Double-layer interdigital frictional nanogenerator

Abstract

The application discloses a double-layer staggered chain tooth type friction nanogenerator which is composed of a plurality of units and a frame, each unit of the plurality of units is composed of a plurality of chain teeth made of acrylic plates, copper films are plated on the chain teeth to serve as electrodes of the friction nanogenerator, the frame is made of acrylic material, sponge is attached to the surface of the frame, and polyimide film is attached to the sponge to serve as an independent layer. The double-layer staggered chain tooth type friction nanogenerator can convert mechanical energy from linear or rotary mechanical movement into electrical energy, is a sustainable energy source, and can be combined with a zipper structure. Compared with a traditional zipper, the double-layer staggered chain tooth type friction nanogenerator can generate electrical energy in the continuous pulling process of the zipper, the generated electrical energy can light up more than 15 LED lamps after rectification, and can also power electronic equipment.

Description

Technical Field

[0001] This invention relates to the field of nanogenerator technology, specifically a double-layered interlaced chain tooth triboelectric nanogenerator. Background Technology

[0002] Nanogenerators, based on regular zinc oxide nanowires, convert mechanical energy into electrical energy within the nanometer range. They are the smallest generators in the world. Currently, nanogenerators can be divided into three categories: piezoelectric nanogenerators, which utilize the piezoelectric and semiconductor properties of special nanomaterials to convert mechanical energy from bending and compression into electrical energy; triboelectric nanogenerators, which utilize two materials with different electron-binding abilities to generate current in an external circuit by gaining and losing electrons when they come into contact; and pyroelectric nanogenerators.

[0003] However, existing triboelectric nanogenerators are difficult to integrate with real-world objects to achieve triboelectric power generation, resulting in a narrow range of applications. Due to the increasing scarcity of electricity in society, triboelectric nanogenerators are unlikely to be used as a sustainable energy source in daily life. Summary of the Invention

[0004] The purpose of this invention is to provide a double-layered interlaced chain tooth triboelectric nanogenerator to solve the problems mentioned in the background art, such as the difficulty in combining existing triboelectric nanogenerators with real-life objects to achieve triboelectric power generation, the narrow scope of application, and the difficulty in using triboelectric nanogenerators as a sustainable energy source in daily life due to the increasing scarcity of electricity in society.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a double-layer interlaced chain tooth triboelectric nanogenerator, which consists of multiple units and a frame. Each of the multiple units consists of several chain teeth made of acrylic plates. The chain teeth are coated with copper film to serve as electrodes of the triboelectric nanogenerator. The frame is made of acrylic material, and a sponge is attached to the surface of the frame. A polyimide film is attached to the sponge to serve as an independent layer.

[0006] Preferably, the main purpose of attaching sponge to the frame surface is to increase the close contact between the polyimide and the electrode, so that the independent layer can be in close contact with the electrode and obtain a greater output effect.

[0007] Preferably, the unit follows the principle of independent mode operation. Compared with the double-layer staggered electrode triboelectric nanogenerator, the output effect of the double-layer staggered chain tooth triboelectric nanogenerator is slightly smaller.

[0008] Compared with existing technologies, the beneficial effects of this invention are as follows: This double-layer interlaced chain tooth triboelectric nanogenerator can convert mechanical energy from linear or rotational mechanical motion into electrical energy, which is a sustainable energy source. The double-layer interlaced chain tooth triboelectric nanogenerator can be combined with a zipper structure. Compared with traditional zippers, the double-layer interlaced chain tooth triboelectric nanogenerator can generate electrical energy during the continuous pulling of the zipper. After rectification, the generated electrical energy can light more than 15 LEDs and can also power electronic devices. Through the chain tooth array, the open-circuit voltage and transferred charge generated during continuous pulling of the zipper are improved. The double-layer interlaced chain tooth triboelectric nanogenerator has a good application environment in daily life. When people encounter a power outage outdoors, they can pull the zipper to make the double-layer interlaced chain tooth triboelectric nanogenerator work to charge the internally connected capacitor. The electricity charged by the capacitor can be used in emergencies. Attached Figure Description

[0009] Figure 1(a) shows the independent layer mode triboelectric nanogenerator model of the present invention;

[0010] Figure 1(b) shows the output voltage image simulated by COMSOL when the independent layer of the present invention moves to the right;

[0011] Figure 2 This is a schematic diagram of the double-layered interlaced chain tooth triboelectric nanogenerator of the present invention;

[0012] Figure 3 (a) is a schematic diagram of the interleaved electrode triboelectric nanogenerator lattice of the present invention;

[0013] Figure 3 (b) is a schematic diagram of the electrode connection between the staggered electrode triboelectric nanogenerator of the present invention and the independent layer;

[0014] Figure 3 (c) in the figure represents the voltage change curve of an independent layer motion cycle in one cycle of the present invention;

[0015] Figure 3 In the figure (d), the output voltage and output current curves change when the independent layer motion period of the present invention is 0.3s, 0.4s and 0.5s.

[0016] Figure 4 (a) in the figure is a schematic diagram and a physical image of the double-layer staggered electrode triboelectric nanogenerator of the present invention;

[0017] Figure 4 (b) shows the voltage variation curves of the double-layer staggered electrode triboelectric nanogenerator when the independent layer motion period is 0.3s, 0.4s, and 0.5s.

[0018] Figure 4(c) is a physical image of the interlaced chain tooth triboelectric nanogenerator of the present invention, which has metal teeth and acrylic teeth with copper film attached.

[0019] Figure 4 In the figure (d), the voltage change curve of the staggered chain tooth triboelectric nanogenerator with metal chain teeth and acrylic teeth attached to copper film is when the independent layer movement cycle is 0.5s.

[0020] Figure 5 (a) in the figure is the staggered chain tooth triboelectric nanogenerator of the present invention, with 2, 3 and 4 pairs of chain teeth respectively;

[0021] Figure 5 (b) in the figure shows that when the number of chain tooth pairs is 2, 3, or 4, the output voltage of the independent layer motion cycle is 0.5s.

[0022] Figure 5 (c) and (d) in the figure are a comparison of the output voltage and output current of the three triboelectric nanogenerators of the present invention;

[0023] Figure 6 In the figure, (a) represents the distance g between different electrodes of the double-layer interlaced chain tooth triboelectric nanogenerator of the present invention, and the distance between different chain teeth of the same electrode i.

[0024] Figure 6 (b) in the figure shows the relationship between the distance g between the electrodes and the output voltage in this invention;

[0025] Figure 6 (c) in the figure represents the relationship between the distance i between the same electrode and different chain teeth and the output voltage in this invention;

[0026] Figure 6 (d) in the figure is a schematic diagram of the commercial LED driving circuit of the present invention;

[0027] Figure 6 In the diagram (e), 15 LEDs are lit simultaneously in this invention. Detailed Implementation

[0028] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0029] Please refer to Figures 1-6. This invention provides a technical solution: a double-layer staggered chain tooth triboelectric nanogenerator, which consists of multiple units and a frame. Each unit consists of several chain teeth made of acrylic plates. The chain teeth are coated with copper film to serve as electrodes of the triboelectric nanogenerator. The frame is made of acrylic material, and a sponge is attached to the surface of the frame. A polyimide film is attached to the sponge to serve as an independent layer. The main purpose of attaching the sponge to the surface of the frame is to increase the close contact between the polyimide and the electrodes, so that the independent layers can have close contact with the electrodes and obtain a greater output effect. The units follow the working principle of independent mode. Compared with the double-layer staggered electrode triboelectric nanogenerator, the output effect of the double-layer staggered chain tooth triboelectric nanogenerator is slightly smaller.

[0030] The basic theoretical method of double-layer interlaced chain tooth triboelectric nanogenerator:

[0031] As shown in Figure 1(a), the left side of the independent layer first coincides with the left side of electrode 1. Let the distance the independent layer moves to the right be x(t) (x(t)≥0), the distance between the electrodes be g, the width of the electrode be m, and the distance from the electrode to the lower surface of the independent layer be h.

[0032] Assuming h = 0, and that only a small portion of dk on the dielectric surface of the bottom surface contains triboelectric charge with a charge density of -σ, the total charge on the left electrode 1 and the right electrode 2 is σmdk. The charges (dQ1 and dQ2) on electrodes 1 and 2 under short-circuit conditions can be represented by the following equation, C i (k) represents the capacitance between the small interface and electrode i:

[0033]

[0034]

[0035] According to the principle of superposition of electrostatic fields, considering that the total charge on the surface of a dielectric is the superposition of small electrostatic regions, the total charge of electrode 1 and electrode 2 can be expressed in the following form:

[0036]

[0037]

[0038] Therefore, Q sc,final It can be represented as

[0039]

[0040] When x = 0, the distance between the charged dielectric surface and electrode 1 is much smaller than the distance to electrode 2. Since the capacitance ratio is inversely proportional to the distance, for any value of k, the ratio of C2(k) / C1(k) is close to 0. Therefore, based on the total charge expression for electrodes 1 and 2, Q1 is approximately σml, and Q2 is approximately 0. Conversely, when x = g + l, the distance between the dielectric surface and electrode 2 is much smaller than the distance to electrode 1. Therefore, regardless of the value of k, C2(k) / C1(k) tends to infinity, Q1 is approximately 0, Q2 is approximately σml, and the charge transfer efficiency reaches 100%. Therefore, Q... sc,final Ultimately, σml can be achieved, where the changes in capacitance ratio and x are the driving force for the flow of electrons between the two electrodes.

[0041] Therefore, the maximum transferred charge Q sc,max Maximum open-circuit voltage V oc,max The relationship between the capacitance C0 formed between the electrodes and the following is as follows:

[0042] Q sc,max =C0V oc,max

[0043] As shown in Figure 1(b), the independent-layer mode triboelectric nanogenerator was simulated and analyzed using the finite element simulation software Comsol Multiphsics. The simulation verified the potential distribution of the triboelectric nanogenerator during operation. When the independent layer slides from left to right to completely cover the two metal electrodes, the maximum positive and negative potential differences between the two electrodes are obtained, respectively. When the independent layer does not contact the electrodes and is completely separated from them, the potential difference between the two electrodes is almost zero. When the independent layer slides over either electrode, all the charges on the electrode are shielded, so the maximum potential difference can be obtained between the two electrodes. When the independent layer does not contact the electrodes, the charges on the surfaces of the two electrodes are the same, so the potential difference between the two electrodes is almost zero. This simulation result is consistent with the theoretical analysis above.

[0044] Structure and basic principles of a double-layered interlaced chain tooth triboelectric nanogenerator:

[0045] The structure of one side of the double-layered interlaced chain tooth triboelectric nanogenerator is as follows: Figure 2As shown, the device mainly consists of two parts: an independent layer and interlaced teeth. The independent layer is divided into upper and lower parts, each with a layer of sponge about 1 mm thick on its surface. A layer of polyimide film is attached to the surface of the sponge as the independent layer material. The teeth shape is cut out of an acrylic plate, and a copper film is attached to one surface of the acrylic plate with the teeth shape. Wires are led out. Initially, four teeth on one side are covered by the independent layer, so the four teeth covered by the independent layer are used as an electrode. The working principle of the double-layer interlaced tooth triboelectric nanogenerator can be summarized as the combined effect of contact charge and in-plane sliding induced charge. Initially, the independent layer and the cross electrode group 1 (①③) (teeth) are in a position of complete overlap. Since the triboelectric polarity of the polyimide film is much different from that of copper, when the surface contacts and rubs, negative charges will accumulate on the surface of the independent layer, and positive charges will accumulate on the surface of electrode 1. The amount of positive and negative charges is equal. Figure 2 (a) is in electrostatic equilibrium, so there is no charge transfer in the circuit at this time. When the independent layer starts to slide horizontally from left to right, it moves from the position coinciding with the right electrode group 1 to the left to the electrode group 2 (②④)(chain teeth). In this state, the potential at ① is higher than that at ②, which will cause instantaneous electrons to move from ② to ①, and an instantaneous current is generated from ① to ②. When the independent layer continues to slide horizontally to the right, the potential difference between ① and ② gradually decreases until the potential difference at position (2) is zero. When the independent layer moves from the right to the left, it moves from the right to the left to ... Figure 2 (b) Movement to Figure 2 (c) During the positioning process, the potential at ② is higher than that at ①, until... Figure 2 (c) At position, all positive charges are transferred to electrode group 2, and the absolute value of the potential difference between ① and ② reaches its maximum value, forming another electrostatic equilibrium state in the circuit. When the independent layer slides horizontally to the right again, an instantaneous current is generated in the opposite direction to that in the previous stage. When the independent layer moves to coincide with ③, this is a cycle of power generation. This cycle first involves ① and ② working, and then ② and ③ working. The double-layered interlaced chain tooth triboelectric nanogenerator is composed of several such parts.

[0046] Results and discussion of a double-layered interlaced chain tooth triboelectric nanogenerator:

[0047] According to the design, the chain teeth have two surfaces, one positive and one negative. The surface area of ​​the chain teeth is approximately 2A (210mm²). 2 The surface area of ​​the 8 chain teeth is 16A (1680 mm²). 2 Using 32 chain teeth as the experimental subject, the surface area covered by the chain teeth during movement of the independent layer was 1680 mm². 2 (32mm × 52.5mm), the covered area is used as one electrode of the triboelectric nanogenerator; as follows. Figure 3As shown in (a), the 32 teeth are divided into 4 similar electrodes, simplifying the double-layer staggered chain tooth triboelectric nanogenerator into a staggered electrode triboelectric nanogenerator. The independent layer is set to move from left to right and then from right to left, and one round trip is one cycle of the independent layer's movement. Figure 3 (b) shows a physical diagram of the electrodes and independent layers, such as Figure 3 (c) The image of an independent layer moving for one cycle, the change in current direction corresponds to Figure 3 In case (a), the extreme point corresponds to the point where the independent layer and the electrode overlap. Using an oscilloscope probe connected to the electrodes of the staggered electrode triboelectric nanogenerator, where electrodes ① and ③ are connected together, and electrodes ② and ④ are connected together, the independent layer slides back and forth on electrodes ①, ②, ③, and ④. Other conditions remain unchanged. The time it takes for the independent layer to slide back and forth on the electrodes is changed, with the period of the independent layer's movement set to 0.3s, 0.4s, and 0.5s respectively. The voltage changes are observed. Figure 3 (d) It can be seen that the output voltage of the staggered electrode triboelectric nanogenerator decreases as the independent layer motion period increases, with the period being within 0.3 to 0.5 s. This indicates that the shorter the independent layer motion period, the greater the output voltage.

[0048] like Figure 4 As shown in (a), the double-layer staggered chain tooth triboelectric nanogenerator can be further simplified into a double-layer staggered electrode triboelectric nanogenerator, with one electrode having a surface area of ​​840 mm². 2 (32mm×26.25mm), by changing the motion cycle of the independent layer, it can be seen that the shorter the motion cycle of the independent layer, the higher the output voltage is generated. Figure 4 (b) and Figure 3 (d) Under the same motion period, the output voltage generated by the double-layer staggered electrode triboelectric nanogenerator is slightly smaller. This is because, under the same electrode surface area, the number of connecting wires in the double-layer type is twice that of the staggered electrode type. When the wires on the same electrode group are connected together, the resistance generated by the double-layer staggered electrode triboelectric nanogenerator is slightly greater than that of the staggered electrode triboelectric nanogenerator. The period of movement of the independent layer on the electrode is 0.3s, the output voltage is about 35.4V, and the output current is about 0.67uA.

[0049] Based on the above experiments, it can be concluded that the double-layered staggered electrode triboelectric nanogenerator can work normally, such as... Figure 4 (c) The interleaved electrodes were replaced with an interleaved chain-tooth triboelectric nanogenerator, and its output voltage was measured. First, the chain teeth were divided into metal chain teeth and non-metal chain teeth. An experiment was designed to compare a 2mm thick copper sheet as a chain tooth with a copper film attached to acrylic as a chain tooth; [e.g.] Figure 4As shown in (d), the independent layer moves back and forth on the electrode in a cycle of 0.5s. The output voltage with metal chain teeth as electrodes is approximately 25.8V, and the output voltage with non-metallic chain teeth as electrodes is approximately 17V. Since the bottom of every four non-metallic teeth is connected together, the contact area between the independent layer and the electrode is (1100mm²). 2 The contact area of ​​the four teeth connected together is smaller than that of the staggered electrode triboelectric nanogenerator (32mm×52.5mm). Under the same cycle, the output voltage of the triboelectric nanogenerator is smaller than that of the staggered electrode triboelectric nanogenerator. When using copper sheets as chain teeth, it can be found that under the same cycle, its effective output voltage value is smaller than that of the case where copper film is attached to acrylic. Therefore, copper film is selected as the electrode.

[0050] like Figure 5 As shown in (a), the teeth of the double-layered staggered chain tooth triboelectric nanogenerator are configured as two pairs, three pairs, and four pairs of staggered chain teeth as one electrode; as Figure 6 As shown in (a), since the extent of the independent layers initially covers ① all and a small portion ②, the output voltage of the bilayer staggered electrode triboelectric nanogenerator is smaller than that of the bilayer staggered chain tooth triboelectric nanogenerator at the same time; Figure 5 As shown in (b), under the same conditions, the measured output voltage increases sequentially; Figure 5 (c)(d) Compare the staggered electrode triboelectric nanogenerator, the double-layer staggered electrode triboelectric nanogenerator, and the double-layer staggered chain tooth triboelectric nanogenerator. Under the same conditions, compare the output voltage and output current: double-layer staggered chain tooth triboelectric nanogenerator < double-layer staggered electrode triboelectric nanogenerator < staggered electrode triboelectric nanogenerator. Under the same conditions, the output performance of the staggered electrode triboelectric nanogenerator and the double-layer staggered chain tooth triboelectric nanogenerator is not significantly different.

[0051] Based on the above experiment, a copper film was selected as the electrode material, and the electrode was subjected to the following process: Figure 6 (a) Arranged in a double-layered chain tooth shape, consisting of 8 electrodes. The surface area of ​​the copper film attached to each chain tooth is A (105 mm²). 2 Each electrode has a surface area of ​​840 mm². 2 Based on all the above real analogies, the output voltage decreases as the period increases. Since the friction layer initially covers ① all and a small part ②, compared with the double-layer interleaved electrode triboelectric nanogenerator, the output voltage of the double-layer interleaved electrode triboelectric nanogenerator is smaller under the same period of friction layer movement. Under ambient temperature, ambient humidity, and standard atmospheric pressure, an oscilloscope is connected to the double-layer interleaved chain tooth triboelectric nanogenerator to measure the output voltage. Then, a 1MΩ resistor is connected in series in the circuit, and the voltage across the resistor is measured. The current generated in the circuit is calculated using Ohm's law. Figure 6(b) The output voltage and output current are obtained under several sliding cycles by sliding the independent layer. The output voltage increases slightly with the increase of the electrode spacing g (4mm~6mm). Since the amount of transferred charge (Q) is the same within one sliding range, the short-circuit charge density j SC With transfer charge density σ sc have to:

[0052]

[0053] Short-circuit charge density j SC It depends on the duration of a single slide. Increasing the distance *g* between adjacent electrodes leads to a longer movement time for the independent layers, which is detrimental to *j*. SC The increase in the electrode spacing is beneficial to increasing j. SC Reducing the electrode spacing g is beneficial for designing high-output devices; therefore, an electrode spacing of 4mm is optimal. The tooth spacing on each electrode of the double-layered interlaced chain-tooth triboelectric nanogenerator is i (4mm~6mm). Under the condition that the external environment, contact area, force magnitude, and electrode spacing remain constant, the triboelectric nanogenerator is connected to an oscilloscope to obtain the voltage in the circuit. Then, a resistor is connected in the circuit to calculate the current inside the circuit, and the experimental data is analyzed. Figure 6 As shown in (c), at the same speed, the output voltage increases slightly with the increase of the distance between the chain teeth on each electrode. Based on the compactness of the design and the distance between the electrodes, the optimal value of 4mm for the distance between different chain teeth on the same electrode can be obtained; Figure 6 As shown in (d), each tooth in the double-layered staggered chain tooth triboelectric nanogenerator can be considered as a zipper tooth commonly found in everyday life. Therefore, the double-layered staggered chain tooth triboelectric nanogenerator can be seen as a combination of a zipper and a triboelectric nanogenerator. The effect of a sliding zipper is simulated on the double-layered staggered chain tooth triboelectric nanogenerator, and the output voltage under different cycles is measured. Figure 6 As shown in (e), an interlaced chain tooth triboelectric nanogenerator and small LED beads are connected in series to light up about 15 small LED beads. The double-layer interlaced chain tooth triboelectric nanogenerator is used to light up the LED lights.

[0054] in conclusion:

[0055] With the contact area between the independent layer and the electrode, the magnitude of the force, and environmental factors remaining constant, the staggered electrode triboelectric nanogenerator exhibits the best output performance, while the output voltage of the double-layer staggered chain tooth triboelectric nanogenerator is slightly lower. As the speed of the friction layer in the staggered electrode triboelectric nanogenerator, the double-layer electrode triboelectric nanogenerator, and the double-layer staggered chain tooth triboelectric nanogenerator gradually increases, the output voltage gradually decreases. The chain teeth are designed with metal teeth and non-metal teeth coated with copper film. Under the same conditions, the output voltage of the metal chain teeth as electrodes is not as good as that of the non-metal chain teeth coated with copper film. For staggered chain teeth, non-metal chain teeth coated with metal film should be selected, using two pairs (4), three pairs (6), and four pairs (8) of chain teeth as one electrode. Under the same motion cycle, the output voltage of the double-layer staggered chain tooth triboelectric nanogenerator increases with the increase of chain teeth. Therefore, eight chain teeth were selected as the electrodes of the triboelectric nanogenerator. Under the condition that the contact area between the independent layer and the electrode, the magnitude of the force, the sliding speed and environmental factors remain unchanged, the spacing between the chain teeth on the same electrode and the distance between adjacent electrodes change (4mm~6mm), which affects the output of the double-layer staggered chain tooth triboelectric nanogenerator. The experiment found that the optimal electrode spacing and the optimal chain tooth distance are 4mm. Referring to the previous content, the optimal chain tooth structure is obtained. The zipper structure is in the form of chain teeth, which makes it possible to combine the triboelectric nanogenerator with the zipper, which will play a progressive role in people's lives in the future.

[0056] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A double-layered interlaced chain tooth triboelectric nanogenerator, composed of multiple units and a frame, characterized in that: Each of the multiple units consists of several acrylic sheet teeth, with copper film plated on the teeth to serve as electrodes for the triboelectric nanogenerator. The frame is made of acrylic material, and the surface of the frame is covered with sponge. A polyimide film is then attached to the sponge to serve as an independent layer. The device on one side of the double-layered staggered chain tooth triboelectric nanogenerator consists of two parts: an independent layer and staggered chain teeth. The independent layer is divided into upper and lower parts, each with a 1mm thick sponge layer on its surface. A polyimide film is attached to the surface of the sponge as the independent layer material. The chain tooth shape is cut from an acrylic sheet, and a copper film is attached to one surface of the acrylic sheet with the chain tooth shape to lead out wires. Initially, four chain teeth on one side are covered by the independent layer, so these four teeth covered by the independent layer are used as one electrode. The purpose of attaching sponge to the surface of the frame is to increase the tight contact between the polyimide and the electrode, making the independent layer and the electrode in close contact.

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