A desflurane detection sensor and method based on platinum-doped MoS2 interdigital electrodes

Abstract

The present invention relates to the field of gas detection technology, and discloses a desflurane detection sensor based on platinum-doped MoS2 interdigital electrodes, comprising interdigital electrodes, a power supply, and an ammeter. The sensing area of ​​the platinum-doped MoS2 interdigital electrodes is provided with a gas-sensitive material layer composed of platinum-doped MoS2. The platinum-doped MoS2 interdigital electrodes include a sensing electrode connected to an ammeter, and the sensing electrode and the ammeter jointly measure the resistance of the gas-sensitive material layer. 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. The invention also discloses a detection method for the desflurane detection sensor based on the platinum-doped MoS2 interdigital electrodes. The invention enables real-time monitoring of desflurane concentration in the air. After desflurane is adsorbed, the resistance of the platinum-doped MoS2 material in the sensor can rapidly respond in a short period of time, resulting in high sensitivity and the ability to automatically desorb, enabling repeated use.

Description

Technical Field

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

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

[0003] However, imperfect administration techniques and defects in anesthetic delivery systems often lead to desflurane leakage and contamination in the operating room. It has been reported that long-term exposure to desflurane may lead to adverse reactions such as cognitive impairment and neurodegeneration. Therefore, desflurane exposure needs to be monitored during desflurane-related procedures.

[0004] Currently, commonly used methods for monitoring anesthetic gas concentrations include infrared measurement, gas chromatography, and mass spectrometry. Detection equipment based on these methods often suffers from high cost, bulk, and low measurement accuracy, making it difficult to accurately monitor desflurane exposure in operating rooms.

[0005] Therefore, a more accurate detection sensor and monitoring method capable of monitoring desflurane concentration in real time are now needed. Summary of the Invention

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

[0007] In order to solve the above technical problems, the present invention specifically provides the following technical solutions:

[0008] The present invention provides a desflurane detection sensor based on a platinum-doped MoS2 interdigital electrode, comprising the 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 to form a resistive desflurane sensor, which is used to detect desflurane concentration.

[0009] In which, the sensing area of ​​the platinum-doped MoS2 interdigital electrode is provided with a gas-sensitive material layer composed of platinum-doped MoS2, and the platinum-doped MoS2 interdigital electrode includes a sensing electrode connected to the ammeter, and 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.

[0010] As a preferred solution of the present invention, it also includes a heating electrode, which is arranged 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. The heating electrodes can be connected to an external power supply and heat the gas-sensitive material layer.

[0011] As a preferred embodiment of the present invention, the method for preparing the platinum-doped MoS2 interdigital electrode comprises the following steps:

[0012] Platinum-doped MoS2 gas-sensitive material powder is added to ethylene glycol, and magnetic stirring is used, and bubbles in the liquid are removed by a digitally controlled ultrasonic device until the powder is uniformly dispersed to prepare a slurry;

[0013] The interdigital electrodes were sequentially immersed in distilled water and anhydrous ethanol and cleaned using a digitally controlled ultrasonic device;

[0014] injecting the slurry into a microelectronic printer, applying the slurry to the surface of the coating area of ​​the interdigital electrode using the microelectronic printer to form the gas-sensitive material layer, and attaching the heating electrode to the interdigital electrode;

[0015] In an insulating state, the interdigitated electrode is placed in a vacuum drying oven, the vacuum drying oven is evacuated using a vacuum pump, and after heating and drying, it is rinsed with deionized water and anhydrous ethanol in sequence, and dried again to obtain the platinum-doped MoS2 interdigitated electrode;

[0016] For every 10 mg of platinum-doped MoS2 gas-sensitive material, 10-30 mL of ethylene glycol is used;

[0017] The magnetic stirring speed is 500r / s~600r / s, the stirring time is 5~7h, the speed of the digital controlled ultrasonic instrument is 70~80Hz, and the stirring time is 0.5-1h;

[0018] The drying temperature of the vacuum drying oven is 60° C. to 80° C., and the drying time is 5 h to 6 h.

[0019] As a preferred embodiment of the present invention, the method for preparing the platinum-doped MoS2 gas-sensitive material comprises the following steps:

[0020] Molybdenum trioxide and sulfur powder are fully ground and mixed with a transport agent to obtain a mixture, the mixture is placed on one side of a vacuum-sealed quartz tube, a growth substrate is placed on the other side of the quartz tube, and the quartz tube is vacuumed;

[0021] The quartz tube is placed in a dual-temperature zone tube furnace for dual-temperature zone heating, with one end containing the mixture placed in the high-temperature zone and the growth substrate placed in the low-temperature zone at room temperature;

[0022] After the heating time is over, the sample is cooled to room temperature and removed from the growth substrate;

[0023] The sample is fully ground, chloroplatinic acid and the ground MoS2 are added to the oxidant, and magnetic stirring is performed to obtain a mixed solution after sufficient reaction. After stirring, the mixed solution is centrifuged and separated, and the mixed solution is dried to obtain powder, and the powder is washed to obtain a platinum-doped MoS2 gas-sensitive material.

[0024] As a preferred embodiment of the present invention, the mass ratio of the molybdenum trioxide, the sulfur powder, and the transport agent is 1:2:5 to 1:2:10;

[0025] The transport agent is any one of I2 and Br2;

[0026] The growth substrate is any one of a glass sheet, a sapphire sheet, and a mica sheet;

[0027] The oxidant is any one of ascorbic acid, sodium citrate and sodium borohydride;

[0028] In the dual-temperature zone heating, the high temperature zone of the dual-temperature zone tubular furnace is 500°C to 700°C, maintained for 1h to 2h, and the low temperature zone is at room temperature;

[0029] The magnetic stirring time is 1-3 hours, and the rotation speed is 500-600 r / min;

[0030] The amount of ground MoS2 is 10 mg, the amount of chloroplatinic acid is 5 mL~15 mL, and the amount of oxidant is 15 mL~25 mL;

[0031] The cleaning solvents are anhydrous ethanol and deionized water, and the number of times is 3-5 times.

[0032] The present invention also discloses a detection method of a desflurane detection sensor based on a platinum-doped MoS2 interdigital electrode, comprising the following steps:

[0033] S100, calibrating the concentration relationship between the concentration of desflurane in the air and the resistance value of the sensor;

[0034] S200 , placing the sensor in an environment to be detected, obtaining a resistance value of the sensor by calculating with the ammeter, and obtaining a desflurane concentration value in the environment to be detected based on the concentration relationship.

[0035] 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:

[0036] S110, constructing a desflurane gas detection gas circuit system, the desflurane gas detection gas circuit system comprising a desflurane gas cylinder, a high-purity air cylinder, a gas distribution instrument, and the sensor, wherein the sensor is placed in the box body;

[0037] Connect the gas outlets of the desflurane gas bottle and the high-purity air bottle to a gas distributor, keep the box body in a sealed state, the gas distributor is in communication with the box body, and the box body has an exhaust pipe with a controllable passage;

[0038] S120, checking the air tightness of the gas circuit, adjusting the gas distribution instrument to flush the gas circuit with desflurane gas, and then using a vacuum pump to evacuate the sealed cavity in the box body through the exhaust pipe to a vacuum state, and performing this cycle three times to ensure that there is no impurity gas;

[0039] S130, introducing high-purity air into the sealed cavity, waiting for the resistance value of the ammeter to stabilize, and recording the resistance value R0 at this time;

[0040] S140, using the gas distribution instrument to prepare mixed gases of desflurane and air of different concentrations and passing them into the closed cavity, recording the resistance values ​​R of different concentrations, and obtaining the relationship between the resistance value change and the concentration of desflurane in the mixed gas.

[0041] As a preferred solution of the present invention, the method further includes the following step: heating the gas-sensitive material layer to 55° C. via the heating electrode.

[0042] As a preferred embodiment of the present invention, the resistance peak of the sensor is Y, the concentration of desflurane in the air is X, and the relationship between the resistance peak of the sensor and the concentration of desflurane in the air is: Y=0.583X+0.071, R=0.998;

[0043] Wherein, the unit of the concentration is ppm.

[0044] Compared with the prior art, the present invention has the following beneficial effects:

[0045] The present invention connects a gas-sensitive resistor composed of platinum-doped MoS2 material in series with an ammeter and a power supply. When an electrode containing this material is placed in an environment to be detected, it can absorb desflurane in the environment to be detected, causing its inherent conductivity to change. The ammeter value of the interdigital electrode resistance is detected in real time, thereby achieving real-time monitoring of the desflurane concentration in the environment. The conductivity of the gas-sensitive resistor can respond quickly in seconds, and the reaction is sensitive.

[0046] The gas-sensitive resistor sensor of the present invention has a detected resistance peak that is positively correlated with the concentration of desflurane flowing on its surface. The resistor element not only adsorbs desflurane but also automatically desorbs and rapidly releases gas when the desflurane concentration in the air decreases, rapidly recovering its inherent conductivity. By detecting the change in the resistance value of the interdigital electrodes, the concentration of desflurane in the air can be dynamically balanced and monitored, making it easy to operate.

[0047] The present invention provides a heating electrode on the platinum-doped MoS2 material gas sensor, which can achieve dynamic equilibrium of the reaction during the detection process and control the desorption efficiency through temperature control, thereby realizing the repeated use of the gas-sensitive interdigital electrodes in the sensor;

[0048] The present invention provides a method for detecting desflurane, which 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 results in an ammeter. The detection concentration is linearly correlated with the detection value, and the method is easy to use. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] To more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for the embodiments or the description of the prior art. Obviously, the drawings described below are merely exemplary, and those skilled in the art can derive other implementation drawings based on the provided drawings without inventive effort.

[0050] Figure 1 The present invention provides a schematic diagram of the connection structure of a desflurane detection sensor based on platinum-doped MoS2 interdigital electrodes;

[0051] Figure 2 The present invention provides Figure 1 A schematic structural diagram of the interdigitated electrodes in the embodiment shown;

[0052] Figure 3 The present invention provides a partial structural schematic diagram of a desflurane detection sensor based on platinum-doped MoS2 interdigital electrodes in Example 1;

[0053] Figure 4 The present invention provides a structural schematic diagram of a desflurane detection sensor based on platinum-doped MoS2 interdigital electrodes in Example 1;

[0054] Figure 5 The present invention provides a schematic diagram of the gas detection system for desflurane gas as shown in Example 1;

[0055] Figure 6Provides a gas-sensitive test result diagram of the sensor to standard gases of different concentrations for the present invention;

[0056] Figure 7 Provide a linear relationship diagram between standard gas concentration and response value based on fitting for the present invention;

[0057] Figure 8 Provides a gas-sensitive test result diagram of the sensor to standard gases at different temperatures for the present invention;

[0058] Figure 9 The present invention provides a flow chart of a method for preparing a platinum-doped MoS2 interdigital electrode;

[0059] Figure 10 The present invention provides a schematic flow chart of a method for preparing a platinum-doped MoS2 gas-sensitive material;

[0060] Figure 11 Provided is the adsorption configuration diagram of oxygen by Pt-MoS2 shown in Detection Example 1 of the present invention;

[0061] Figure 12 The present invention provides a configuration diagram of the adsorption of nitrogen by Pt-MoS2 as shown in Detection Example 1;

[0062] Figure 13 Provided is the adsorption configuration diagram of Pt-MoS2 on C3H2OF6 shown in Detection Example 1 of the present invention;

[0063] Figure 14 Provide a band gap diagram of the Pt-MoS2 energy band shown in Detection Example 1 for the present invention;

[0064] Figure 15 Provided for the present invention is a graph showing the band gap change of the energy band of Pt-MoS2 to adsorb N2 as shown in Detection Example 1;

[0065] Figure 16 Provided for the present invention is a graph showing the band gap change of the energy band of Pt-MoS2 for oxygen adsorption as shown in Detection Example 1;

[0066] Figure 17 The present invention provides a band gap change diagram of the energy band of Pt-MoS2 for adsorbing C3H2OF6 shown in detection example 1.

[0067] The numbers in the figure represent the following:

[0068] 1- Desflurane gas bottle;

[0069] 2-High purity air bottle;

[0070] 3-Gas distribution instrument;

[0071] 4-interdigitated electrode; 401-substrate; 402-sensing electrode; 403-gas sensitive material layer; 404-heating electrode;

[0072] 5- Ammeter;

[0073] 6- Power supply;

[0074] 7-Wire set;

[0075] 8-box body;

[0076] 9-sealing plate;

[0077] 10-intake pipe;

[0078] 11- Exhaust pipe. DETAILED DESCRIPTION

[0079] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0080] like Figure 1 and Figure 2 As shown, the present invention provides a desflurane detection sensor based on platinum-doped MoS2 interdigital electrodes, including interdigital electrodes 4, a power supply 6 and an ammeter 5. The platinum-doped MoS2 interdigital electrodes 4, the power supply 6 and the ammeter 5 are connected in series to form a resistive desflurane sensor.

[0081] The interdigitated electrode 4 comprises a dielectric layer on a substrate 401, above which are arranged a sheet-like 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, multiple carbon nanotube electrodes are arranged in an interdigitated electrode shape, forming an attachment area for the platinum-doped MoS2 material. This attachment area for the platinum-doped MoS2 material serves as a gas-sensitive material layer 403, which is configured to contact the gas being measured.

[0082] The power supply 6 is connected to the ammeter 5 , and 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 .

[0083] The operating principle of the desflurane detection sensor based on platinum-doped MoS2 interdigital electrodes is as follows:

[0084] After the gas-sensitive material layer 403 is able to adsorb desflurane, its inherent resistance value changes, and the value of the ammeter 5 changes. The response sensitivity of the platinum-doped MoS2 material is high and the speed is fast;

[0085] 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, thereby realizing real-time monitoring of desflurane without human intervention and can be used repeatedly.

[0086] This desflurane detection sensor is a gas sensor that can detect whether the air contains desflurane. The usage of this desflurane detection sensor is as follows:

[0087] Keep the sensor power supply 6 stable, place the platinum-doped MoS2 interdigital electrode 4 in the environment to be tested, and observe the index of the ammeter 5. Changes in the value of the ammeter 5 indicate that the environment to be tested contains desflurane.

[0088] This desflurane detection sensor can be directly applied to environments where desflurane anesthetic gas is required, such as operating rooms.

[0089] Through actual use, it can be seen 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 electrodes 4, power supply 6, ammeter 5, and wire group 7 arranged in the box body 8, and the top of the box body 8 is open.

[0090] This desflurane detection sensor is a gas sensor used to detect the concentration of desflurane in the air. The following provides a method for detecting the concentration of desflurane using a desflurane detection sensor based on a platinum-doped MoS2 interdigital electrode, comprising the following steps:

[0091] S100, calibrating the concentration relationship between the concentration of desflurane in the air and the resistance value of the gas-sensitive material layer 403;

[0092] S200 , placing the sensor in an environment to be detected, calculating the resistance value of the sensor using the ammeter 5 , and obtaining the desflurane concentration value in the environment to be detected based on the concentration relationship.

[0093] In the present invention, the resistance of the gas-sensitive material layer 403 on the sensor is positively correlated with the concentration of desflurane in the air. At the same time, in a stable current, the value displayed by the ammeter 5 is also linearly correlated with the resistance. Therefore, the index value of the ammeter 5 is linearly correlated with the concentration of desflurane in the air. After actually detecting this correlation, this correlation is obtained through a formula, and real-time monitoring can be achieved.

[0094] It can be seen that the present invention connects a gas-sensitive resistor composed of 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, no manual operation is required. The gas-sensitive material in the sensor can automatically absorb desflurane in the environment to be detected, and its inherent conductivity will change. The ammeter value of the real-time detection of the interdigital electrode resistance will change, thereby realizing real-time monitoring of the desflurane concentration in the environment.

[0095] Furthermore, a calibration method for the correlation between the concentration of desflurane in air and the resistance value of the gas-sensitive material layer 403 is provided below, comprising the following steps:

[0096] S110, constructing a desflurane gas detection gas circuit system, the desflurane gas detection gas circuit system comprising a desflurane gas cylinder 1, a high-purity air cylinder 2, a gas distribution device 3, and a sensor, wherein the sensor is placed in a box body 8;

[0097] Connect the gas outlets of the desflurane gas bottle 1 and the high-purity air bottle 2 to the gas distributor 3, keep the box body 8 in a sealed state, the gas distributor 3 is connected to the box body 8, and the box body 8 has an exhaust pipe with a controllable passage;

[0098] S120, check the air tightness of the gas circuit, adjust the gas distribution device 3 to flush the gas circuit with desflurane gas, and then use a vacuum pump to evacuate the closed cavity in the box body 8 through the exhaust pipe to a vacuum state, and repeat this cycle three times to ensure that there is no impurity gas;

[0099] S130, introducing high-purity air into the sealed cavity, waiting for the resistance value of the ammeter 5 to stabilize, and recording the resistance value R0 at this time;

[0100] S140. Use the gas distributor 3 to prepare mixed gases of desflurane and air of different concentrations and introduce them into the sealed cavity. Record the resistance values ​​R of the different concentrations and obtain the relationship between the resistance value change and the concentration of desflurane in the mixed gas.

[0101] Furthermore, the sensitivity of the sensor is temperature-dependent. The present invention uses a heating device to control the degree of resistivity change and desorption time of the sensor. Specifically, heating electrodes 404 are provided on the interdigital electrodes 4. Heating electrodes 404 are positioned between the sensing electrodes of the interdigital electrodes 4 and the gas-sensitive material layer 403. Heating electrodes 404 are located on both sides of the gas-sensitive material layer 403 and can be connected to an external power source to control the temperature of the interdigital electrodes 4. The gas-sensitive material layer 403 is heated by heating electrodes 404, and the most sensitive temperature of the sensor is determined by the degree of resistivity change.

[0102] The following examples verify the detection method of the sensor:

[0103] ① Device selection: This embodiment provides a sensor, which has the same function as the above sensor, specifically, Figures 3 and 4 As shown, this sensor includes the above-mentioned platinum-doped MoS2 interdigital electrode 4, power supply 6, ammeter 5, and wire group 7. An air inlet pipe 10 and an air outlet pipe 11 are respectively provided on both sides of the box body 8. A sealing plate 9 is provided above the box body 8. Except for the connection position between the air inlet pipe 10 and the air outlet pipe 11, the entire box body 8 and the sealing plate 9 form a closed chamber.

[0104] The power supply 6 and the ammeter 5 are connected in series via a wire group 7 . The wire group 7 can be connected to the heating electrode 404 separately to change the temperature via the heating electrode 404 .

[0105] ② Construction Figure 5 The gas detection system of desflurane gas includes: a desflurane gas bottle 1, a high-purity air bottle 2, a gas distributor 3, and a sensor.

[0106] ③ Operation: Calibrate the concentration relationship between the concentration of desflurane in the air and the resistance value of the gas-sensitive material layer 403:

[0107] 1. Connect the gas outlets of the desflurane gas bottle 1 and the high-purity air bottle 2 to the gas distributor 3, keep the sealing plate 9 in a sealed state, and connect the gas distributor 3 to the box body 8 through the air inlet pipe 10;

[0108] 2. Check the air tightness of the gas circuit, adjust the gas distributor 3 to flush the gas circuit with desflurane gas, and then use a vacuum pump to evacuate the sealed cavity in the box body 8 through the exhaust pipe. Repeat this cycle three times to ensure that there is no impurity gas.

[0109] 3. Introduce high-purity air into the sealed chamber, wait for the resistance value of ammeter 5 to stabilize, and record the resistance value R0 at this time;

[0110] 4. Use the gas distributor 3 to prepare a mixture of desflurane and air of different concentrations and introduce it into the closed cavity until the resistance value stabilizes. Record the resistance value R of different concentrations and obtain the relationship between the resistance value change and the concentration of desflurane in the mixed gas.

[0111] Record the resistance change of the interdigitated electrode 4 at different concentrations:

[0112]

[0113] The resistance change rate data of Example 1 are as follows (temperature is 55°C):

[0114] The sensor's response speed at different concentrations, i.e., the resistance peak, is shown in Figure 2. Figure 6 shown.

[0115] use Figure 7The linear relationship obtained by fitting the curve is used to measure the measurement results of mixed gases of other concentrations as shown in Table 1. It can be seen that the errors of the above sensors are all within 5%, which meets the actual application requirements.

[0116] Table 1

[0117] 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

[0118] Multiple embodiments are provided, and the difference lies in that the heating temperature of the heating electrode 404 is different.

[0119] Compare the resistance change rate of the sensor at different temperatures, and the characterization results are shown in Figure 8 .

[0120] See Table 2 for specific data:

[0121] Table 2

[0122] Temperature / ℃ ΔR% 25 7.698 35 11.253 45 17.892 55 29.163 65 22.095 75 19.257

[0123] It can be seen from Table 3 that when the temperature is 55°C, the response parameter is the highest.

[0124] By changing the heating temperature of the heating electrode in Example 1, the resistance change rate of the sensor at different temperatures was calculated. The resistance change rate values ​​at different temperatures are shown in Table 3:

[0125] Table 3

[0126] Temperature / ℃ Change rate / % 25 7.698 35 11.253 45 17.892 55 29.163 65 22.095 75 19.257

[0127] From the results in 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 operating temperature for the desflurane detection sensor with platinum-doped MoS2 interdigital electrodes in Example 1.

[0128] Comparison of the response parameters of the interdigital electrode to 10 ppm desflurane at different temperatures. See Figure 16 The desorption time is calculated as the time from the response peak to the time when the response value reaches 10% of the response peak.

[0129] Table 5 shows the desorption time 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 operating temperature of this resistance sensor is 55°C.

[0130] Table 4

[0131] Temperature / ℃ 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

[0132] The electric heating function can achieve a dynamic balance of the reaction during the detection process and control the desorption efficiency (for example, increasing the heating temperature after ventilation is completed to achieve rapid desorption), thereby realizing the repeated use of the gas-sensitive interdigital electrodes in the sensor.

[0133] The performance evaluation method is to configure the interdigital electrodes into sensors for detection. The results of this method are 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. Figure 6 The response time of the resistance is in seconds, and the difference in the resistance peak value of the sensor is large in the desflurane environment with different concentrations, which is convenient for judgment and easy to distinguish.

[0134] Figure 7 The linear relationship between the fitted standard gas concentration and the response value at the optimal temperature is obtained. The response value is the peak value of the gas-sensitive material resistance displayed in the electrochemical workstation 5. Through the corresponding relationship, the data displayed in the electrochemical workstation can be associated with desflurane, thereby realizing direct reading of the desflurane concentration data.

[0135] Since the peak resistance is measured by 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 peak resistance of the interdigital electrode 4 show a linear relationship. This linear relationship is: with 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; the concentration range is 2-100 ppm.

[0136] It can be seen that the sensor can detect desflurane in the concentration range of 2-100ppm, has a sensitive reaction, a short response time, and a high sensitivity. The desflurane in the gas is linearly correlated with the resistance change, making it easy to read the concentration of desflurane. After the desflurane gas concentration drops, the sensor can automatically desorb and can be reused without intervention. It has a simple structure and convenient operation. At the same time, by heating the sensor, it can achieve a dynamic balance of the reaction during the detection process and control the desorption efficiency (for example, by increasing the heating temperature after ventilation is completed to achieve rapid desorption), thereby realizing the repeated use of the gas-sensitive interdigital electrodes in the sensor.

[0137] like Figure 9 As shown, the present invention further provides a method for preparing the above-mentioned platinum-doped MoS2 interdigital electrode, comprising the following steps:

[0138] Platinum-doped MoS2 gas-sensitive material powder is added to ethylene glycol, and magnetic stirring is used, and bubbles in the liquid are removed by a digitally controlled ultrasonic device until the powder is uniformly dispersed to prepare a slurry;

[0139] The interdigital electrodes were sequentially immersed in distilled water and anhydrous ethanol and cleaned using a digitally controlled ultrasonic device;

[0140] injecting the slurry into a microelectronic printer, and coating the slurry on the surface of the coating area of ​​the interdigital electrode using the microelectronic printer to form a gas-sensitive material layer;

[0141] In an insulating state, the interdigitated electrodes were placed in a vacuum drying oven, evacuated using a vacuum pump, heated and dried, and then rinsed with deionized water and anhydrous ethanol in sequence, and dried again to obtain platinum-doped MoS2 interdigitated electrodes.

[0142] Preferably, 10 to 30 mL of ethylene glycol is used for every 10 mg of platinum-doped MoS2 gas-sensitive material.

[0143] Preferably, the speed of the magnetic stirring is 500 r / s to 600 r / s, the stirring time is 5 to 7 hours, and the speed of the digitally controlled ultrasonic instrument is 70 to 80 Hz, and the stirring time is 0.5 to 1 hour.

[0144] Preferably, the drying temperature of the vacuum drying oven is 60° C. to 80° C., and the drying time is 5 h to 6 h.

[0145] Specifically, the steps for preparing the electrodes used in the above-mentioned sensor are as follows:

[0146] S21, add platinum-doped MoS2 powder and 20 mL of ethylene glycol into a test tube;

[0147] S22. To make the platinum-doped MoS2 uniformly dispersed in the solution, the test tube was stirred with a magnetic stirrer at a speed of 600 r / min for 6 h, and then a digitally controlled ultrasonic device was used to vibrate the solution for a period of time to destroy the bubbles inside the solution for 1 h.

[0148] S23, soak the original interdigital electrodes in distilled water and anhydrous ethanol in turn and clean them using a digitally controlled ultrasonic device three times, each time for 30 minutes, to ensure that the original interdigital electrodes are absolutely clean;

[0149] S24, dispersing platinum-doped MoS2 powder in a solution to form a slurry, injecting the slurry into a microelectronic printer, and coating the slurry on the surface of the coating area of ​​the original interdigital electrode to form a gas-sensitive material layer 403;

[0150] S25. While ensuring insulation, place the original interdigitated electrode in a vacuum drying oven, evacuate the oven using a vacuum pump, and then heat to 70°C and dry for 6 hours;

[0151] S26 , using deionized water and anhydrous ethanol to rinse the original interdigitated electrodes and the gas-sensitive material layer 403 after the slurry is applied, and then drying.

[0152] The preparation of this platinum-doped MoS2 interdigital electrode 4 uses existing interdigital electrodes. The difference is that this platinum-doped MoS2 interdigital electrode is covered with platinum-doped MoS2 material. This platinum-doped MoS2 can be applied to the sensor after processing.

[0153] like Figure 10 As shown, the preparation method of the platinum-doped MoS2 gas-sensitive material is as follows: molybdenum trioxide and sulfur powder are fully ground and mixed with a transport agent to obtain a mixture, the mixture is placed on one side of a vacuum-sealed quartz tube, a growth substrate is placed on the other side of the quartz tube, and the quartz tube is vacuumed;

[0154] The quartz tube is placed in a dual-temperature zone tube furnace for dual-temperature zone heating, with one end containing the mixture placed in the high-temperature zone and the growth substrate placed in the low-temperature zone at room temperature;

[0155] After the heating time is over, the sample is cooled to room temperature and removed from the growth substrate;

[0156] The sample is fully ground, chloroplatinic acid and the ground MoS2 are added to the oxidant and magnetically stirred to obtain a mixed solution after sufficient reaction. After stirring, the mixed solution is centrifuged and dried to obtain powder, which is then washed to obtain a platinum-doped MoS2 gas-sensitive material.

[0157] Preferably, the mass ratio of molybdenum trioxide, sulfur powder and transport agent is 1:2:5~1:2:10.

[0158] Preferably, the transport agent is any one of I2 and Br2.

[0159] Preferably, the growth substrate is any one of a glass sheet, a sapphire sheet, and a mica sheet.

[0160] Preferably, the oxidizing agent is any one of ascorbic acid, sodium citrate and sodium borohydride.

[0161] Preferably, in the dual-temperature zone heating, the high temperature zone of the dual-temperature zone tubular furnace is 500° C. to 700° C., the maintenance time is 1 h to 2 h, and the low temperature zone is at room temperature.

[0162] Preferably, the magnetic stirring time is 1-3 hours, and the rotation speed is 500-600 r / min.

[0163] Preferably, the amount of ground MoS2 is 10 mg, the amount of chloroplatinic acid is 5 mL to 15 mL, and the amount of oxidant is 15 mL to 25 mL.

[0164] Preferably, the cleaning solvent is anhydrous ethanol and deionized water, and the number of times is 3-5 times.

[0165] Specifically, the preparation method of the MoS2 gas-sensitive material used in the platinum-doped MoS2 interdigital electrode 4 is as follows:

[0166] S11. Grind molybdenum trioxide and sulfur powder thoroughly and mix them with iodine. The ratio of molybdenum trioxide, sulfur powder, and iodine is 1:2:5. Place the mixture on one side of a vacuum-sealed quartz tube. Place a growth interdigital electrode on the other side of the quartz tube. Vacuum the quartz tube.

[0167] S12, placing the quartz tube in a dual-temperature zone tube furnace, heating the high-temperature zone to 600°C, placing the end containing the mixture in the high-temperature zone, and placing the interdigitated electrode in the low-temperature zone at room temperature;

[0168] S13, after heating for 2 hours, wait for the temperature to naturally cool to room temperature, destroy the quartz tube and remove the sample on the interdigital electrode;

[0169] S14, the prepared MoS2 was fully ground, 10 mg of the ground MoS2, 5 mL of chloroplatinic acid and 20 mL of oxidant were added to a test tube, and the test tube was stirred with a magnetic stirrer for 2 h at a speed of 550 r / min;

[0170] S15. Separate the sample using a centrifuge, heat and dry the reacted MoS2 solution doped with platinum in a vacuum drying oven, and wash the powder three times with deionized water and anhydrous ethanol in sequence to obtain platinum-doped MoS2 powder.

[0171] The following is an explanation of the platinum-doped MoS2 material through Test Example 1:

[0172] Test Example 1:

[0173] The following takes nitrogen and oxygen in the air as an example. 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 This is the adsorption configuration diagram of Pt-MoS2 on C3H2OF6.

[0174] A 4×4×1 MoS2 unit cell structure is created using Material Studio, which contains 9 Mo atoms and 18 S atoms.

[0175] The geometry optimization in this paper was performed using the Broyden-Fletcher-Goldfarb-Shanno (BFGS) method in the quickstep package within cp2k. Goedecker-Teter-Hutter (GTH)-PBE was used as the pseudopotential, and DZVP-MOLOPT-SR-GTH was used as the basis set. For reasons of accuracy and computational cost, DFT-D3 (BJ) was used for dispersion correction.

[0176] The cutoff value and actual cutoff value were set to 800 and 50 Ry, respectively.

[0177] The K-point grid was divided into 5 × 5 × 1 points. All calculations took spin polarization into account. The optimized Mo-S-Mo bond angle was 81.52°, and the Mo-S bond length was 2.426 Å.

[0178] 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.

[0179] (1) The platinum-doped MoS2 material layer has excellent adsorption properties

[0180] The calculation formula of the adsorption energy Ead of desflurane and other gases on the Pt-MoS2 surface is as follows:

[0181]

[0182] Among them, E Pt-MoS2 、E gas和EPt-MoS2 represent the adsorption system, gas and Pt-MoS respectively. 2的总能量。

[0183] Adsorption performance of the gas-sensitive material layer 403:

[0184] 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.

[0185] Table 5

[0186] C3H2OF6 N2 O2 Adsorption energy / eV -0.834eV -0.059eV -0.124eV

[0187] 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.

[0188] (2) The sensing performance of the platinum-doped MoS2 material layer changes after adsorption

[0189] The relationship between conductivity and band gap is shown in the following formula:

[0190]

[0191] Where σ represents conductivity, k is the Boltzmann constant, T is temperature, and B g is the band gap.

[0192] 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).

[0193] 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.

[0194] In addition, the conductivity of the material changes significantly before and after the adsorption of desflurane, showing good sensitivity, while N2 and O2 are not significant enough. Other components have little effect on the gas-sensitive material in the sensor. From theoretical calculations, it can be seen that desflurane has a more significant effect on the conductivity of the material and is more likely to cause offset.

[0195] Through the desflurane detection sensor and detection method based on the platinum-doped MoS2 interdigital electrode 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 in a short time after adsorbing desflurane, with high sensitivity, and its resistance peak is positively correlated with the desflurane concentration. It can accurately and quickly reflect the desflurane concentration in the air to be tested, is easy to operate, and can automatically desorb, realizing repeated use.

[0196] The above embodiments are merely exemplary embodiments of the present application and are not intended to limit the scope of the present application. The scope of protection of the present application is defined by the claims. Those skilled in the art may make various modifications or equivalent substitutions to the present application within the essence and scope of protection of the present application, and such modifications or equivalent substitutions shall also be deemed to fall within the scope of protection of the present application.

Claims

1. A desflurane detection sensor based on platinum-doped MoS2 interdigital electrodes, characterized in that: It comprises a platinum-doped MoS2 interdigital electrode (4), an external power supply (6) and an ammeter (5), wherein the platinum-doped MoS2 interdigital electrode (4), the power supply (6) and the ammeter (5) are connected in series to form a resistance-type desflurane sensor, and the resistance-type desflurane sensor is used to detect the concentration of desflurane; The sensing area of ​​the platinum-doped MoS2 interdigital electrode (4) is provided with a gas-sensitive material layer (403) composed of platinum-doped MoS2, the platinum-doped MoS2 interdigital electrode (4) includes a sensing electrode (402) connected to the ammeter (5), the sensing electrode (402) and the ammeter (5) jointly measure the resistance of the gas-sensitive material layer (403), and after the gas-sensitive material layer (403) adsorbs desflurane, its inherent resistance value changes, and 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; The invention also includes a heating electrode (404), which is arranged between the sensing electrode of the platinum-doped MoS2 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 electrodes (404) can be connected to an external power supply (6) and heat the gas-sensitive material layer (403).

2. The desflurane detection sensor based on platinum-doped MoS2 interdigital electrodes according to claim 1, characterized in that: The method for preparing the platinum-doped MoS2 interdigital electrode (4) comprises the following steps: Platinum-doped MoS2 gas-sensitive material powder is added to ethylene glycol, and magnetic stirring is used, and bubbles in the liquid are removed by a digitally controlled ultrasonic device until the powder is uniformly dispersed to prepare a slurry; The interdigital electrodes were sequentially immersed in distilled water and anhydrous ethanol and cleaned using a digitally controlled ultrasonic device; injecting the slurry into a microelectronic printer, applying the slurry to the surface of the coating area of ​​the interdigital electrode using the microelectronic printer to form the gas-sensitive material layer, and attaching the heating electrode to the interdigital electrode; In an insulating state, the interdigitated electrode is placed in a vacuum drying oven, the vacuum drying oven is evacuated using a vacuum pump, and after heating and drying, it is rinsed with deionized water and anhydrous ethanol in sequence, and dried again to obtain the platinum-doped MoS2 interdigitated electrode (4); For every 10 mg of platinum-doped MoS2 gas-sensitive material, 10-30 mL of ethylene glycol is used; The magnetic stirring speed is 500r / s~600r / s, the stirring time is 5~7h, the speed of the digital controlled ultrasonic instrument is 70~80Hz, and the stirring time is 0.5-1h; The drying temperature of the vacuum drying oven is 60° C. to 80° C., and the drying time is 5 h to 6 h.

3. The desflurane detection sensor based on platinum-doped MoS2 interdigital electrodes according to claim 2, characterized in that: The preparation method of the platinum-doped MoS2 gas-sensitive material comprises the following steps: Molybdenum trioxide and sulfur powder are fully ground and mixed with a transport agent to obtain a mixture, the mixture is placed on one side of a vacuum-sealed quartz tube, a growth substrate is placed on the other side of the quartz tube, and the quartz tube is vacuumed; The quartz tube is placed in a dual-temperature zone tube furnace for dual-temperature zone heating, with one end containing the mixture placed in the high-temperature zone and the growth substrate placed in the low-temperature zone at room temperature; After the heating time is over, the sample is cooled to room temperature and removed from the growth substrate; The sample is fully ground, chloroplatinic acid and the ground MoS2 are added to the oxidant, and magnetic stirring is performed to obtain a mixed solution after sufficient reaction. After stirring, the mixed solution is centrifuged and separated, and the mixed solution is dried to obtain powder, and the powder is washed to obtain a platinum-doped MoS2 gas-sensitive material.

4. The desflurane detection sensor based on platinum-doped MoS2 interdigital electrodes according to claim 3, characterized in that: 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 sheet, and a mica sheet; The oxidant is any one of ascorbic acid, sodium citrate and sodium borohydride; In the dual-temperature zone heating, the high temperature zone of the dual-temperature zone tubular furnace is 500°C to 700°C, maintained for 1h to 2h, and the low temperature zone is at room temperature; The magnetic stirring time is 1-3 hours, and the rotation speed is 500-600 r / min; The amount of ground MoS2 is 10 mg, the amount of chloroplatinic acid is 5 mL~15 mL, and the amount of oxidant is 15 mL~25 mL; The cleaning solvents are anhydrous ethanol and deionized water, and the number of times is 3-5 times.

5. A detection method for a desflurane detection sensor based on a platinum-doped MoS2 interdigital electrode according to any one of claims 1 to 4, characterized in that: The steps include: S100, calibrating the concentration relationship between the concentration of desflurane in the air and the resistance value of the sensor; S200, placing the sensor in the environment to be detected, calculating the resistance value of the sensor by the ammeter (5), and obtaining the desflurane concentration value in the environment to be detected based on the concentration relationship.

6. A detection method according to claim 5, 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) comprises the following steps: S110, constructing a desflurane gas detection gas circuit system, the desflurane gas detection gas circuit system comprising a desflurane gas bottle (1), a high-purity air bottle (2), a gas distribution device (3), and the sensor, wherein the sensor is placed in a box body (8); The gas outlets of the desflurane gas bottle (1) and the high-purity air bottle (2) are connected to the gas distributor (3), and the box body (8) is kept in a sealed state. The gas distributor (3) is communicated with the box body (8), and the box body (8) has an exhaust pipe with a controllable passage; S120, check the air tightness of the gas circuit, adjust the gas distribution device (3) to flush the gas circuit with desflurane gas, and then use a vacuum pump to evacuate the closed cavity in the box body (8) from the exhaust pipe to a vacuum state, and repeat the cycle three times to ensure that there is no impurity gas; S130, introducing high-purity air into the sealed cavity, waiting for the resistance value of the ammeter (5) to stabilize, and recording the resistance value R0 at this time; S140, using the gas distribution device (3) to prepare mixed gases of desflurane and air of different concentrations and passing them into the closed cavity, recording the resistance values ​​R of different concentrations, and obtaining the relationship between the resistance value change and the concentration of desflurane in the mixed gas.

7. A detection method according to claim 6, characterized in that, The method further comprises the following step: heating the gas-sensitive material layer (403) to 55°C via the heating electrode (404).

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