A flexible thin film ion concentration and flow sensor and method of measuring

Abstract

The application discloses a flexible thin film ion concentration and flow sensor and a measuring method thereof. The sensor comprises a sensor body and a microprocessor. The sensor body comprises, from top to bottom, a packaging layer, a pore pressure measuring layer, a three-electrode layer and a substrate layer which are sequentially stacked. The flow channel holes of the packaging layer, the flow channel holes of the pore pressure measuring layer, the upper flow channel grooves of the three-electrode layer, the flow channel holes of the three-electrode layer and the lower flow channel grooves of the substrate layer are sequentially communicated to form a micro flow channel. The output leads of the pore pressure measuring layer and the three-electrode layer are led out from the layered stacked structure and connected with the microprocessor. The microprocessor is provided with a calibration model of pore pressure and flow rate and a calibration model of current and concentration, which are used for calculating the flow rate of liquid and the concentration of target ions in the liquid and finally calculating the flux of target ions in the liquid. The sensor body of the application is of a flexible structure, integrates concentration and flow detection, and is suitable for online monitoring and quantitative evaluation in a porous medium seepage process.

Description

Technical Field

[0001] This invention relates to the field of sensor technology, specifically to a flexible thin-film ion concentration and flow sensor and its measurement method. Background Technology

[0002] Currently, in the seepage process of porous media (such as soil, rock, tissue, or porous membranes), the seepage-driven convection-diffusion process determines the spatiotemporal distribution of solute flux and total ion content. Traditional electrochemical three-electrode systems (working electrode WE / reference electrode RE / counter electrode CE) are often used for in-situ detection of target ions in liquids, but it is difficult to obtain pore pressure or seepage velocity at the same location simultaneously, thus making it impossible to directly convert "concentration-time" information into "flux / total content". Summary of the Invention

[0003] The technical problem to be solved by the present invention is to provide a flexible thin-film ion concentration and flow sensor and its measurement method. The sensor body has a flexible structure and integrates concentration and flow detection, which is suitable for online monitoring and quantitative evaluation in porous media seepage processes.

[0004] The technical solution of this invention is as follows: A flexible thin-film ion concentration and flow sensor includes a sensor body and a microprocessor. The sensor body includes an encapsulation layer, a pore pressure measurement layer, a three-electrode layer, and a substrate layer stacked sequentially from top to bottom. Each of the encapsulation layer, pore pressure measurement layer, and three-electrode layer has vertically connected flow channels, with the flow channels on the encapsulation layer and pore pressure measurement layer completely overlapping and communicating. An upper flow channel groove is formed on the top surface of the three-electrode layer, and the bottom end of the upper flow channel hole in the pore pressure measurement layer and the top end of the upper flow channel hole in the three-electrode layer are respectively connected to the upper flow channel groove. A lower flow channel groove is formed on the top surface of the substrate layer, and the bottom end of the upper flow channel hole in the three-electrode layer is connected to one end of the lower flow channel groove. The other end of the lower flow channel groove extends to the edge of the substrate layer, thereby forming a microchannel by sequentially connecting the flow channels of the encapsulation layer, the pore pressure measurement layer, the upper flow channel groove of the three-electrode layer, the flow channel hole of the three-electrode layer, and the lower flow channel groove of the substrate layer from top to bottom. The output leads of the pore pressure measurement layer and the three-electrode layer are both led out from the layered stacked structure and connected to the microprocessor. The microprocessor is equipped with calibration models for pore pressure and flow rate, as well as calibration models for current and concentration. The microprocessor measures the pore pressure through the pore pressure measurement layer and then combines it with the calibration models for pore pressure and flow rate to obtain the flow rate of the liquid. The microprocessor collects the current through the three-electrode layer and then combines it with the calibration models for current and concentration to obtain the concentration of the target ion in the liquid. The microprocessor combines the flow rate of the liquid and the concentration of the target ion in the liquid to calculate the flux of the target ion in the liquid.

[0005] Both the encapsulation layer and the pore pressure measurement layer are provided with multiple vertically penetrating flow channels, and the multiple flow channels on the encapsulation layer and the pore pressure measurement layer are completely overlapping and connected.

[0006] Both the encapsulation layer and the pore pressure measurement layer have lead-out holes near their edges. A metal pad is provided on the top surface of the encapsulation layer at the lead-out hole. The output lead of the pore pressure measurement layer passes through the lead-out hole of the encapsulation layer and is connected to the metal pad. The output lead of the three-electrode layer passes through the lead-out holes of the pore pressure measurement layer and the encapsulation layer in sequence and is connected to the metal pad.

[0007] Both the encapsulation layer and the substrate layer are made of polyimide film.

[0008] The pore pressure measuring layer is provided with a pressure-sensitive area, which is composed of an upper composite film, a lower composite film, and a flexible film disposed between the upper and lower composite films. The upper composite film is composed of an upper silver ion layer and a fluorinated ethylene propylene copolymer (FEP) layer stacked vertically, and the lower composite film is composed of a polyethylene terephthalate (PET) layer and a lower silver ion layer stacked vertically. Output leads are connected to both the upper and lower composite films. The flexible film includes a polydimethylsiloxane (PDMS) matrix and an e-PTFE fiber skeleton embedded in the PDMS matrix, including an upper PDMS layer, The system consists of a lower PDMS layer, multiple primary PDMS columns and multiple secondary PDMS columns positioned between the upper and lower PDMS layers. The primary PDMS columns are arranged in a matrix, as are the secondary PDMS columns. A secondary PDMS column is positioned between any two adjacent primary PDMS columns. The top and bottom of each primary PDMS column are fixedly connected to the upper and lower PDMS layers, respectively. The bottom of each secondary PDMS column is fixedly connected to the lower PDMS layer. A gap is left between the top of each secondary PDMS column and the upper PDMS layer. The pore pressure measurement layer, except for the pressure-sensitive area, is made of polydimethylsiloxane.

[0009] The thickness of the upper and lower silver ion layers is 9-11 μm, the thickness of the FEP and PET layers is 7-9 μm, the thickness of the upper and lower PDMS layers is 9-11 μm, the height of the primary PDMS pillar is 70-90 μm, and the height of the secondary PDMS pillar is 30-50 μm.

[0010] The three-electrode layer is located at the bottom of the upper flow channel and includes a working electrode, a reference electrode, and a counter electrode. The working electrode is a Cr / Au electrode, a Cu / Au electrode, or a graphene electrode, and is arranged in a serpentine semi-circular structure. The surface of the working electrode is modified with Prussian blue mediator and an ion-selective film. The reference electrode is an Ag / AgCl electrode coated with polyvinyl butyral. The counter electrode is a gold electrode or a graphene electrode. Output leads are connected to the working electrode, the reference electrode, and the counter electrode.

[0011] The three-electrode layer is located at the bottom of the upper flow channel tank and is equipped with a temperature sensor and a pH electrode probe. Both the temperature sensor and the pH electrode probe are connected to output leads.

[0012] A method for measuring ion concentration and flow rate using a flexible thin-film ion concentration and flow rate sensor specifically includes the following steps: (1) The microprocessor acquires the pore pressure value P(t) measured by the pore pressure measurement layer in real time. The microprocessor has a built-in calibration model of pore pressure and flow velocity v(t)=K1(P(t)), where K1 is the fitting parameter of pore pressure and flow velocity, and v(t) is the flow velocity. The real-time flow velocity corresponding to the real-time pore pressure value is calculated by the calibration model of pore pressure and flow velocity. (2) The microprocessor calculates the volumetric flow rate Q(t) according to the following formula (1): Q(t)=v(t)S (1; In equation (1), S represents the effective cross-sectional area through which the liquid flows; (3) The microprocessor acquires the peak current i of the target ion measured by the three-electrode layer in real time. p (t), the microprocessor has a built-in calibration model for current and concentration c(t)=K2(i p (t)), K2 is the fitting parameter for current and concentration, and c(t) is the ion concentration. The ion concentration corresponding to the real-time peak current of the target ion is obtained by calculating the calibration model of current and concentration. (4) The microprocessor multiplies the volumetric flow rate by the ion concentration to calculate the flux of the target ion, as shown in the following formula (2): N(t)=c(t)Q(t) (2; In equation (2), N(t) represents the flux of the target ion, which is the molar flow rate through the effective cross section per unit time.

[0013] Advantages of this invention: (1) This invention is provided with a three-electrode layer and uses a three-electrode structure for ion concentration collection. The working electrode surface is modified with Prussian blue mediator to enhance the collection of specific ions (such as...). , The selectivity and sensitivity of the target ion (or heavy metal ion) are improved by modifying the ion-selective membrane to enhance the selectivity for the target ion and achieve the purpose of detecting the concentration of the target ion; the working electrode is set into a serpentine extended semi-circular structure to improve the bending reliability of the three-electrode structure and reduce the line resistance; the reference electrode is an Ag / AgCl electrode coated with polyvinyl butyral. Polyvinyl butyral is a hydrophilic polymer material that effectively prevents ion leakage and enhances solvent resistance.

[0014] (2) The pore pressure measurement layer of the present invention contains two types of PDMS columns of different heights, so that under small pressure, only the first-level PDMS column is stressed and easily deformed, thus achieving a high sensitivity response to low pressure. When the pressure increases to a certain extent, the second-level PDMS column also begins to contact and provide support, preventing the structure from collapsing instantly, thereby achieving a wide range of compression range. The pore pressure measurement layer is essentially a porous structure (with hollow interior). Compared with solid film, it has an extremely low Young's modulus and can support >50% strain. This allows it to better adapt to the deformation of soft materials such as soil or biological tissue, and will not affect the natural seepage of the measured environment due to the sensor being too hard. The flexible film of the pore pressure measurement layer is embedded with an e-PTFE fiber skeleton, making its tensile strength 13 times that of pure PDMS, solving the problem of easy tearing of porous structures.

[0015] (3) The present invention is provided with microchannels to control fluid flow, improve the refresh time and time resolution of the sensor, drive permeation in porous media, assist in the measurement of the spatiotemporal distribution of ion flux, improve the dynamic response of ion concentration measurement, and support high-sensitivity detection.

[0016] (4) The present invention establishes calibration models for pore pressure and flow velocity, as well as calibration models for current and concentration. Before the pore pressure measurement layer and the three-electrode layer are stacked, the model is calibrated to quickly realize the acquisition of flow velocity and concentration. Through real-time calculation, the "concentration-time" information is quickly converted into "flux / total". It is suitable for online monitoring and quantitative evaluation of porous media seepage process. Attached Figure Description

[0017] Figure 1 This is an exploded structural diagram of the sensor body of the present invention. The arrows in the diagram indicate the flow direction of the microchannels.

[0018] Figure 2 This is a plan view of the encapsulation layer of the present invention.

[0019] Figure 3 This is a schematic diagram of the structure of the pressure-sensitive region of the pore pressure measuring layer of the present invention.

[0020] Figure 4 This is a plan view of the three electrode layers of the present invention.

[0021] Figure 5 This is a plan view of the base layer of the present invention.

[0022] Reference numerals: 1-Encapsulation layer, 2-Pore pressure measurement layer, 3-Three-electrode layer, 4-Base layer, 5-Flow channel hole, 6-Upper flow channel groove, 7-Lower flow channel groove, 2A-Pressure sensitive area, 21-Upper silver ion layer, 22-FEP layer, 23-PET layer, 24-Lower silver ion layer, 25-Upper PDMS layer, 26-Lower PDMS layer, 27-Primary PDMS column, 28-Secondary PDMS column, 31-Working electrode, 32-Reference electrode, 33-Counter electrode, 34-Temperature sensor, 35-pH electrode sensor, 36-Output lead. Detailed Implementation

[0023] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0024] A flexible thin-film ion concentration and flow sensor includes a sensor body and a microprocessor; See Figure 1 The sensor body includes, from top to bottom, an encapsulation layer 1, a pore pressure measurement layer 2, a three-electrode layer 3, and a substrate layer 4, all stacked sequentially. Both the encapsulation layer 1 and the substrate layer 4 are made of polyimide (PI) film (100 μm thick). Encapsulation layer 1 (see...) Figure 2 Both the encapsulation layer 1 and the pore pressure measurement layer 2 (176 μm) have two vertically connected flow channel holes 5. The two flow channel holes 5 on the encapsulation layer 1 and the pore pressure measurement layer 2 are completely overlapping and connected. The three-electrode layer 3 (120 μm thick) has one vertically connected flow channel hole 5 and an upper flow channel groove 6. The bottom end of the upper flow channel hole 5 on the pore pressure measurement layer 2 and the top end of the upper flow channel hole 5 on the three-electrode layer 3 are connected to the upper flow channel groove 6, respectively. A lower flow channel groove 7 is formed on the top surface of the substrate layer 4 (see...). Figure 5 The bottom end of the upper flow channel hole 5 of the three electrode layer 3 is connected to one end of the lower flow channel groove 7, and the other end of the lower flow channel groove 7 extends to the edge of the substrate layer 4, so that the flow channel hole 5 of the encapsulation layer 1, the flow channel hole 5 of the pore pressure measurement layer 2, the upper flow channel groove 6 of the three electrode layer 3, the flow channel hole 5 of the three electrode layer 3, and the lower flow channel groove 7 of the substrate layer 7 are connected sequentially from top to bottom to form a microchannel. Both the encapsulation layer 1 and the pore pressure measurement layer 2 have lead-out holes near their edges. A metal pad is located on the top surface of the encapsulation layer 1 at the lead-out hole. The output lead of the pore pressure measurement layer 2 passes through the lead-out hole of the encapsulation layer 1 and connects to the metal pad. The output lead of the three-electrode layer 3 passes sequentially through the lead-out holes of the pore pressure measurement layer 2 and the encapsulation layer 1 and connects to the metal pad. The metal pad has a diameter of 1.2–1.5 mm and is compatible with ZIF (Zero Insertion Force Connector) and ACF (Anisotropic Conductive Film). Alternatively, conductive adhesive can be used for connection; the output leads of the pore pressure measurement layer 2 and the three-electrode layer 3 are led out through metal pads and connected to the microprocessor. The microprocessor is equipped with calibration models for pore pressure and flow rate, as well as calibration models for current and concentration. The microprocessor measures the pore pressure through the pore pressure measurement layer and then combines it with the calibration models for pore pressure and flow rate to obtain the flow rate of the liquid. The microprocessor collects the current through the three-electrode layer and then combines it with the calibration models for current and concentration to obtain the concentration of the target ion in the liquid. The microprocessor combines the flow rate of the liquid and the concentration of the target ion in the liquid to calculate the flux of the target ion in the liquid.

[0025] See Figure 3A pressure-sensitive region 2A is provided on the pore pressure measuring layer 2. The pressure-sensitive region 2A consists of an upper composite film, a lower composite film, and a flexible film disposed between the upper and lower composite films. The upper composite film is composed of an upper silver ion layer 21 and a fluorinated ethylene propylene copolymer (FEP) layer 22 stacked vertically. The FEP layer 22 is negatively corona-charged to act as an electret (charge density -1.1 mC / m², -20 kV, 3 The lower composite film is composed of a polyethylene terephthalate (PET) layer 23 and a lower silver ion layer 24 stacked on top of each other. Output leads are connected to both the upper and lower composite films. The flexible film includes a polydimethylsiloxane (PDMS) matrix and an e-PTFE fiber skeleton embedded in the PDMS matrix. It includes an upper PDMS layer 25, a lower PDMS layer 26, and multiple primary PDMS pillars 27 and multiple secondary PDMS pillars 28 disposed between the upper PDMS layer 25 and the lower PDMS layer 26. The primary PDMS pillars 27 are arranged in a matrix, and the secondary PDMS pillars 28 are also arranged in a matrix. Any two adjacent primary PDMS pillars 27... Each stage is equipped with a secondary PDMS column 28. The top and bottom of each primary PDMS column 27 are fixedly connected to the upper PDMS layer and the lower PDMS layer, respectively. The bottom of each secondary PDMS column 28 is fixedly connected to the lower PDMS layer. A gap is left between the top of each secondary PDMS column 28 and the upper PDMS layer. The thickness of the upper silver ion layer 21 and the lower silver ion layer 24 is 10 μm. The thickness of the FEP layer 22 and the PET layer 23 is 8 μm. The thickness of the upper PDMS layer 25 and the lower PDMS layer 26 is 10 μm. The height of the primary PDMS column is 80 μm, and the height of the secondary PDMS column is 40 μm. The pore pressure measurement layer 2, except for the pressure-sensitive area 2A, is made of PDMS. When an external pore pressure P is applied, the sensor body deforms, causing the upper PDMS layer 25 to compress the lower PDMS layer 26, thus changing the gap between the upper PDMS layer 25 and the lower PDMS layer 26. This disrupts the potential balance, causing electrons to flow from the lower electrode to the upper electrode (short-circuit state). When pressure P is released, the sensor body elastically rebounds. The electron flow resumes in the opposite direction, forming an alternating current / voltage signal. The formula for the open-circuit voltage (Voc) is: ,in, The electret charge density, is the dielectric constant of air.

[0026] See Figure 4 The upper flow channel groove 6 on the three electrode layer 3 ( Figure 4The depth of the groove (the area circled in the middle) is 60μm. At the bottom of the upper flow channel groove 6, there are a working electrode 31, a reference electrode 32, a counter electrode 33, a temperature sensor 34, and a pH electrode probe 35. The working electrode 31 is a graphene electrode, which is achieved by laser-induced grapheneization without the need for cleanroom processing. The target ions undergo an oxidation / reduction reaction with the working electrode 31. The working electrode 31 is set in a serpentine semi-circular structure. The surface of the working electrode 31 is modified with Prussian blue mediator and ion-selective film. The reference electrode 32 is used to provide a stable reference potential to avoid measurement drift. The reference electrode 32 is an Ag / AgCl electrode coated with polyvinyl butyral. The counter electrode is used to form a current loop and carry the current. The counter electrode 33 is a gold electrode or a graphene electrode. Output leads 36 are connected to the working electrode 31, the reference electrode 32, the counter electrode 33, the temperature sensor 34, and the pH electrode probe 35.

[0027] A method for measuring ion concentration and flow rate using a flexible thin-film ion concentration and flow rate sensor specifically includes the following steps: (1) The microprocessor acquires the pore pressure value P(t) measured by the pore pressure measurement layer 2 in real time. The microprocessor has a built-in calibration model of pore pressure and flow velocity v(t)=K1(P(t)), where K1 is the fitting parameter of pore pressure and flow velocity, and v(t) is the flow velocity. The real-time flow velocity corresponding to the real-time pore pressure value is calculated by the calibration model of pore pressure and flow velocity. (2) The microprocessor calculates the volumetric flow rate Q(t) according to the following formula (1): Q(t)=v(t)S (1; In equation (1), S represents the effective cross-sectional area through which the liquid flows; (3) The microprocessor acquires the peak current i of the target ion measured by the three-electrode layer 3 in real time. p (t), the microprocessor has a built-in calibration model for current and concentration c(t)=K2(i p (t)), K2 is the fitting parameter for current and concentration, and c(t) is the ion concentration. The ion concentration corresponding to the real-time peak current of the target ion is obtained by calculating the calibration model of current and concentration. (4) The microprocessor multiplies the volumetric flow rate by the ion concentration to calculate the flux of the target ion, as shown in the following formula (2): N(t)=c(t)Q(t) (2; In equation (2), N(t) represents the flux of the target ion, which is the molar flow rate through the effective cross section per unit time.

[0028] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A flexible thin-film ion concentration and flow sensor, characterized in that: The sensor includes a sensor body and a microprocessor. The sensor body includes an encapsulation layer, a pore pressure measurement layer, a three-electrode layer, and a substrate layer stacked sequentially from top to bottom. The encapsulation layer, the pore pressure measurement layer, and the three-electrode layer are all provided with vertically penetrating flow channels, and the flow channels on the encapsulation layer and the pore pressure measurement layer are completely overlapping and connected. An upper flow channel groove is formed on the top surface of the three-electrode layer. The bottom end of the upper flow channel hole in the pore pressure measurement layer and the top end of the upper flow channel hole in the three-electrode layer are respectively connected to the upper flow channel groove. A lower flow channel groove is formed on the top surface of the substrate layer. The bottom end of the upper flow channel hole in the three-electrode layer is connected to one end of the lower flow channel groove, and the other end of the lower flow channel groove extends to the edge of the substrate layer. Thus, the flow channels of the encapsulation layer, the flow channels of the pore pressure measurement layer, the upper flow channel groove of the three-electrode layer, the flow channels of the three-electrode layer, and the lower flow channel groove of the substrate layer are sequentially connected from top to bottom to form a microchannel. The pore pressure measuring layer is provided with a pressure-sensitive area, which is composed of an upper composite film, a lower composite film, and a flexible film disposed between the upper and lower composite films. The upper composite film is composed of an upper silver ion layer and a fluorinated ethylene propylene copolymer (FEP) layer stacked vertically, and the lower composite film is composed of a polyethylene terephthalate (PET) layer and a lower silver ion layer stacked vertically. Output leads are connected to both the upper and lower composite films. The flexible film includes a polydimethylsiloxane (PDMS) matrix and an e-PTFE fiber skeleton embedded in the PDMS matrix, including an upper PDMS layer, The system comprises a lower PDMS layer, multiple primary PDMS columns and multiple secondary PDMS columns positioned between the upper and lower PDMS layers. The primary PDMS columns are arranged in a matrix, as are the secondary PDMS columns. A secondary PDMS column is positioned between any two adjacent primary PDMS columns. The top and bottom of each primary PDMS column are fixedly connected to the upper and lower PDMS layers, respectively. The bottom of each secondary PDMS column is fixedly connected to the lower PDMS layer. A gap is left between the top of each secondary PDMS column and the upper PDMS layer. The pore pressure measurement layer, except for the pressure-sensitive area, is made of polydimethylsiloxane. The output leads of the pore pressure measurement layer and the three-electrode layer are both led out from the layered stacked structure and connected to the microprocessor. The microprocessor is equipped with calibration models for pore pressure and flow rate, as well as calibration models for current and concentration. The microprocessor measures the pore pressure through the pore pressure measurement layer and then combines it with the calibration models for pore pressure and flow rate to obtain the flow rate of the liquid. The microprocessor collects the current through the three-electrode layer and then combines it with the calibration models for current and concentration to obtain the concentration of the target ion in the liquid. The microprocessor combines the flow rate of the liquid and the concentration of the target ion in the liquid to calculate the flux of the target ion in the liquid.

2. The flexible thin-film ion concentration and flow sensor according to claim 1, characterized in that: Both the encapsulation layer and the pore pressure measurement layer are provided with multiple vertically penetrating flow channels, and the multiple flow channels on the encapsulation layer and the pore pressure measurement layer are completely overlapping and connected.

3. The flexible thin-film ion concentration and flow sensor according to claim 1, characterized in that: Both the encapsulation layer and the pore pressure measurement layer have lead-out holes near their edges. A metal pad is provided on the top surface of the encapsulation layer at the lead-out hole. The output lead of the pore pressure measurement layer passes through the lead-out hole of the encapsulation layer and is connected to the metal pad. The output lead of the three-electrode layer passes through the lead-out holes of the pore pressure measurement layer and the encapsulation layer in sequence and is connected to the metal pad.

4. The flexible thin-film ion concentration and flow sensor according to claim 1, characterized in that: Both the encapsulation layer and the substrate layer are made of polyimide film.

5. The flexible thin-film ion concentration and flow sensor according to claim 1, characterized in that: The thickness of the upper and lower silver ion layers is 9-11 μm, the thickness of the FEP and PET layers is 7-9 μm, the thickness of the upper and lower PDMS layers is 9-11 μm, the height of the primary PDMS pillar is 70-90 μm, and the height of the secondary PDMS pillar is 30-50 μm.

6. A flexible thin-film ion concentration and flow sensor according to claim 1, characterized in that: The three-electrode layer is located at the bottom of the upper flow channel and includes a working electrode, a reference electrode, and a counter electrode. The working electrode is a Cr / Au electrode, a Cu / Au electrode, or a graphene electrode, and is arranged in a serpentine semi-circular structure. The surface of the working electrode is modified with Prussian blue mediator and an ion-selective film. The reference electrode is an Ag / AgCl electrode coated with polyvinyl butyral. The counter electrode is a gold electrode or a graphene electrode. Output leads are connected to the working electrode, the reference electrode, and the counter electrode.

7. A flexible thin-film ion concentration and flow sensor according to claim 6, characterized in that: The three-electrode layer is located at the bottom of the upper flow channel tank and is equipped with a temperature sensor and a pH electrode probe. Both the temperature sensor and the pH electrode probe are connected to output leads.

8. The method for measuring flexible thin-film ion concentration and flow rate sensor according to claim 1, characterized in that: Specifically, the following steps are included: (1) The microprocessor acquires the pore pressure value P(t) measured by the pore pressure measurement layer in real time. The microprocessor has a built-in calibration model of pore pressure and flow velocity v(t)=K1(P(t)), where K1 is the fitting parameter of pore pressure and flow velocity, and v(t) is the flow velocity. The real-time flow velocity corresponding to the real-time pore pressure value is calculated by the calibration model of pore pressure and flow velocity. (2) The microprocessor calculates the volumetric flow rate Q(t) according to the following formula (1): Q(t)=v(t)S (1; In equation (1), S represents the effective cross-sectional area through which the liquid flows; (3) The microprocessor acquires the peak current i of the target ion measured by the three-electrode layer in real time. p (t), the microprocessor has a built-in calibration model for current and concentration c(t)=K2(i p (t)), K2 is the fitting parameter for current and concentration, and c(t) is the ion concentration. The ion concentration corresponding to the real-time peak current of the target ion is obtained by calculating the calibration model of current and concentration. (4) The microprocessor multiplies the volumetric flow rate by the ion concentration to calculate the flux of the target ion, as shown in the following formula (2): N(t)=c(t)Q(t) (2; In equation (2), N(t) represents the flux of the target ion, which is the molar flow rate through the effective cross section per unit time.

Images