Geofluoroether detection sensor and method based on platinum-doped MoS2 interdigital electrode

Abstract

The invention relates to the technical field of gas detection, and discloses a platinum-doped MoS2 interdigital electrode-based desflurane detection sensor, which comprises an interdigital electrode, a power supply and an ampere meter, wherein the sensing area of the platinum-doped MoS2 interdigital electrode is provided with a gas sensitive material layer composed of platinum-doped MoS2, the platinum-doped MoS2 interdigital electrode comprises a sensing electrode connected with an ampere meter, and the sensing electrode and the ampere meter jointly measure the resistance of the gas sensitive material layer. The change degree of the resistance value of the gas-sensitive material layer is in positive correlation with the concentration of the desflurane gas flowing on the surface of the gas-sensitive material layer; the invention further discloses a detection method of the desflurane detection sensor based on the platinum-doped MoS2 interdigital electrode. Real-time monitoring of the concentration of the desflurane in the air is achieved, after the platinum-doped MoS2 material in the sensor adsorbs the desflurane, the resistance of the material can rapidly respond in a short time, the sensitivity is high, automatic desorption can be achieved, and repeated use is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of gas detection, and particularly to a desflurane detection sensor and method based on a platinum-doped MoS2 interdigital electrode. Background Art

[0002] Desflurane is a new type of volatile halogenated inhalational anesthetic. Compared with other anesthetics, desflurane has the advantages of lower blood solubility and less pulmonary circulation uptake. Therefore, desflurane has been widely used in clinical surgeries.

[0003] However, the imperfect administration technology and the defects of the anesthetic delivery system often lead to the leakage and pollution of desflurane in the operating room. It is reported that long-term exposure to desflurane may cause adverse reactions such as cognitive impairment and neurodegenerative diseases. Therefore, when performing operations related to desflurane, it is necessary to monitor the exposure of desflurane.

[0004] Currently, the commonly used methods for monitoring anesthetic gas concentration are generally infrared measurement method, gas chromatography method, mass spectrometry method, etc. The detection devices made based on these methods often have the disadvantages of high cost, large volume, and low measurement accuracy, resulting in difficulty in accurately monitoring the exposure of desflurane in the operating room.

[0005] Therefore, there is a need for a detection sensor and monitoring method that can more accurately and real-time monitor the concentration of desflurane Summary of the Invention

[0006] The purpose of the present invention is to provide a desflurane detection sensor and method based on a platinum-doped MoS2 interdigital electrode to solve the technical problems of high cost and complex monitoring method of the existing desflurane concentration monitoring equipment.

[0007] To solve the above technical problems, the present invention specifically provides the following technical solutions: The present invention provides a desflurane detection sensor based on a platinum-doped MoS2 interdigital electrode, including a platinum-doped MoS2 interdigital electrode, an external power supply, and an ammeter. The platinum-doped MoS2 interdigital electrode, the power supply, and the ammeter are connected in series as a whole to form a resistive desflurane sensor, and the resistive desflurane sensor is used to detect the desflurane concentration; Among them, a gas-sensitive material layer composed of platinum-doped MoS2 is provided in the sensing area of the platinum-doped MoS2 interdigital electrode. The platinum-doped MoS2 interdigital electrode includes a sensing electrode connected to the ammeter. The sensing electrode and the ammeter jointly measure the resistance of the gas-sensitive material layer. After the gas-sensitive material layer adsorbs desflurane, its inherent resistance value changes, and the degree of change in the resistance value of the gas-sensitive material layer is positively correlated with the concentration of desflurane gas flowing on its surface.

[0008] As a preferred embodiment of the present invention, it further includes a heating electrode, the heating electrode is disposed between the sensing electrode of the platinum-doped MoS2 interdigital electrode and the gas-sensitive material layer, the heating electrodes are respectively located on both sides of the gas-sensitive material layer, and the heating electrode can be connected to an external power supply to heat the gas-sensitive material layer.

[0009] As a preferred embodiment of the present invention, the method for preparing the platinum-doped MoS2 interdigital electrode includes the following steps: Add platinum-doped MoS2 gas-sensitive material powder into ethylene glycol, use magnetic stirring, and remove the bubbles in the liquid through a numerical control ultrasonic instrument until the powder is evenly dispersed to obtain a slurry. Soak the interdigital electrode in distilled water and anhydrous ethanol in sequence, and clean it with a numerical control ultrasonic instrument. Inject the slurry into a microelectronic printer, and use the microelectronic printer to coat the slurry on the surface of the coating area of the interdigital electrode to form the gas-sensitive material layer, and attach the heating electrode to the interdigital electrode. Under an insulated state, place the interdigital electrode in a vacuum drying oven, use a vacuum pump to evacuate the vacuum drying oven, heat and dry it, then rinse it with deionized water and anhydrous ethanol in sequence, and dry it again to obtain the platinum-doped MoS2 interdigital electrode. For every 10 mg of platinum-doped MoS2 gas-sensitive material, 10 - 30 mL of ethylene glycol is used correspondingly. The rotation speed of the magnetic stirring is 500 r / s - 600 r / s, the stirring time is 5 - 7 h, the rotation speed of the numerical control ultrasonic instrument is 70 - 80 Hz, and the time is 0.5 - 1 h. The drying temperature of the vacuum drying oven is 60°C - 80°C, and the drying time is 5 h - 6 h.

[0010] As a preferred embodiment of the present invention, the method for preparing the platinum-doped MoS2 gas-sensitive material includes the following steps: Fully grind molybdenum trioxide and sulfur powder and mix them with a transport agent to obtain a mixture. Place the mixture on one side of a vacuum-sealed quartz tube, and place a growth substrate on the other side of the quartz tube, and perform a vacuum treatment on the quartz tube. Put the quartz tube into a two-zone tube furnace for two-zone heating. Place the end with the mixture in the high-temperature zone, and place the growth substrate in the low-temperature zone at room temperature. After the heating time ends, cool to room temperature and take out the sample on the growth substrate. Fully grind the sample, add chloroplatinic acid and the ground MoS₂ into an oxidant, perform magnetic stirring, and obtain a mixed solution after full reaction. After the stirring is completed, centrifuge the mixed solution, dry the mixed solution to obtain a powder, and wash the powder to obtain the platinum-doped MoS₂ gas-sensitive material.

[0011] As a preferred embodiment of the present invention, the mass ratio of molybdenum trioxide, sulfur powder, and the transport agent is 1:2:5 to 1:2:10; The transport agent is any one of I₂ and Br₂; The growth substrate is any one of a glass sheet, sapphire, and mica sheet; The oxidant is any one of ascorbic acid, sodium citrate, and sodium borohydride; In the two-temperature zone heating, the high-temperature zone of the two-temperature zone tube furnace is 500°C to 700°C, the holding time is 1 h to 2 h, and the low-temperature zone is at room temperature; The time of the magnetic stirring is 1 to 3 h, and the rotation speed is 500 to 600 r / min; The dosage of the ground MoS₂ is 10 mg, the dosage of chloroplatinic acid is 5 mL to 15 mL, and the dosage of the oxidant is 15 mL to 25 mL; The solvent for the washing is anhydrous ethanol and deionized water, and the number of times is 3 - 5 times.

[0012] The present invention also discloses a detection method for a desflurane detection sensor based on a platinum-doped MoS₂ interdigital electrode, including the following steps: S100. Calibrate the concentration relationship between the concentration of desflurane in the air and the resistance value of the sensor; S200. Place the sensor in the environment to be detected, calculate the resistance value of the sensor through the ammeter, and obtain the desflurane concentration value in the environment to be detected according to the concentration relationship.

[0013] As a preferred embodiment of the present invention, in S100, the calibration method for the correlation between the concentration of desflurane in the air and the resistance value of the gas-sensitive material layer includes the following steps: S110. Construct a detection gas path system for desflurane gas. The detection gas path system for desflurane gas includes a desflurane gas cylinder, a high-purity air cylinder, a gas mixer, and the sensor. The sensor is placed in a box body; Connect the air outlets of the desflurane gas cylinder and the high-purity air cylinder to the gas mixer, keep the box body in a closed state, the gas mixer is communicated with the box body, and the box body has an exhaust pipeline with a controllable passage; S120. Check the airtightness of the gas path, adjust the gas distributor to flush the gas path with desflurane gas, and then use a vacuum pump to evacuate the sealed cavity in the box to vacuum from the exhaust pipeline, and cycle three times to ensure that there is no impurity gas. S130. Introduce high-purity air into the sealed cavity. After waiting for the resistance value of the ammeter to stabilize, record the resistance value R0 at this time. S140. Use the gas distributor to configure mixed gases of desflurane and air with different concentrations and introduce them into the sealed cavity, record the resistance values R of different concentrations, and obtain the relationship between the change in resistance value and the concentration of desflurane in the mixed gas.

[0014] As a preferred embodiment of the present invention, the following step is further included: heating the gas-sensitive material layer to 55 °C through the heating electrode.

[0015] As a preferred embodiment of the present invention, taking the resistance peak value of the sensor as Y and the concentration of desflurane in the air as X, the relationship between the resistance peak value of the sensor and the concentration of desflurane in the air is: Y = 0.583X + 0.071, R = 0.998; Wherein, the unit of the concentration is ppm.

[0016] The present invention has the following beneficial effects compared with the prior art: In the present invention, a gas-sensitive resistor composed of a platinum-doped MoS2 material is connected in series with an ammeter and a power supply. When the electrode containing this material is placed in the environment to be detected, it can absorb desflurane in the environment to be detected, and its inherent conductivity will change. The ammeter value of the interdigitated electrode resistance detected in real time changes, so as to realize the real-time monitoring of the desflurane concentration in the environment. Moreover, the conductivity of this gas-sensitive resistor can respond quickly in seconds and is sensitive. In the gas-sensitive resistor type sensor of the present invention, the detected resistance peak value is positively correlated with the concentration of desflurane flowing on its surface. The resistance element can not only adsorb desflurane, but also automatically desorb and quickly release gas when the concentration of desflurane in the air decreases, and its inherent conductivity will quickly recover. By detecting the change in the resistance value of this interdigitated electrode, the dynamic balance monitoring of the desflurane concentration in the air can be realized, and it is easy to operate. In the present invention, a heating electrode is provided on the gas-sensitive resistor of the platinum-doped MoS2 material, which can realize the dynamic balance of the reaction during the detection process and control the desorption efficiency through temperature control, so as to realize the repeated use of the gas-sensitive interdigitated electrode in the sensor. A desflurane detection method provided by the present invention continuously introduces the gas to be detected into the detection cavity of a desflurane detection sensor containing platinum-doped MoS2 interdigital electrodes through a pump body. The sensor can automatically adsorb desflurane in the gas to be detected for detection and reflect the detection result to an ammeter. The detected concentration is linearly related to the detected value, and it is convenient to use. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only exemplary, and for those of ordinary skill in the art, without creative efforts, other implementation drawings can also be obtained according to the provided drawings.

[0018] Figure 1 It is a schematic connection structure diagram of a desflurane detection sensor based on platinum-doped MoS2 interdigital electrodes provided by the present invention; Figure 2 Provided by the present invention Figure 1 It is a schematic structure diagram of the interdigital electrodes in the illustrated embodiment; Figure 3 It is a partial schematic structure diagram of a desflurane detection sensor based on platinum-doped MoS2 interdigital electrodes in Embodiment 1 provided by the present invention; Figure 4 It is a schematic structure diagram of a desflurane detection sensor based on platinum-doped MoS2 interdigital electrodes in Embodiment 1 provided by the present invention; Figure 5 It is a schematic diagram of the detection gas path system for desflurane gas in Embodiment 1 provided by the present invention; Figure 6 It is a gas sensitivity test result diagram of the sensor for standard gases with different concentrations provided by the present invention; Figure 7 It is a linear relationship diagram of the standard gas concentration and the response value based on fitting provided by the present invention; Figure 8 It is a gas sensitivity test result diagram of the sensor for standard gases at different temperatures provided by the present invention; Figure 9 It is a flow chart of the preparation method of the interdigital electrodes of platinum-doped MoS2 provided by the present invention; Figure 10 It is a schematic flow diagram of the preparation method of platinum-doped MoS2 gas-sensitive material provided by the present invention; Figure 11 It is an adsorption configuration diagram of Pt-MoS2 for oxygen in Detection Example 1 provided by the present invention; Figure 12 It is an adsorption configuration diagram of Pt-MoS2 for nitrogen in Detection Example 1 provided by the present invention; Figure 13 This invention provides the adsorption configuration diagram of Pt-MoS2 shown in Detection Example 1 for C3H2OF6; Figure 14 This invention provides the band gap diagram of the energy band of Pt-MoS2 shown in Detection Example 1; Figure 15 This invention provides the band gap change diagram of the energy band of Pt-MoS2 for adsorbed N2 shown in Detection Example 1; Figure 16 This invention provides the band gap change diagram of the energy band of Pt-MoS2 for adsorbed oxygen shown in Detection Example 1; Figure 17 This invention provides the band gap change diagram of the energy band of Pt-MoS2 for adsorbed C3H2OF6 shown in Detection Example 1.

[0019] The labels in the figure respectively represent the following: 1 - Desflurane gas cylinder; 2 - High-purity air cylinder; 3 - Gas mixer; 4 - Interdigitated electrode; 401 - Substrate; 402 - Sensing electrode; 403 - Gas-sensitive material layer; 404 - Heating electrode; 5 - Ammeter; 6 - Power supply; 7 - Wire group; 8 - Box body; 9 - Sealing plate; 10 - Inlet pipe; 11 - Outlet pipe. Detailed implementation mode

[0020] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0021] As Figure 1 and Figure 2 shown, this invention provides a desflurane detection sensor based on a platinum-doped MoS2 interdigitated electrode, including an interdigitated electrode 4, a power supply 6, and an ammeter 5. The platinum-doped MoS2 interdigitated electrode 4, the power supply 6, and the ammeter 5 are connected in series as a whole to form a resistive desflurane sensor.

[0022] The interdigital electrode 4 includes a dielectric layer located on a substrate 401. Above the dielectric layer, there are a sheet-shaped carbon nanotube electrode, a sensing electrode 402, and a heating electrode 404. At one end of the substrate 401, one end of the carbon nanotube electrode is connected to the sensing electrode 402. At the other end of the substrate 401, a plurality of carbon nanotube electrodes are arranged in an interdigital electrode shape to form an attachment area for the platinum-doped MoS2 material. The attachment area of the platinum-doped MoS2 material is a gas-sensitive material layer 403, and the gas-sensitive material layer 403 is arranged to contact the gas to be measured.

[0023] The power supply 6 is connected to the ammeter 5. At the same time, one end of the sensing electrode 402 is connected to the power supply 6, and the other end is connected to the ammeter 5. The sensing electrode 402 and the ammeter 5 jointly measure the resistance of the gas-sensitive material layer 403.

[0024] The working principle of the desflurane detection sensor based on the platinum-doped MoS2 interdigital electrode is as follows: After the gas-sensitive material layer 403 can adsorb desflurane, its inherent resistance value changes, and the value of the ammeter 5 changes. The platinum-doped MoS2 material has a high response sensitivity and a fast speed. At the same time, when the concentration of desflurane continues to decrease, the platinum-doped MoS2 material can also desorb desflurane. After desorption, the resistance value of the gas-sensitive material layer 403 can be reflected in the ammeter 5 in real time, so as to realize the real-time monitoring of desflurane without human intervention and can be used repeatedly.

[0025] This desflurane detection sensor is a gas sensor and can detect whether the air contains desflurane. The usage method of this desflurane detection sensor is as follows: Keep the sensor power supply 6 stable, place the platinum-doped MoS2 interdigital electrode 4 in the environment to be detected, and observe the index of the ammeter 5. The change in the value of the ammeter 5 indicates that the environment to be detected contains desflurane.

[0026] This desflurane detection sensor can be directly applied to environments such as operating rooms that require desflurane anesthetic gas. Through actual use, it can be known that the degree of change in the resistance value of the gas-sensitive material layer 403 is positively correlated with the concentration of desflurane gas flowing on its surface. In order to obtain the specific relationship between the concentration of desflurane gas in the air and the value of the ammeter 5, the present invention provides a detection device, including a box body 8 and the above-mentioned interdigital electrode 4, power supply 6, ammeter 5, and wire group 7 arranged in the box body 8. The upper part of the box body 8 is open.

[0027] This desflurane detection sensor is a gas sensor for detecting the concentration of desflurane in the air. The following provides a method for detecting the concentration of desflurane of a desflurane detection sensor based on a platinum-doped MoS2 interdigital electrode, including the following steps: S100. Calibrate the concentration relationship between the concentration of desflurane in the air and the resistance value of the gas-sensitive material layer 403; S200. Place the sensor in the environment to be detected, calculate the resistance value of the sensor through the ammeter 5, and obtain the desflurane concentration value in the environment to be detected based on the concentration relationship.

[0028] In the present invention, the resistance of the gas-sensitive material layer 403 on the sensor is positively correlated with the desflurane concentration in the air. At the same time, in a stable current, the value shown by the ammeter 5 is also linearly correlated with the resistance. Therefore, the index value of the ammeter 5 is linearly correlated with the desflurane concentration in the air. After actually detecting this correlation relationship and obtaining this correlation relationship through a formula, real-time monitoring can be achieved.

[0029] It can be seen that in the present invention, by connecting a gas-sensitive resistor composed of a platinum-doped MoS2 material in series with an ammeter and a power supply, when the electrode containing this material is placed in the environment to be detected, without manual operation, the gas-sensitive material in the sensor can automatically absorb desflurane in the environment to be detected, and its inherent conductivity will change. The value of the ammeter for real-time detecting the resistance of the interdigital electrodes changes, thereby realizing the real-time monitoring of the desflurane concentration in the environment.

[0030] Furthermore, the following provides a calibration method for the correlation relationship between the concentration of desflurane in the air and the resistance value of the gas-sensitive material layer 403, including the following steps: S110. Construct a detection gas path system for desflurane gas. The detection gas path system for desflurane gas includes a desflurane gas cylinder 1, a high-purity air cylinder 2, a gas mixer 3, and a sensor. The sensor is placed in a box body 8; Connect the outlets of the desflurane gas cylinder 1 and the high-purity air cylinder 2 to the gas mixer 3, keep the box body 8 in a closed state, the gas mixer 3 is connected to the box body 8, and the box body 8 has an exhaust pipeline with a controllable passage; S120. Check the airtightness of the gas path, adjust the gas mixer 3 to flush the gas path with desflurane gas, and then use a vacuum pump to evacuate the closed cavity in the box body 8 to vacuum from the exhaust pipeline, and cycle three times to ensure no impurity gas; S130. Introduce high-purity air into the closed cavity. After waiting for the resistance value of the ammeter 5 to stabilize, record the resistance value R0 at this time; S140. Use the gas mixer 3 to configure mixed gases of desflurane and air with different concentrations and introduce them into the closed cavity, record the resistance values R at different concentrations, and obtain the relationship between the change in the resistance value and the concentration of desflurane in the mixed gas.

[0031] Furthermore, the sensitivity of the sensor is related to temperature. In the present invention, a heating device is used to control the resistivity change degree and desorption time of the sensor, that is, a heating electrode 404 is provided on the interdigital electrode 4. The heating electrode 404 is arranged between the sensing electrode of the interdigital electrode 4 and the gas-sensitive material layer 403. The heating electrodes 404 are respectively located on both sides of the gas-sensitive material layer 403. The heating electrode 404 can be connected to an external power supply to control the temperature of the interdigital electrode 4. The gas-sensitive material layer 403 is heated by the heating electrode 404, and the most sensitive temperature of the sensor is obtained through the resistivity change degree.

[0032] The detection method of the sensor is verified through the following examples: ① Device selection: This embodiment provides a sensor, which has the same function as the above-mentioned sensor. Specifically, as Figures 3 to 4 shown, this sensor includes the above-mentioned platinum-doped MoS2 interdigital electrode 4, power supply 6, ammeter 5, wire group 7. An air inlet pipe 10 and an air outlet pipe 11 are respectively arranged on both sides of the box body 8. A sealing plate 9 is arranged above the box body 8. Except for the communication position of the air inlet pipe 10 and the air outlet pipe 11, the entire box body 8 and the sealing plate 9 form a sealed chamber.

[0033] The power supply 6 and the ammeter 5 are connected in series through the wire group 7. The wire group 7 can be separately connected to the heating electrode 404 to change the temperature through the heating electrode 404.

[0034] ② Construction Figure 5 of the desflurane gas detection gas path system: It includes a desflurane gas cylinder 1, a high-purity air cylinder 2, a gas mixer 3, and a sensor.

[0035] ③ Operation: Calibrate the concentration relationship between the desflurane concentration in the air and the resistance value of the gas-sensitive material layer 403: 1. Connect the air outlets of the desflurane gas cylinder 1 and the high-purity air cylinder 2 to the gas mixer 3. Keep the sealing plate 9 in a sealed state. The gas mixer 3 is connected to the box body 8 through the air inlet pipe 10; 2. Check the airtightness of the gas path. Regulate the gas mixer 3 to flush the gas path with desflurane gas. Then use a vacuum pump to evacuate the sealed cavity in the box body 8 to vacuum from the exhaust pipeline, and circulate three times to ensure no impurity gas; 3. Introduce high-purity air into the sealed cavity. After waiting for the resistance value of the ammeter 5 to stabilize, record the resistance value R0 at this time; 4. Use the gas mixer 3 to configure mixed gases of desflurane and air with different concentrations and introduce them into the sealed cavity until the resistance value stabilizes. Record the resistance values R at different concentrations and obtain the relationship between the resistance value change and the desflurane concentration in the mixed gas.

[0036] Record the resistance change of the interdigital electrode 4 at different concentrations: The resistance change rate data of Example 1 are as follows (temperature is 55 °C): The reaction speed of the sensor at different concentrations, i.e., the resistance peak value, is shown in Figure 6 the figure below.

[0037] Using Figure 7 the linear relationship obtained by fitting the curve to measure the measurement results of other concentration mixed gases is shown in Table 1. It can be seen that the errors of the above sensors are all within 5%, meeting the actual application requirements.

[0038] Table 1 Concentration (μL / L) Measured concentration (μL / L) Error (%) 1 1.05 5.0 3 3.08 2.6 5 4.86 -2.8 15 15.56 3.7 40 40.94 2.1 70 68.13 -2.2 120 118.94 -0.9 Multiple embodiments are set. The difference is that the heating temperature of the heating electrode 404 is different.

[0039] Comparing the resistance change rates of the sensor at different temperatures, the characterization results are shown in Figure 8 .

[0040] The specific data are shown in Table 2: Table 2 Temperature / °C ΔR% 25 7.698 35 11.253 45 17.892 55 29.163 65 22.095 75 19.257 As can be seen from Table 3, when the temperature is 55 °C, the response parameter is the highest at this time.

[0041] By changing the heating temperature of the heating electrode in Example 1, the resistance change rates of the sensor at different temperatures are calculated. The resistance change rate values at different temperatures are shown in Table 3: Table 3 Temperature / °C Rate of change / % 25 7.698 35 11.253 45 17.892 55 29.163 65 22.095 75 19.257 From the results of Table 3, it can be seen that when the temperature reaches 55 °C, the resistance change rate of the sensor is the highest, reaching 29.163%. That is, 55 °C is the optimal working temperature for testing the desflurane detection sensor of the platinum-doped MoS2 interdigital electrode in Example 1.

[0042] Comparing the response parameters of the interdigital electrode to 10 ppm desflurane at different temperatures, the specific response is shown in Figure 16 , and the time from the response peak to the time when the response value is 10% of the response peak is calculated as the desorption time.

[0043] Table 5 shows the desorption times of the interdigital electrode 4 at different temperatures. It can be seen from the table that the higher the temperature, the faster the desorption time. However, considering the influence of the resistance change rate, the optimal working temperature of this resistance sensor is 55 °C.

[0044] Table 4 Temperature / °C Peak time / s 10% Peak time / s Desorption time / s 25 57.32 150.84 93.52 35 61.58 139.23 77.65 45 63.77 127.63 63.86 55 68.13 116.07 47.94 65 74.44 119.43 44.99 75 78.42 106.54 28.12 The electric heating function can achieve the dynamic balance of the reaction during the detection process and control the desorption efficiency (for example, increasing the heating temperature after the ventilation is completed to achieve rapid desorption), thereby enabling the repeated use of the gas-sensitive interdigital electrodes in the sensor.

[0045] Configuring the interdigital electrodes as sensors for detection is a method for evaluating performance. The results of this method are in Figure 6 and Figure 7 , as can be seen from the figure, the sensor of the present invention has the advantages of rapid response and high sensitivity. In Figure 6 , the response time of the resistance is in seconds, and in the desflurane environment at different concentrations, the difference in the resistance peak value of the sensor is large, which is convenient for judgment and easy to distinguish.

[0046] Figure 7 is the linear relationship between the fitted standard gas concentration and the response value at the optimal temperature. The response value is the peak value of the resistance of the gas-sensitive material displayed on the electrochemical workstation 5. Through the corresponding relationship, the data displayed on the electrochemical workstation can be associated with desflurane, realizing the direct reading of the desflurane concentration data.

[0047] Since the resistance peak value is obtained by measuring with the ammeter 5, when the power supply 6 is stable and the temperature of the heating electrode 404 is controlled at 55 degrees Celsius, the concentration of desflurane in the air and the resistance peak value of the interdigital electrode 4 show a linear relationship. This linear relationship is: taking the resistance peak value of the sensor as Y and the concentration of desflurane in the air as X, the relationship between the resistance peak value of the sensor and the concentration of desflurane in the air is: Y = 0.583X + 0.071, R = 0.998; the concentration range is 2 - 100 ppm.

[0048] It can be seen that this sensor can detect desflurane in the concentration range of 2 - 100 ppm, with sensitive reaction, short response time, high sensitivity, and a linear correlation between desflurane in the gas and the resistance change, which is easy to read the concentration of desflurane. After the concentration of desflurane gas drops, the sensor can be automatically desorbed and reused without intervention, with a simple structure and convenient operation; at the same time, by heating the sensor, the dynamic balance of the reaction during the detection process can be achieved, and the desorption efficiency can be controlled (for example, increasing the heating temperature after the ventilation is completed to achieve rapid desorption), thereby realizing the repeated use of the gas-sensitive interdigital electrodes in the sensor.

[0049] As Figure 9 shown, the present invention further provides a preparation method for the above-mentioned platinum-doped MoS2 interdigital electrodes, including the following steps: Adding platinum-doped MoS2 gas-sensitive material powder into ethylene glycol, using magnetic stirring, and removing the bubbles in the liquid through a numerical control ultrasonic instrument until the powder is evenly dispersed to prepare a slurry; The interdigital electrodes were successively immersed in distilled water and absolute ethanol and cleaned using a numerically controlled ultrasonic instrument; The slurry was injected into a microelectronic printer, and the slurry was applied to the surface of the coating area of the interdigital electrodes by the microelectronic printer to form a gas-sensitive material layer; In an insulated state, the interdigital electrodes were placed in a vacuum drying oven, and the vacuum drying oven was evacuated using a vacuum pump. After heating and drying, they were rinsed successively with deionized water and absolute ethanol and dried again to obtain platinum-doped MoS2 interdigital electrodes.

[0050] Preferably, 10 - 30 mL of ethylene glycol was used for every 10 mg of platinum-doped MoS2 gas-sensitive material.

[0051] Preferably, the rotation speed of the magnetic stirrer was 500 r / s - 600 r / s, the stirring time was 5 - 7 h, the rotation speed of the numerically controlled ultrasonic instrument was 70 - 80 Hz, and the time was 0.5 - 1 h.

[0052] Preferably, the drying temperature of the vacuum drying oven was 60 °C - 80 °C, and the drying time was 5 h - 6 h.

[0053] Specifically, the steps for preparing the electrodes used in the above sensor are as follows: S21. Add platinum-doped MoS2 powder and 20 mL of ethylene glycol into a test tube; S22. To uniformly disperse the platinum-doped MoS2 in the solution, use a magnetic stirrer to stir the test tube for 6 hours with the rotation speed set at 600 r / min. Subsequently, use a numerically controlled ultrasonic instrument to vibrate for a period of time to break the internal bubbles in the solution for 1 hour; S23. Immerse the original interdigital electrodes successively in distilled water and absolute ethanol and clean them 3 times with the numerically controlled ultrasonic instrument for 30 minutes each time to ensure that the original interdigital electrodes are absolutely clean; S24. After dispersing the platinum-doped MoS2 powder in the solution to form a slurry, inject it into a microelectronic printer, and apply the slurry to the surface of the coating area of the original interdigital electrodes to form a gas-sensitive material layer 403; S25. Under the condition of ensuring insulation, place the original interdigital electrodes in a vacuum drying oven, evacuate the vacuum drying oven using a vacuum pump, and then start heating to 70 °C for drying for 6 h; S26. Rinse the original interdigital electrodes after applying the slurry and the gas-sensitive material layer 403 successively with deionized water and absolute ethanol and dry them.

[0054] The preparation of this platinum-doped MoS2 interdigital electrode 4 uses an existing interdigital electrode. The difference is that this platinum-doped MoS2 interdigital electrode is covered with a platinum-doped MoS2 material, and this platinum-doped MoS2 can be applied to the sensor after being processed.

[0055] Such as Figure 10As shown, the preparation method of the platinum-doped MoS2 gas-sensitive material is as follows: Molybdenum trioxide and sulfur powder are thoroughly ground and then mixed with a transport agent to obtain a mixture. The mixture is placed on one side of a vacuum-sealed quartz tube, and a growth substrate is placed on the other side of the quartz tube. The quartz tube is evacuated. The quartz tube is placed in a two-zone tube furnace for two-zone heating. The end with the mixture is placed in the high-temperature zone, and the growth substrate is placed in the low-temperature zone at room temperature. After the heating time ends, it is cooled to room temperature, and the sample on the growth substrate is taken out. The sample is thoroughly ground. Chloroplatinic acid and the ground MoS2 are added to an oxidant, and magnetic stirring is carried out. After sufficient reaction, a mixed solution is obtained. After the stirring is completed, the mixed solution is centrifuged and separated. The mixed solution is dried to obtain a powder, and the powder is washed to obtain the platinum-doped MoS2 gas-sensitive material.

[0056] Preferably, the mass ratio of molybdenum trioxide, sulfur powder, and transport agent is 1:2:5 to 1:2:10.

[0057] Preferably, the transport agent is any one of I2 and Br2.

[0058] Preferably, the growth substrate is any one of a glass sheet, sapphire, and mica sheet.

[0059] Preferably, the oxidant is any one of ascorbic acid, sodium citrate, and sodium borohydride.

[0060] Preferably, in the two-zone heating, the high-temperature zone of the two-zone tube furnace is 500°C to 700°C, the holding time is 1 h to 2 h, and the low-temperature zone is at room temperature.

[0061] Preferably, the time of magnetic stirring is 1 to 3 h, and the rotation speed is 50 to 600 r / min.

[0062] Preferably, the amount of ground MoS2 used is 10 mg, the amount of chloroplatinic acid used is 5 mL to 15 mL, and the amount of oxidant used is 15 mL to 25 mL.

[0063] Preferably, the cleaning solvent is anhydrous ethanol and deionized water, and the number of times is 3 - 5 times.

[0064] Specifically, the preparation method of the MoS2 gas-sensitive material used in the above-mentioned platinum-doped MoS2 interdigital electrode 4 is as follows: S11. Molybdenum trioxide and sulfur powder are thoroughly ground and then mixed with iodine. The ratio of molybdenum trioxide, sulfur powder, and iodine is 1:2:5. The mixture is placed on one side of a vacuum-sealed quartz tube, and a growth interdigital electrode is placed on the other side of the quartz tube. The quartz tube is evacuated. S12. Place the quartz tube into a two-temperature-zone tubular furnace. Heat the high-temperature zone to 600 °C. Place the end with the mixture in the high-temperature zone, and place the growing interdigital electrode in the low-temperature zone at room temperature. S13. After heating for 2 h, wait for it to cool naturally to room temperature. Break the quartz tube and take out the sample on the interdigital electrode. S14. Grind the prepared MoS2 thoroughly. Take out 10 mg of the ground MoS2, 5 mL of chloroplatinic acid, and 20 mL of oxidant and add them to a test tube. Stir the test tube with a magnetic stirrer for 2 h, and set the rotation speed to 550 r / min. S15. Separate the sample using a centrifuge. Heat and dry the reacted MoS2 solution doped with platinum using a vacuum drying oven. Wash the powder three times with deionized water and anhydrous ethanol in sequence, and then platinum-doped MoS2 powder can be obtained.

[0065] The following uses Test Example 1 to illustrate the platinum-doped MoS2 material: Test Example 1: The following takes nitrogen and oxygen in the air as examples. Figure 11 is the adsorption configuration diagram of Pt-MoS2 for oxygen. Figure 12 is the adsorption configuration diagram of Pt-MoS2 for nitrogen. Figure 13 is the adsorption configuration diagram of Pt-MoS2 for C3H2OF6.

[0066] Build a 4×4×1 MoS2 unit cell structure through Material Studio, which contains 9 Mo atoms and 18 S atoms.

[0067] The geometric optimization in this article is completed using the Broyden-Fletcher-Goldfarb-Shanno (BFGS) method of the quickstep package in cp2k. Goedecker-Teter-Hutter (GTH)-PBE is used as the pseudopotential, and DZVP-MOLOPT-SR-GTH is used as the basis set. Considering accuracy and computational cost, DFT-D3 (BJ) is used for dispersion correction in this study.

[0068] The cutoff value and the actual cutoff value are set to 800 and 50 Ry respectively.

[0069] The k-point grid is divided into 5×5×1. And all calculations consider spin polarization. The optimized Mo-S-Mo bond angle is 81.52°, and the Mo-S bond length is 2.426 Å.

[0070] This is basically consistent with the Mo-S-Mo bond angle of 81.52° and the Mo-S bond length of 2.43 Å in the literature, indicating that the parameters and methods used in the present invention are correct and reliable.

[0071] (1) The platinum-doped MoS2 material layer has excellent adsorption properties The calculation formula of the adsorption energy Ead of desflurane and other gases on the Pt-MoS2 surface is as follows: Among them, E Pt-MoS2 、E gas和EPt-MoS2 represent the adsorption system, gas and Pt-MoS respectively. 2的总能量。 Adsorption performance of the gas-sensitive material layer 403: Through theoretical calculation (see Table 5), it is found that the adsorption energy of Pt-MoS2 on C3H2OF6 is -0.834eV, while the adsorption energy on N2 and O2 is only -0.059eV and -0.124eV.

[0072] Table 5 C3H2OF6 N2 O2 Adsorption energy / eV -0.834 eV -0.059 eV -0.124 eV It can be seen that Pt-MoS2 has a strong adsorption effect on polar molecules, which makes Pt bond with the CHF2 group in C3H2OF6, while the adsorption effect on N2 and O2 is weaker.

[0073] (2) The sensing performance of the platinum-doped MoS2 material layer changes after adsorption The relationship between conductivity and band gap is shown in the following formula: Where σ represents conductivity, k is the Boltzmann constant, T is temperature, and B g is the band gap.

[0074] After adsorbing N2 and O2, the band gap of the energy band changes little, which indicates that Pt-MoS2 has low sensitivity to N2 and O2. After adsorbing C3H2OF6, the band gap of the platinum-doped MoS2 material decreases from 1.408eV to 1.110eV, which leads to a significant change in conductivity and good sensitivity ( Figures 14 to 17 (Energy band diagram of Pt-MoS2 material before and after adsorption).

[0075] This indicates that platinum-doped MoS2 has a good adsorption effect on polar molecules. During the adsorption process, it primarily adsorbs the -CHF2 group in the desflurane molecule, forming a Pt-H bond. This facilitates the material's adsorption of desflurane, while its adsorption of N2 and O2 is poor. Good adsorption performance indicates that the gas-sensing material can effectively adsorb gases to the material surface, even gases with low content can be adsorbed and detected, resulting in high detection accuracy.

[0076] In addition, the change in conductivity is relatively obvious before and after the material adsorbs desflurane, showing good sensitivity, while the changes for N2 and O2 are not significant, and other components have little impact on the gas-sensitive material in the sensor. From theoretical calculations, desflurane has a more significant impact on the conductivity of the material and is more likely to cause drift.

[0077] Through the desflurane detection sensor and detection method based on platinum-doped MoS2 interdigital electrodes of this embodiment, real-time monitoring of the desflurane concentration in the air can be achieved. The resistance of the platinum-doped MoS2 material in the sensor can respond quickly within a short time after adsorbing desflurane, with high sensitivity, and its resistance peak is positively correlated with the desflurane concentration, being able to accurately and quickly reflect the desflurane concentration in the air to be measured, being easy to operate, and being able to desorb automatically to achieve repeated application.

[0078] The above embodiments are only exemplary embodiments of the present application and are not used to limit the present application. The protection scope of the present application is defined by the claims. Those skilled in the art can make various modifications or equivalent replacements within the essence and protection scope of the present application, and such modifications or equivalent replacements should also be regarded as falling within the protection scope of the present application.

Claims

1. A diflurane detection sensor based on a platinum-doped MoS2 interdigital electrode, characterized in that, It includes a platinum-doped MoS₂ interdigital electrode (4), an external power supply (6), and an ammeter (5). The platinum-doped MoS₂ interdigital electrode (4), the power supply (6), and the ammeter (5) are connected in series to form a resistive desflurane sensor as a whole, and the resistive desflurane sensor is used to detect the desflurane concentration; Among them, a gas-sensitive material layer (forty-three) composed of platinum-doped MoS₂ is arranged in the sensing area of the platinum-doped MoS₂ interdigital electrode (4). The platinum-doped MoS₂ interdigital electrode (4) includes a sensing electrode (forty-two) connected to the ammeter (5). The sensing electrode (forty-two) and the ammeter (5) jointly measure the resistance of the gas-sensitive material layer (forty-three). After the gas-sensitive material layer (forty-three) adsorbs desflurane, its inherent resistance value changes, and the degree of change in the resistance value of the gas-sensitive material layer (forty-three) is positively correlated with the concentration of desflurane gas flowing on its surface.

2. The diflurane detection sensor based on a platinum-doped MoS2 interdigital electrode according to claim 1, wherein It further includes a heating electrode (forty-four). The heating electrode (forty-four) is arranged between the sensing electrode of the platinum-doped MoS₂ interdigital electrode (4) and the gas-sensitive material layer (forty-three). The heating electrodes (forty-four) are respectively located on both sides of the gas-sensitive material layer (forty-three), and the heating electrode (forty-four) can be connected to an external power supply (6) to heat the gas-sensitive material layer (forty-three).

3. A desflurane detection sensor based on a platinum-doped MoS2 interdigital electrode according to any one of claims 1-2, characterized in that, The preparation method of the platinum-doped MoS₂ interdigital electrode (4) includes the following steps: Add platinum-doped MoS₂ gas-sensitive material powder into ethylene glycol, stir magnetically, and remove the bubbles in the liquid through a numerical control ultrasonic instrument until the powder is evenly dispersed to prepare a slurry; Soak the interdigital electrode in distilled water and absolute ethanol in sequence, and clean it with a numerical control ultrasonic instrument; Inject the slurry into a microelectronic printer, and use the microelectronic printer to coat the slurry on the surface of the coating area of the interdigital electrode to form the gas-sensitive material layer, and attach the heating electrode to the interdigital electrode; Under an insulated state, place the interdigital electrode in a vacuum drying oven, use a vacuum pump to evacuate the vacuum drying oven, heat and dry it, then rinse it with deionized water and absolute ethanol in sequence, and dry it again to obtain the platinum-doped MoS₂ interdigital electrode (4); For every 10 mg of platinum-doped MoS₂ gas-sensitive material, 10 - 30 mL of ethylene glycol is used correspondingly; The rotation speed of the magnetic stirring is 500 r / s - 600 r / s, the stirring time is 5 - 7 h, the rotation speed of the numerical control ultrasonic instrument is 70 - 80 Hz, and the time is 0.5 - 1 h; The drying temperature of the vacuum drying oven is 60 °C - 80 °C, and the drying time is 5 h - 6 h.

4. The difluoroether detection sensor based on a platinum-doped MoS2 interdigital electrode according to claim 3, characterized in that, The preparation method of the platinum-doped MoS₂ gas-sensitive material includes the following steps: Fully grind molybdenum trioxide and sulfur powder and mix them with a transport agent to obtain a mixture. Place the mixture on one side of a vacuum-sealed quartz tube, and place a growth substrate on the other side of the quartz tube, and perform a vacuum treatment on the quartz tube; Place the quartz tube in a two-temperature-zone tube furnace for two-temperature-zone heating. Place the end with the mixture in the high-temperature zone and the growth substrate in the low-temperature zone at room temperature; After the heating time ends, cool to room temperature and take out the sample on the growth substrate; Grind the sample sufficiently. Add chloroplatinic acid and the ground MoS2 into an oxidant, perform magnetic stirring, and obtain a mixed solution after a full reaction. After the stirring is completed, centrifuge the mixed solution, dry the mixed solution to obtain a powder, and wash the powder to obtain the platinum-doped MoS2 gas-sensitive material.

5. The difluoroether detection sensor based on a platinum-doped MoS2 interdigital electrode according to claim 4, wherein, The mass ratio of the molybdenum trioxide, the sulfur powder, and the transport agent is 1:2:5 to 1:2:10; The transport agent is any one of I2 and Br2; The growth substrate is any one of a glass sheet, a sapphire, and a mica sheet; The oxidant uses any one of ascorbic acid, sodium citrate, and sodium borohydride; In the two-temperature zone heating, the high-temperature zone of the two-temperature zone tube furnace is 500 °C to 700 °C, the holding time is 1 h to 2 h, and the low-temperature zone is at room temperature; The time of the magnetic stirring is 1 to 3 h, and the rotation speed is 500 to 600 r / min; The dosage of the ground MoS2 is 10 mg, the dosage of chloroplatinic acid is 5 mL to 15 mL, and the dosage of the oxidant is 15 mL to 25 mL; The solvent for the washing is anhydrous ethanol and deionized water, and the number of times is 3 - 5 times.

6. A detection method for a desflurane detection sensor based on a platinum-doped MoS2 interdigital electrode according to any one of claims 1-5, characterized in that, It includes the following steps: S100. Calibrate the concentration relationship between the concentration of desflurane in the air and the resistance value of the sensor; S200. Place the sensor in the environment to be detected, calculate and obtain the resistance value of the sensor through the ammeter (5), and obtain the desflurane concentration value in the environment to be detected according to the concentration relationship.

7. The detection method according to claim 6, characterized in that, In S100, the calibration method for the correlation between the concentration of desflurane in the air and the resistance value of the gas-sensitive material layer (403) includes the following steps: S110. Construct a detection gas path system for desflurane gas. The detection gas path system for desflurane gas includes a desflurane gas cylinder (1), a high-purity air cylinder (2), a gas mixer (3), and the sensor. The sensor is placed in a box body (8); Connect the air outlets of the desflurane gas cylinder (1) and the high-purity air cylinder (2) to the gas mixer (3), keep the box body (8) in a closed state, the gas mixer (3) is communicated with the box body (8), and the box body (8) has an exhaust pipeline with a controllable passage; S120. Check the airtightness of the gas path, adjust the gas mixer (3) to flush the gas path with desflurane gas, and then use a vacuum pump to pump the closed cavity in the box body (8) to vacuum from the exhaust pipeline, and cycle three times to ensure no impurity gas; S130. Introduce high-purity air into the closed cavity. After waiting for the resistance value of the ammeter (5) to be stable, record the resistance value R0 at this time; S140. Use the gas mixer (3) to configure mixed gases of desflurane and air with different concentrations and introduce them into the closed cavity, record the resistance values R at different concentrations, and obtain the relationship between the change in the resistance value and the concentration of desflurane in the mixed gas.

8. A detection method according to claim 7, characterized in that It also includes the following step: Heat the gas-sensitive material layer (403) to 55 °C through the heating electrode (404).

9. The detection method according to claim 8, wherein Taking the peak resistance of the sensor as Y and the concentration of desflurane in the air as X, the relationship between the peak resistance of the sensor and the concentration of desflurane in the air is: Y = 0.583X + 0.071, R = 0.998; Wherein, the unit of the concentration is ppm.

10. A detection method according to claim 9, characterized in that, The range of the concentration is 2 - 100 ppm.

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