Oxygen-humidity bimodal sensor and preparation method thereof

Abstract

The invention discloses an oxygen-humidity bimodal sensor and a preparation method thereof.The oxygen-humidity bimodal sensor comprises a hydrogel block body capable of controlling and adjusting the water content, a positive electrode and a negative electrode, and the hydrogel block body at least contains two kinds of ions with different hydrophilicity; the positive electrode and the negative electrode are arranged on the same side or two sides of the hydrogel block body, and the negative electrode comprises a conductive body with air permeability. The embodiment of the invention can measure various information, is good in stability and strong in anti-interference capability, and can be widely applied to the technical field of sensing.

Description

Technical Field

[0001] The present invention relates to the field of sensor technology, and in particular to an oxygen-humidity dual-mode sensor and a preparation method thereof. Background Art

[0002] Appropriate oxygen and humidity concentrations are necessary conditions for the survival of humans and even most organisms. Real-time and continuous perception of them is of great significance in the fields of environmental protection and health safety. In addition, oxygen and humidity monitoring also play an important role in the medical field. Usually, an independent sensor element can only measure one stimulus signal due to its fixed material structure and properties. In order to understand the surrounding signals more comprehensively at a lower cost, multimodal sensors that can sense multiple signals are in urgent need of development. So far, the development of single oxygen or humidity sensors has gradually matured, while integrated oxygen-humidity dual-mode sensors are rarely mentioned.

[0003] With the continuous development of artificial intelligence and Internet of Things technologies, sensors need to be integrated into smart wearable electronic devices that can be directly worn or integrated into clothing, so it is quite necessary to directly develop flexible wearable sensors. Traditionally, the development of multimodal sensors relies on the integration of various sensor elements or functional materials, which will lead to an increase in the size and power consumption of the final wearable system, which is not conducive to practical application. Moreover, the accurate identification between the various stimulus signals of multimodal sensors depends on the assistance of algorithm systems and artificial intelligence, which will lead to an increase in system complexity. Therefore, it is urgent to develop an integrated crosstalk-free multimodal sensor based on a single functional material. Smart materials can controllably change their own properties through external stimuli, so exploring new smart materials as sensing functional components is expected to achieve highly selective perception of different signals under different material states.

[0004] Currently, self-powered sensors are made by coupling sensors with energy harvesting equipment (triboelectric nanogenerators, solar cells, thermal batteries), so that the devices can continue to operate by collecting ambient energy. However, due to the instability of external driving energy (light, mechanical energy, temperature difference, etc.), the output signals of such devices are also unstable, and the sensing performance is also disturbed. Summary of the invention

[0005] In view of this, in order to solve one of the above problems, an object of an embodiment of the present invention is to provide an oxygen-humidity dual-mode sensor and a preparation method thereof, which can measure multiple information, has good stability and strong anti-interference ability.

[0006] On the one hand, an embodiment of the present invention provides an oxygen-humidity dual-modal sensor, comprising a hydrogel block with controllable water content, a positive electrode and a negative electrode, wherein the hydrogel block contains at least two ions with different hydrophilicities, the positive electrode and the negative electrode are arranged on the same side or both sides of the hydrogel block, and the negative electrode includes a gas-permeable conductor.

[0007] Optionally, the negative electrode comprises carbon cloth, and the positive electrode comprises a metal electrode.

[0008] Optionally, the metal electrode includes any one of a zinc electrode, an aluminum electrode, a magnesium electrode or an iron electrode.

[0009] Optionally, the ratio of the surface area of ​​the negative electrode to the surface area of ​​the hydrogel block on the side where the negative electrode is located is in a range of 15% to 40%.

[0010] Optionally, the surface area of ​​the positive electrode is equal to the surface area of ​​the negative electrode.

[0011] Optionally, the hydrogel mass is formed by dispersing a polymer network in water.

[0012] Optionally, the material of the polymer network includes acrylamide, methylenebisacrylamide and ammonium persulfate.

[0013] Optionally, the material of the polymer network includes polyacrylic acid and polyvinyl alcohol.

[0014] On the other hand, an embodiment of the present invention provides a method for preparing an oxygen-humidity dual-mode sensor, comprising:

[0015] Providing a hydrogel, a positive electrode and a negative electrode; the hydrogel block contains at least two ions with different hydrophilicities, and the negative electrode includes a conductor with air permeability;

[0016] cutting the hydrogel into hydrogel blocks of a preset size;

[0017] The positive electrode and the negative electrode are attached to the same side or both sides of the hydrogel block.

[0018] Optionally, the hydrogel is prepared by the following method:

[0019] Add a preset mass of acrylamide, methylenebisacrylamide and ammonium persulfate into a preset volume of deionized water and stir until completely dissolved;

[0020] An accelerator is added to obtain a clear solution, which is then heated at a preset temperature for a preset time to polymerize to obtain a hydrogel.

[0021] Implementation of the embodiments of the present invention includes the following beneficial effects: the oxygen-humidity dual-mode sensor of the embodiment includes a hydrogel block with controllable water content, a positive electrode and a negative electrode, the hydrogel block contains at least two ions with different hydrophilicities, and the ions with different hydrophilics enable the hydrogel block to reversibly switch between a water-deficient state and a water-rich state, the positive electrode and the negative electrode are arranged on the same side or both sides of the hydrogel block, the negative electrode includes a gas-permeable conductor, oxygen and water undergo redox reactions at the negative electrode to achieve oxygen and humidity measurement, and different sensing functions are achieved by changing the state of the material itself, and high-selective detection of the two signals can be achieved without the assistance of an algorithm, and the oxygen-humidity dual-mode sensor based on the primary cell structure converts chemical energy into electrical energy to provide its own energy during the redox process, does not require external drive, has good stability, has no crosstalk in the measurement of oxygen and humidity, and has strong anti-interference ability. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 is a structural schematic diagram of an oxygen-humidity dual-mode sensor provided by an embodiment of the present invention;

[0023] Figure 2 is a schematic diagram of regulating the water content of different hydrogels provided in an embodiment of the present invention;

[0024] Figure 3 It is a structural schematic diagram of an oxygen-humidity dual-mode sensor provided by an embodiment of the present invention and a self-powered verification result diagram;

[0025] Figure 4 is a schematic diagram of an oxygen sensor working mechanism provided by an embodiment of the present invention;

[0026] Figure 5 is a schematic diagram of the results of characterizing the oxygen sensing performance provided by an embodiment of the present invention;

[0027] Figure 6 is a schematic diagram of a humidity sensing working mechanism provided by an embodiment of the present invention;

[0028] Figure 7 is a schematic diagram of a result of characterizing humidity sensing performance provided by an embodiment of the present invention;

[0029] Figure 8 is a schematic diagram of test performance results of an oxygen-humidity dual-mode sensor provided by an embodiment of the present invention;

[0030] Fig. 9 is a schematic diagram of application verification results of an oxygen-humidity dual-mode sensor provided by an embodiment of the present invention;

[0031] Fig.10is a schematic diagram of application verification results of another oxygen-humidity dual-mode sensor provided by an embodiment of the present invention;

[0032] Fig.11 It is a schematic flow chart of the steps of a method for preparing an oxygen-humidity dual-mode sensor provided by an embodiment of the present invention;

[0033] Fig.12 The present invention provides a flow chart of the preparation of a hydrogel. DETAILED DESCRIPTION

[0034] The present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. The step numbers in the following embodiments are only provided for the convenience of explanation and description, and the order between the steps is not limited in any way. The execution order of each step in the embodiment can be adaptively adjusted according to the understanding of those skilled in the art.

[0035] The self-powered and flexible gas-humidity dual-modal sensor is a wearable device that does not require an external power supply. It can convert oxygen and humidity signals into electrical signal changes and can be used in environmental protection, health and safety, and medical fields.

[0036] See also Figure 1 , Figure 1 (a) shows the top view of the oxygen-humidity dual-mode sensor. Figure 1 (a) shows a side view of an oxygen-humidity dual-mode sensor. An embodiment of the present invention provides an oxygen-humidity dual-mode sensor, comprising a hydrogel block (1-1) with controllable water content, a positive electrode (1-3) and a negative electrode (1-2), wherein the hydrogel block (1-1) contains at least two ions with different hydrophilicities, the positive electrode (1-3) and the negative electrode (1-2) are arranged on the same side or both sides of the hydrogel block (1-1), and the negative electrode (1-2) comprises a gas-permeable conductor.

[0037] It should be noted that the hydrogel block contains at least two ions with different hydrophilicities, and the difference in hydrophilicity between the two ions is within a certain range.

[0038] In a specific embodiment, see Figure 2 The intelligent behavior of controllably changing its own water content is endowed by introducing two specific ions (Li + and Zn 2+ ), named ZL-PAM. Compared with the original PAM hydrogel (named P-PAM), low hydrophilic Zn 2+ The PAM hydrogel (named Z-PAM) and highly hydrophilic Li +Compared with the introduced PAM hydrogel (named L-PAM), ZL-PAM can reversibly switch between water-deficient and water-rich states. However, L-PAM is difficult to dehydrate to a water-deficient state, and P-PAM and Z-PAM are difficult to absorb water from the surrounding environment after dehydration and return to the previous water-rich state.

[0039] See also Figure 3 The oxygen-humidity dual-mode sensor uses zinc sheet as the positive electrode, carbon cloth as the negative electrode, and smart PAM hydrogel as a flexible solid electrolyte. Due to the differences in chemical potential and properties, different redox reactions will occur after the electrodes at both ends of the sensor are connected and output current, allowing the device to operate with self-power. At the negative electrode, the oxygen reduction reaction (ORR) will occur, and both oxygen and water will act as reactants that affect the device current, realizing oxygen and humidity sensing, but will be subject to mutual interference. Since the smart hydrogel prepared by the present invention can be reversibly switched between water-rich and water-deficient states, oxygen and humidity will act as limiting reactants in different states of the hydrogel to affect the output of the device, thereby realizing non-cross-linked dual-mode oxygen and humidity sensing on a single device.

[0040] See also Figure 4 The oxygen sensing working mechanism of the self-powered and flexible oxygen-humidity dual-mode sensor designed in the embodiment of the present invention in a water-rich state relies on oxygen as the only limiting reactant, which plays a decisive role in the ORR reaction rate. At this time, the water in the hydrogel far exceeds the number of water molecules required for ORR. Water as an excess reactant will not affect the output signal of the device, achieving humidity-insensitive oxygen sensing. Figure 5 , Figure 5 The sensing performance of the oxygen sensor based on water-rich ZL-PAM is shown. It can be seen that the device can monitor an ultra-wide range of oxygen with high sensitivity but shows a weak response to high humidity stimulation. It has a low oxygen monitoring limit, good repeatability and selectivity, which is conducive to the accurate detection of oxygen in practice.

[0041] See also Figure 6 The self-powered and flexible oxygen-humidity dual-mode sensor designed in the embodiment of the present invention has a humidity sensing mechanism in a water-deficient state. The humidity as a limiting reactant not only directly participates in the ORR, but also acts as a catalyst to promote the adsorption of oxygen, material diffusion and charge transfer processes, resulting in changes in the output signal. At this time, the device's response to oxygen is greatly suppressed, achieving highly selective humidity sensing. Figure 7 , Figure 7The sensing performance of the humidity sensor based on water-deficient ZL-PAM is shown. It can be seen that the device can detect humidity in an ultra-wide range, and the sensitivity is further improved in the high humidity range; for the same humidity stimulus, the device shows a basically consistent response, indicating its good repeatability; when the device's response to different stimulus signals is tested, it is found that it has good resistance to environmental interference, which is conducive to the accurate detection of humidity in practice.

[0042] The self-powered and flexible sensor designed in the embodiment of the present invention has reversibly switchable dual-mode sensing capabilities of oxygen and humidity. Figure 8 As shown in (a), after the water-rich ZL-PAM undergoes a water loss-water absorption cycle, the oxygen sensing performance of the device is similar to that of the original one. Figure 8 As shown in (b), after the water-deficient ZL-PAM undergoes a water absorption-dehydration cycle, the humidity sensing performance of the device is similar to that of the original one. This indicates that the sensing ability of the device can be reversibly switched by regulating the water content of the functional material.

[0043] The device exhibits high oxygen (4170.5% / %) and humidity (380.2 / %RH) sensitivity, wide detection range and ultra-low detection limit (0.4ppm oxygen and 1000ppm RH) in both water-rich and water-deficient states. This crosstalk-free dual-modal sensing capability is attributed to the fact that oxygen or humidity, respectively, acts as the key limiting reactant and catalyst to affect the electrode reaction rate of the device in different states.

[0044] Optionally, the negative electrode comprises carbon cloth, and the positive electrode comprises a metal electrode.

[0045] Carbon cloth refers to cloth made of carbon materials, such as carbon fiber, graphene, etc. Carbon cloth has good conductivity and air permeability; metal can provide electrons, and using carbon cloth as the negative electrode and using metal as the positive electrode can improve the performance of the sensor.

[0046] Optionally, the metal electrode includes any one of a zinc electrode, an aluminum electrode, a magnesium electrode or an iron electrode.

[0047] The metal electrode is determined according to the actual application, including but not limited to any one of a zinc electrode, an aluminum electrode, a magnesium electrode or an iron electrode. The metal electrode may also be an alloy.

[0048] Optionally, the ratio of the surface area of ​​the negative electrode to the surface area of ​​the hydrogel block on the side where the negative electrode is located is in a range of 15% to 40%.

[0049] Optionally, the surface area of ​​the positive electrode is equal to the surface area of ​​the negative electrode.

[0050] The surface area of ​​the negative electrode and the side area of ​​the hydrogel block are controlled within a suitable range, and the surface area of ​​the positive electrode is equal to the surface area of ​​the negative electrode, which can improve the sensitivity of the detection.

[0051] Optionally, the hydrogel mass is formed by dispersing a polymer network in water.

[0052] Optionally, the material of the polymer network includes acrylamide, methylenebisacrylamide and ammonium persulfate.

[0053] Optionally, the material of the polymer network includes polyacrylic acid and polyvinyl alcohol.

[0054] It should be noted that the polymer network is a complex material system composed of cross-linked polymer chains. The specific characteristics are as follows: elasticity, the polymer network material can deform when subjected to external force, and can return to its original shape after the external force is removed; strain hardening, when subjected to large stress, the elastic modulus of the polymer network material will increase, showing a stronger ability to resist deformation; ductility, the polymer network material can withstand large deformation without breaking during stretching; heat resistance, due to the three-dimensional network structure formed by chemical bonds between polymer chains, polymer network materials usually have good heat resistance; solvent resistance, due to its insoluble and infusible characteristics, polymer network materials show good stability in solvents; dimensional stability, once the cross-linked structure is formed, the shape and size of the polymer network usually do not change.

[0055] The material of the polymer network is determined according to practical applications, and includes but is not limited to acrylamide, methylenebisacrylamide and ammonium persulfate, or polyacrylic acid and polyvinyl alcohol.

[0056] The embodiment of the present invention conceptually verifies the feasibility of the practical application of a self-powered and flexible oxygen-humidity dual-modal sensor based on water-rich ZL-PAM. Fig. 9 As shown in (ac), the device placed in a sealed bottle together with the oxygen absorber can reflect the oxygen consumption in the bottle in real time, quickly and accurately. In order to demonstrate the capabilities of wireless and remote oxygen monitoring, a wireless hypoxia alarm system was developed by combining the sensor with wireless communication technology. The system can sense and process oxygen concentration information, transmit it to a mobile phone terminal through a self-programming application, and respond to its changes. Fig. 9 As shown in (de), when the device is moved from the air into an oxygen-deficient bottle containing an oxygen absorbent, its current drops rapidly and falls below the threshold set by the system, sounding an alarm. When the device is moved back into the air, the alarm stops. Therefore, the system shows great potential for safe exploration in unknown environments. In addition, the device can be applied in the medical field. Fig. 9(fg), when the device and the heating belt are close to the skin, the output signal will change, realizing the monitoring of TcPO2. Based on this, the device can distinguish between squatting and standing postures.

[0057] Oxygen sensing test: The sensor current is recorded by an electrochemical workstation. It is placed in a homemade sealed container, and nitrogen and target gas are repeatedly passed in and out of the container through a pipe for dynamic testing. The type and concentration of the gas in the container are controlled by the DGL-III gas-liquid distribution system, which can mix inorganic gases (such as H2S, O2, NO, NH3 and CO2) in standard cylinders or organic gases volatilized at high temperatures by pure organic liquids (ethanol, isopropanol and acetone) with nitrogen at different flow ratios. In order to achieve gas detection at different humidity levels, a wet gas path is added by the bubble method, and the flow rate is additionally controlled by a digital mass flow controller (MFC). The humidity of the final test container is controlled by adjusting the flow ratio of the dry gas mixed gas path flowing out of the DGL-III gas distribution system and the wet gas path flowing out of the MFC, and the total gas flow rate is set to 500sccm.

[0058] The embodiment of the present invention conceptually verifies the feasibility of the practical application of a self-powered and flexible oxygen-humidity dual-mode sensor based on water-deficient ZL-PAM. Fig.10 As shown in (ad), by attaching the device to the inside of the mask, breathing monitoring can be performed to identify breathing frequency and different breathing states, including normal, slow, fast breathing and apnea. This is a convenient and effective means of diagnosing and treating sleep apnea syndrome (SAS). In addition, sensitive humidity sensors are an effective means of realizing non-contact HMI, which can avoid the spread of bacteria / viruses caused by direct contact. Fig.10 As shown in (eh), when a finger approaches the device, the current of the device rises due to the increase in humidity, and the different distances between the finger and the device can be identified from the response level. Based on this, the present invention has developed a non-contact human-machine interface based on a 2×2 humidity sensor array, which can identify different approaches of fingers, showing the great potential of our sensor array in non-contact gesture recognition. In addition, the present invention successfully applies this non-contact human-machine interface based on humidity sensors to the control of elevators, replacing the traditional contact controller.

[0059] Humidity sensing test: The sensor current is also recorded by the electrochemical workstation. Saturated solutions of different salts are prepared in sealed glass bottles, and different special humidity environments are obtained above the solutions. During the test, the sensor is suspended above the saturated solution in the glass bottle, and the relative humidity around the sensor is changed by quickly transferring the sensor to sealed glass bottles with different relative humidity.

[0060] Oxygen sensing application: To verify the feasibility of the device to monitor ambient oxygen, a sealed bottle was used to simulate an actual enclosed space, and a commercial iron powder oxygen absorber was used to simulate oxygen-consuming organisms. During the test, the sensor was placed in a sealed bottle and its current changes were recorded. In order to monitor TcPO2, the device was first attached to one end of a commercial breathable heating tape, and the heating tape was powered on and left to wait for the current to stabilize. During the test, the other side of the heating tape was placed close to the skin surface and its current changes were recorded.

[0061] Humidity sensing application: For breathing detection, the device is attached to the inner side of a commercial mask or directly attached to the lower end of the nose. During the test, volunteers wear masks and breathe in different states, and the current changes are recorded in real time. In order to verify the feasibility of non-contact human-computer interaction applications, fingers are placed close to the device or device array to record the current changes.

[0062] A wireless hypoxia, apnea and non-contact elevator control system was developed by connecting the device with a self-made circuit system. The system can sense and process the stimulus signal, and transmit it wirelessly to the mobile terminal through the Bluetooth module and display it on the self-programmed application. When the program detects that the stimulus signal changes below the threshold, an alarm will occur on the mobile interface.

[0063] The sensor realizes convenient and timely monitoring of ambient oxygen, TcPO2, respiration and skin humidity. Combined with wireless communication technology, a wireless hypoxia alarm system, apnea alarm system, non-contact human-computer interaction interface and non-contact elevator control system are designed, which can sensitively identify and feedback hypoxic environment, apnea and finger proximity, and has broad application prospects in human health, safety protection and non-contact human-computer interaction.

[0064] Implementation of the embodiments of the present invention includes the following beneficial effects: the oxygen-humidity dual-mode sensor of the embodiment includes a hydrogel block with controllable water content, a positive electrode and a negative electrode, the hydrogel block contains at least two ions with different hydrophilicities, and the ions with different hydrophilics enable the hydrogel block to reversibly switch between a water-deficient state and a water-rich state, the positive electrode and the negative electrode are arranged on the same side or both sides of the hydrogel block, the negative electrode includes a gas-permeable conductor, oxygen and water undergo redox reactions at the negative electrode to achieve oxygen and humidity measurement, and different sensing functions are achieved by changing the state of the material itself, and high-selective detection of the two signals can be achieved without the assistance of an algorithm, and the oxygen-humidity dual-mode sensor based on the primary cell structure converts chemical energy into electrical energy to provide its own energy during the redox process, does not require external drive, has good stability, has no crosstalk in the measurement of oxygen and humidity, and has strong anti-interference ability.

[0065] See also Fig.11 , an embodiment of the present invention provides a method for preparing an oxygen-humidity dual-mode sensor, comprising:

[0066] S100, providing a hydrogel, a positive electrode and a negative electrode; the hydrogel block contains at least two ions with different hydrophilicities, and the negative electrode includes a gas-permeable conductor;

[0067] S200, cutting the hydrogel into hydrogel blocks of preset sizes;

[0068] S300, attaching the positive electrode and the negative electrode to the same side or both sides of the hydrogel block.

[0069] In a specific embodiment, it is composed of a smart PAM hydrogel that can controllably change its own water content and zinc sheets and carbon cloth electrodes attached to both ends. The preparation process is as follows: the prepared smart PAM hydrogel that can controllably change its own water content is cut into blocks of 10*20*3mm, and the zinc sheets and carbon cloth are cut into 3*10mm strips and attached to both ends of the hydrogel to form a self-powered dual-mode sensor. By connecting the three devices in series, the diode can be lit, indicating its self-powered capability.

[0070] Optionally, the hydrogel is prepared by the following method:

[0071] S010, adding a preset mass of acrylamide, methylenebisacrylamide and ammonium persulfate into a preset volume of deionized water, and stirring until completely dissolved;

[0072] S020, adding an accelerator to obtain a clear solution, heating at a preset temperature for a preset time to polymerize, and obtaining a hydrogel.

[0073] In a specific embodiment, see Fig.12 First, pure PAM hydrogel was synthesized by a simple one-pot method. 6.22g acrylamide (AM), 3.6mg N,N'-methylenebisacrylamide (MBA) and 37.40mg ammonium persulfate (APS) were added to 40mL deionized water and stirred at 600rpm for 30min until completely dissolved. Then, 20μL N,N,N',N'-tetramethyleneethylenediamine accelerator was added to the solution, and the obtained clear solution was poured into a culture dish and heated at 70℃ for 5h to polymerize to obtain PAM hydrogel. After cooling, the PAM hydrogel was placed in a mixed solution of 1M ZnSO4 and 3M LiBr for 2h to finally obtain ZL-PAM hydrogel.

[0074] The characterization of the hydrogel's ability to regulate its own water content was performed by placing the sample in a high humidity and dry environment, measuring and recording the sample mass at intervals and calculating the water loss ratio. During the water loss process, the sample was placed in a constant temperature and humidity chamber at 25°C and 40% RH. During the water absorption process, the sample's environment was modified to 25°C and 98% RH.

[0075] The implementation of the embodiments of the present invention includes the following beneficial effects: the preparation method of the oxygen-humidity dual-mode sensor is highly feasible and convenient for mass production.

[0076] The above is a specific description of the preferred implementation of the present invention, but the invention is not limited to the embodiments. Those skilled in the art may make various equivalent modifications or substitutions without violating the spirit of the present invention. These equivalent modifications or substitutions are all included in the scope defined by the claims of this application.

Claims

1. An oxygen-humidity dual-mode sensor, characterized in that: It comprises a hydrogel block with controllable water content, a positive electrode and a negative electrode. The hydrogel block contains at least two ions with different hydrophilicities. The positive electrode and the negative electrode are arranged on the same side or both sides of the hydrogel block. The negative electrode comprises a gas-permeable conductor.

2. The oxygen-humidity dual-mode sensor according to claim 1, characterized in that: The negative electrode includes a carbon cloth, and the positive electrode includes a metal electrode.

3. The oxygen-humidity dual-mode sensor according to claim 1, characterized in that: The metal electrode includes any one of a zinc electrode, an aluminum electrode, a magnesium electrode or an iron electrode.

4. The oxygen-humidity dual-mode sensor according to claim 1, characterized in that: The ratio of the surface area of ​​the negative electrode to the surface area of ​​the hydrogel block on the side where the negative electrode is located is in the range of 15% to 40%.

5. The oxygen-humidity dual-mode sensor according to claim 1, characterized in that: The surface area of ​​the positive electrode is equal to the surface area of ​​the negative electrode.

6. The oxygen-humidity dual-mode sensor according to claim 1, characterized in that: The hydrogel mass is formed by dispersing a polymer network in water.

7. The oxygen-humidity dual-mode sensor according to claim 6, characterized in that: The materials of the polymer network include acrylamide, methylenebisacrylamide and ammonium persulfate.

8. The oxygen-humidity dual-mode sensor according to claim 6, characterized in that: The materials of the polymer network include polyacrylic acid and polyvinyl alcohol.

9. A method for preparing an oxygen-humidity dual-mode sensor, characterized in that: include: Providing a hydrogel, a positive electrode and a negative electrode; the hydrogel block contains at least two ions with different hydrophilicities, and the negative electrode includes a conductor with air permeability; cutting the hydrogel into hydrogel blocks of a preset size; The positive electrode and the negative electrode are attached to the same side or both sides of the hydrogel block.

10. The preparation method according to claim 9, characterized in that: The hydrogel is prepared by the following method: Add a preset mass of acrylamide, methylenebisacrylamide and ammonium persulfate into a preset volume of deionized water and stir until completely dissolved; An accelerator is added to obtain a clear solution, which is then heated at a preset temperature for a preset time to polymerize to obtain a hydrogel.

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