Gas detection device and gas concentration detection method

Abstract

The application relates to a gas detection device and a gas concentration detection method. The gas detection device comprises a micro-detection chamber, a power source, an air outlet, a gas diffusion resistance element, and a working electrode. The volume of the micro-detection chamber is fixed, and the micro-detection chamber is provided with an air inlet. The power source is connected with the micro-detection chamber. The air outlet is connected with the power source. The gas diffusion resistance element is arranged in the micro-detection chamber. The working electrode is connected with the gas diffusion resistance element, and the working electrode is provided with a catalytic material. The working electrode is used for detecting a response value of a to-be-detected gas concentration and / or consuming the to-be-detected gas. The gas detection device has a small volume and a simple structural design. When the gas concentration is detected, a small amount of gas is required. According to specific experimental requirements, the gas detection device with different structural features can be used for measuring a single gas concentration or a mixed gas concentration.

Description

Technical Field

[0001] This application relates to the field of gas concentration detection technology, and more specifically, to a gas detection device and a gas concentration detection method. Background Technology

[0002] Currently, commercially available current-type electrochemical gas sensors typically measure gas concentration by utilizing the relationship between the steady-state response current of the analyte gas and its concentration. These sensors are used in both stationary and portable gas analysis instruments, and their sampling methods generally fall into two categories. One is the diffusion method, where the sensor is placed in the target environment, and the analyte gas enters the sensor / detector through gas diffusion. The other is the gas-flow method, where the analyte gas is continuously introduced into the sensor via a gas pump. Both methods have relatively slow sensor response times, requiring a longer time to obtain the steady-state response current, and necessitate a larger gas volume for measurement. When the amount of analyte gas is small, these two methods are suitable for concentration detection. Summary of the Invention

[0003] The purpose of this application is to provide a gas detection device and a gas concentration detection method. The gas detection device has a simple structure and small size, and can realize the separate detection of multiple gas components in a mixed gas according to experimental requirements.

[0004] In a first aspect, this application provides a gas detection device, comprising:

[0005] A micro-detection chamber, the micro-detection chamber having a fixed volume, and the micro-detection chamber being provided with an air inlet;

[0006] A power source is connected to the micro-detection chamber;

[0007] The air outlet is connected to the power source;

[0008] A gas diffusion resistance element is disposed within the micro-detection chamber; and

[0009] The working electrode is connected to the gas diffusion resistance component and is provided with a catalytic material for detecting the concentration response value of the gas to be tested and / or consuming the gas to be tested.

[0010] In one embodiment, there is at least one gas diffusion resistance element; there is at least one working electrode.

[0011] In one embodiment, the gas detection device further includes: at least one independent detection unit disposed in the micro detection chamber;

[0012] Each of the independent detection units is provided with a gas diffusion resistance element and a corresponding connected working electrode.

[0013] In one embodiment, the working electrode is either a consumable detection electrode or a non-consumable detection electrode.

[0014] In one embodiment, the power source is an air pump.

[0015] Secondly, this application provides a gas concentration detection method, comprising:

[0016] The gas to be tested is introduced into the micro-detection chamber;

[0017] Within a preset measurement time window, the working electrode detects the response value of the gas to be measured;

[0018] Based on the response value, the concentration of the gas to be tested is obtained.

[0019] In one embodiment, the step of detecting the response value of the gas to be measured by the working electrode within a preset measurement time window includes:

[0020] When a single gas to be tested is introduced into the micro-detection chamber, the current value corresponding to the single gas to be tested detected by the working electrode within a preset measurement time window is obtained.

[0021] The current value is processed to obtain the response value of the single gas to be tested detected by the working electrode.

[0022] In one embodiment, the step of detecting the response value of the gas to be measured by the working electrode within a preset measurement time window includes:

[0023] The electrical charge value of the zero-point gas (excluding the gas to be measured) detected by the working electrode within the preset measurement time window is obtained as the first electrical charge value.

[0024] Within the same preset measurement time window, the amount of electricity consumed by the gas to be measured detected by the working electrode is obtained as the second amount of electricity.

[0025] The difference between the second charge value and the first charge value is processed to obtain the response value of the single gas to be tested detected by the working electrode.

[0026] In one embodiment, the step of detecting the response value of the gas to be measured by the working electrode within a preset measurement time window includes:

[0027] When the mixed gas to be tested is introduced into the micro detection chamber and there is no gas filter in the micro detection chamber, the electrical charge value corresponding to the mixed gas detected by the working electrode is obtained as the electrical charge value one.

[0028] When a gas filtration device is present in the detection chamber, the electrical charge value of the mixed gas to be tested detected by the working electrode is obtained as the second electrical charge value.

[0029] The difference between the second electrical charge value and the first electrical charge value is processed to obtain the response value of the gas to be tested after complete reaction in the micro-detection chamber.

[0030] In one embodiment, the step of detecting the response value of the gas to be measured by the working electrode within a preset measurement time window includes:

[0031] The gas mixture to be tested is introduced into the micro-detection chamber;

[0032] Obtain the charge value of the mixed gas detected by the working electrode within the first preset sampling time window;

[0033] Obtain the charge value of the mixed gas detected by the working electrode within the second preset sampling time window;

[0034] Obtain the charge value of the mixed gas detected by the working electrode within the third preset sampling time window;

[0035] Based on the charge value of the mixed gas within the first preset sampling time window, the charge value of the mixed gas within the second preset sampling time window, and the charge value of the mixed gas within the third preset sampling time window, the response values ​​of different gas components in the mixed gas are obtained.

[0036] The advantages of this application compared to existing technologies are: the gas detection device of this application is smaller in size and has a simpler structural design. It requires a smaller amount of gas for concentration detection. Depending on specific experimental needs, gas detection devices with different structural features can be used to measure the concentration of a single gas or a mixture of gases. Attached Figure Description

[0037] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0038] Figure 1 This is a schematic diagram of the gas detection device provided in the first embodiment of this application;

[0039] Figure 2 This is a schematic diagram of the gas detection device provided in the second embodiment of this application;

[0040] Figure 3 This is a schematic diagram of the gas detection device provided in the third embodiment of this application;

[0041] Figure 4 This is a schematic diagram of the gas detection device provided in the fourth embodiment of this application;

[0042] Figure 5 This is a schematic diagram of the gas detection device provided in the fifth embodiment of this application;

[0043] Figure 6 This is a flowchart of a gas concentration detection method provided in an embodiment of this application.

[0044] icon:

[0045] 1-Gas detection device; 100-Micro detection chamber; 110-Air inlet; 120-Independent detection unit; 200-Power source; 300-Air outlet; 400-Gas diffusion resistance component; 500-Working electrode; 600-Fixed volume micro gas chamber; 700-Micro reaction chamber. Detailed Implementation

[0046] The technical solutions in the embodiments of this application will now be described with reference to the accompanying drawings.

[0047] Similar reference numerals and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures. Furthermore, in the description of this application, terms such as "first," "second," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0048] The technical solution of this application will now be clearly and completely described with reference to the accompanying drawings.

[0049] Please refer to Figure 1 A gas detection device 1 includes: a micro-detection chamber 100, a power source 200, a gas diffusion resistance element 400, and a working electrode 500. The micro-detection chamber 100 has an air inlet 110, and the power source 200 is connected to the micro-detection chamber 100. An air outlet 300 is connected to the power source 200. The power source can be an air pump. The gas diffusion resistance element 400 is disposed within the micro-detection chamber 100, and the working electrode 500 is connected to the gas diffusion resistance element 400. The working electrode 500 is provided with a catalytic material for detecting the concentration response value of the gas to be tested and / or consuming the gas to be tested. While detecting the concentration of the gas to be tested, the working electrode 500 also consumes the gas to be tested, thereby causing a change in the gas concentration within the micro-detection chamber 100.

[0050] In one embodiment, please refer to Figure 2There is at least one gas diffusion resistance element 400 and at least one working electrode 500. For example, in this embodiment, three gas diffusion resistance elements 400 are provided in the micro-detection chamber 100, and a working electrode 500 is connected to each gas diffusion resistance element 400. The diffusion resistance of the three gas diffusion resistance elements 400 can be the same or different. The potentials of the gas diffusion resistance elements 400, the working electrode 500, and the catalytic material on the working electrode 500 are independent of each other. In the design, generally only one factor is changed. For example, when adjusting the gas diffusion resistance element 400, the potential of the working electrode 500 and the type of catalytic material do not change; when adjusting the potential of the working electrode 500, the gas diffusion resistance element 400 and the type of catalytic material do not change; or, when adjusting the type of catalytic material, the potential of the gas diffusion resistance element 400 and the working electrode 500 do not change. Of course, the above three factors can also be adjusted and changed simultaneously.

[0051] In one embodiment, please refer to Figure 3 The micro-detection chamber 100 contains at least one independent detection unit 120. Each independent detection unit 120 contains a gas diffusion resistance element 400 and a corresponding connected working electrode 500. Each independent detection unit 120 can detect different gases. In this embodiment, there are three independent detection units 120.

[0052] In one embodiment, such as Figure 3 As shown, taking three working electrodes 500 as an example, one of the three working electrodes 500 is a non-consumable detection electrode, that is, this working electrode 500 is only used to detect the change value of the concentration response of the gas to be measured, without consuming the gas to be measured. The other two working electrodes 500 are consumable detection electrodes, that is, these two working electrodes 500 are used to consume the specific gas to be measured, but are not used to detect the change value of the concentration response of the gas to be measured. This causes a certain component in the mixed gas to be consumed on these two working electrodes 500 at a certain reaction rate, thereby causing the gas concentration value of that component in the micro detection chamber 100 to change, and then the non-consumable detection electrode detects the change value of the gas concentration response of that component.

[0053] In one embodiment, please refer to Figure 4 The gas detection device 1 also includes a fixed-volume micro-gas chamber 600, which is connected in parallel with the micro-detection chamber 100 via a gas pipeline. In this embodiment, the micro-detection chamber 100 and the fixed-volume micro-gas chamber 600 are separated and combined into a circulating gas path using a power source 200. During measurement, the gas is driven to flow in the circulating gas path by a gas pump. The gas is consumed by the working electrode 500 within the gas detection device 1, resulting in a decrease in the gas concentration value. The current change pattern of the working electrode 500 is the same as that in the depletion-type working mode.

[0054] In one embodiment, please refer to Figure 5 The gas detection device 1 also includes a micro-reaction chamber 700; the micro-reaction chamber 700 is connected to a fixed-volume micro-gas chamber 600 and a power source 200 via pipelines. The micro-detection chamber 100, power source 200, and fixed-volume micro-gas chamber 600 form a circulating gas path. The micro-detection chamber 100 does not consume the gas being tested during the detection of its concentration; the gas concentration changes as the mixed gas passes through the micro-reaction chamber 700. Within the micro-reaction chamber 700, the rate of gas consumption is directly proportional to the gas concentration.

[0055] Please refer to Figure 6 This is a gas concentration detection method provided in one embodiment of the present application, which can be applied to... Figures 1-5 The gas detection device 1 shown is composed of a fixed-volume micro-detection chamber 100 and an electrochemical detection working electrode 500 placed in the micro-detection chamber 100. During detection, the working electrode 500 consumes the gas to be detected, causing a change in the gas concentration in the chamber. This change exhibits an exponential decay curve over a certain time range. The shape of the curve is related to the gas concentration, the volume of the chamber, the catalytic activity of the working electrode 500 on the gas, and the diffusion characteristics of the gas. By analyzing the obtained curve, the concentrations of various analytes in the mixed gas can be calculated. Based on the above principle, this method specifically includes steps S610-S630.

[0056] Step S610: Introduce the gas to be tested into the micro-detection chamber 100.

[0057] In this step, the gas to be tested can be introduced into the micro-detection chamber 100 through a sampling device (e.g., a syringe). The gas to be tested can be a single gas or a mixture of gases.

[0058] Step S620: Within the preset measurement time window, the working electrode 500 detects the response value of the gas to be measured.

[0059] In this step, the gas detection device 1 is always in working state when the working electrode 500 is detecting. During measurement, when the gas to be measured is introduced into the micro detection chamber 100, the response current value of the working electrode 500 is recorded throughout the preset measurement time window.

[0060] Step S630: Obtain the concentration of the gas to be tested based on the response value.

[0061] In one embodiment, when the detected gas is a single component and there are no interfering gases, the method is as follows: Figure 1 The gas detection device 1 shown is used to detect gas concentration. There is one working electrode 500 in the micro detection chamber 100.

[0062] When a single gas to be tested is introduced into the micro-detection chamber 100, the current value corresponding to the single gas to be tested detected by the working electrode 500 within the preset measurement time window is obtained; the current value is processed to obtain the response value of the single gas to be tested detected by the working electrode 500; and the concentration of the gas to be tested is obtained based on the response value.

[0063] The specific steps are as follows: Record the working electrode response curve throughout the preset measurement time window. Within the preset measurement time window, select two data analysis time windows, such as the first time window (from T-τ to T) and the second time window (from t...). i to t i+τ One or more gaseous components in the gas to be tested can react on the working electrode 500. The concentration of the gas to be tested can be calculated based on the difference in the response current value detected by the working electrode 500 within these two time windows. Under the condition that the volume of the micro-detection chamber 100 is fixed, the response current on the working electrode 500 generally satisfies the relationship formula (1):

[0064] I t =I0e -kt +I b (1)

[0065] Among them I t I0 is the response current at time t, and I0 is the initial reaction current, which is proportional to the concentration of the gas to be measured. b The baseline current of the working electrode 500 is given by k, which is a characteristic constant. Factors affecting its magnitude include the gas chamber volume, the catalytic activity of the working electrode 500 for the gas, and the diffusion characteristics of the gas.

[0066] At the end of the analysis period, select a time window (e.g., τ), and integrate the detected current signal within the first time window (from T-τ to T) (S). b Formula (2) is obtained. The purpose of selecting the time window τ to perform integration processing on the signal is to improve the signal-to-noise ratio.

[0067]

[0068] In the second time window of the analysis test (t i to t i +τ), integrate the current signal detected within the second time window to obtain formula (3).

[0069]

[0070] Formula (4) is obtained from (3)-(2):

[0071]

[0072] Where K is a characteristic constant, which can be defined as the response sensitivity of the working electrode 500 to the gas under the analytical conditions. Since K is a characteristic constant of the gas under the conditions of the gas detection device 1, the factors of its magnitude include the gas chamber volume, the catalytic reaction activity of the working electrode 500 to the gas, and the diffusion characteristics of the gas, and it is independent of the concentration of the gas to be measured. Therefore, under the condition of a fixed integration window, the value of the integral term in equation (4) is a constant and is independent of the gas concentration.

[0073] The sensitivity K in equation (4) can be pre-calibrated using a standard gas of known concentration. During measurement, equation (4) is used as the response equation to directly calculate the gas concentration, resulting in equation (5).

[0074]

[0075] The advantage of the gas concentration detection method in this embodiment is that the gas volume required for detection is small, and the interference of baseline current can be automatically deducted, thereby improving the selectivity and accuracy of the measurement results.

[0076] In one embodiment, when the detected gas is a single component and there are no interfering gases, the method is as follows: Figure 1 The gas detection device 1 shown performs gas concentration detection. There is one working electrode 500 in the micro detection chamber 100, and the detection is performed in a depletion mode.

[0077] When the micro-detection chamber 100 has a small volume, and an appropriate analysis period T is selected, at the end of this analysis period, if more than 99.9% of the gas to be measured can be consumed, the gas concentration can be directly measured using the following electrochemical analysis methods. Specifically, these include:

[0078] The electrical charge consumed by the zero-point gas (without the gas to be measured) detected by the working electrode 500 within a preset measurement time window is obtained as the first electrical charge value. For example, the zero-point gas (without the gas to be measured) is introduced into the micro-detection chamber, and the current is integrated within the measurement time window from 0 to T. The resulting electrical charge is recorded as Q0.

[0079] Within the same preset measurement time window, the amount of electricity consumed by the gas to be tested detected by the working electrode 500 is obtained as the second electricity value. For example, the gas to be tested is introduced into the micro-detection chamber, and the current signal is integrated within the range of 0 to T. The resulting electricity is recorded as Q.

[0080] The difference between the second charge value and the first charge value is used as the response value of the single gas to be tested detected by the working electrode 500, thus obtaining formula (6).

[0081]

[0082] Where: P - gas pressure in the microreaction chamber

[0083] V-microreaction chamber gas volume

[0084] T - Absolute temperature

[0085] R - gas constant

[0086] F-Faraday constant

[0087] N-reaction electron number

[0088] Q - Electricity consumed by the gas being tested

[0089] Q 0- Zero point gas consumption electricity

[0090] C-gas concentration

[0091] but

[0092] As can be seen from this equation, the response of the gas detection device 1 is independent of the catalytic activity of the working electrode 500, that is, the change in the electrocatalytic activity of the working electrode 500 has no effect on the measurement result. As long as the volume V of the micro-detection chamber 100 remains constant during its lifespan, the value in equation (7) is... It is a stability constant, which can be obtained by calculation or by calibration of a gas with a known concentration. The gas concentration C can be transformed into formula (8).

[0093] C = constant × (Q - Q0)T (8)

[0094] This is a highly stable measurement method that can directly measure the concentration of the gas to be measured even without knowing the sensitivity of the working electrode. Its disadvantage is that the time required to completely consume the gas to be measured may be relatively long.

[0095] In one embodiment, when the detected gas is a mixture and interfering gases are present, the method is adopted. Figure 1 The gas detection device 1 shown performs gas concentration detection. Based on the structure of the gas detection device 1, a gas filter device with at least two channels can be added. One channel is a direct gas path without filtration, while the other channel includes a filter material that can selectively and completely filter or filter the gas to be tested in a certain proportion. This filter material can be a chemical reaction reagent, an adsorbent, or a catalytic decomposition material. The micro-detection chamber 100 contains a single working electrode 500, which operates in a depletion-type mode for detection.

[0096] Specifically, the test gas mixture is introduced into the micro-detection chamber 100. Without any gas filtration device or filter material, the electrical charge value corresponding to the mixed gas detected by the working electrode 500 is recorded as electrical charge value one. When the micro-detection chamber 100 is equipped with a gas filtration device or filter material, the electrical charge value detected by the working electrode 500 as the mixed gas passes through the gas filtration device or filter material is recorded as electrical charge value two. The difference between electrical charge value one and electrical charge value two represents the electrical charge consumed for the complete reaction of the test gas within the micro-detection chamber 100. Based on the electrical charge value and the response value, the concentration of the test gas is obtained. Therefore, using the above method, the concentration of the test gas in a mixed gas can be detected.

[0097] In one embodiment, when the detected gas is a mixture, and at least two gas components, such as gas A and gas B, are measured, their reactions within the microdetection chamber 100 are independent and do not affect each other. Figure 1 The gas detection device 1 shown is used to detect gas concentration. There is one working electrode 500 in the micro detection chamber 100.

[0098] Obtain the charge value of the mixed gas detected by the working electrode 500 within the first preset sampling time window;

[0099] The charge value of the mixed gas detected by the working electrode 500 within the second preset sampling time window is obtained.

[0100] The charge value of the mixed gas detected by the working electrode 500 within the third preset sampling time window is obtained.

[0101] The specific steps are as follows: Record the response curve of the working electrode 500 throughout the determined analysis period (T). Under the condition that the volume of the micro-detection chamber 100 is fixed, the response current on the working electrode 500 generally satisfies the relationship, formula (9):

[0102]

[0103] Among them I t It is the response current at time t, I0 is the initial reaction current, which is proportional to the concentration of the gas to be measured, Ib is the baseline current of the working electrode 500, and k is a characteristic constant. Factors affecting its magnitude include the volume of the gas chamber, the catalytic activity of the working electrode 500 for the gas, and the diffusion characteristics of the gas. It is independent of the concentration of the gas to be measured.

[0104] At the end of the analysis period, select the first preset sampling time window (from T-τ to T), and integrate the current signal detected by the working electrode 500 between time T-τ and T to obtain formula (10) and formula (11).

[0105]

[0106] Select two time windows for any time period during the analysis and testing, such as the second preset sampling time window: (from t) i to t i +τ) and the third preset sampling time window (from t) j to t j +τ), respectively, integrate the current signals detected in the second preset sampling time window and the third preset sampling time window to obtain formula (11) and formula (12).

[0107]

[0108]

[0109] From (11)-(10) and (12)-(10), we get formulas (13) and (14).

[0110]

[0111]

[0112] in The characteristic constant can be defined as follows: under the analytical conditions (corresponding to the integration interval (t)). i , t i +τ) and (t) j ,t j The working electrode at +τ)) 500° provides the response sensitivity of the test gas A and gas B. This sensitivity can be obtained by calibration using a standard gas of known concentration. Because The system of equations (13) and (14) has a unique solution, from which the concentrations of gas A and gas B can be calculated.

[0113] By taking different integration intervals, theoretically, countless independent equations can be written. As long as the response sensitivity of the gas corresponding to each independent integration interval is known (and can be calibrated), theoretically, a single response curve can analytically calculate the concentration of all reactive gases in the gas mixture. Of course, the differences in response sensitivity of each gas should be distinguishable.

[0114] In one embodiment, when the gas being detected is a mixture and at least two gas components are measured, there are multiple working electrodes 500 within the microdetection chamber 100.

[0115] For example, using Figure 2The gas detection device 1 shown has three working electrodes 500 within the micro-detection chamber 100, each using a different electrode catalytic material. Alternatively, each working electrode 500 may use the same electrode catalytic material, but with different diffusion channel resistances in contact with the gas. Or, each working electrode 500 may use the same electrode catalytic material, but with different electrode potentials controlled by the working electrodes.

[0116] In one embodiment, when the gas being detected is a mixture and at least two gas components are measured, the micro-detection chamber 100 is provided with three independent detection units 120, and each independent detection unit 120 is provided with a working electrode 500.

[0117] The gas detection device 1 of this application is small in size and has a simple structural design. It requires a small amount of gas for concentration detection. Depending on specific experimental needs, gas detection devices 1 with different structural features can be used to measure the concentration of a single gas or a mixture of gases.

[0118] It should be noted that, where there is no conflict, the features in the embodiments of this application can be combined with each other.

[0119] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A method for detecting gas concentration, characterized in that, This method utilizes a gas detection device, which includes: a micro-detection chamber with a fixed volume and an air inlet; a power source connected to the micro-detection chamber; an air outlet connected to the power source; and at least one independent detection unit disposed within the micro-detection chamber. Each independent detection unit includes a gas diffusion resistance element disposed within the micro-detection chamber; and a working electrode connected to the gas diffusion resistance element, the working electrode having a catalytic material for detecting the concentration response value of the analyte gas and / or consuming the analyte gas. The method includes: The gas to be tested is introduced into the micro-detection chamber; Within a preset measurement time window, the working electrode detects the response value of the gas to be measured; Based on the response value, the response curve of the working electrode and the concentration of the gas to be tested are obtained.

2. The gas concentration detection method according to claim 1, characterized in that, The working electrode is either a consumable detection electrode or a non-consumable detection electrode.

3. The gas concentration detection method according to claim 1, characterized in that, The power source is an air pump.

4. The gas concentration detection method according to claim 1, characterized in that, Within a preset measurement time window, the working electrode detects the response value of the gas to be measured, including: When a single gas to be tested is introduced into the micro-detection chamber, the current value corresponding to the single gas to be tested detected by the working electrode within a preset measurement time window is obtained. The current value is processed to obtain the response value of the single gas to be tested detected by the working electrode.

5. The gas concentration detection method according to claim 1, characterized in that, Within a preset measurement time window, the working electrode detects the response value of the gas to be measured, including: The electrical charge value of the zero-point gas (excluding the gas to be measured) detected by the working electrode within the preset measurement time window is obtained as the first electrical charge value. Within the same preset measurement time window, the amount of electricity consumed by the gas to be measured detected by the working electrode is obtained as the second amount of electricity. The difference between the second charge value and the first charge value is processed to obtain the response value of the single gas to be tested detected by the working electrode.

6. The gas concentration detection method according to claim 1, characterized in that, Within a preset measurement time window, the working electrode detects the response value of the gas to be measured, including: When the mixed gas to be tested is introduced into the micro detection chamber and there is no gas filter in the micro detection chamber, the electrical charge value corresponding to the mixed gas detected by the working electrode is obtained as the electrical charge value one. When a gas filtration device is present in the micro-detection chamber, the electrical charge value of the mixed gas to be tested detected by the working electrode is obtained as the second electrical charge value. The difference between the second electrical charge value and the first electrical charge value is processed to obtain the response value of the gas to be tested after complete reaction in the micro-detection chamber.

7. The gas concentration detection method according to claim 1, characterized in that, Within a preset measurement time window, the working electrode detects the response value of the gas to be measured, including: The gas mixture to be tested is introduced into the micro-detection chamber; Obtain the charge value of the mixed gas detected by the working electrode within the first preset sampling time window; Obtain the charge value of the mixed gas detected by the working electrode within the second preset sampling time window; Obtain the charge value of the mixed gas detected by the working electrode within the third preset sampling time window; Based on the charge value of the mixed gas within the first preset sampling time window, the charge value of the mixed gas within the second preset sampling time window, and the charge value of the mixed gas within the third preset sampling time window, the response values ​​of different gas components in the mixed gas are obtained.

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