A hydrogel CO gas monitoring device

Abstract

The present invention relates to the field of mine fire prevention, and in particular to a hydrogel CO gas monitoring device, comprising a CO gas sensing module, a conductive hydrogel, a control and transmission module, and a pressure-resistant hydrogel matrix, wherein the control and transmission module comprises a signal conditioning module and a wireless transmission module; the CO gas sensing module is arranged on one side of the pressure-resistant hydrogel matrix, and interdigital electrodes are arranged between the CO gas sensing module and the pressure-resistant hydrogel matrix, and the interdigital electrodes are connected to the control and transmission module through the conductive hydrogel; after the CO gas sensing module absorbs CO gas, the overall resistance of the CO gas sensing module changes, and a signal is generated, and the signal is transmitted to the signal conditioning module via the conductive hydrogel for operational amplification, and the wireless transmission module transmits the amplified signal. The present invention solves the problems that the existing coal mine fire early warning device needs to lay lines and has high maintenance costs, and achieves the purpose of removing the circuit laying and maintenance costs, and has low cost and is easy to use.

Description

Technical Field

[0001] The present invention relates to the field of mine fire prevention, and in particular to a hydrogel CO gas monitoring device for monitoring CO concentration in a goaf, so as to achieve the early warning purpose of preventing spontaneous combustion of coal residue in the goaf. Background Art

[0002] At present, spontaneous combustion of coal in goaf is one of the major disasters in coal mines. Gas combustion and explosion caused by spontaneous combustion of coal are the main reasons for casualties and huge economic losses in coal mines. Mine fires are difficult to detect, develop rapidly, and are difficult to extinguish and rescue. Once a mine fire occurs, if the fire cannot be controlled in time, the scope of the fire will expand rapidly, causing a large number of casualties. When a mine fire occurs, a large amount of spontaneous combustion gas of coal will be generated. The longer the people in distress are in a high-concentration spontaneous combustion gas environment, the lower the probability of survival.

[0003] At present, the coal spontaneous combustion gas monitoring methods include temperature monitoring method, gas monitoring method, smoke monitoring method, visible light image monitoring method, infrared image monitoring method and other mine fire monitoring methods. Temperature monitoring methods include thermocouple temperature measurement method, infrared temperature measurement method and optical fiber distributed temperature measurement method.

[0004] For the above monitoring methods, the advantages and disadvantages of these monitoring methods are mainly:

[0005] Among the temperature monitoring methods, thermocouple temperature measurement and semiconductor temperature measurement have the advantages of high accuracy, strong real-time performance, and the ability to detect early fires in a timely manner, but they have the disadvantages of large sensor usage and heavy maintenance workload. Infrared temperature measurement has the advantages of a wide monitoring range and easy sensor deployment, but obstructions and coal dust between the sensor and the object being measured will affect the monitoring results. Optical fiber distributed temperature measurement has the advantages of being able to monitor multiple points of temperature and requiring less cables, but it has the disadvantages of easy damage to the optical fiber, complex installation, and difficult maintenance.

[0006] The gas monitoring method and the smoke monitoring method have the advantages of a wide monitoring range and easy use and maintenance, but they cannot monitor early fires with low concentrations of characteristic gases and less smoke.

[0007] The visible light image monitoring method has the advantages of wide monitoring range, easy use and maintenance, and low cost. However, interference sources such as tunnel lights, mining lamps, car lights, red clothing, and smoke will affect the monitoring effect, and it cannot monitor early fires without flames and with less smoke.

[0008] The infrared image monitoring method has the advantages of wide monitoring range, easy use and maintenance, but it is costly, and obstructions and coal dust between the infrared camera and the object being measured will affect the monitoring effect. Summary of the invention

[0009] In view of the above-mentioned defects, the present invention provides a technical solution of a hydrogel CO gas monitoring device, which solves the problems of the existing coal mine fire warning device requiring the laying of lines and high maintenance costs, thereby achieving the purpose of eliminating the circuit laying and maintenance costs. The device is low in cost and easy to use. The sensor of the solution only needs to be placed in the area to be monitored and directly adhered to the coal wall to monitor the CO gas.

[0010] The present invention provides the following technical solutions: a hydrogel CO gas monitoring device, comprising a CO gas sensing module for sensing CO gas, a control and transmission module, a conductive hydrogel connecting the CO gas sensing module and the control and transmission module, and a pressure-resistant hydrogel matrix for wrapping the control and transmission module, wherein the control and transmission module comprises a signal conditioning module for amplifying the signal generated by the CO gas sensing module and a wireless transmission module for transmitting the amplified signal; the CO gas sensing module is arranged on one side of the pressure-resistant hydrogel matrix, and interdigital electrodes are arranged between the CO gas sensing module and the pressure-resistant hydrogel matrix, wherein the interdigital electrodes are connected to the control and transmission module through the conductive hydrogel, and the interdigital electrodes and the control and transmission module are respectively connected to a power source; after the CO gas sensing module absorbs CO gas, the overall resistance of the CO gas sensing module changes, and a signal is generated, and the signal is transmitted to the signal conditioning module via the conductive hydrogel for amplification, and the wireless transmission module transmits the amplified signal. The pressure-resistant hydrogel has self-adhesion and high compressive strength, and can protect the CO gas sensing module and the wireless transmission module.

[0011] The signal conditioning module is connected to the interdigital electrodes, and the wireless transmission module is connected to the signal conditioning module. The signal conditioning module and the wireless transmission module are arranged in a protective shell, and the protective shell is wrapped by a pressure-resistant hydrogel matrix. The interdigital electrodes are connected to the control and transmission module through conductive hydrogels, and the conductive hydrogels are arranged in the pressure-resistant hydrogel matrix, and the power supply is arranged in the protective shell. The interdigital electrodes are used to improve the sensitivity and responsiveness of gas monitoring. The conductive hydrogel is arranged in the pressure-resistant hydrogel matrix. The conductive hydrogel itself has excellent conductivity and adhesion. When used, it is directly adhered to the interdigital electrodes, which is convenient and fast. Moreover, the conductive hydrogel has strain and flexibility. It is deformed by external effects, and the resistance value will increase rapidly. After the external effects end, the conductive hydrogel returns to its original state, and the resistance value will also return to its original size. In this way, the surrounding environmental changes and the sensor itself can be monitored by the signal generated by the rapid change of the resistance value. The pressure-resistant hydrogel insulates and separates the wireless transmission module from the CO gas sensing module, and a groove is arranged on one side of the pressure-resistant hydrogel matrix, and the CO gas sensing module is arranged in the groove. In this way, the control and transmission module and the conductive hydrogel can be contained and protected by the pressure-resistant hydrogel to avoid the influence of external impurities.

[0012] The CO gas sensing material of the CO gas sensing module includes MXene material and polyaniline. When preparing the CO gas sensing material, weigh 0.010 g Ti 3 AlC 2 Dissolve in 10 ml of deionized water and mix with ultrasound for 30 min to prepare Ti 3 AlC 2 Then add 200ul aniline monomer and Ti into 30ml 2mol / L HCl solution. 3 AlC 2 The aqueous dispersion was stirred magnetically for 30 minutes, 20 ml of 0.1 mol / L ammonium persulfate hydrochloric acid solution was slowly added, and the stirring reaction was continued for 3 hours. Then 0.005 g of hexadecyl trimethyl ammonium bromide was added and the reaction was continued for 24 hours. The mixture was filtered, washed repeatedly with deionized water and ethanol, and vacuum dried to obtain the CO gas sensing material. HCl was added to polyaniline as a protonic acid. The doping of protonic acid made polyaniline conductive, thereby improving the sensing and electrical conductivity of CO gas. Hexadecyl trimethyl ammonium bromide was added to the solution as a cationic surfactant. Its function was to catalyze the electropolymerization reaction of polyaniline, shift its oxidation potential negatively, reduce membrane degradation, improve membrane stability, and also accelerate the polymerization rate. Finally, the mixture was filtered and washed repeatedly with deionized water and ethanol. The purpose of using deionized water was to wash away the unreacted HCl solution and ammonium persulfate solution, and the purpose of using ethanol was to wash away the unreacted aniline organic solution. When washing, it was first washed with deionized water, and then washed with ethanol. The gas sensing material was obtained after drying.

[0013] The conductive hydrogel is cellulose nanofibers, polydopamine, polyacrylamide and Fe 3+The formation of supramolecular interactions between them. When preparing the conductive hydrogel, first put the NaClO solution into a sealed bottle. Then add 2,2,6,6-tetramethylpiperidin-1-oxyl and NaBr to water and stir to dissolve. Then, disperse the wet wood pulp in the above solution. Finally, under magnetic stirring, measure the prepared NaClO solution with a pipette and add it dropwise to the above reaction system. Then, add NaOH solution dropwise to the reaction system to maintain the pH value of the reaction system at 10 for a long time. When the pH value of the solution does not decrease, the reaction is considered to be complete. Finally, the solution is adjusted to neutral (pH = 7) with HCl, washed with deionized water 4 times, and sonicated with an ultrasonic cell disruptor for 15 minutes to obtain the final cellulose nanofiber solution. Then dilute the prepared cellulose nanofiber solution and put the diluted cellulose nanofiber solution into a beaker. Then add an appropriate amount of NaOH to adjust the pH of the solution to about 10. Dopamine is then dissolved in deionized water and poured into the cellulose nanofiber solution at about 10 °C. Then stir with magnetic force for about 20 minutes until the solution turns brown. Then add acrylamide to the reaction system. Lower the temperature of the ice bath to below 4°C and keep the stirred solution for about 5 minutes until the acrylamide is completely dissolved. Then, add N,N,N',N'-tetramethylethylenediamine to the reaction system. Then dissolve ammonium persulfate in the reaction system. After stirring for another 10 minutes, the solution becomes viscous. Add FeCl 3 Dissolve in deionized water and drop into the above reaction system. Stir for about 10 minutes and remove from the ice bath. Pour the solution into a covered petri dish, seal it with an insulation film, and finally place the petri dish in a 40°C constant temperature water bath for 24 h to obtain a conductive hydrogel. Conductive hydrogel is a conductive hydrogel with conductivity, compression resistance, flexibility, adhesion and strain; the flexibility of the conductive hydrogel can be stretched six times on the original basis and the adhesion wall will not fall off; the strain of the conductive hydrogel combined with the conductivity can realize the monitoring of pulse beating, which plays a role in monitoring the changes in the underground mine environment and the changes in the hydrogel CO gas monitoring device itself under the influence of external factors, and has rapid response capability and good recovery.

[0014] The compressive hydrogel matrix is ​​a polyacrylamide compressive hydrogel with dopamine added, so that the hydrogel has tensile resistance and elasticity, high adhesion strength and long retention time.

[0015] There is a breathable dust-proof membrane outside the CO gas sensing module. It is dust-proof and can avoid the impact of coal dust on gas monitoring.

[0016] The wireless transmission module uses an FM built-in antenna and the transmission protocol is 802.11ac, which is convenient for transmitting wireless signals.

[0017] From the above description, it can be seen that the hydrogel CO gas monitoring device of this scheme embeds the CO gas sensing module in the hydrogel, and sprays a breathable dust-proof film on the surface of the gas sensing material, which has dust resistance and can avoid the influence of coal dust on gas monitoring. By using conductive hydrogel to connect the interdigital electrodes and the control and transmission module, the sensor can transmit the corresponding signal when it is affected by the outside world. By using hydrogel as a substrate to adhere and protect the gas sensing wireless transmission device, the existing coal mine fire warning device needs to lay circuits and has high maintenance costs, and the purpose of removing the cost of circuit laying and maintenance is achieved. It is low-cost and easy to use, which brings convenience to the monitoring of spontaneous combustion gas in underground mines. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a cross-sectional view of a specific embodiment of the present invention.

[0019] Figure 2 It is a structural schematic diagram of a specific implementation mode of the present invention.

[0020] Figure 3 Schematic diagram of the structure of the CO gas sensing module.

[0021] Figure 4 Schematic diagram of the structure of the compressive hydrogel matrix.

[0022] Figure 5 This is a diagram showing the use status of the sensor of the present invention.

[0023] Figure 6 This is a test diagram of the adhesion and mechanical properties of conductive hydrogel.

[0024] Figure 7 Schematic diagram of the wrist connected with conductive hydrogel as strain sensor electrode.

[0025] Figure 8 The resistance / time response diagram of the conductive hydrogel tested as a strain sensor.

[0026] Fig. 9 This is a simulation test diagram of 100ppm CO gas concentration of the hydrogel CO gas monitoring device.

[0027] Fig.10 This is a simulation test diagram of 50ppm CO gas concentration of the hydrogel CO gas monitoring device.

[0028] In the figure, 1 is a CO gas sensing module, 2 is a forked electrode, 3 is a conductive hydrogel, 4 is a pressure-resistant hydrogel matrix, 5 is a protective shell, 6 is a power supply, 7 is a line connector, 8 is a signal conditioning module, 9 is a circuit board, 10 is a wireless transmission module, 11 is a coal wall, 12 is a hydrogel CO gas monitoring device, and 13 is a signal receiver. DETAILED DESCRIPTION

[0029] The following will be combined with the drawings in the specific embodiments of the present invention to clearly and completely describe the technical solutions in the specific embodiments of the present invention. Obviously, the specific embodiment described is only one specific embodiment of the present invention, not all specific embodiments. Based on the specific embodiments of the present invention, all other specific embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0030] As can be seen from the accompanying drawings, the hydrogel CO gas monitoring device of the present invention includes a CO gas sensing module 1 for sensing CO gas, a control and transmission module, and a pressure-resistant hydrogel matrix 4 for wrapping the control and transmission module, wherein the control and transmission module includes a signal conditioning module 8 for performing operational amplification on the signal generated by the CO gas sensing module, and a wireless transmission module 10 for transmitting the signal conditioned by the signal conditioning module; the CO gas sensing module 1 is arranged on one side of the pressure-resistant hydrogel matrix 4, and an interdigital electrode 2 is arranged between the CO gas sensing module 1 and the pressure-resistant hydrogel matrix 4, a groove is arranged on one side of the pressure-resistant hydrogel matrix 4, the CO gas sensing module 1 is arranged in the groove, the interdigital electrode 2 is connected to the control and transmission module, and the interdigital electrode 2 and the control and transmission module are respectively connected to a power supply 6; after the CO gas sensing module 1 absorbs CO gas, the overall resistance of the CO gas sensing module 1 changes, and a signal is generated, and the signal is transmitted to the signal conditioning module 8 via the conductive hydrogel 3 for operational amplification, and the wireless transmission module 10 transmits the amplified signal. The compression-resistant hydrogel matrix 4 is a polyacrylamide compression-resistant hydrogel with dopamine added. The hydrogel is mainly formed by mixing water and oil with polyacrylamide hydrogel with dopamine added. The compression-resistant hydrogel matrix has self-adhesion and strong compression strength, and the hydrogel has a long retention time. There is a breathable anti-dust film outside the CO gas sensing module. The wireless transmission module 10 uses an FM built-in antenna, and the transmission protocol is 802.11ac.

[0031] The signal conditioning module 8 is connected to the interdigital electrode 2, and the wireless transmission module 10 is connected to the signal conditioning module 8. The signal conditioning module 8 and the wireless transmission module 10 are arranged in a protective shell 5, and the protective shell 5 is wrapped by a pressure-resistant hydrogel matrix 4. The interdigital electrode 2 is connected to the control and transmission module through a metal wire 3, and the metal wire is arranged in the pressure-resistant hydrogel matrix 4. The power supply 6 is arranged in the protective shell 5. The CO gas sensing module 1 is a CO gas sensing material comprising MXene material and polyaniline.

[0032] When preparing CO gas sensing materials, weigh 0.01gTi 3 AlC 2 Dissolved in 10 ml of deionized water and ultrasonically mixed for 30 min, and prepared into Ti3 AlC 2 Then add 200ul aniline monomer and Ti into 30ml 2mol / L HCl solution. 3 AlC 2 The aqueous dispersion was stirred magnetically for 30 minutes, 20 ml of 0.1 mol / L ammonium persulfate hydrochloric acid solution was slowly added, the stirring reaction was continued for 3 hours, and then 0.005 g of hexadecyl trimethyl ammonium bromide was added to continue the reaction for 24 hours; the mixture was filtered, washed repeatedly with deionized water and ethanol, and dried to obtain the CO gas sensing material. The polyaniline used in the preparation of the gas sensing material has an adsorption effect on CO gas, and its own conductivity changes after adsorbing CO gas. After adding the MXene material, its conductivity is increased, and the conductivity change after adsorbing CO gas is expanded to generate a resistive gas sensing material. The gas sensing material also has high hydrophobicity, which can prevent coal dust coverage from affecting gas absorption and sensing. The gas sensing material has good sensitivity and repeatability to low-concentration gases and can work normally at room temperature.

[0033] The conductive hydrogel is prepared by conformal coating of cellulose nanofiber network and supramolecular interaction between cellulose nanofiber (CNF), polydopamine (PDA), iron and polyacrylamide (PAM). Cellulose nanofibers are prepared by oxidizing hardwood pulp with 2,2,6,6-tetramethylpiperidin-1-oxyl. First, an appropriate amount of dopamine is added to the prepared cellulose nanofiber aqueous solution with a pH value of 10 under vigorous stirring at 10°C for about 20 minutes until the solution changes from a transparent colorless state to a brownish yellow color. In this process, dopamine is oxidized and polymerized into polydopamine, and hydrogen bonds are formed between the catechol groups of polydopamine and the carboxyl groups of cellulose nanofibers. Secondly, under magnetic stirring at 4°C, an appropriate amount of acrylamide, N, N, N', N'-tetramethylethylenediamine and an excess of ammonium persulfate are added to the above reaction solution for about 15 minutes to initiate the polymerization of acrylamide. After polymerization, the carboxyl functional groups of cellulose nanofibers form hydrogen bonds with the amide groups of polyacrylamide and the catechol groups of polydopamine. 3 The solution was added to the above solution and stirred vigorously at 4 °C for about 10 min to evenly disperse the Fe 3+ . Dispersed Fe 3+ The ions were chelated with the catechol groups of polydopamine and the carboxyl groups of cellulose nanofibers. Finally, the reaction system was placed in a 40 °C water bath for 24 h to obtain the conductive hydrogel. It is worth noting that cellulose nanofibers, as a degradable reinforcing nanocomponent, not only enhanced the mechanical properties of the conductive hydrogel, but also 3+ The weak chelation of 3+Oxidation. Since the catechol groups of PDA have strong adhesion to the surfaces of inorganic and organic substances by forming hydrogen bonds or covalent bonds, the self-adhesive ability of polydopamine is given by its catechol groups. 3+ CNF-Fe 3+ Coordinates and tris-orthocatechol-Fe 3+ The coordination between CNF, PDA and PAM, as well as the hydrogen bonding between CNF, PDA and PAM, the prepared hydrogels have excellent mechanical properties. In addition, the tunable conductive channels of conductive hydrogels endow them with highly sensitive sensing properties for ions.

[0034] The specific preparation process of the conductive hydrogel is as follows: first, put 50 ml of 10 wt% NaClO solution into a sealed bottle for later use; add 30 mg 2,2,6,6-tetramethylpiperidine-1-oxyl and 100 mg NaBr into water, stir to dissolve, and then add 10 mg wet wood pulp for dispersion; under magnetic stirring, measure the prepared NaClO solution with a pipette and add it dropwise to the reaction system, then, add 0.5 M NaOH solution dropwise to the reaction system to maintain the pH value of the reaction system at 10 for a long time, and when the pH value of the solution does not decrease, the reaction is completed, and finally, adjust the solution of the reaction system to neutral with HCl, wash with deionized water 4 times, and ultrasonically treat with an ultrasonic cell disruptor for 15 minutes to obtain a cellulose nanofiber solution.

[0035] The prepared cellulose nanofiber solution was diluted to 0.5wt%, 20ml of the diluted cellulose nanofiber solution was placed in a beaker, and then NaOH was added to adjust the pH of the solution to 10, and then 0.012g of dopamine was dissolved in deionized water and poured into the cellulose nanofiber solution at about 10°C, and then magnetically stirred for about 20 minutes until the color of the solution turned brown-yellow, and then 5.5g of acrylamide was added to the reaction system, and the temperature of the ice bath was lowered to below 4°C. The stirred solution was kept for about 5 minutes until the acrylamide was completely dissolved, and then 40ul of N,N,N',N'-tetramethylethylenediamine was added to the reaction system, and then 0.6g of ammonium persulfate was dissolved in the reaction system, and the solution was stirred for 10min, and 0.016g of FeCl 3 Dissolve in deionized water, add dropwise to the above reaction system, stir for about 10 minutes, take out the ice bath, pour the solution into a covered Petri dish, seal it with an insulation film, and finally place the Petri dish in a constant temperature water bath at 40°C for 24 hours to obtain a conductive hydrogel.

[0036] Figure 6This is a test diagram of the stretchability of the conductive hydrogel. It can be seen from the figure that the conductive hydrogel can be stretched to 600% of its original length and will not fall off due to the self-adhesion between the hydrogel and the two fingers. The adhesion of the conductive hydrogel is attributed to polydopamine, because its polyphenol groups can form strong and reversible coordination bonds, such as hydrogen bonds, π-π stacking and metal coordination bonds, and can firmly adhere to the surface of the material through chelation. In this way, the conductive hydrogel will not fall off when connected to the interdigital electrodes and the control and transmission module, nor will it fall off due to external pressure. It has strong compressive resistance and strong adhesion.

[0037] like Figure 7 As shown in the paper, the conductive hydrogel-based strain sensor adheres directly to the skin and can monitor the bending and stretching of the human body, such as the movement of the wrist, without the need for additional auxiliary equipment. The hydrogel adheres stably to the body, and it can repeatedly monitor the movement even when undergoing large deformations.

[0038] The application of the hydrogel CO gas monitoring device obtained by the above preparation method will use the sensor obtained by the above preparation method, encapsulate the circuit and perform pressure strain test and CO gas leakage simulation test. Figure 8 The resistance value / time response diagram of the conductive hydrogel as a strain sensor. The response value change of the conductive hydrogel in the hydrogel CO gas monitoring device during the pressure test was recorded. The response value is the relative change in resistance ΔR / R 0 , where R 0 and R are the original resistance and resistance of the sensor after being compressed, respectively. The highest response value in the test results is 32%, which has high responsiveness and can timely monitor the external pressure changes of the hydrogel CO gas monitoring device. Fig. 9 and Fig.10 The waveform diagram transmitted by the hydrogel CO gas monitoring device at 100ppm and 50ppm CO gas concentration can be displayed in real time on the signal receiver 13, and then the signal waveform diagram is processed by the signal receiver 13 to display the specific concentration of CO gas in real time, so as to achieve the purpose of real-time early warning.

[0039] The application of household carbon monoxide gas monitoring, the application of the hydrogel CO gas monitoring device obtained by the above preparation method, the sensor obtained by the above preparation method, the encapsulated circuit and set in the field of household carbon monoxide monitoring.

[0040] The hydrogel CO gas monitoring device can be applied to CO gas monitoring and alarm in various situations. The hydrogel CO gas monitoring device is flexible and reliable, can be attached to any area where CO gas may be generated, can monitor CO gas leakage caused by household coal stoves in real time, and is protected by a pressure-resistant hydrogel matrix on the outside, and has good environmental adaptability.

[0041] The application of carbon monoxide gas monitoring in coal mines, the application of the hydrogel CO gas monitoring device obtained by the above preparation method, the sensor obtained by the above preparation method is used, the circuit is packaged and a network is set up to realize signal transmission between multiple sensors, and it is applied to the field of carbon monoxide gas monitoring in coal mines.

[0042] When in use, it is only necessary to place the hydrogel CO gas monitoring device 12 in the area that needs to be monitored, such as directly adhering to the coal wall 11 to monitor the gas. The monitoring signal can be transmitted wirelessly to the signal receiver 13, which is a well-known displayable receiver; it is convenient for staff to view. When the hydrogel CO gas monitoring device is subjected to external influences, such as falling off or changes in the underground environment, the conductive hydrogel will respond, and the resistance value will change dramatically with the change of the conductive hydrogel, which is much larger than the resistance response generated when the CO gas sensing material senses the gas. This is conducive to distinguishing the two, and is more conducive to the monitoring of CO gas and environmental changes underground.

[0043] Although specific embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the specific embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the appended claims and their equivalents.

Claims

1. A hydrogel CO gas monitoring device, characterized in that: It includes a CO gas sensing module for sensing CO gas, a conductive hydrogel, a control and transmission module, and a pressure-resistant hydrogel matrix for wrapping the control and transmission module. The control and transmission module includes a signal conditioning module for performing operational amplification on the signal generated by the CO gas sensing module, and a wireless transmission module for transmitting the operational amplified signal; The CO gas sensing module is arranged on one side of the pressure-resistant hydrogel matrix, and an interdigital electrode is arranged between the CO gas sensing module and the pressure-resistant hydrogel matrix, the interdigital electrode is connected to the control and transmission module through the conductive hydrogel, and the interdigital electrode and the control and transmission module are respectively connected to the power supply; after the CO gas sensing module absorbs CO gas, the overall resistance of the CO gas sensing module changes, and a signal is generated, and the signal is transmitted to the signal conditioning module through the conductive hydrogel for operational amplification, and the wireless transmission module transmits the amplified signal; The CO gas sensing material used in the CO gas sensing module includes MXene material and polyaniline; When preparing the CO gas sensing material, 0.010g Ti3AlC2 was weighed and dissolved in 10ml deionized water and ultrasonically mixed for 30min to prepare a Ti3AlC2 aqueous dispersion. Then, 200ul aniline monomer and the Ti3AlC2 aqueous dispersion were added to 30ml of 2mol / L HCl solution and magnetically stirred for reaction for 30min. Then, 20ml of 0.1mol / L ammonium persulfate hydrochloric acid solution was slowly added and stirred for reaction for 3h. Then, 0.005g hexadecyltrimethylammonium bromide was added and the reaction was continued for 24h. The CO gas sensing material was filtered, repeatedly washed with deionized water and ethanol, and vacuum dried to obtain the CO gas sensing material.

2. The hydrogel CO gas monitoring device according to claim 1, characterized in that: The signal conditioning module is connected to the interdigital electrodes, the wireless transmission module is connected to the signal conditioning module, the wireless transmission module uses an FM built-in antenna, and the transmission protocol is 802.11ac.

3. The hydrogel CO gas monitoring device according to claim 1, characterized in that: The signal conditioning module and the wireless transmission module are arranged in a protective shell, the protective shell is wrapped by a pressure-resistant hydrogel matrix, the interdigitated electrodes are connected to the control and transmission module through conductive hydrogel, the conductive hydrogel is wrapped by flexible insulating glue and arranged in the pressure-resistant hydrogel matrix, and the power supply is arranged in the protective shell.

4. The hydrogel CO gas monitoring device according to claim 1, characterized in that: A groove is arranged on one side of the pressure-resistant hydrogel matrix, and the CO gas sensing module is arranged in the groove.

5. The hydrogel CO gas monitoring device according to claim 1, characterized in that: The compression-resistant hydrogel matrix is ​​a polyacrylamide compression-resistant hydrogel added with dopamine.

6. The hydrogel CO gas monitoring device according to claim 1, characterized in that: A breathable and dust-proof membrane is arranged on the side of the CO gas sensing module away from the pressure-resistant hydrogel group.

7. The hydrogel CO gas monitoring device according to claim 1, characterized in that: The conductive hydrogel is composed of cellulose nanofiber solution, polydopamine, polyacrylamide and Fe 3+ The prepared conductive hydrogel is a conductive hydrogel with conductivity, compression resistance, flexibility, adhesion and strain.

8. The hydrogel CO gas monitoring device according to claim 7, characterized in that: The preparation of the cellulose nanofiber solution comprises the following steps: first, putting 50 ml of a 10 wt% NaClO solution into a sealed bottle for later use; adding 30 mg of 2,2,6,6-tetramethylpiperidin-1-oxyl and 100 mg of NaBr into water, stirring to dissolve, and then adding 10 mg of wet wood pulp for dispersion; under magnetic stirring, dripping the prepared NaClO solution measured by a pipette, and then continuously dripping a 0.5 M NaOH solution to maintain the pH value at 10 for a long time, and when the pH value of the solution does not decrease, the reaction is completed; finally, adjusting the solution to neutrality with HCl, washing with deionized water for 4 times, and ultrasonically treating with an ultrasonic cell disruptor for 15 minutes to obtain a cellulose nanofiber solution.

9. The hydrogel CO gas monitoring device according to claim 7, characterized in that: Preparation of the conductive hydrogel: first, dilute the prepared cellulose nanofiber solution to 0.5wt%, put 20ml of the diluted cellulose nanofiber solution into a beaker, then add NaOH, adjust the pH of the solution to 10, then dissolve 0.012g of dopamine in deionized water, pour it into the cellulose nanofiber solution, stir it with a magnetic force at a temperature of 10°C for 20 minutes until the color of the solution changes to brown-yellow, then add 5.5g of acrylamide, reduce the temperature of the ice bath to below 4°C, keep the stirred solution for 5 minutes until the acrylamide is completely dissolved, then add 40ul of N,N,N',N'-tetramethylethylenediamine, then dissolve 0.6g of ammonium persulfate, stir the solution for 10min, dissolve 0.016g of FeCl3 in deionized water, add it dropwise to the above solution, stir for 10 minutes, take out the ice bath, pour the solution into a covered culture dish, seal it with an insulation film, and finally place the culture dish in a constant temperature water bath at 40°C for 24h to obtain a conductive hydrogel.

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