Triboelectric nanogenerators with instantaneous discharge and their applications

Abstract

This application belongs to the technical field of triboelectric power generation and wireless sensing, and discloses a triboelectric nanogenerator with instantaneous discharge and its application. The instantaneous discharge triboelectric nanogenerator includes: a rotor, a stator, a first contact electrode, a second contact electrode, and a third contact electrode. Both the rotor and stator are provided with a predetermined, uniformly separated fan-shaped triboelectric layer. The fan-shaped angle of the interval region between adjacent triboelectric layers on the rotor and stator is the same as the fan-shaped angle of the triboelectric layer. An induction electrode is provided on the non-friction contact side of the triboelectric layer. The first contact electrode is electrically connected to the induction electrode on the rotor and is located at the endpoint of the outer arc-shaped boundary of the triboelectric layer on the rotor. The second contact electrode is electrically connected to the induction electrode on the stator, but the third contact electrode is not electrically connected to the induction electrode on the stator and is located at both ends of the outer arc-shaped boundary of the interval region between adjacent triboelectric layers on the stator. This application can improve instantaneous current output.

Description

Technical Field

[0001] This application relates to the technical fields of triboelectric power generation and wireless sensing, and in particular to a triboelectric nanogenerator with instantaneous discharge and its applications. Background Technology

[0002] With the rapid development of the Internet of Things (IoT), billions of sensor nodes are connected in IoT networks. However, powering this massive number of sensors remains a challenging problem. Harvesting environmental energy, such as solar, thermal, and mechanical energy, to power IoT sensors is an effective strategy. As a promising energy harvesting technology, triboelectric nanogenerators (TENGs) can power small electronic devices through the coupling effect of triboelectricity and electrostatic induction, offering advantages such as small size, high output voltage, and low manufacturing cost.

[0003] Besides functioning as energy harvesters, TENGs are essentially self-powered sensors. Without requiring an external power source, they can reveal the contours of mechanical motion through their mapping relationship with the electrical output of the TENGs. Due to their ultra-low internal capacitance, TENGs have a high open-circuit (OC) voltage, giving self-powered sensors a high signal-to-noise ratio (SNR). As a self-powered sensor, TENGs have been successfully applied in self-powered wind speed sensing, pressure sensing, and gas sensing. In conventional TENG-enabled self-powered sensing systems, signal transmission from the sensing unit to the detection station is achieved via a cable connection. However, in some severe environments, such as marine environments, cable connections are not permitted, thus requiring highly efficient wireless sensing units driven by TENGs. Furthermore, the charge signal generated by friction needs to be amplified by a preamplifier, consuming external power, and the signal amplification process is susceptible to electromagnetic interference (EMI).

[0004] Existing approaches, based on triboelectric nanogenerators (TENGs), propose the concept of tribophotons, where the electro-optic effect is achieved by the charge provided by the TENGs. Photons replace electrons, acting as information carriers. Driven by TENGs, developed optical actuators, such as liquid lenses and liquid crystal reflectors, can modulate optical properties including focal length and scattering intensity, and can remotely detect changes in light intensity, thus achieving electromechanical-optical signal conversion without an external power source. Since optical signals can be transmitted in free space without cable connections, triboelectric-photonic devices enable wireless sensing.

[0005] Even though battery-free sensing nodes are achieved through tribological-photonics technology, beam illumination still consumes external energy. Therefore, there is still a demand for fully self-powered sensing that uses photons as the information carrier. However, lasers, as a key component of optical communication systems, require high current but low voltage injection. In traditional TENGs, charge is constantly transferred during the friction between the two triboelectric layers, resulting in a low instantaneous output current. The high injection current (i.e., more than 10mA) and low voltage (i.e., less than 3V) required by lasers are mismatched with the output of TENGs, which have low current (i.e., less than 100uA) and ultra-high voltage (i.e., 1000V). Summary of the Invention

[0006] This application provides a triboelectric nanogenerator with instantaneous discharge and its application, which can improve the output instantaneous current and make it applicable to optical sensing systems to drive lasers.

[0007] In a first aspect, embodiments of this application provide a triboelectric nanogenerator with instantaneous discharge, the triboelectric nanogenerator comprising:

[0008] Rotor, stator, first contact electrode, second contact electrode, and third contact electrode;

[0009] Both the rotor and stator are provided with a preset number of uniformly separated sector-shaped triboelectric layers. The sector angle of the interval region between adjacent triboelectric layers on the rotor and stator is the same as the sector angle of the triboelectric layer. An induction electrode is provided on the non-friction contact side of the triboelectric layer. The product of the number of triboelectric layers and the sector angle of the triboelectric layer is a fixed angle value.

[0010] The first contact electrode is electrically connected to the induction electrode on the rotor and is located at the outer arc-shaped boundary endpoint of the triboelectric layer on the rotor.

[0011] The second contact electrode is electrically connected to the induction electrode on the stator, and the third contact electrode is not electrically connected to the induction electrode on the stator. They are respectively disposed at both ends of the outer arc-shaped boundary of the interval region between adjacent triboelectric layers on the stator.

[0012] Furthermore, during the rotation of the rotor of the instantaneous discharge triboelectric nanogenerator, the first contact electrode collides with the second and third contact electrodes respectively.

[0013] When the first contact electrode collides with the second contact electrode, the triboelectric layers on the stator and rotor completely overlap, causing the driven electrostatic induction to cancel out, and the charge carried by the induction electrodes on the stator and rotor disappears.

[0014] When the first contact electrode does not collide with the second and third contact electrodes, the amount of charge carried by the corresponding induction electrodes on the stator and rotor remains unchanged.

[0015] When the first contact electrode collides with the third contact electrode, the triboelectric layers on the stator and rotor completely separate, and the accumulated charge carried by the induction electrodes on the stator and rotor is transferred, generating an instantaneous current with a current value not less than the driving current threshold.

[0016] Furthermore, the instantaneous current is calculated based on the charge change of the induction electrodes on the stator and rotor before and after the collision of the first contact electrode and the third contact electrode, and the collision time of the electrical connection between the first contact electrode and the third contact electrode. The formula for calculating the instantaneous current is as follows:

[0017]

[0018]

[0019] Where I1 is the instantaneous current, Q1 is the change in charge of the induction electrodes on the stator and rotor before and after the collision of the first contact electrode and the third contact electrode, r is the radius of the induction electrode on the triboelectric layer, σ is the triboelectric charge density, S is the friction area, and τ is the collision time of the electrical connection between the first contact electrode and the third contact electrode.

[0020] Furthermore, the thickness of the triboelectric layer on the rotor is nonlinearly related to the output of the instantaneous current, the gap distance between the rotor and the stator is negatively related to the output of the instantaneous current, and the rotor speed is unrelated to the output of the instantaneous current.

[0021] Furthermore, the first contact electrode is made of alloy tape, while the second and third contact electrodes are made of alloy sponge.

[0022] Furthermore, the triboelectric layer on the rotor is configured in a curved shape to contact the triboelectric layer on the stator, and the contact between the triboelectric layer on the rotor and the triboelectric layer on the stator is supported by the bending force of the rotor.

[0023] Furthermore, the triboelectric layer on the stator is made of nylon, the triboelectric layer on the rotor is made of FEP, and the induction electrodes on the stator and rotor are made of copper.

[0024] Secondly, embodiments of this application provide an application of a triboelectric nanogenerator with instantaneous discharge, wherein the application is the application of the triboelectric nanogenerator with instantaneous discharge as described above in a self-powered optical sensing system, wherein the self-powered optical sensing system includes:

[0025] The sensing module is used to drive the laser to emit periodic light pulses by using the instantaneous current generated by the triboelectric nanogenerator of instantaneous discharge. The emission frequency of the light pulses is the same as the generation frequency of the instantaneous current and is proportional to the speed of the environmental motion.

[0026] The receiving module is used to remotely receive the light pulse signal emitted by the sensing module, detect the frequency and amplitude of the light pulse signal, determine environmental motion information based on the frequency of the light pulse signal, and determine the medium pollution information in the environment based on the amplitude of the light pulse signal.

[0027] Furthermore, the laser also includes a laser diode with a peak emission wavelength of a preset wavelength, an optical lens for collimation, and an aluminum alloy housing, with the second and third contact electrodes electrically connected to the laser diode.

[0028] Furthermore, the receiving module also includes:

[0029] Silicon photodetectors are used to remotely receive light pulse signals emitted by sensing modules and convert the frequency and amplitude of the light pulse signals into corresponding electrical signals.

[0030] An oscilloscope, connected to a high-speed silicon photodetector cable, is used to capture the electrical signals converted by the high-speed silicon photodetector and transmit the electrical signal data to a computer.

[0031] Computers are used to process and display electrical signal data to determine environmental motion information and environmental pollution information.

[0032] In summary, compared with the prior art, the beneficial effects of the technical solution provided in this application include at least the following:

[0033] This application provides a triboelectric nanogenerator with instantaneous discharge and its application. The triboelectric nanogenerator with instantaneous discharge in this application has structural improvements compared to existing triboelectric nanogenerators. By setting contact electrodes to achieve instantaneous electrical switching, when the triboelectric nanogenerator with instantaneous discharge is driven, the instantaneous electrical switching of the contact electrodes on it during rotation can release all the accumulated charge of the triboelectric layer in a very short time, generating periodic ultra-high instantaneous current pulses. The instantaneous current output of this is greatly improved compared to existing triboelectric nanogenerators, and the periodic ultra-high instantaneous current pulses can be applied to optical sensing systems to drive lasers. Attached Figure Description

[0034] Figure 1 The figures show a top view (a) and a front view (b) of the rotor and a top view (c) and a front view (d) of the stator in a triboelectric nanogenerator for instantaneous discharge according to an embodiment of this application; wherein the reference numerals in the figures have the following meanings: 1-rotating substrate, 2-triboelectric layer on the rotor, 3-induction electrode on the rotor, 4-first contact electrode, 5-stator substrate, 6-triboelectric layer on the stator, 7-second contact electrode, 8-third contact electrode.

[0035] Figure 2This is a schematic diagram of a working cycle of a triboelectric nanogenerator with instantaneous discharge provided in one embodiment of this application.

[0036] Figure 3 A comparison of the electrical performance of the output of a triboelectric nanogenerator for instantaneous discharge and an existing triboelectric nanogenerator.

[0037] Figure 4 The figures show a top view (a), a front view (b), and an isometric side view (c) of a sensing module in a self-powered optical sensing system for the application of a transient discharge triboelectric nanogenerator according to an embodiment of this application. The reference numerals in the figures have the following meanings: S1 - transient discharge triboelectric nanogenerator, S2 - wire, S3 - laser.

[0038] Figure 5 A schematic diagram showing the optical characteristics and verification results of a triboelectric nanogenerator driving a laser with instantaneous discharge, provided in one embodiment of this application.

[0039] Figure 6 This is a schematic diagram of the monitoring and monitoring results of the sensing module in a self-powered optical sensing system for the application of a triboelectric nanogenerator with instantaneous discharge, provided in one embodiment of this application.

[0040] Figure 7 This diagram illustrates a comparison of theoretical and practical values ​​of the sensing module in a self-powered optical sensing system for monitoring environmental pollution and motion, based on an embodiment of this application of a triboelectric nanogenerator with instantaneous discharge. Detailed Implementation

[0041] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0042] Please see Figure 1 This application provides a triboelectric nanogenerator with instantaneous discharge, which specifically includes:

[0043] Rotor, stator, first contact electrode, second contact electrode, and third contact electrode;

[0044] Both the rotor and stator are provided with a preset number of uniformly separated sector-shaped triboelectric layers. The sector angle of the interval region between adjacent triboelectric layers on the rotor and stator is the same as the sector angle of the triboelectric layer. An induction electrode is provided on the non-friction contact side of the triboelectric layer. The product of the number of triboelectric layers and the sector angle of the triboelectric layer is a fixed angle value.

[0045] The first contact electrode is electrically connected to the induction electrode on the rotor and is located at the outer arc-shaped boundary endpoint of the triboelectric layer on the rotor.

[0046] The second contact electrode is electrically connected to the induction electrode on the stator, and the third contact electrode is not electrically connected to the induction electrode on the stator. They are respectively disposed at both ends of the outer arc-shaped boundary of the interval region between adjacent triboelectric layers on the stator.

[0047] In this embodiment, the instantaneous discharge triboelectric nanogenerator, based on the existing triboelectric nanogenerator, incorporates three contact electrodes to achieve instantaneous electrical switching. Among the three newly added contact electrodes, refer to... Figure 1 The first contact electrode (4) is electrically connected to the induction electrode (3) on the rotor, the second contact electrode (7) is electrically connected to the induction electrode on the stator, and the third contact electrode (8) is not electrically connected to the induction electrode on the stator. The triboelectric layer (2) on the rotor is a negative triboelectric layer and is correspondingly disposed on the rotating substrate (1) for rotation. The triboelectric layer (6) on the stator is a positive triboelectric layer and is correspondingly disposed on the stator substrate (5). Both the rotor and stator are provided with a preset number of uniformly separated sector-shaped triboelectric layers. The number of triboelectric layers multiplied by the sector angle of the triboelectric layer is a fixed angle value, which is 180°. The triboelectric layers are uniformly distributed and occupy half the area of ​​the entire substrate. In this embodiment, a sector-shaped triboelectric layer with a sector angle of 45° is used, therefore four triboelectric layers are set. If a sector-shaped triboelectric layer with a sector angle of 30° is used, six triboelectric layers can be set, and so on. The sector angle of the interval region between adjacent triboelectric layers on the rotor and stator is the same as the sector angle of the triboelectric layer. The second contact electrode is electrically connected to the induction electrode on the stator, while the third contact electrode is not electrically connected to the induction electrode on the stator. They are respectively set at both ends of the outer arc-shaped boundary of the interval region between adjacent triboelectric layers on the stator, while the first contact electrode is set at the end of the outer arc-shaped boundary of the triboelectric layer on the rotor. With the above settings, corresponding to one rotation cycle, when the first contact electrode collides with the second contact electrode, the triboelectric layers on the stator and rotor completely overlap, entering a short-circuit state of charge recombination. During the process from the second contact electrode to the third contact electrode, the open-circuit state means that the charge on the two induction electrodes cannot be transferred regardless of whether the rotation is active or not. When the first contact electrode collides with the third contact electrode, the triboelectric layers on the stator and rotor completely separate, entering a short-circuit state of charge transfer. The charge accumulated in the period before the collision of the first and second contact electrodes is released during the switching time, which is the collision time of the first and third contact electrodes. By minimizing the charge transfer duration, ultra-high instantaneous current output can be generated.

[0048] Furthermore, in one embodiment, during the rotation of the rotor of the instantaneous discharge triboelectric nanogenerator, the first contact electrode collides with the second contact electrode and the third contact electrode respectively.

[0049] When the first contact electrode collides with the second contact electrode, the triboelectric layers on the stator and rotor completely overlap, causing the driven electrostatic induction to cancel out, and the charge carried by the induction electrodes on the stator and rotor disappears.

[0050] When the first contact electrode does not collide with the second and third contact electrodes, the amount of charge carried by the corresponding induction electrodes on the stator and rotor remains unchanged.

[0051] When the first contact electrode collides with the third contact electrode, the triboelectric layers on the stator and rotor completely separate, and the accumulated charge carried by the induction electrodes on the stator and rotor is transferred, generating an instantaneous current with a current value not less than the driving current threshold.

[0052] In this embodiment, the instantaneous electrical switch of the instantaneous discharge triboelectric nanogenerator is implemented by three contact electrodes to select the connection state of the induction electrodes on the rotor and stator. When the first contact electrode is connected to the second contact electrode, the triboelectric layers on the stator and rotor completely overlap, and the charge carried by the corresponding induction electrodes on the stator and rotor disappears. When the first contact electrode is not connected to the second or third contact electrode, the amount of charge carried by the corresponding induction electrodes on the stator and rotor remains unchanged. When the first contact electrode is connected to the third contact electrode, the triboelectric layers on the stator and rotor separate, and the charge carried by the corresponding induction electrodes on the stator and rotor transfers, generating an ultra-high instantaneous current. After the triboelectric charge accumulation between the stator and rotor triboelectric layers reaches saturation (approximately after 2-3 rotations of the friction surface), the amount of charge on the induction electrodes of the stator and rotor remains unchanged, allowing for a continuous supply of ultra-high instantaneous current.

[0053] The instantaneous discharge triboelectric nanogenerator operates cyclically, referring to... Figure 2Taking a single working cycle as an example, a working cycle consists of four stages. When the rotator is in the first stage (Step 1), since the induction electrodes of the rotator and stator are in an open-circuit state, the induction electrodes under the two triboelectric layers are not electrically connected, and charge cannot be transferred between the induction electrodes. The charge state on the induction electrodes remains unchanged. Then, when the electrically connected first and second contact electrodes collide, the induction electrodes of the stator and rotor are in a short-circuit state of charge recombination. In this second stage (Step 2), the two triboelectric layers are in complete contact. Whether it is a positive or negative induction electrode, the generation of electrostatic force is driven by electrons inside the free induction electrode by positive and negative triboelectric forces, and the charge values ​​of the two are the same but their directions are opposite. Therefore, the result is zero electrostatic force, which means that there is no electrostatic induction to charge the induction electrodes. In the subsequent third stage (Step 3), the first and second contact electrodes are electrically disconnected before the collision of the first and third contact electrodes, and the two sensing electrodes are again in an open-circuit state, maintaining their empty charge state. Finally, the first and third contact electrodes collide, reaching the fourth stage (Step 4), where the rotor and stator are about to separate, and the two sensing electrodes are short-circuited for charge transfer, providing an ultra-high instantaneous current from the instantaneous discharge triboelectric nanogenerator to the laser. After the collision, the first and third contact electrodes separate, and Step 1 restarts after one cycle. Assuming that the total electrical energy harvested from the mechanical motion is the same, minimizing the charge transfer duration means enhancing the intensity of the current through the external circuit. Unlike conventional triboelectric nanogenerators with charge transfer times greater than 0.1 s, the collision time of the instantaneous triboelectric nanogenerator in this embodiment is less than 0.1 ms, providing at least a 1000-fold increase in instantaneous current, such a high instantaneous current is necessary to drive the laser for illumination.

[0054] Furthermore, in one embodiment, the instantaneous current is calculated and determined based on the charge change of the induction electrodes on the stator and rotor before and after the collision of the first contact electrode and the third contact electrode, and the collision time of the electrical connection between the first contact electrode and the third contact electrode. The formula for calculating the instantaneous current is:

[0055]

[0056]

[0057] Where I1 is the instantaneous current, Q1 is the change in charge of the induction electrodes on the stator and rotor before and after the collision of the first contact electrode and the third contact electrode, r is the radius of the induction electrode on the triboelectric layer, σ is the triboelectric charge density, S is the friction area, and τ is the collision time of the electrical connection between the first contact electrode and the third contact electrode.

[0058] In this embodiment, for the rotor and stator, the change in charge on the induction electrode before and after the collision between the first contact electrode on the rotor and the third contact electrode on the stator is equal to the charge of the triboelectric layer, which is determined by the triboelectric charge density σ (nC / cm²) and the friction area S (cm²). 2 The product definition of ). Therefore, the change in charge on the induced electrodes before and after the collision between the first contact electrode on the rotor and the third contact electrode on the stator (i.e., the amount of charge transferred Q1) can be expressed as:

[0059]

[0060] In the formula, r is the radius of the arc-shaped sensing electrode, and the area of ​​all sensing electrodes is equal to the area of ​​a semicircle.

[0061] The instantaneous current I1 generated by the instantaneous discharge triboelectric nanogenerator when the first contact electrode collides with the third contact electrode can be calculated by dividing the transferred charge Q1 by the collision time of the electrical connection, and can be expressed as:

[0062]

[0063] In the formula, τ is the collision time when the first contact electrode and the third contact electrode are electrically connected.

[0064] In existing triboelectric nanogenerators, the charge on the inductive electrode is continuously transferred to the external circuit under the drive of the separation of the two triboelectric layers. Compared with triboelectric nanogenerators that generate instantaneous power, the instantaneous current of regular triboelectric nanogenerators is much lower, making it extremely difficult to drive lasers. Within a certain period t, the absolute amount of transferred charge of a regular RS-TENG, independent of the current direction Q2, can be expressed as:

[0065]

[0066] Where ΔS is the separation area, and ω is the angular velocity of the canonical RS-TENG. The generated current can be expressed as:

[0067]

[0068] Where f(Hz) is the rotational frequency of the regular triboelectric nanogenerator. In this embodiment, the collision time τ is extremely short, far below 100μs, and the ambient rotational speed typically does not exceed 5Hz. Therefore, theoretically, it can be deduced from the above calculations that the triboelectric nanogenerator of this embodiment can increase the instantaneous current by at least 1000 times, making it an excellent pulsed power source for driving lasers for optical sensing purposes.

[0069] Reference Figure 3Images (a)-(c) show the measured electrical performance of the instantaneous discharge triboelectric nanogenerator (RDID-TENG) and the existing triboelectric nanogenerator (RS-TENG). The generator's structural parameters are: rotational speed 120 r / min, triboelectric layer thickness on the rotor set to 150 μm, rotor-stator gap distance set to 0.7 cm, and short-circuit current (I0). SC ), open circuit voltage (V) OC ), transferred charge (Q). From Figure 3 (a) It can be observed that the current generated by the instantaneous discharge triboelectric nanogenerator exhibits a well-defined periodicity. The charge transfer time driven by the contact electrode collisions is so rapid that the current spectrum exhibits a needle-like shape, with measurements showing a timeframe within 500 ms. From Figure 3 (b) It can be observed that, for one rotation cycle, the transferred charge of the instantaneously discharging triboelectric nanogenerator in this embodiment is 173 nC, which is less than half that of a conventional RFS-TENG with the same friction area (371 nC). However, theoretically, the total transferred charge of both should be the same during one discharge process, which is equivalent to the same triboelectric charge. This indicates that the charge loss occurs during the breakdown discharge of the electric field formed by the extremely close but non-contact contact electrodes E1 and E3 before the collision in the instantaneously discharging triboelectric nanogenerator. Figure 3 (c) It can be observed that, thanks to the ultra-low internal capacitance of the triboelectric nanogenerator, the open-circuit voltage (VTENG) of the RDID-TENG is [missing information]. OC Up to 1250V.

[0070] Furthermore, in one embodiment, the thickness of the triboelectric layer on the rotor is non-linearly related to the output of the instantaneous current, the gap distance between the rotor and the stator is negatively related to the output of the instantaneous current, and the rotor speed is unrelated to the output of the instantaneous current.

[0071] In this embodiment, to determine whether the pressure between different triboelectric layers on the rotor and stator affects the electrical performance (including instantaneous current, open-circuit voltage, and transferred charge) of the instantaneously discharging triboelectric nanogenerator, reference is made. Figure 3 In (d) and (e), the pressure between the triboelectric layers was adjusted by experimentally controlling the distance between the stator and rotor, and the output performance of the instantaneous discharge triboelectric nanogenerator under different distances, including short-circuit current and open-circuit voltage, was measured. When the distance between the stator and rotor increased from 0.7 cm to 3.0 cm, the short-circuit current (If) of the instantaneous discharge triboelectric nanogenerator decreased due to the reduction in friction area. SC ), open circuit voltage (V) OCBoth decreased. The amount of transferred charge (Q) also exhibited characteristics with different gap distances, and its trend was similar to that of the short-circuit current results. Therefore, in this embodiment, for the instantaneous discharge triboelectric nanogenerator of this embodiment, the thickness of the triboelectric layer on the rotor is negatively correlated with the output of the instantaneous current. The thickness of the triboelectric layer on the rotor and the gap distance between the rotor and the stator can be adjusted to meet the requirements of the electrical output performance of the instantaneous discharge triboelectric nanogenerator.

[0072] Meanwhile, to determine whether the thickness of the triboelectric layer on the rotor affects the electrical performance (including instantaneous current, open-circuit voltage, and transferred charge) of the triboelectric nanogenerator during instantaneous discharge, reference was made. Figure 3 In (f) and (g), the effects of different thicknesses (10 μm to 500 μm) on the electrical performance of the transient discharge triboelectric nanogenerator were explored experimentally. The electrical performance of the transient discharge triboelectric nanogenerator increased rapidly with increasing thickness. At a thickness of 150 μm, the short-circuit current (I) increased significantly. SC ), open circuit voltage (V) OC Both the transferred charge (Q) and the peak value are reached. With further increases in thickness, the bending force of the sector-shaped triboelectric layer on the rotor increases, leading to higher pressure between the sector-shaped triboelectric layer on the rotor and the sector-shaped triboelectric layer on the stator, increasing the contact area and raising the triboelectric charge. However, when the bending force exceeds a certain level, due to pressure overload, a certain area of ​​the sector-shaped triboelectric layer on the rotor diffuses out from the sector-shaped triboelectric layer on the stator, reducing the contact friction area and suppressing charge output. Therefore, after a thickness of 150 μm, the electrical output performance of the instantaneous discharge triboelectric nanogenerator decreases as the thickness of the sector-shaped triboelectric layer on the rotor continues to increase. Therefore, for the instantaneous discharge triboelectric nanogenerator of this embodiment, the thickness of the triboelectric layer on the rotor is non-linearly related to the instantaneous current output.

[0073] Furthermore, to determine whether rotor speed affects the output performance of the triboelectric nanogenerator with instantaneous discharge, reference was made. Figure 3 The values ​​(h) and (i) in the figure were used to control the rotational speed experimentally, and the output performance of the instantaneous discharge triboelectric nanogenerator was measured at different distances, including short-circuit current and open-circuit voltage. This allowed for the determination of Isc and V, the output performance parameters of the instantaneous discharge triboelectric nanogenerator. OC Since the speed and Q are not significantly affected by the rotor speed, it can be determined that the rotor speed is unrelated to the output of the instantaneous current, and the speed sensing stability is relatively good.

[0074] Furthermore, in one embodiment, the triboelectric layer on the rotor is configured in a curved shape to contact the triboelectric layer on the stator, and the contact between the triboelectric layer on the rotor and the triboelectric layer on the stator is supported by the bending force of the rotor.

[0075] In this embodiment, the triboelectric layer on the rotor is configured in a curved shape to contact the triboelectric layer on the stator. The contact between the triboelectric layer on the rotor and the triboelectric layer on the stator is supported by the bending force of the rotor, which buffers the imbalance caused by rotation and minimizes friction and wear. The rotor has one end fixedly connected to the rotating substrate and the other end free.

[0076] Furthermore, in one embodiment, the first contact electrode is made of alloy tape, and the second and third contact electrodes are made of alloy sponge.

[0077] In this embodiment, in order to minimize energy loss caused by contact electrode collisions during rotation, the second and third contact electrodes are made of alloy sponge to buffer the torque caused by the first contact electrode made of alloy tape.

[0078] Furthermore, in one embodiment, the triboelectric layer on the stator is made of nylon, the triboelectric layer on the rotor is made of FEP, and the induction electrodes on the stator and rotor are made of copper.

[0079] In this embodiment, the triboelectric layer on the stator is made of nylon, the triboelectric layer on the rotor is made of fluorinated ethylene propylene copolymer (FEP), and the induction electrodes on both the stator and rotor are made of copper. During the frictional contact between the triboelectric layers on the stator and rotor, the friction between the two materials causes an electrostatic effect on the induction electrodes, generating and accumulating induced charges.

[0080] This application also provides an application of a triboelectric nanogenerator with instantaneous discharge, wherein the application is the application of the triboelectric nanogenerator with instantaneous discharge as described above in a self-powered optical sensing system.

[0081] Reference Figure 4 The top view (a), front view (b), and isometric side view (c) of the sensing module in a self-powered optical sensing system for the application of a triboelectric nanogenerator with instantaneous discharge provided in one embodiment of this application.

[0082] In this embodiment, the self-powered optical sensing system includes:

[0083] The sensing module is used to drive the laser to emit periodic light pulses by using the instantaneous current generated by the triboelectric nanogenerator of instantaneous discharge. The emission frequency of the light pulses is the same as the generation frequency of the instantaneous current and is proportional to the speed of the environmental motion.

[0084] The receiving module is used to remotely receive the light pulse signal emitted by the sensing module, detect the frequency and amplitude of the light pulse signal, determine environmental motion information based on the frequency of the light pulse signal, and determine the medium pollution information in the environment based on the amplitude of the light pulse signal.

[0085] In this embodiment, the self-powered optical sensing system includes a sensing module laid in the monitoring environment and a remotely set receiving module. The sensing module is used to emit light pulses carrying environmental information, and the receiving module is used to receive the light signals emitted by the sensing module, and detect and process the frequency and intensity information of the light signals to obtain the environmental movement and pollution status in the monitoring environment.

[0086] The sensing module includes a transient discharge triboelectric nanogenerator S1 and a laser S3, which are connected by a wire S2. The transient discharge triboelectric nanogenerator in the sensing module is driven by the rotational mechanical energy of environmental motion, including but not limited to wind, waves, wheels, and generators. When driven by the rotational mechanical energy of environmental motion, the first contact electrode on the rotor collides with the third contact electrode, and the transient electrical switch can release all the accumulated charge on the induction electrode on the triboelectric layer in a very short time, generating a periodic ultra-high transient current pulse I. Taking a required power of 5mW as an example, the transient current of the transient discharge triboelectric nanogenerator can reach up to 19.6mA, which is 1000 times the 0.173mA current achievable by conventional triboelectric nanogenerators. Therefore, the periodic ultra-high transient current pulse is sufficient to drive the laser electrically connected to the transient discharge triboelectric nanogenerator to emit a pulse beam carrying environmental wind speed information. The conversion between mechanical and electrical signals is achieved through a completely self-powered method using the coupling effect of triboelectric charging and electrostatic induction. The receiving module remotely receives laser light. The amplitude of the light beam contains information about the contamination of the medium through which the laser pulse beam passes. Since the laser pulse propagates through free space, it can be remotely received and detected by the receiving module without the need for wires connecting the sensing module and the receiving module.

[0087] By combining a transient discharge triboelectric nanogenerator with a laser, simultaneous information sensing and wireless communication are achieved. This self-powered optical sensing system can effectively monitor environmental movement and pollution in these environments simultaneously using a completely wireless, self-powered approach. It can be applied to long-term ocean observation, disaster prediction on inhabited islands, and widely distributed pollution monitoring scenarios. Furthermore, due to its completely wireless self-powered nature, the sensing module of this self-powered optical sensing system can be deployed in harsh environments where general power supplies are unavailable, such as uninhabited islands and jungles.

[0088] In one embodiment, the laser further includes a laser diode with a peak emission wavelength of a preset wavelength, an optical lens for collimation, and an aluminum alloy housing, wherein the second contact electrode and the third contact electrode are electrically connected to the laser diode.

[0089] In this embodiment, the laser electrically connected to the instantaneous discharge triboelectric nanogenerator further includes a laser diode with a peak emission wavelength of a preset wavelength (e.g., 635 nm), an optical lens for collimation, and an aluminum alloy casing. (Refer to...) Figure 5 (a) is a schematic diagram illustrating the principle of a laser driven by a triboelectric nanogenerator with instantaneous discharge in the sensing module. When the first and third contact electrodes collide, a transient ultra-high current flows through the laser. From an electrical perspective, it can be considered a diode with a pn junction. The semiconductor material in the laser has two energy levels: a high-energy level called the valence band (or hole) and a low-energy level called the conduction band (or electron). Driven by the generated transient ultra-high current, electrons in the high-energy level combine with holes in the low-energy level to form hole-electron pairs and emit photons. This is followed by an excitation and resonance process, where the photons are collimated by a convex lens with a small divergence angle, allowing them to propagate over long distances in free space.

[0090] When the instantaneously discharging triboelectric nanogenerator is integrated with the laser as a sensing module, the second and third contact electrodes are electrically connected to the laser diode in the laser, serving as charge transfer channels from the instantaneously discharging triboelectric nanogenerator to the external circuit.

[0091] Furthermore, in one embodiment, the receiving module further includes:

[0092] Silicon photodetectors are used to remotely receive light pulse signals emitted by sensing modules and convert the frequency and amplitude of the light pulse signals into corresponding electrical signals.

[0093] An oscilloscope, connected to a high-speed silicon photodetector cable, is used to capture the electrical signals converted by the high-speed silicon photodetector and transmit the electrical signal data to a computer.

[0094] Computers are used to process and display electrical signal data to determine environmental motion information and environmental pollution information.

[0095] In this embodiment, the receiving module consists of three components: a high-speed silicon photodetector (PD), an oscilloscope, and a personal computer (PC). The high-speed silicon photodetector possesses extremely high response speed and sensitivity, enabling it to receive light pulse signals emitted by the sensing module remotely and promptly, converting the frequency and amplitude of the light pulse signals into corresponding electrical signals. A single cable connects the output of the silicon photodetector to the oscilloscope, which quickly captures the high-frequency electrical signals and transmits the data to the PC for processing and display. Thanks to the integration of a transient discharge triboelectric nanogenerator and a laser into the sensing module, mechanical-electrical-optical signal conversion becomes possible. Environmental movement speeds, such as wind speed, are proportional to the emission frequency of the laser pulses driven by the transient discharge triboelectric nanogenerator. According to the Lambert-Beer law, the extinction of a medium decays exponentially with increasing contaminant concentration. Therefore, the receiving module can reveal medium contamination information from the intensity attenuation of the remotely received light signal. Thus, by analyzing the frequency and amplitude of the received light signal, environmental movement speed and medium contamination can be revealed in real-time, wirelessly, and self-powered manner.

[0096] To verify the optical performance of the triboelectric nanogenerator-driven laser triggered by an adjustable-speed motor-induced instantaneous discharge, a corresponding characterization platform was constructed, such as... Figure 5 As shown in (c). Due to experimental limitations, a triboelectric nanogenerator (RDID-TENGs) with optimized structural parameters (150 μm thickness of the triboelectric layer on the rotor, and a gap distance of 0.7 cm between the rotor and stator) was used to drive the laser. The initial motor speed was set to 120 r / min. The pulsed light emitted by the laser was received by a photodetector (PD) connected to an oscilloscope, and the voltage drop V of the PD was measured. r It is proportional to the intensity of light radiation. The sensing distance d between the PD and the laser was initially set to 0.5m. Before being triggered by RDID-TENGs, the laser was initially driven by a commercial power supply, in which the current (I) passing through the laser... L () is variable. For example... Figure 5 As shown in (d), to illuminate the laser, the driving current (I) L The current must be above 17 mA, which is beyond the reach of most conventional triboelectric nanogenerators (such as RS-TENGs), except for the improved instantaneous discharge triboelectric nanogenerators (RDID-TENGs) in this embodiment. When the driving current is above 25 mA, the change in light intensity is negligible compared to the sharp increase from 17 mA to 25 mA, due to the laser being in a saturated state.

[0097] The optical characterization results of the RDID-TENGs driven laser are as follows: Figure 5 As shown in (e), the PD voltage drop is close to 12V. This is because the laser is in a saturated state. Figure 5(e) shows light intensity variations during different periods that are much lower than Figure 3 The current change shown in (a) improves the sensing reliability of the developed system. For example... Figure 5 As shown in (b), (g), and (h), the PD(I) is characterized when the sensing distance d is adjusted. L The voltage drop is significant. The periodic profile of the optical signal is unaffected by the increase in sensing distance. However, as the sensing distance lengthens, the signal strength decreases exponentially due to light diffusion and scattering by particles in the air. Due to space limitations within the laboratory, the longest sensing system was limited to 50m. The laser beam spot emitted at distances of 0.5m and 50m was captured, as shown... Figure 5 As shown in (b). Figure 5 (b) shows a comparison of laser spots illuminating the screen at distances of 0.5m and 50m, respectively, with a laser driving current of 25mA. Light diffusion during propagation was identified. Considering... Figure 5 (g) shows the relationship between observed light intensity and sensing distance, and the fact that a 1mV PD voltage drop signal can be well recognized by the equipment. Based on this, the maximum permissible sensing distance is calculated to be as high as 278.6m, which is consistent with near-shore marine observation conditions. Furthermore, the experiment also verified that adjusting the rotation speed of the RDID-TENGs from 30 r / min to 480 r / min yielded the following relationship: [The text abruptly ends here, so the translation stops as well.] Figure 5 As shown in (f). In Figure 5 The excellent linearity of 0.9999 observed in (f) demonstrates the effectiveness of the improved RDID-TENGs driven laser in this embodiment as a fully self-powered wireless rotation sensor.

[0098] To demonstrate the effectiveness of RDID-TENGs in self-powered environmental sensing, two practical applications have been implemented to measure environmental motion and pollution in a fully self-powered and wireless manner. The first demonstration is a wind speed remote sensing optical sensing system, configured as follows: Figure 6 As shown in (a), a wind cup is mechanically connected to the rotator shaft of the modified RDID-TENG to harvest wind energy from the environment. An adjustable-speed wind turbine simulates natural wind to trigger the RDID-TENG. A signal receiving module and... Figure 5 The same as mentioned above. Due to space limitations within the laboratory, the sensing distance is set to a maximum of 50 meters. For example... Figure 6 As shown in (b), the optical signals received by the PD are analyzed when RDID-TENGs are triggered by wind speeds ranging from 3.5 m / s to 12.4 m / s. The higher the wind speed, the denser the corresponding optical signal profile. Figure 6As shown in (c), the relationship between the laser pulse emission frequency and wind speed is fitted with a straight line, exhibiting excellent linearity of 0.9993. This demonstrates that the sensing module integrating the instantaneous discharge triboelectric nanogenerator with the laser possesses good sensing capabilities. According to the fitted curve, the minimum wind speed driving the RDID-TENGs is 1.57 m / s.

[0099] Building upon the first practical application, another practical application involves self-powered and wireless environmental pollution sensing. According to the Lambert-Beer law, for a given optical path length, the intensity of attenuated transmitted light decreases exponentially with increasing concentration of light-absorbing molecules. In practical applications, most pollutants in seawater exhibit light-absorbing properties, and light-absorbing methods have been successfully applied to identify the concentration of a given chemical liquid. In this work, a 623nm pulsed light emitted by a laser driven by RDID-TENGs is used as the incident light, penetrating the contaminated liquid medium. The concentration of the pollutant can be obtained by the intensity of the light after attenuation by the medium in a completely wireless and self-powered manner. In this work, a water tank filled with water was prototyped. Pigments, acting as pollutants, were mixed with water in different mixing ratios, leaving different concentrations of pollutants. The received light signals at different pigment concentrations are shown below. Figure 6 As shown in (e), the driving conditions of the laser and RDID-TENGs remain constant. With increasing pigment concentration, the light intensity decreases due to stronger light attenuation. Figure 6 As shown in (f), the dependence of received light intensity on pigment concentration is subjected to exponential fitting, and the fitting formula is shown here. Using the fitted formula, the pigment concentration can be derived from the remotely detected light intensity. Figure 6 As shown in (e), the light signal frequency represents wind speed information, and the light intensity represents water pollution information. This practical application demonstrates that environmental motion and pollution information can be sensed simultaneously. Experiments comparing the theoretical and sensed values ​​for monitoring pollution and wind speed are shown below. Figure 7 As shown, the theoretical and sensor values ​​for simultaneously monitoring pollution and wind speed are very close. This indicates that when the improved instantaneous discharge triboelectric nanogenerator is used in a self-powered optical sensing system, the accuracy of environmental monitoring is very high and the sensing effect is excellent. This provides a good solution for achieving energy-saving, highly integrated, and low-cost environmental monitoring.

[0100] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0101] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A triboelectric nanogenerator with instantaneous discharge, characterized in that, The instantaneous discharge triboelectric nanogenerator includes: a rotor, a stator, a first contact electrode, a second contact electrode, and a third contact electrode; Both the rotor and stator are provided with a preset number of uniformly separated sector-shaped triboelectric layers. The sector angle of the interval region between adjacent triboelectric layers on the rotor and stator is the same as the sector angle of the triboelectric layer. An induction electrode is provided on the non-friction contact side of the triboelectric layer. The product of the number of triboelectric layers and the sector angle of the triboelectric layer is a fixed angle value. The first contact electrode is electrically connected to the induction electrode on the rotor and is located at the outer arc-shaped boundary endpoint of the triboelectric layer on the rotor. The second contact electrode is electrically connected to the induction electrode on the stator, and the third contact electrode is not electrically connected to the induction electrode on the stator. Both are respectively disposed at both ends of the outer arc-shaped boundary of the spacer region between adjacent triboelectric layers on the stator. During the rotation of the rotor of the instantaneous discharge triboelectric nanogenerator, the first contact electrode collides with the second and third contact electrodes respectively. When the first contact electrode collides with the second contact electrode, the triboelectric layers on the stator and rotor completely overlap, causing the driven electrostatic induction to cancel out, and the charge carried by the induction electrodes on the stator and rotor disappears. When the first contact electrode does not collide with the second and third contact electrodes, the amount of charge carried by the corresponding induction electrodes on the stator and rotor remains unchanged. When the first contact electrode collides with the third contact electrode, the triboelectric layers on the stator and rotor completely separate, and the accumulated charge carried by the induction electrodes on the stator and rotor is transferred, generating an instantaneous current with a current value not less than the driving current threshold.

2. The triboelectric nanogenerator with instantaneous discharge according to claim 1, characterized in that: The instantaneous current is calculated based on the charge change of the induction electrodes on the stator and rotor before and after the collision of the first contact electrode and the third contact electrode, and the collision time of the electrical connection between the first contact electrode and the third contact electrode. The formula for calculating the instantaneous current is as follows: Where I1 is the instantaneous current, Q1 is the change in charge of the induction electrodes on the stator and rotor before and after the collision of the first contact electrode and the third contact electrode, r is the radius of the induction electrode on the triboelectric layer, σ is the triboelectric charge density, S is the friction area, and τ is the collision time of the electrical connection between the first contact electrode and the third contact electrode.

3. The triboelectric nanogenerator with instantaneous discharge according to claim 1, characterized in that: The thickness of the triboelectric layer on the rotor is nonlinearly related to the output of the instantaneous current, the gap distance between the rotor and the stator is negatively related to the output of the instantaneous current, and the rotor speed is unrelated to the output of the instantaneous current.

4. The triboelectric nanogenerator with instantaneous discharge according to claim 1, characterized in that: The first contact electrode is made of alloy tape, and the second and third contact electrodes are made of alloy sponge.

5. The triboelectric nanogenerator with instantaneous discharge according to claim 1, characterized in that: The triboelectric layer on the rotor is configured in a curved shape to contact the triboelectric layer on the stator, and the contact between the triboelectric layer on the rotor and the triboelectric layer on the stator is supported by the bending force of the rotor.

6. The triboelectric nanogenerator with instantaneous discharge according to claim 1, characterized in that: The triboelectric layer on the stator is made of nylon, the triboelectric layer on the rotor is made of FEP, and the induction electrodes on the stator and rotor are made of copper.

7. An application of a triboelectric nanogenerator with instantaneous discharge, characterized in that, The application is the application of the instantaneous discharge triboelectric nanogenerator of any one of claims 1 to 6 in a self-powered optical sensing system, wherein the self-powered optical sensing system comprises: The sensing module is used to drive the laser to emit periodic light pulses by using the instantaneous current generated by the triboelectric nanogenerator of instantaneous discharge. The emission frequency of the light pulses is the same as the generation frequency of the instantaneous current and is proportional to the speed of the environmental motion. The receiving module is used to remotely receive the light pulse signal emitted by the sensing module, detect the frequency and amplitude of the light pulse signal, determine environmental motion information based on the frequency of the light pulse signal, and determine the medium pollution information in the environment based on the amplitude of the light pulse signal.

8. The application according to claim 7, characterized in that: The laser also includes a laser diode with a peak emission wavelength of a preset wavelength, an optical lens for collimation, and an aluminum alloy housing. The second contact electrode and the third contact electrode are electrically connected to the laser diode.

9. The application according to claim 7, characterized in that, The receiving module further includes: Silicon photodetectors are used to remotely receive light pulse signals emitted by sensing modules and convert the frequency and amplitude of the light pulse signals into corresponding electrical signals. An oscilloscope, connected to a high-speed silicon photodetector cable, is used to capture the electrical signals converted by the high-speed silicon photodetector and transmit the electrical signal data to a computer. Computers are used to process and display electrical signal data to determine environmental motion information and environmental pollution information.

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