Dual-mode friction nano generator based on laser-induced graphene

Abstract

The invention discloses a dual-mode friction nano generator based on laser-induced graphene, and relates to the technical field of energy collection, the dual-mode friction nano generator comprises a base, a supporting plate is fixedly connected to the base, a groove is formed in a swing rod, a film is fixedly connected to the bottom of the groove of the swing rod, an interdigital electrode is arranged on the film, and a small ball is placed in the groove. The friction layers A are fixedly connected to the left side and the right side of the bottom face of the swing rod, electrodes A are arranged on the friction layers A, the friction layers B are fixedly connected to the base, and electrodes B are arranged on the friction layers B; the waterproof cover is buckled above the supporting plate, and the bottom end face of the waterproof cover is attached to the upper surface of the base. The pin is rotationally connected into the circular through holes of the waterproof cover, the supporting plate and the swing rod, it is ensured that the swing rod can swing left and right around the pin, the vertical contact separation type working mode and the independent layer type working mode are integrated, and therefore low-frequency wave energy is effectively utilized, mechanical energy is better collected, and the mechanical energy utilization rate is improved. And the working efficiency of the friction nanometer generator is further improved.

Description

Technical Field

[0001] The present invention relates to the technical field of energy collection, and in particular to a dual-mode friction nanogenerator based on laser-induced graphene for wave energy collection. Background Art

[0002] In recent years, new clean energy sources, particularly the efficient conversion of tiny amounts of mechanical energy in the environment into electrical energy, have become a research hotspot. Ocean wave and tidal energy, with their wide distribution, long availability, and vast potential, are among the cleanest renewable energy sources. Rationally utilizing wave energy in the vast oceans is a key component of sustainable development strategies and can guide the development and utilization of new energy sources.

[0003] Currently, wave energy harvesting primarily relies on electromagnetic generators (EMGs) to absorb and convert mechanical energy. However, the low frequency (<3 Hz) and disorder of waves prevent EMGs from efficiently collecting and converting wave energy. Furthermore, EMG-based energy harvesting devices are generally large and expensive. In contrast, triboelectric nanogenerators (TENGs) have a wider operating frequency range, maintaining high output efficiency even for vibrations below 5 Hz. Furthermore, TENGs can provide stable output even under waves with high spatiotemporal variability. Furthermore, TENGs are inexpensive to manufacture, making them well-suited for efficient wave energy harvesting via large-scale TENG networks.

[0004] However, the energy density of current TENGs remains low, and there is an urgent need to increase their output power through material innovation and structural optimization. Multimode TENGs, by combining multiple operating modes, can more efficiently capture vibration energy, significantly improving the universality of energy harvesting. Furthermore, through the synergistic effects of multiple operating modes, higher output voltage, current, and power density can be achieved. Currently, multimode triboelectric nanogenerators generally suffer from complex structures, poor environmental adaptability, and complex and time-consuming preparation processes.

[0005] TENG devices primarily consist of active materials that generate charge and conductive electrodes that transport the generated charge. Laser-induced graphene (LIG) is gaining increasing attention as a highly efficient TENG electrode material due to its high conductivity, three-dimensional porous structure, and excellent stability. Importantly, LIG ​​can be directly fabricated on the surfaces of dielectric and triboelectric materials (such as polyimide or paper substrates), thereby forming an integrated TENG device. Using LIG electrodes instead of traditional metal electrodes significantly simplifies the TENG structure and fabrication process, facilitates the integration of TENGs in various modes, and significantly reduces manufacturing costs.

[0006] Therefore, the development of a dual-mode triboelectric nanogenerator based on laser-induced graphene for wave energy harvesting will help improve the energy harvesting efficiency and energy density of TENG, which is of great significance to the realization of the development goal of green energy. Summary of the Invention

[0007] The technical problem to be solved by the present invention is to provide a dual-mode friction nanogenerator based on laser-induced graphene, which combines the two working modes of vertical contact separation and independent layer, thereby effectively utilizing low-frequency wave energy, better collecting mechanical energy, and further improving the working efficiency of the friction nanogenerator.

[0008] A dual-mode triboelectric nanogenerator based on laser-induced graphene, comprising a waterproof cover, a small ball, a film, interdigital electrodes, a swing rod, two friction layers A, two electrodes A, two friction layers B, two electrodes B, two support plates, a pin and a base; A support plate is fixedly connected to the base; Circular through holes are opened at the front and rear of the support plate; A groove is provided in the swing rod, and a circular through hole is provided in the center of the bottom of the front and rear surfaces of the swing rod; The film is fixed to the bottom of the swing rod groove, and there are interdigital electrodes on the film. A small ball is placed in the groove, and the ball can roll left and right in the groove; The two friction layers A are symmetrically fixed to the left and right sides of the bottom surface of the swing rod. Each friction layer A is provided with an electrode A on the side close to the swing rod. The two friction layers B are fixed to the projections of the two friction layers A on the upper surface of the base. Each friction layer B is provided with an electrode B on the side close to the base. A circular through hole is provided on the waterproof cover, the waterproof cover is buckled on the support plate and the bottom end surface of the waterproof cover is in contact with the upper surface of the base; The pin is rotatably connected in the circular through hole of the waterproof cover, the support plate and the swing rod, ensuring that the swing rod can swing left and right around the pin.

[0009] Preferably, the materials of the friction layer A and the film are both polyimide films, and the materials of the electrode A, the electrode B and the interdigital electrodes are all laser-induced graphene; The material of friction layer B is polydimethylsiloxane.

[0010] Preferably, the specific method for generating electrode A on friction layer A is as follows: select a high-temperature resistant glass slide, wipe it clean with anhydrous ethanol, and use double-sided tape to stick a 200 μm thick polyimide film on the glass slide, press the polyimide film hard to empty the bubbles between the polyimide film and the colloid, set the laser parameters, the Q wave pulse frequency is 200 kHz, the scanning speed is set to 50 mm / s, and the pulse width is 15 ns. Use an ultrasonic cleaner to clean the sample to remove surface oil, then place the sample under the ultraviolet laser spot, adjust the sample to 18.90 mm from the focus of the laser lens, use drawing software to draw a rectangular electrode pattern, and use a laser to complete pattern printing.

[0011] Preferably, the shape of the interdigitated electrodes is an interdigitated grid electrode pattern.

[0012] Preferably, the specific method for forming the electrode B on the friction layer B is as follows: First, electrode B is generated on the polyimide film; Next, transfer electrode B from the polyimide film using the following method: The polyimide film with electrode B was fixed to the bottom of the mold using heat-resistant 3M glue. The polydimethylsiloxane solution and the curing agent were mixed and stirred in a ratio of 10:1, and then poured onto the mold. The mold was placed in a vacuum machine and vacuumed at a negative pressure of 0.8 MPa for 30 minutes to remove the bubbles in the polydimethylsiloxane after stirring and the gas that was not completely exhausted in the contact area between the liquid polydimethylsiloxane and the laser-induced graphene sample. When there were no visible bubbles on the surface of the liquid polydimethylsiloxane, the mold was placed in a dryer and heated at 120°C for 90 minutes to cure the polydimethylsiloxane and transfer the graphene. After heating, the polyimide film was peeled off to obtain a single-layer flexible polydimethylsiloxane-laser-induced graphene.

[0013] Preferably, the base and the swing arm are made of resin material.

[0014] The beneficial effects of the present invention are: Referring to the working principle of the seesaw, the vertical contact separation mode and the independent layer mode are integrated together to effectively utilize low-frequency wave energy, better collect mechanical energy, and further improve the working efficiency of the friction nanogenerator; The friction layer is made of two flexible materials, polyimide and polydimethylsiloxane. The laser-induced graphene used as the electrode is also a flexible two-dimensional material. The materials used have good stability and can be used in humid marine environments, which makes the overall dual-mode friction nanogenerator component have a longer service life and broadens the application field of two-dimensional materials. At the same time, laser-induced graphene can be directly generated by laser processing of the friction layer material polyimide film, and can be transferred to another friction layer material polydimethylsiloxane. It has the advantages of simple preparation, designable pattern, green and environmental protection, low cost, large specific surface area, and thus improved voltage and power density. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a structural schematic diagram of the present invention; Figure 2 It is a structural schematic diagram of the waterproof cover of the present invention; Figure 3 is an exploded isometric view of the present invention; Figure 4 This is a top view of the present invention after removing the waterproof cover; Figure 5 Schematic diagram of the structure of polyimide film and interdigital electrodes; Figure 6 Schematic diagram of the structure of friction layer A, electrode A, friction layer B and electrode B; Figure 7 This is a working principle diagram of the contact-separation friction nanogenerator of the present invention; Figure 8 This is a working principle diagram of the independent layer-type tribonanogenerator of the present invention; Figure 9 This is the circuit diagram inside the dual-mode friction nanogenerator.

[0016] In the figure: 1-waterproof cover, 2-small ball, 3-film, 4-interdigitated electrode, 5-swing rod, 6-friction layer A, 7-electrode A, 8-friction layer B, 9-electrode B, 10-support plate, 11-pin, 12-base. DETAILED DESCRIPTION

[0017] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without creative work are within the scope of protection of the present invention.

[0018] like Figures 1 to 8As shown, a dual-mode triboelectric nanogenerator based on laser-induced graphene includes a waterproof cover 1, a ball 2, a film 3, an interdigital electrode 4, a swing rod 5, two friction layers A6, two electrodes A7, two friction layers B8, two electrodes B9, two support plates 10, a pin 11 and a base 12; The base 12 is made of resin material by additive manufacturing technology. Two symmetrical embedded grooves are provided on the base 12 for embedding the support plate 10. The support plates 10 are made of resin material through additive manufacturing technology. The two support plates 10 are symmetrically embedded in the embedded grooves on the base 12. The top of the support plate 10 is provided with a slot for fixing the swing rod 5. The front and back of the support plate 10 are provided with circular through holes for the pin 11 to penetrate. The swing lever 5 is made of resin material using additive manufacturing technology. A groove is formed inside the swing lever 5. A circular through hole is formed in the center of the bottom of the front and rear surfaces of the swing lever 5 for the pin 11 to pass through. The swing lever 5 is installed between the two support plates 10, ensuring that the circular through hole of the swing lever 5 is aligned with the circular through hole on the support plate 10. like Figure 4 As shown, a double-sided tape is used to fix the film 3 to the bottom of the groove of the swing rod 5. The film 3 is provided with an interdigital electrode 4. A small ball 2 is placed in the groove, and the ball 2 can roll left and right in the groove. like Figure 6 As shown, two friction layers A6 are symmetrically fixed to the left and right sides of the bottom surface of the swing rod 5 using double-sided tape, and an electrode A7 is provided on the side of each friction layer A6 close to the swing rod 5. Two friction layers B8 are fixed to the projections of the two friction layers A6 on the upper surface of the base 12 using double-sided tape, and an electrode B9 is provided on the side of each friction layer B8 close to the base 12. like Figures 1 to 3 As shown, the waterproof cover 1 is made of acrylic material to ensure that it is lightweight, waterproof, and has good light transmittance, which is convenient for observing the internal movement. A circular through hole is opened on the waterproof cover 1 for the pin 11 to penetrate. A card slot is opened in the middle of the bottom end of the front and back sides of the waterproof cover 1. Ensure that the card slot matches the slot on the support plate 10. Buckle the waterproof cover 1 in the slot above the support plate 10, and the bottom end surface of the waterproof cover 1 is in contact with the upper surface of the base 12; at the same time, ensure that the circular through hole of the waterproof cover 1 is aligned with the circular through hole of the support plate 10; The pin 11 is rotatably connected to the circular through hole of the waterproof cover 1, the support plate 10, and the swing rod 5, ensuring that the swing rod 5 can swing left and right around the pin 11; like Figure 3 、 Figure 5 As shown, the materials of the friction layer A6 and the film 3 are both polyimide films, and the materials of the electrode A7 and the interdigital electrode 4 are both laser-induced graphene. The electrode A7 and the interdigital electrode 4 are directly generated on the friction layer A6 and the film 3 using a laser; The specific method for generating electrode A7 is as follows: select a high-temperature resistant glass slide, wipe it clean with anhydrous ethanol, and use double-sided tape to stick a 200μm thick polyimide film on the glass slide, press the polyimide film hard to empty the bubbles between the polyimide film and the colloid, prevent the bulges caused by the bubbles from interfering with the focal length during laser scanning, and avoid uneven laser ablation resulting in unstable performance of the generated graphene, set the laser parameters, Q wave pulse frequency to 200kHz, scanning speed to 50mm / s, pulse width to 15ns, use an ultrasonic cleaner to clean the sample to remove surface oil, then place the sample under the ultraviolet laser spot, adjust the sample to 18.90mm from the focus of the laser lens, use drawing software to draw a rectangular electrode pattern, and use a laser to complete pattern printing; The material of electrode B9 is also laser-induced graphene, and the processing method is the same as above; Similarly, the specific method of generating the interdigital electrode 4 is the same as that of the electrode A7, except that the rectangular electrode pattern is replaced with an interdigital grid electrode pattern; The friction layer B8 is made of polydimethylsiloxane. First, the electrode B9 needs to be transferred from the polyimide film. The transfer method is as follows: The polyimide film with electrode B9 was fixed to the bottom of the mold using heat-resistant 3M glue. The polydimethylsiloxane solution and the curing agent were mixed and stirred in a ratio of approximately 10:1, and then poured onto the mold. The mold was placed in a vacuum machine and evacuated at a negative pressure of 0.8 MPa for 30 minutes to remove the bubbles in the polydimethylsiloxane after stirring and the gas that was not completely discharged in the contact area between the liquid polydimethylsiloxane and the laser-induced graphene sample. When there were no visible bubbles on the surface of the liquid polydimethylsiloxane, the mold was placed in a dryer and heated at 120°C for 90 minutes to cure the polydimethylsiloxane and transfer the graphene. After heating, the polyimide film was peeled off to obtain a single-layer flexible polydimethylsiloxane-laser-induced graphene, that is, the electrode B9 was successfully prepared on the surface of the friction layer B8.

[0019] Working principle of the present invention: The working principle of contact-separation friction nanogenerator is as follows Figure 7 As shown in the figure, the friction layer A6 and the friction layer B8 contact each other under the action of external pressure. Due to the triboelectric effect, the surface charge (e) is transferred, so that the surfaces of the two materials are each charged with equal amounts of positive and negative charges (e), forming a potential difference. When the external pressure is released, the friction layer A6 and the friction layer B8 separate. Due to the existence of the potential difference, electrons flow from high potential to low potential through the external circuit to achieve charge (e) balance. When the external stress is applied again, the induced charge (e) will flow back to their initial electrodes, which will also generate a reverse current. When the contact and separation cycle is repeated, the friction nanogenerator can generate a periodic AC output. The working principle of the independent friction layer mode triboelectric nanogenerator is as follows Figure 8 As shown, the ball 2 and the film 3 are in contact in the air and carry an electric charge (e). The ball 2 acts as an independent friction layer and the film 3 acts as a sensing layer. The ball 2 rolls back and forth on the interdigitated electrodes 4, causing the charge (e) to change. An induced potential difference is formed between the two electrodes, driving the movement of electrons. The periodic rolling of the ball 2 causes the electrons to move periodically between the two electrodes, thereby generating an AC output.

[0020] like Figure 3 As shown, the device of the present invention is installed in a wave simulation device. When the device moves with the waves, the left and right ends of the swing rod 5 alternately contact the base 12, causing the contact-separation mode friction nanogenerators on both sides to alternately complete contact and separation, outputting electrical signals. At the same time, as the swing rod 5 swings left and right, the balls 2 in the grooves roll left and right, continuously passing through the interdigital electrodes 4, outputting electrical signals. The circuit connections inside the dual-mode triboelectric nanogenerator are as follows: Figure 9 As shown in the figure, where R represents resistance, it includes two contact-separation triboelectric nanogenerator units (V-TENG1 and V-TENG2) and an independent layer triboelectric nanogenerator unit (F-TENG). Each unit is connected to a full-wave rectifier bridge, which then charges the capacitor C to store electrical energy and finally powers the external load. When sufficient charge is accumulated, the energy can be distributed to the power supply device through a switch.

[0021] Through the above specific implementation methods, a contact-separation and independent layer dual-mode friction nanogenerator can be successfully manufactured and operated, which is suitable for environmental energy harvesting such as wave energy.

Claims

1. A dual-mode triboelectric nanogenerator based on laser-induced graphene, characterized by: It includes a waterproof cover (1), a small ball (2), a film (3), an interdigital electrode (4), a swing rod (5), two friction layers A (6), two electrodes A (7), two friction layers B (8), two electrodes B (9), two support plates (10), a pin (11) and a base (12); A support plate (10) is fixedly connected to the base (12); The support plate (10) has circular through holes at the front and rear; A groove is provided in the swing rod (5), and circular through holes are provided in the center of the bottom of the front and rear surfaces of the swing rod (5); The film (3) is fixedly connected to the bottom of the groove of the swing rod (5), and an interdigitated electrode (4) is provided on the film (3). A small ball (2) is placed in the groove, and the small ball (2) can roll left and right in the groove; Two friction layers A (6) are symmetrically fixed on the left and right sides of the bottom surface of the swing rod (5), and an electrode A (7) is provided on the side of each friction layer A (6) close to the swing rod (5). Two friction layers B (8) are fixed on the projections of the two friction layers A (6) on the upper surface of the base (12), and an electrode B (9) is provided on the side of each friction layer B (8) close to the base (12); A circular through hole is provided on the waterproof cover (1), the waterproof cover (1) is buckled on the support plate (10), and the bottom end surface of the waterproof cover (1) is in contact with the upper surface of the base (12); The pin (11) is rotatably connected to the circular through hole of the waterproof cover (1), the support plate (10), and the swing rod (5), ensuring that the swing rod (5) can swing left and right around the pin (11).

2. The dual-mode triboelectric nanogenerator based on laser-induced graphene according to claim 1, characterized in that: The materials of the friction layer A (6) and the film (3) are both polyimide films, and the materials of the electrode A (7), the electrode B (9) and the interdigital electrode (4) are all laser-induced graphene; The material of the friction layer B (8) is polydimethylsiloxane.

3. The dual-mode triboelectric nanogenerator based on laser-induced graphene according to claim 2, characterized in that: The specific method for generating the electrode A (7) on the friction layer A (6) is as follows: select a high-temperature resistant glass slide, wipe it clean with anhydrous ethanol, and use double-sided tape to stick a 200 μm thick polyimide film on the glass slide, press the polyimide film hard to empty the bubbles between the polyimide film and the colloid, set the laser parameters, the Q wave pulse frequency is 200 kHz, the scanning speed is set to 50 mm / s, and the pulse width is 15 ns. Use an ultrasonic cleaner to clean the sample to remove surface oil stains, then place the sample under the ultraviolet laser spot, adjust the sample to 18.90 mm from the focus of the laser lens, use drawing software to draw a rectangular electrode pattern, and use a laser to complete the pattern printing.

4. The dual-mode triboelectric nanogenerator based on laser-induced graphene according to claim 2, characterized in that: The shape of the interdigitated electrode (4) is an interdigitated grid electrode pattern.

5. The dual-mode triboelectric nanogenerator based on laser-induced graphene according to claim 3, characterized in that: The specific method of forming the electrode B (9) on the friction layer B (8) is as follows: First, electrode B (9) is formed on the polyimide film; Next, the electrode B (9) is transferred from the polyimide film using the following method: The polyimide film with electrode B (9) was fixed to the bottom of the mold using heat-resistant 3M glue, and polydimethylsiloxane solution and curing agent were mixed and stirred in a ratio of 10:1, and poured on the mold. The mold was placed in a vacuum machine and vacuumed at a negative pressure of 0.8 MPa for 30 minutes to remove the bubbles in the polydimethylsiloxane after stirring and the gas that was not completely exhausted in the contact area between the liquid polydimethylsiloxane and the laser-induced graphene sample. When there were no visible bubbles on the surface of the liquid polydimethylsiloxane, the mold was placed in a dryer and heated at 120°C for 90 minutes to cure the polydimethylsiloxane and transfer the graphene. After heating, the polyimide film was peeled off to obtain a single layer of flexible polydimethylsiloxane-laser-induced graphene.

6. The dual-mode triboelectric nanogenerator based on laser-induced graphene according to claim 1, characterized in that: The material used for the base (12) and the swing rod (5) is a resin material.

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