the frequency of the sound wave generated at the transmitting end. The receiving end includes: a data acquisition circuit and a microprocessor; the data acquisition circuit is used to filter and amplify the alternating electrical signal generated by the underwater triboelectric nanogenerator device; the microprocessor is used to demodulate the electrical signal generated by the data acquisition circuit according to the same encoding protocol as the transmitting end, reconstruct the binary sequence, and finally restore it to the original text or image information.

4. A method for fabricating an underwater triboelectric nanogenerator device, characterized in that: Includes the following steps: Laser-induced graphene patterns were prepared using a layered stacking and selective laser processing method. Laser-induced graphene patterns were completely transferred into a flexible elastomer to obtain a flexible LIG / Ecoflex composite electrode. A high-entropy energy material / LIG / Ecoflex composite electrode was obtained by depositing a high-entropy energy material / LIG / Ecoflex composite electrode on the surface of a LIG / Ecoflex composite electrode using magnetron sputtering technology. A high-entropy energy material / LIG / Ecoflex composite electrode is used as the top layer to form an underwater triboelectric nanogenerator device.

5. The method for fabricating an underwater triboelectric nanogenerator device according to claim 1, characterized in that: The method employs layered stacking and selective laser processing to prepare laser-induced graphene patterns, including: The base layer is obtained by sequentially layering and pasting the bottom adhesive layer, polyimide film, paper tape layer, intermediate adhesive layer and polypropylene film; Laser cutting is performed along a predetermined path, with the cutting depth required to penetrate the polypropylene film, intermediate adhesive layer, paper tape layer, and extend into the polyimide film. After cutting, the polypropylene film, intermediate adhesive layer, and paper tape layer within the laser-cut area are manually peeled off and removed to expose the surface of the underlying polyimide film, forming the desired height difference structure. By utilizing the thermal effect of lasers, the exposed surface of polyimide films is transformed into porous graphene structures, forming laser-induced graphene patterns.

6. The method for fabricating an underwater triboelectric nanogenerator device according to claim 2, characterized in that: The process of completely transferring a laser-induced graphene pattern into a flexible elastomer to obtain a flexible LIG / Ecoflex composite electrode includes: Weigh component A and component B of Ecoflex 00-50 precisely at a mass ratio of 1:1, pour them into a mixing container and stir until the mixture is homogeneous and free of visible streaks. The uniformly mixed prepolymer is degassed. The degassed prepolymer is poured onto the laser-induced graphene pattern, ensuring that the prepolymer completely covers the target area and the laser-induced graphene pattern, and then cured as a whole. After curing, the cured Ecoflex film is peeled off from the substrate. During this process, the laser-induced graphene pattern is completely transferred and embedded into the Ecoflex film to form a flexible LIG / Ecoflex composite electrode.

7. The method for fabricating an underwater triboelectric nanogenerator device according to claim 6, characterized in that: The high-entropy energy material / LIG / Ecoflex composite electrode is obtained by depositing a high-entropy energy material / LIG / Ecoflex composite electrode on the surface of the LIG / Ecoflex composite electrode using magnetron sputtering technology, including: Using a LIG / Ecoflex composite electrode as a substrate, sputtering deposition was performed using a high-entropy alloy target. By controlling the sputtering time, a high-entropy energy material film with uniform thickness was prepared on the surface of the laser-induced graphene pattern. This high-entropy energy material film was combined with the three-dimensional porous structure of the laser-induced graphene pattern to obtain the high-entropy energy material / LIG / Ecoflex composite electrode.

8. The method for fabricating an underwater triboelectric nanogenerator device according to claim 1, characterized in that: The underwater triboelectric nanogenerator device, which uses a high-entropy energy material / LIG / Ecoflex composite electrode as the top layer, includes a high-entropy energy material / LIG / Ecoflex composite electrode layer as the top layer, an intermediate layer for supporting the top layer, and a bottom layer for adjusting the acoustic-mechanical resonance characteristics. The intermediate layer, from top to bottom, comprises: a planar spring structure layer, a fluorinated ethylene propylene copolymer film with silver electrodes, and a polylactic acid substrate; The planar spring structure layer converts vertical water pressure into horizontal deformation through its elastic structure. The high-entropy energy material / LIG / Ecoflex composite electrode is bridged to the external wires via nickel-plated copper foil conductive tape, and the silver electrode of the fluorinated ethylene propylene copolymer film is connected to the external wires via aluminum conductive tape, thereby achieving effective acquisition of the output signal. The sides and interfaces of the entire device are sealed and encapsulated using waterproof polyurethane tape.

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