Self-powered microfluidic mixing device based on triboelectric nanogenerator

Abstract

This application belongs to the field of microfluidics technology, specifically relating to a self-powered microfluidic hybrid device based on a triboelectric nanogenerator. This device possesses self-powering capability, eliminating the need for an external high-voltage power supply and cables, thereby simplifying the structure, reducing size, and improving integration, significantly enhancing its safety, portability, and miniaturization. The device mainly includes a power supply component and a microfluidic chip. The power supply component includes a triboelectric nanogenerator and a power management module. The triboelectric nanogenerator is electrically connected to the power management module, which rectifies and stores the electrical energy output by the triboelectric nanogenerator. The microfluidic chip includes excitation electrodes, which are an asymmetric coplanar electrode array used to generate an electric field within the microfluidic chip to drive the liquid under test to produce a secondary flow. The power management module is electrically connected to the excitation electrodes, providing them with a driving voltage.

Description

Technical Field

[0001] This application relates to the field of microfluidics, and more particularly to a self-powered microfluidic hybrid device based on a triboelectric nanogenerator. Background Technology

[0002] Microfluidics, as an advanced technology that can precisely manipulate tiny volumes of fluid within microchannels, has shown significant advantages in enhancing mass transfer between fluids, providing crucial support for core functions such as sample preparation, detection, reaction, and analysis.

[0003] Microfluidic devices can significantly enhance the mixing efficiency of fluids in a controllable manner, thereby forming reaction products with homogeneous characteristics, which is crucial for the regulation of the chemical properties of the final product. However, achieving rapid and uniform mixing at the microscale still faces significant technical challenges. Within microchannels, fluid flow is primarily characterized by low Reynolds number laminar flow, with molecular diffusion becoming the dominant mixing mechanism, resulting in slow mass transfer rates and thus limiting the operating efficiency and throughput of microfluidic systems. Electro-driven micromixers can improve mixing efficiency to some extent. However, existing electro-driven micromixers rely on high-frequency or high-voltage power supplies for operation. These power supplies are bulky and energy-intensive, severely limiting the practical application of AC-driven microdevices in clinical diagnostics or resource-constrained environments. Furthermore, the high energy consumption caused by high-frequency or high-voltage power supplies can easily lead to electrode passivation, contaminating the sample and affecting the accuracy of test results. Therefore, there is an urgent need for a low-energy-consumption and easily integrated micro-mixing device to meet the needs of portable diagnostics and rapid on-site testing applications. Summary of the Invention

[0004] This application provides a self-powered microfluidic mixing device based on a triboelectric nanogenerator, aiming to solve the problems of existing micromixers, such as reliance on external high-voltage power supplies, large size, easy electrode passivation, and low mixing efficiency at the microscale. This device achieves self-powered operation, eliminating the need for external high-voltage power supplies and cables. It features a simple structure, small size, high integration, and small footprint, significantly improving the device's safety, portability, and miniaturization. Simultaneously, the device has low energy consumption, and the electrodes are less prone to passivation, effectively reducing the risk of sample contamination.

[0005] This application provides a self-powered microfluidic hybrid device based on a triboelectric nanogenerator, comprising a power supply component and a microfluidic chip. The microfluidic chip includes an excitation electrode, which is an asymmetric coplanar electrode array. The excitation electrode is used to excite the liquid to be tested in the microfluidic chip to generate a secondary flow. The power supply component includes a triboelectric nanogenerator and a power management module. The triboelectric nanogenerator and the excitation electrode are respectively electrically connected to the power management module. The power management module is used to store the electrical energy generated by the triboelectric nanogenerator and provide a driving voltage to the excitation electrode.

[0006] In the above embodiments, the triboelectric nanogenerator can efficiently convert low-frequency mechanical energy into high-frequency transient pulse high voltage. After voltage regulation and amplitude modulation by the power management module, it provides controllable high-voltage drive pulses to the microfluidic chip, thereby achieving precise control of fluids without the need for an external power supply. Because it uses a triboelectric nanogenerator for self-powering, the device is free from dependence on traditional high-voltage power supplies and cables, resulting in a more compact overall structure, higher integration, smaller footprint, and good safety and portability. Furthermore, the triboelectric nanogenerator has low power consumption, making it less prone to electrode passivation and effectively reducing the risk of sample contamination. The excitation electrode uses an asymmetric coplanar electrode array, which can excite the test liquid to generate secondary flow, significantly enhancing the disturbance and mixing effect between fluids, thus overcoming the technical challenge of low mixing efficiency caused by molecular diffusion dominance at the microscale.

[0007] In one embodiment, the triboelectric nanogenerator includes a rotor assembly and a friction ring. The rotor assembly is disposed within the friction ring. The rotor assembly includes a planet carrier and a plurality of planetary gears. The plurality of planetary gears are rotatably mounted on the planet carrier. The outer wall of the planetary gears is provided with a friction layer.

[0008] In one embodiment, the friction ring has an interdigitated electrode structure, including an alternating first electrode and a second electrode.

[0009] In one embodiment, a gap exists between the friction layer and the friction ring.

[0010] In one embodiment, the friction layer is made of any one of fluorinated ethylene propylene copolymer, polyimide, and polytetrafluoroethylene.

[0011] In one embodiment, the self-powered microfluidic hybrid device based on a triboelectric nanogenerator further includes a drive assembly, which is connected to the triboelectric nanogenerator. The drive assembly includes a rack, a button, and a gear set, wherein the button is fixedly connected to the rack, the rack meshes with the gear set, and the button is used to drive the planetary carrier to rotate so that the friction layer contacts or separates from the friction ring, thereby generating an electrical signal.

[0012] In one embodiment, the gear set includes a first double gear, a second double gear, a third double gear, and a single-stage gear. The first double gear meshes with the rack, the first double gear and the third double gear mesh with the second double gear respectively, the single-stage gear meshes with the third double gear, and the rotor assembly is fixedly connected to the single-stage gear.

[0013] In one embodiment, the self-powered microfluidic hybrid device based on a triboelectric nanogenerator further includes a housing having a first receiving chamber. The drive assembly is mounted in the first receiving chamber. The first receiving chamber includes a first sidewall and a second sidewall disposed opposite to each other along a first direction. The first sidewall has a mounting hole. The button is inserted into the mounting hole and is slidable along the first direction. A reset member is provided between the button and the second sidewall. The reset member is used to drive the button to reset in a direction away from the second sidewall.

[0014] In one embodiment, the microfluidic chip includes a glass slide and a cover plate stacked together, with the excitation electrode located between the glass slide and the cover plate. The cover plate has a channel for accommodating a sample to be tested.

[0015] In one embodiment, the excitation electrode includes a first electrode group and a second electrode group, respectively disposed on both sides of the channel along its width direction. The first electrode group includes a plurality of first electrode pieces spaced apart along the length direction of the channel, and the second electrode group includes a plurality of second electrode pieces spaced apart along the length direction of the channel. The first and second electrode pieces correspond one-to-one along the width direction of the channel, forming multiple electrode pairs. Along the width direction of the channel, there is a gap between the first and second electrode pieces in each electrode pair; along the length direction of the channel, the gaps corresponding to the multiple electrode pairs are staggered.

[0016] In one embodiment, the channel includes an inlet section and a mixing section connected to each other, the inlet section having multiple branch structures, each of the branch structures communicating with the mixing section.

[0017] In one embodiment, the plurality of branch structures include a first branch and a second branch, wherein the first branch and the second branch are arranged at an angle. Attached Figure Description

[0018] Figure 1 A schematic diagram of a self-powered microfluidic hybrid device based on a triboelectric nanogenerator provided in one embodiment of this application; Figure 2A schematic diagram of the structure of a triboelectric nanogenerator provided in one embodiment of this application; Figure 3 A top view of a triboelectric nanogenerator provided in one embodiment of this application; Figure 4 A schematic diagram of the structure of a driving component provided in one embodiment of this application; Figure 5 A circuit diagram of a power management module provided in one embodiment of this application; Figure 6 This is a schematic diagram of the structure of a microfluidic chip provided in one embodiment of this application; Figure 7 A schematic diagram of the structure of the first electrode sheet, the second electrode sheet, and the channel provided in one embodiment of this application; Figure 8 A simulated flow curve of a sample under test under alternating electric field excitation, provided as an embodiment of this application; Figure 9 A diagram showing the position of microspheres as a function of an electric field during sample mixing, provided as an embodiment of this application.

[0019] Figure label: 1000-Drive assembly; 11-Rack; 12-Button; 13-Gear set; 131-First double gear; 132-Second double gear; 133-Third double gear; 134-Single-stage gear; 14-Reset component; 2000 - Triboelectric nanogenerator; 20 - Main shaft; 21 - Friction ring; 211 - Conductive layer; 2111 - First electrode; 2112 - Second electrode; 22 - Planetary carrier; 221 - First carrier; 222 - Second carrier; 23 - Planetary gear; 231 - Friction layer; 232 - Shaft; 24 - Bearing; 3000-Power Management Module; 4000 - Microfluidic chip; 41 - Cover plate; 411 - Channel; 4111 - First branch; 4112 - Second branch; 4113 - Mixing section; 4114 - Inlet; 4115 - Outlet; 42 - Excitation electrode; 421 - First electrode group; 4211 - First electrode sheet; 422 - Second electrode group; 4221 - Second electrode sheet; 43 - Glass slide; 01-First receiving compartment; 011-First side wall; 0111-Mounting hole; 012-Second side wall; 02-Second receiving compartment; 03-Third receiving compartment; X - First direction; Y - Second direction. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description of the application is provided in conjunction with the accompanying drawings and embodiments.

[0021] The terminology used in the following embodiments is for the purpose of describing particular embodiments only and is not intended to be limiting of this application. As used in the specification and appended claims of this application, the singular expressions “a,” “an,” “the,” “the,” “the,” and “this” are intended to also include expressions such as “one or more” unless the context clearly indicates otherwise.

[0022] References to “an embodiment” or “a specific embodiment” as used in this specification mean that one or more embodiments of this application include a particular feature, structure, or characteristic described in connection with that embodiment. The terms “comprising,” “including,” “having,” and variations thereof mean “including, but not limited to,” unless otherwise specifically emphasized.

[0023] Microfluidics refers to a systematic technology that utilizes microchannels with characteristic scales ranging from tens to hundreds of micrometers to process or manipulate tiny fluids ranging from picoliters to nanoliters. This technology is characterized by miniaturization and integration, and one of its core features lies in the unique physical properties of fluids at the microscale, with a particularly crucial low Reynolds number. Leveraging these special fluid phenomena, microfluidics can achieve a range of microfabrications and micromanipulations that are difficult to accomplish using traditional methods.

[0024] In related technologies, micromixers are mainly divided into two categories based on their energy input method: passive and active. Passive micromixers rely on complex channel geometry to induce chaotic advection effects, offering advantages such as simple structure, convenient operation, and high throughput. However, their mixing efficiency is relatively low, and their structural design flexibility is insufficient. In contrast, active micromixers significantly improve mixing efficiency by introducing external energy fields such as acoustic, magnetic, and electric fields to actively disturb the fluid interface. Among these, electrically driven micromixers demonstrate outstanding potential due to their rapid response, precise control, and non-invasive operation. They achieve precise manipulation of fluids, particles, and biomolecules under the influence of an external electric field through mechanisms such as electroosmotic flow, electrophoresis, and dielectrophoresis. However, these electrically driven micromixers require high-frequency, high-voltage power supplies. These power supplies are bulky and consume a lot of power, resulting in poor integration and a large footprint for the micromixers. Furthermore, high-power operation can easily lead to electrode passivation, causing contamination of the test liquid and affecting the accuracy of the test results.

[0025] Triboelectric nanogenerators (TENGs) are energy harvesting devices that convert mechanical energy into electrical energy through triboelectric effect and electrostatic induction coupling. Their core power generation principle lies in utilizing the charge transfer generated by the contact friction between different material surfaces, which drives electrons to move directionally through electrodes and wires to generate electrical energy. This technology features small size, simple structure, lightweight, easy maintenance, and strong environmental adaptability. In terms of output characteristics, TENGs possess high voltage output capability, with continuous output voltages reaching several kilovolts, meeting the specific high-voltage power supply requirements of microfluidic applications.

[0026] In view of this, embodiments of this application provide a self-powered microfluidic mixing device based on the power generation principle of triboelectric nanogenerators. This device aims to solve the problems of large device size, low integration, and easy electrode passivation caused by the reliance on external high-voltage power supplies in existing microfluidic systems, while also overcoming the technical challenge of low mixing efficiency caused by molecular diffusion at the microscale.

[0027] Figure 1 This is a schematic diagram of a self-powered microfluidic hybrid device based on a triboelectric nanogenerator, provided as an embodiment of this application. Figure 1 As shown, an embodiment of this application provides a self-powered microfluidic hybrid device based on a triboelectric nanogenerator, comprising a power supply component and a microfluidic chip 4000. The power supply component includes a triboelectric nanogenerator 2000 and a power management module 3000. The triboelectric nanogenerator 2000 and the microfluidic chip 4000 are electrically connected to the power management module 3000, which rectifies and stores the electrical energy generated by the triboelectric nanogenerator 2000. The microfluidic chip 4000 includes excitation electrodes 42, which are an asymmetric coplanar electrode array. The excitation electrodes 42 are used to excite the liquid to be tested in the microfluidic chip 4000 to generate a secondary flow. The power management module 3000 is electrically connected to the excitation electrodes 42, providing them with a driving voltage.

[0028] In the above embodiments, the triboelectric nanogenerator 2000 can efficiently convert low-frequency mechanical energy into high-frequency transient pulse high voltage. After voltage regulation and amplitude modulation by the power management module 3000, it provides controllable high-voltage drive pulses to the microfluidic chip, thereby achieving precise control of fluids without the need for an external power supply. Because the triboelectric nanogenerator 2000 is self-powered, the device is free from dependence on traditional high-voltage power supplies and cables, resulting in a more compact, smaller, more integrated, and space-saving overall structure, while also offering good safety and portability. Furthermore, the triboelectric nanogenerator 2000 has low power consumption, making it less likely to cause passivation of the excitation electrode 42 within the microfluidic chip 4000, effectively reducing the risk of sample contamination. The excitation electrode 42 employs an asymmetric coplanar electrode array. Under the action of a high-voltage transient pulse electric field, it causes interfacial charge relaxation and concentration gradient polarization at the interface of the two phases of the test liquid due to differences in ionic characteristics, generating interfacial tangential electrical stress and permeation flow, inducing the formation of transverse secondary flow and interfacial disturbances, thereby achieving controllable expansion of the interfacial area and improved mass transfer efficiency.

[0029] Figure 2 This is a schematic diagram of the structure of a triboelectric nanogenerator provided in one embodiment of this application. Figure 3 This is a top view of a triboelectric nanogenerator provided as an embodiment of this application. Figure 2 and Figure 3 As shown, in one specific embodiment, the triboelectric nanogenerator 2000 is a planetary triboelectric nanogenerator, which includes a rotor assembly and a friction ring 21. The rotor assembly is disposed inside the friction ring 21 and is coaxially arranged with the friction ring 21.

[0030] The rotor assembly includes a planet carrier 22 and multiple planet gears 23, which are rotatably mounted on the planet carrier 22. The outer walls of the planet gears 23 are provided with friction layers 231. The planet carrier 22 drives the planet gears 23 to rotate, enabling the planet gears 23 to achieve a combined rotation-revolution motion. During rotation, the friction layers 231 contact or separate from the friction rings 21, generating electrical signals.

[0031] In a preferred embodiment, the triboelectric nanogenerator 2000 may include four planetary gears 23, each planetary gear 23 having a cylindrical roller structure and a friction layer 231 on its outer wall. The cylindrical roller-type planetary gears 23 have a large surface area, which increases the contact area with the friction ring 21, thereby improving power generation efficiency. The planetary gears 23 are evenly distributed along the circumference of the planetary carrier 22 to ensure that the planetary carrier 22 is under balanced forces.

[0032] The planetary carrier 22 includes a main shaft 20 and a first carrier 221 and a second carrier 222 arranged opposite to each other. The first carrier 221 and the second carrier 222 are arranged along the axial direction of the main shaft 20 and are press-fitted to the main shaft 20 to achieve coaxial and synchronous rotation of the main shaft 20, thereby ensuring that the axial direction of the planetary gears 23 is the same as that of the main shaft 20 within the error range. The planetary gears 23 are connected between the first carrier 221 and the second carrier 222 via a rotating shaft 232. The rotating shaft 232 can be made of bearing steel (CGr15) with a surface roughness Ra≤0.32μm to effectively suppress the frictional charge noise between the planetary gears 23 and the rotating shaft 232. The center distance tolerance of the planetary gears 23 is controlled within ±20μm.

[0033] In one embodiment, the first frame 221, the second frame 222, and the main shaft 20 can be an integrally formed structure.

[0034] To reduce the friction between the planetary gear 23 and the shaft 232 during rotation, in one embodiment, the planetary gear 23 is fixedly connected to the shaft 232, and a bearing 24 is provided between the shaft 232 and the planet carrier 22. Specifically, a bearing 24 is provided at the connection between one end of the shaft 232 and the first carrier 221, and a bearing 24 is also provided at the connection between the other end of the shaft 232 and the second carrier 222. The bearing 24 can be an MR52-ZZ P5 stainless steel miniature bearing.

[0035] In one embodiment, the planetary gear 23 is floatingly mounted on the planet carrier 22 to adjust the relative position of the planetary gear 23 and the friction ring 21, ensuring that the planetary gear 23 and the conductive layer 211 remain at the same height. Floating mounting means that a gap is provided between the planetary gear 23 and both the first carrier 221 and the second carrier 222, allowing the planetary gear 23 to move along its axial direction.

[0036] In one embodiment, the friction layer 231 may be made of an electron-electron-electron-electron-electron copolymer (FEP), polyimide, and polytetrafluoroethylene. The friction layer 231 may also be made of other electron-electron ...

[0037] In one specific embodiment, the friction layer 231 can be an FEP film with a thickness of 100 μm.

[0038] In one embodiment, the friction ring 21 may be made of a material that readily loses electrons, such as copper, aluminum, or other materials that readily lose electrons and are conductive. This application does not limit the specific material of the friction ring 21.

[0039] In one embodiment, the friction ring 21 is an interdigitated electrode structure, which includes an alternately arranged first electrode 2111 and a second electrode 2112. The first electrode 2111 and the second electrode 2112 can be made of copper foil with a thickness of 100 μm, and the interdigitated electrode pattern is formed on the copper foil by laser etching process.

[0040] In the above embodiments, the number of planetary gears 23 can be four. In other embodiments, the number of planetary gears 23 can also be three, five, six, eight, etc. It is necessary to ensure that the number of interdigitated electrode pairs with the friction ring 21 is 1:1. This application does not impose specific limitations.

[0041] In one embodiment, the friction layer 231 and the friction ring 21 have a gap. Specifically, an air gap of 0.2-0.5 mm is maintained between the surface of the friction layer 231 and the surface of the friction ring 21. This design significantly reduces solid friction loss and increases the effective contact area through an intermittent contact-separation mechanism, thereby increasing the charge transfer amount per cycle.

[0042] In another embodiment, the inner wall of the friction ring 21 may be provided with a conductive layer 211, which is an interdigitated electrode structure. In this embodiment, the friction ring 21 can be a carrier for the conductive layer 211. When the planet carrier 22 rotates, the friction layer 231 on the outer wall of the planet gear 23 contacts or separates from the conductive layer 211 to generate an electrical signal.

[0043] Figure 4 This is a schematic diagram of the structure of a driving component provided in one embodiment of this application, combined with... Figure 1 and Figure 4 In one embodiment, the self-powered microfluidic hybrid device based on a triboelectric nanogenerator further includes a drive assembly 1000, which is connected to the triboelectric nanogenerator 2000 and drives the planetary carrier 22 of the triboelectric nanogenerator 2000 to rotate, thereby generating an electrical signal. The drive assembly 1000 includes a rack 11, a button 12, and a gear set 13. The button 12 is fixedly connected to the rack 11, and the rack 11 meshes with the gear set 13. The button 12 is movable along a first direction X to drive the planetary carrier 22 to rotate.

[0044] In one embodiment, the gear set 13 includes a first double gear 131, a second double gear 132, a third double gear 133, and a single-stage gear 134. The first double gear 131 meshes with the rack 11, the first double gear 131 and the third double gear 133 mesh with the second double gear 132 respectively, and the single-stage gear 134 meshes with the third double gear 133. The rotor assembly is fixedly connected to the single-stage gear 134. A double gear refers to a gear consisting of two gears coaxially combined, including a large gear and a small gear. Specifically, the main shaft 20 is rigidly sleeved coaxially with the single-stage gear 134, and the shaft end of the main shaft 20 adopts a D-shaped flat structure to ensure that there is no relative slippage between the main shaft 20 and the single-stage gear 134 under high-speed forward and reverse rotation conditions.

[0045] Gear set 13 converts low-frequency linear mechanical excitation into high-speed rotational kinetic energy. The transmission path is as follows: rack 11 meshes with the pinion of the first double gear 131, which is supported by a steel shaft. The large gear of the first double gear 131 meshes with the pinion of the second double gear 132, which is also supported by a steel shaft. The large gear of the second double gear 132 meshes with the pinion of the third double gear 133, which is also supported by a steel shaft. Finally, the large gear of the third double gear 133 meshes with a single-stage gear 134, which drives the main shaft 20 of the planetary triboelectric nanogenerator 2000 to rotate. As a speed-increasing component, gear set 13, through the progressive speed increase of the three-stage double gears, enables the triboelectric nanogenerator 2000 to rotate at high speed, thereby significantly improving power generation efficiency.

[0046] In one embodiment, the gear ratio of the gear set 13 can be set to 1:22, thereby converting the linear motion of the key press from 0.2Hz to 0.9Hz into a high-speed rotation from 25.5Hz to 55Hz, with a single-cycle energy capture efficiency of not less than 68%. This enables the drive assembly 1000 to complete efficient energy capture and frequency upscaling within a single finger pressure stroke. The drive assembly 1000 employs a control-controlled gear acceleration system to convert the high-speed torque output by the planetary triboelectric nanogenerator 2000 into a high-amplitude transient pulse current, providing AC high-voltage power to the subsequent power management module 3000.

[0047] Combination Figure 1 and Figure 4In one embodiment, the self-powered microfluidic hybrid device based on a triboelectric nanogenerator further includes a housing with a first receiving chamber 01, into which a drive assembly 1000 is mounted. The first receiving chamber 01 includes a first sidewall 011 and a second sidewall 012 disposed opposite each other along a first direction X. The second sidewall 012 is located inside the device, and the first sidewall 011 is the outer wall of the housing. The first sidewall 011 has a mounting hole 0111. A button 12 and a rack 11 are inserted into the mounting hole 0111 and slide along the first direction X. This first direction X can be perpendicular to the axial direction of the planetary carrier 22. In the initial state, the button 12 is spaced a preset distance from the second sidewall 012, and pressing the button 12 brings it closer to the second sidewall 012. A reset member 14 is provided between the button 12 and the second sidewall 012. The reset member 14 is used to apply a reset force to the button 12, moving it away from the second sidewall 012 and towards the first sidewall 011, i.e., driving the button 12 to move outward from the housing. Specifically, the reset member 14 can be a spring. Button 12 is a hollow cylinder with a spring housed within it. One end of the spring is connected to the side wall of the button near the outer surface of the housing, while the other end abuts against the second side wall 012 of the first receiving chamber 01. Part of the spring is located within button 12, and the hollow cylinder of button 12 restricts the spring from bending laterally. Button 12, rack 11, and spring form an integrated reciprocating linear motion pair. The operator's single press frequency is 0.2-0.9Hz, with a stroke of 2-17mm. The elastic potential energy stored in the spring during the return stroke of button 12 can be partially transferred to rack 11, reducing the return idle stroke. The gear set 13 uses a 20° pressure angle and a modified tooth tip structure, which can control the tooth backlash to within 0.05mm, effectively suppressing high-frequency reverse backlash and ensuring that the triboelectric nanogenerator 2000 obtains bidirectional, continuous, and low-noise mechanical input.

[0048] In one embodiment, the housing further includes a second receiving compartment 02 and a third receiving compartment 03. The second receiving compartment 02 is located below the first receiving compartment 01 and is used to receive the triboelectric nanogenerator 2000. The third receiving compartment 03 is located to the side of the first receiving compartment 01 and is used to receive the power management module 3000.

[0049] Figure 5 A circuit diagram of a power management module provided for one embodiment of this application. (See diagram below.) Figure 5 As shown, in one embodiment, the power management module 3000 includes a full-bridge rectifier unit, a capacitor, and a trigger switch. The power management module 3000 is used to rectify and store the high-frequency pulsed electrical energy output from the triboelectric nanogenerator 2000. When the stored electrical energy reaches a set threshold, the trigger switch causes the electrical energy to be released instantaneously, thereby providing a controllable high-voltage drive pulse current to the microfluidic chip 4000.

[0050] In one specific embodiment, the capacitor is an aluminum electrolytic capacitor (25V, 22μF), the full-bridge rectifier unit is model DB107, and the threshold is set to 6V~10V.

[0051] In one embodiment, the trigger switch can be a trigger-type switch, such as a mechanical micro switch.

[0052] Figure 6 A schematic diagram of the structure of a microfluidic chip provided in one embodiment of this application is shown below. Figure 6 As shown, in one embodiment, the microfluidic chip 4000 further includes a cover plate 41 and a glass slide 43 stacked along a second direction Y. The cover plate 41 has a channel 411 for accommodating the sample to be tested, which can flow along the length of the channel 411. An excitation electrode 42 is located between the cover plate 41 and the glass slide 43. The excitation electrode 42 is electrically connected to and controlled by the power management module 3000 to induce a secondary flow in the sample to be tested within the microchannel, thereby achieving controllable manipulation of the microscale liquid-liquid interface. The aforementioned second direction Y can be the axial direction of the planetary carrier.

[0053] In one embodiment, the glass slide 43 is a sodium-calcium glass slide, and the cover plate 41 is made of polydimethylsiloxane (PDMS). The cover plate 41, the excitation electrode 42, and the glass slide 43 are bonded together.

[0054] Figure 7 This is a schematic diagram of the structure of the first electrode sheet, the second electrode sheet, and the channel provided in one embodiment of this application. Figure 8 A simulated flow curve of a sample under test under alternating electric field excitation, provided as an embodiment of this application.

[0055] like Figure 7 As shown, in one embodiment, the excitation electrode 42 is an asymmetric coplanar microelectrode array. Specifically, the excitation electrode 42 includes a first electrode group 421 and a second electrode group 422. Along the width direction of the channel 411, the first electrode group 421 and the second electrode group 422 are respectively disposed on both sides of the channel 411. The first electrode group 421 includes a plurality of first electrode pieces 4211 spaced apart and arranged in parallel along the length direction of the channel 411. The second electrode group 422 includes a plurality of second electrode pieces 4221 spaced apart and arranged in parallel along the length direction of the channel. The first electrode pieces 4211 and the second electrode pieces 4221 are arranged one-to-one along the width direction of the channel, forming multiple electrode pairs. At least a portion of the first electrode pieces 4211 and at least a portion of the second electrode pieces 4221 are located within the channel 411 and are in direct contact with the liquid to be measured. Along the width direction of channel 411, there is a gap between the first electrode plate 4211 and the second electrode plate 4221 in each electrode pair. When energized, an electric field is formed between the first electrode plate 4211 and the second electrode plate 4221 in each electrode pair.

[0056] Along the length of channel 411, the gaps between multiple electrode pairs are staggered. Specifically, along the length of channel 411, the centerlines of the gaps between multiple electrode pairs intersect each other, rather than being on the same straight line. Figure 7 As shown, the center lines of the gaps between the first, third, and fifth electrode pairs overlap, and the center lines of the gaps between the second and fourth electrode pairs overlap. Figure 8 This is a simulation diagram of the flow curve of a sample under test under alternating electric field excitation provided in one embodiment of this application. The staggered arrangement of multiple electrode pairs generates an alternating electric field within channel 411, thereby inducing interfacial fluctuations in the sample under test and exciting... Figure 8 The secondary flow shown improves the mixing efficiency of the sample under test.

[0057] The first electrode group 421 can be connected to the input terminal of the power management module 3000, and the second electrode group 422 can be connected to the output terminal of the power management module 3000.

[0058] In one specific embodiment, a 1.0 mm thick sodium-calcium glass slide is selected, and its surface is pretreated with oxygen plasma (80 W, 25 s), reducing the contact angle to below 10°, which can improve the bonding strength with the cover plate 41. Indium tin oxide (ITO) of 220 ± 50 nm is sputtered on the front side of the glass slide 43, and an asymmetric coplanar electrode pair, i.e., the excitation electrode 42, is formed by laser etching. The finger width A of the first electrode plate 4211 and the second electrode plate 4221 is 300 μm, and the misalignment B of two adjacent electrode pairs is 20 μm.

[0059] In one embodiment, channel 411 includes an inlet section and a mixing section 4113. The inlet end has multiple branch structures, each of which is connected to the mixing section. The multiple branch structures are used to inject various test samples.

[0060] In one embodiment, the multiple branch structures include a first branch 4111 and a second branch 4112, which are arranged at an angle. The ends of the first branch 4111 and the second branch 4112 are provided with liquid inlets 4114. The mixing section 4113 has a liquid outlet 4115 at its end opposite to the liquid inlet section.

[0061] The cover plate 41 can be 4 mm thick. Its preparation process involves mixing the prepolymer and curing agent in a 10:1 ratio and curing at 80°C for 45 minutes. Its lower surface is then molded using an SU-8 mold to obtain a mixed section 4113 with a cross-section of 200 μm (height) × 600 μm (width). After activation by oxygen plasma, the glass slide 43 and cover plate 41 are immediately aligned and pressed together, followed by heat annealing at 110°C for 10 minutes to achieve irreversible bonding, resulting in a pressure resistance of ≥250 kPa for the cover plate 41.

[0062] In one embodiment, the first branch 4111 and the second branch 4112 form a 90° angle.

[0063] In other embodiments, the first branch 4111 and the second branch 4112 may also form an angle of 60°, 120°, etc., and this application does not impose specific limitations.

[0064] Two-phase aqueous solutions were injected into the first branch 4111 and the second branch 4112 through the inlet 4114 of a stainless steel L-shaped syringe with an outer diameter of 0.6 mm, driven by a 1-100 μL / min injection pump. A stable laminar liquid-liquid interface was formed in the mixing section 4113, with a Reynolds number Re < 5, ensuring no turbulent mixing in the initial state. When the energy storage capacitor voltage of the power management module 3000 reached the set threshold of 7.0V, the operator triggered the mechanical microswitch (trigger switch) of the power management module 3000, and the excitation electrode 42 established an in-plane gradient electric field of 7.0Vpp. The interface charge relaxation and concentration gradient polarization driven by the difference in ionic characteristics at the liquid-liquid interface generated interfacial tangential electrical stress and permeation flow, inducing the formation of reverse vortices (secondary flow) on both sides of the interface. High-speed imaging showed that the original interface underwent a deflection of greater than 2.07° within 400 ms, accompanied by a stretching-folding process, and the mixing efficiency of the two-phase solution exceeded 90%.

[0065] Figure 9 This is a diagram showing the position of microspheres as a function of an electric field, according to one embodiment of this application. Figure 9 As shown, in one embodiment, polystyrene (PS) microspheres were added to sample one for labeling, while no polystyrene microspheres were added to sample two. Sample one was injected into the first branch 4111, and sample two was injected into the second branch 4112. The mixed samples flowed into the mixing section 4113 of channel 411. When the power management module 3000 detected that the capacitor energy storage voltage reached a set threshold, it triggered the switch to close, and a transient pulse electric field was applied to the excitation electrode 42, forming a transient gradient electric field at the liquid-liquid interface. The polystyrene microspheres in the central region of the mixing section 4113 were first driven to migrate towards the cathode by transverse electroosmotic flow (EOF). After adsorbing excess anions in the cathode region, the surface charge reversed to negative, and then entered the reverse equilibrium region of EOF and electrophoresis (EP) and decelerated to zero. Subsequently, under the dominance of EP, they turned back towards the anode, forming a reversible motion trajectory of "cathode-stationary-anode". This visible trajectory of the microspheres mapped and amplified the transient migration process of invisible ions in the microfluidic in real time, realizing the visualization of particle dynamic manipulation and ion transport.

[0066] The working process of the self-powered microfluidic hybridization device based on triboelectric nanogenerator in this application is as follows: When the operator presses button 12, the low-frequency linear displacement excitation applied by the fingertip is converted into high-speed rotational kinetic energy through a spring-rack-gear coupling mechanism (i.e., drive component 1000), achieving efficient collection of low-frequency mechanical energy and frequency upscaling. The output end of drive component 1000 is coaxially connected to a planetary gear triboelectric nanogenerator to match the latter's threshold requirement for excitation frequency.

[0067] The planetary gear triboelectric nanogenerator adopts a planetary gear train-friction layer coupling architecture. The planet carrier 22, as the active component, receives the torque input from the drive component 1000 and converts the mechanical energy of the high-speed rotation of the planetary gears 23 into transient pulse electrical signals with high frequency, high voltage, and micro-charge in real time, and then sends them to the power management module 3000.

[0068] The power management module 3000 rectifies and stores the high-frequency pulsed electrical energy output by the triboelectric nanogenerator, and releases it instantaneously after reaching a threshold, providing a controllable high-voltage drive pulse for the microfluidic chip 4000.

[0069] Under the action of a high-voltage transient pulse electric field, the interface charge relaxation and concentration gradient polarization at the liquid-liquid interface of the two-phase sample in the microfluidic chip 4000 are driven by the difference in ionic characteristics, generating interfacial tangential electric stress and permeation flow, inducing the formation of transverse secondary flow and interface disturbance, thereby achieving controllable expansion of the liquid-liquid interface area and a step-wise improvement in mass transfer efficiency.

[0070] The self-powered microfluidic mixing device based on a triboelectric nanogenerator described in this application can be applied to environmental monitoring, materials synthesis, and biochemical analysis scenarios, such as sweat detection. It precisely regulates the instability of the liquid-liquid interface through controllable high-voltage pulses, instantaneously exciting interfacial fluctuations and secondary flow coupling, significantly reducing the mass transfer boundary layer thickness, and achieving millisecond-level efficient transmembrane transport of target ions at the phase interface. This enables the enrichment of trace pollutants, controllable assembly of nanoparticles, or acceleration of biochemical reactions.

[0071] In the description of the embodiments of this application, it should be understood that the terms "upper", "lower", "top", "bottom", "left", "right", "front", "rear", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of the application and simplifying the description, and do not indicate or imply that the device or unit referred to must have a specific orientation or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of the application.

[0072] Obviously, those skilled in the art can make various modifications and variations to this application without departing from the spirit and scope of this application. Therefore, if such modifications and variations fall within the scope of the claims of this application and their equivalents, this application also intends to include such modifications and variations.

Claims

1. A self-powered microfluidic hybrid device based on a triboelectric nanogenerator, characterized in that, Including power supply components and microfluidic chips, among which, The microfluidic chip includes an excitation electrode, which is an asymmetric coplanar electrode array. The excitation electrode is used to excite the liquid to be tested in the microfluidic chip to generate a secondary flow. The power supply component includes a triboelectric nanogenerator and a power management module. The triboelectric nanogenerator and the excitation electrode are respectively electrically connected to the power management module. The power management module is used to store the electrical energy generated by the triboelectric nanogenerator and provide electrical energy to the excitation electrode.

2. The self-powered microfluidic hybrid device based on a triboelectric nanogenerator according to claim 1, characterized in that, The triboelectric nanogenerator includes a rotor assembly and a friction ring. The rotor assembly is disposed inside the friction ring. The rotor assembly includes a planet carrier and multiple planetary gears. The multiple planetary gears are rotatably mounted on the planet carrier. The outer wall of the planetary gears is provided with a friction layer.

3. The self-powered microfluidic hybrid device based on a triboelectric nanogenerator according to claim 2, characterized in that, The friction ring has an interdigitated electrode structure, comprising an alternating first electrode and a second electrode.

4. The self-powered microfluidic hybrid device based on a triboelectric nanogenerator according to claim 2, characterized in that, The friction layer has a gap with the friction ring.

5. The self-powered microfluidic hybrid device based on a triboelectric nanogenerator according to claim 2, characterized in that, The friction layer is any one of fluorinated ethylene propylene copolymer, polyimide, and polytetrafluoroethylene.

6. The self-powered microfluidic hybrid device based on a triboelectric nanogenerator according to claim 2, characterized in that, It also includes a drive assembly that is connected to the triboelectric nanogenerator. The drive assembly includes a rack, a button, and a gear set. The button is fixedly connected to the rack, and the rack meshes with the gear set. The button is used to drive the planetary carrier to rotate so that the friction layer contacts or separates from the friction ring to generate an electrical signal.

7. The self-powered microfluidic hybrid device based on a triboelectric nanogenerator according to claim 6, characterized in that, The gear set includes a first double gear, a second double gear, a third double gear, and a single-stage gear. The first double gear meshes with the rack. The first double gear and the third double gear mesh with the second double gear, respectively. The single-stage gear meshes with the third double gear. The rotor assembly is fixedly connected to the single-stage gear.

8. The self-powered microfluidic hybrid device based on a triboelectric nanogenerator according to claim 6, characterized in that, It also includes a housing having a first receiving compartment, the drive assembly being mounted in the first receiving compartment, the first receiving compartment including a first sidewall and a second sidewall disposed opposite to each other along a first direction, the first sidewall having a mounting hole; the button being inserted into the mounting hole, the button being slidable along the first direction; a reset member being provided between the button and the second sidewall, the reset member being used to drive the button to reset in a direction away from the second sidewall.

9. The self-powered microfluidic hybrid device based on a triboelectric nanogenerator according to claim 1, characterized in that, The microfluidic chip includes a glass slide and a cover plate stacked together. The excitation electrode is located between the glass slide and the cover plate. The cover plate has a channel for accommodating the sample to be tested.

10. The self-powered microfluidic hybrid device based on a triboelectric nanogenerator according to claim 9, characterized in that, The excitation electrode includes a first electrode group and a second electrode group, which are respectively disposed on both sides of the channel along the width direction of the channel. The first electrode group includes a plurality of first electrode pieces spaced apart along the length direction of the channel, and the second electrode group includes a plurality of second electrode pieces spaced apart along the length direction of the channel. The first electrode pieces and the second electrode pieces are arranged in a one-to-one correspondence along the width direction of the channel to form a plurality of electrode pairs. Along the width direction of the channel, there is a gap between the first electrode piece and the second electrode piece in each electrode pair, and along the length direction of the channel, the gaps corresponding to the plurality of electrode pairs are arranged in an alternating manner.

11. The self-powered microfluidic hybrid device based on a triboelectric nanogenerator according to claim 9, characterized in that, The channel includes an inlet section and a mixing section that are connected to each other. The inlet section has multiple branch structures, and each branch structure is connected to the mixing section.

12. The self-powered microfluidic hybrid device based on a triboelectric nanogenerator according to claim 11, characterized in that, The plurality of branch structures include a first branch and a second branch, wherein the first branch and the second branch are arranged at an angle.

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