Gas analysis device and method for detecting a sample gas

Abstract

Provided are a gas analysis device and a method for detecting a sample gas. The gas analysis device includes: an ion mobility spectrometer, which includes an ion mobility tube, an ion gate, a plurality of electrodes, a suppression grid, and a Faraday disk that are sequentially arranged in the ion mobility tube, and the Faraday disk is adapted to receive sample ions discharged from the suppression grid, and a through hole is provided on the Faraday disk; a mass spectrometer; a gate valve provided between the Faraday disk and an ion inlet of the mass spectrometer; and a controller adapted to control the opening or closing of the gate valve to allow the sample ions discharged from the suppression grid to flow into the mass spectrometer through the through hole of the Faraday disk when the gate is opened. By using the gas analysis device and the method for detecting a sample gas, the combined use of a portable ion mobility drift-ion trap mass spectrometer can be realized, and according to the actual situation, a single detection mode or a plurality of mixed detection modes can be selected.

Description

Technical Field

[0001] Embodiments of the present disclosure relate to a gas analysis device, and particularly to a gas analysis device for detecting gases in multiple ways and a method for detecting a sample gas. Background Art

[0002] Currently, a gas analysis device based on the technology of cluster gas chromatography tandem ion mobility spectrometry can basically meet the requirements of the customs for the rapid non-opening inspection of animals, plants, and foods at the passenger inspection and cargo inspection channels. In such a gas analysis device, through the preliminary separation by chromatography and then the secondary separation by the ion mobility system, two-dimensional data composed of the retention time and the migration time of the analyte will be obtained. Since the polarities of different substances and the cross-sectional areas of ion collisions are not the same, a good distinction can be achieved.

[0003] However, in the above gas analysis device, a time-of-flight mass analyzer with an extremely fast scanning speed is used. This mass analyzer is large in volume and complex in control system. Although it can complete the acquisition of all mass spectrometry data in a single scan of the ion mobility system, due to the limitations of the volume and the complexity of the control system, it cannot be miniaturized. And the detection speed of a miniaturized mass spectrometer is slow, and it cannot be fully synchronized with the ion mobility spectrometry analysis, so a complete ion mobility spectrometry-mass spectrometry combined spectrum cannot be obtained. Summary of the Invention

[0004] The purpose of the present disclosure is to solve at least one of the above problems and defects existing in the prior art.

[0005] According to an embodiment of one aspect of the present disclosure, there is provided a gas analysis device, including: an ion mobility spectrometer, including an ion mobility tube, an ion gate, a plurality of electrodes, a suppression grid, and a Faraday disk that are sequentially arranged in the ion mobility tube, and the Faraday disk is adapted to receive sample ions discharged from the suppression grid, and the Faraday disk is provided with a through hole; a mass spectrometer; a gate valve, arranged between the Faraday disk and the ion inlet of the mass spectrometer; and a controller, adapted to control the opening or closing of the gate valve to allow the sample ions discharged from the suppression grid to flow into the mass spectrometer through the through hole of the Faraday disk when the gate is opened.

[0006] According to an embodiment of the present disclosure, the controller is further adapted to control the voltages applied to the ion gate, the electrodes, and the suppression grid and the startup of the mass spectrometer to control the working mode of the ion mobility spectrometer.

[0007] According to an embodiment of the present disclosure, the controller is adapted to control the ion gate to open or close alternately, and control the voltages applied to the electrode and the suppression grid so that sample ions move from the ion gate through the suppression grid and migrate to the Faraday disk, and control the gate to close, so that the gas analysis device operates in the ion mobility spectrometry detection mode.

[0008] According to an embodiment of the present disclosure, the controller is adapted to control the ion gate and the suppression grid to be in a continuous open state and control the gate valve to open, so that sample ions move from the ion gate through the through-hole of the Faraday disk and enter the mass spectrometer, so that the gas analysis device operates in the mass spectrometry detection mode.

[0009] According to an embodiment of the present disclosure, the controller is adapted to control the ion gate to open or close alternately, and control the voltages applied to the electrode and the suppression grid so that sample ions move from the ion gate through the suppression grid and migrate to the Faraday disk, and control the gate valve to open or close alternately, so as to allow the sample ions to pass through the through-hole of the Faraday disk and enter the mass spectrometer after collecting signals from the Faraday disk, so that the gas analysis device operates in a first hybrid detection mode including the ion mobility spectrometry detection mode and the mass spectrometry detection mode.

[0010] According to an embodiment of the present disclosure, the controller is adapted to control the ion gate to open or close alternately, and control the voltages applied to the electrode and the suppression grid so that sample ions move from the ion gate through the suppression grid and migrate to the Faraday disk, and control the suppression grid to open or close alternately, so as to selectively release some of the sample ions through the Faraday disk and enter the mass spectrometer while collecting signals from the Faraday disk, so that the gas analysis device operates in a second hybrid detection mode including the ion mobility spectrometry detection mode and the mass spectrometry detection mode.

[0011] According to an embodiment of the present disclosure, the controller is adapted to control the ion gate to open or close alternately, and control the voltages applied to the electrode and the suppression grid so that sample ions move from the ion gate through the suppression grid and migrate to the Faraday disk, and control the gate valve to open, so that the sample ions enter the mass spectrometer through the through-hole of the Faraday disk at multiple ion selection time sequences, so that the gas analysis device operates in the mass spectrometer enrichment detection mode for detecting multiple ion beams of a single accumulated sample.

[0012] According to an embodiment of the present disclosure, the gas analysis device further includes a signal acquisition device, and the signal acquisition device obtains a migration spectrogram and a mass spectrogram based on the sample ions received by the Faraday disk and the sample ions entering the mass spectrometer.

[0013] According to an embodiment of the present disclosure, the ion mobility spectrometer further includes: an ion source adapted to generate initial charged ions; a sample inlet for delivering a sample gas into the ion migration tube; and an isolation grid disposed between the ion source and the ion gate to form a charge exchange region between the ion source and the isolation grid and an ion enrichment chamber between the isolation grid and the ion gate.

[0014] According to an embodiment of the present disclosure, the ion migration tube is provided with a migration gas inlet downstream of the suppression grid and a migration gas outlet upstream of the ion gate.

[0015] According to an embodiment of the present disclosure, each of the ion gate and the suppression grid includes a frame and a metal mesh connected to the frame.

[0016] According to an embodiment of the present disclosure, the mass spectrometer includes: an ion focusing device adapted to receive sample ions from the Faraday disk; a vacuum chamber provided with an ion trap adapted to receive the sample ions from the ion focusing device and an ion detector for generating a mass spectrum based on the ions collected in the ion trap; and a vacuum device adapted to evacuate the vacuum chamber to a vacuum such that the sample ions move to the ion trap.

[0017] According to an embodiment of the present disclosure, the mass spectrometer further includes: a pre-vacuum chamber disposed between the ion focusing device and the vacuum chamber; a transfer device disposed in the pre-vacuum chamber to transfer the sample ions of the ion focusing device to the ion trap; and a pre-vacuum device adapted to evacuate the pre-vacuum chamber to a vacuum such that the sample ions move from the ion focusing device to the transfer device.

[0018] According to an embodiment of the present disclosure, the mass spectrometer further includes a vacuum exhaust port adapted to adjust the air pressure in the pre-vacuum chamber and the vacuum chamber.

[0019] According to an embodiment of another aspect of the present disclosure, there is provided a method for detecting a sample gas using the automatic sampling device according to any one of the above embodiments, including the following steps: inputting the sample gas into the ion mobility spectrometer; controlling the opening or closing of the gate valve to allow the sample ions discharged from the suppression grid of the ion mobility spectrometer to flow through the through hole of the Faraday disk into the mass spectrometer when the gate is opened.

[0020] According to an embodiment of the present disclosure, the voltages applied to the ion gate, the electrodes, and the suppression grid of the ion mobility spectrometer are controlled to control the working mode of the ion mobility spectrometer.

[0021] According to an embodiment of the present disclosure, the steps of controlling the voltages applied to the ion gate, electrodes, and suppression grid of an ion mobility spectrometer include: controlling the ion gate to open or close alternately; controlling the voltages applied to the electrodes and suppression grid such that sample ions move from the ion gate through the suppression grid and migrate to the Faraday disk; and controlling the gate valve to close, so that the gas analysis device operates in an ion mobility spectrometry detection mode.

[0022] According to an embodiment of the present disclosure, the steps of controlling the voltages applied to the ion gate, electrodes, and suppression grid of an ion mobility spectrometer include: controlling the ion gate and the suppression grid to be in a continuous open state; controlling the gate valve to open, such that sample ions move from the ion gate through the through-hole of the Faraday disk and enter the mass spectrometer, so that the gas analysis device operates in a mass spectrometry detection mode.

[0023] According to an embodiment of the present disclosure, the steps of controlling the voltages applied to the ion gate, electrodes, and suppression grid of an ion mobility spectrometer include: controlling the ion gate to open or close alternately; controlling the voltages applied to the electrodes and suppression grid such that sample ions move from the ion gate through the suppression grid and migrate to the Faraday disk; and controlling the gate valve to open or close alternately to allow the sample ions to pass through the through-hole of the Faraday disk and enter the mass spectrometer after collecting signals from the Faraday disk, so that the gas analysis device operates in a first hybrid detection mode including an ion mobility spectrometry detection mode and a mass spectrometry detection mode.

[0024] According to an embodiment of the present disclosure, the steps of controlling the voltages applied to the ion gate, electrodes, and suppression grid of an ion mobility spectrometer include: controlling the ion gate to open or close alternately; controlling the voltages applied to the electrodes and suppression grid such that sample ions move from the ion gate through the suppression grid and migrate to the Faraday disk; and controlling the suppression grid to open or close alternately to selectively release some of the sample ions through the Faraday disk and into the mass spectrometer while collecting signals from the Faraday disk, so that the gas analysis device operates in a second hybrid detection mode including an ion mobility spectrometry detection mode and a mass spectrometry detection mode.

[0025] According to an embodiment of the present disclosure, the steps of controlling the voltages applied to the ion gate, electrodes, and suppression grid of an ion mobility spectrometer include: controlling the ion gate to open or close alternately; controlling the voltages applied to the electrodes and suppression grid such that sample ions move from the ion gate through the suppression grid and migrate to the Faraday disk; and controlling the gate valve to open, such that the sample ions enter the mass spectrometer through the Faraday disk at multiple ion selection time sequences, and the gas analysis device operates in a mass spectrometer enrichment detection mode for detecting multiple ion streams of a single accumulated sample. Description of the Drawings

[0026] Figure 1 Shows a schematic diagram of a gas analysis device according to an exemplary embodiment;

[0027] Figure 2 Shows a schematic diagram of a Faraday disk according to an exemplary embodiment of the present disclosure;

[0028] Figure 3 Shows a schematic diagram of an ion gate according to an exemplary embodiment of the present disclosure;

[0029] Figure 4 Shows a schematic diagram of an electrode according to an exemplary embodiment of the present disclosure;

[0030] Figure 5 Shows a timing diagram when the gas analysis device according to an exemplary embodiment of the present disclosure is used as an ion mobility spectrometer;

[0031] Figure 6 Shows a timing diagram when the gas analysis device according to an exemplary embodiment of the present disclosure is used as a mass spectrometer;

[0032] Figure 7 Shows a first mixing timing diagram when the gas analysis device according to an exemplary embodiment of the present disclosure is operating in the first mixing detection mode;

[0033] Figure 8 Shows a schematic diagram of the principle of orthogonal processing of one migration spectrum and multiple mass spectra to obtain a composite spectrum in the first mixing detection mode;

[0034] Figure 9 Shows a second mixing timing diagram obtained when the gas analysis device according to an exemplary embodiment of the present disclosure is operating in the second mixing detection mode;

[0035] Figure 10 Shows a schematic diagram of the principle of orthogonal processing of each corresponding migration spectrum and mass spectrum at one time point to obtain a composite spectrum in the second mixing detection mode; and

[0036] Figure 11 Shows an enrichment timing diagram when the gas analysis device according to an exemplary embodiment of the present disclosure is operating in the mass spectrometer accumulation detection mode. Detailed Description of the Invention

[0037] The following will clearly and completely describe the technical solutions in the embodiments of the present disclosure with reference to the accompanying drawings in the embodiments of the present disclosure. Obviously, the described embodiments are only a part rather than all of the embodiments of the present disclosure. The following description of at least one exemplary embodiment is merely illustrative and in no way limits the present disclosure or its application or use. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present disclosure without creative efforts fall within the scope of protection of the present disclosure.

[0038] In the following detailed description, for the sake of explanation, numerous specific details are set forth in order to provide a thorough understanding of the embodiments of the present disclosure. However, it is obvious that one or more embodiments may be implemented without these specific details. In other instances, well-known structures and devices are shown in diagrammatic form to simplify the drawings. Technologies, methods, and devices known to those of ordinary skill in the relevant art may not be discussed in detail, but where appropriate, the said technologies, methods, and devices should be regarded as part of the authorized specification.

[0039] In the description of the present disclosure, it should be understood that the use of terms such as "first" and "second" to define components is only for the convenience of differentiating the corresponding components. Without further statement, the above terms have no special meaning and thus should not be construed as limiting the scope of protection of the present disclosure.

[0040] According to an overall inventive concept of the present disclosure, there is provided a gas analysis device, including: an ion mobility spectrometer, including an ion mobility tube, an ion gate, a plurality of electrodes, a suppression grid, and a Faraday disk that are sequentially arranged in the ion mobility tube, the Faraday disk being adapted to receive sample ions discharged from the suppression grid, and having a through hole thereon; a mass spectrometer; a gate valve disposed between the Faraday disk and the ion inlet of the mass spectrometer; and a controller adapted to control the opening or closing of the gate to allow the sample ions discharged from the suppression grid to flow through the through hole of the Faraday disk into the mass spectrometer when the gate is opened.

[0041] According to another overall inventive concept of the present disclosure, there is provided a method for detecting a sample gas using the above automatic sampling device, including the following steps: inputting the sample gas into the ion mobility spectrometer; controlling the opening or closing of the gate valve and the suppression grid to allow the sample ions discharged from the suppression grid of the ion mobility spectrometer to flow through the through hole of the Faraday disk into the mass spectrometer when the gate valve and the suppression grid are both opened.

[0042] According to an embodiment of the present disclosure, there is provided a gas analysis device suitable for detecting hazardous substances.

[0043] Figure 1Shows a schematic diagram of a gas analysis device according to an exemplary embodiment.

[0044] As Figure 1 shown, in one embodiment, the gas analysis device 100 includes an Ion Mobility Spectrometry (IMS) 1, a mass spectrometer 2, a gate valve 3, and a controller 4. The ion mobility spectrometer 1 includes an ion mobility tube 11, an ion gate 12, a plurality of electrodes 13, a suppression grid 14, and a Faraday disk 15 that are sequentially arranged in the ion mobility tube. The Faraday disk 15 is adapted to receive sample ions discharged from the suppression grid 14.

[0045] Figure 2 Shows a schematic diagram of a Faraday disk according to an exemplary embodiment of the present disclosure; Figure 3 Shows a schematic diagram of an ion gate according to an exemplary embodiment of the present disclosure; Figure 4 Shows a schematic diagram of an electrode according to an exemplary embodiment of the present disclosure.

[0046] In an exemplary embodiment, as Figure 2 shown, through holes 151 are provided on the Faraday disk 15 to allow part of the sample ions discharged from the suppression grid 14 to pass through the through holes 151. As Figure 3 shown, each of the ion gate 12 and the suppression grid 14 includes a frame 121 and a metal mesh 122 connected to the frame. As Figure 4 shown, each electrode 13 is arranged in a circular ring shape. A plurality of electrodes 13 and the suppression grid 14 form an electric field gradient in the migration tube 11 to move charged sample ions in the migration chamber 111 of the migration tube 11. It can be understood that by changing the potential difference between the electrode 13 and the suppression grid 14, the migration speed of the sample ions in the migration tube 11 can be changed.

[0047] In an exemplary embodiment, referring to Figure 1 , the ion mobility spectrometer 1 further includes: an ion source 16 adapted to generate initial charged ions; a sample input port 17 for delivering the sample gas to be detected into the ion mobility tube 11; and an isolation grid 18, such as a honeycomb-shaped gold-plated steel mesh, provided between the ion source 16 and the ion gate 12. A charge exchange region 181 is formed between the ion source 16 and the isolation grid 18. The sample gas input from the sample input port 17 exchanges charges with the charged ions generated by the ion source 16 in the charge exchange region 181, so that the sample gas is ionized to generate sample ions. An ion enrichment chamber 182 is formed between the isolation grid and the ion gate. An electric field is formed between the isolation grid 18 and the ion gate 12, and gaseous sample ions can freely diffuse from the charge exchange region 181 to the ion enrichment chamber 182, and the sample ions are enriched or temporarily stored in the ion enrichment chamber 182.

[0048] In an exemplary embodiment, refer to Figure 1 , the ion migration tube 11 is provided with a migration gas inlet 112 downstream of the suppression grid 14 and a migration gas outlet 113 upstream of the ion gate 12. There is a pressure difference between the migration gas outlet 113 and the migration gas inlet 112 to form a migration gas flow in the migration tube 11.

[0049] In an exemplary embodiment, refer to Figure 1 , the mass spectrometer 2 includes an ion focusing device 21, a vacuum chamber 22, and a vacuum device 23. The ion focusing device 21 is adapted to receive sample ions from the Faraday disk 15; an ion trap for receiving sample ions from the ion focusing device 21 and an ion detector for generating a mass spectrum based on the ions collected in the ion trap are provided in the vacuum chamber 22. The vacuum device 23 is adapted to evacuate the vacuum chamber to a vacuum so that the sample ions move to the ion trap.

[0050] In an exemplary embodiment, the mass spectrometer 2 further includes: a pre-vacuum chamber 24, a transfer device 25, and a pre-vacuum device 26. The pre-vacuum chamber 24 is disposed between the ion focusing device 21 and the vacuum chamber 22. The transfer device 25 is disposed in the pre-vacuum chamber 25 to transfer the sample ions of the ion focusing device to the ion trap. The pre-vacuum device 26 is adapted to evacuate the pre-vacuum chamber 25 to a vacuum so that the sample ions move from the ion focusing device 21 to the transfer device 25. For example, the pre-vacuum device 26 includes a mechanical pump.

[0051] In an exemplary embodiment, the mass spectrometer 2 further includes a vacuum exhaust port 27 adapted to adjust the air pressure in the pre-vacuum chamber 26 and the vacuum chamber 22. For example, the vacuum exhaust port 27 can be connected to a turbopump, and the operation of the turbopump can create a vacuum in the pre-vacuum chamber 26 and the vacuum chamber 22 that satisfies mass analysis.

[0052] In an exemplary embodiment, refer to Figure 1 , the gas analysis device 100 further includes a signal acquisition device, and the signal acquisition device obtains a migration spectrum and a mass spectrum based on the sample ions received by the Faraday disk 15 and the sample ions entering the mass spectrometer 2.

[0053] In an exemplary embodiment, as Figures 1 - 4As shown, the gate valve 3 is disposed between the Faraday disk 15 and the ion inlet of the mass spectrometer 2. The controller 4 is adapted to control the opening or closing of the gate valve 3 to allow sample ions discharged from the suppression grid 14 to flow into the mass spectrometer 2 through the through hole 151 of the Faraday disk 15 when the gate valve 3 is open. The mass spectrometer 2 can detect the incoming sample ions and display a mass spectrum through a signal acquisition device.

[0054] In one exemplary embodiment, the controller 4 is further adapted to control the voltages applied to the ion gate 12, the electrode 13, and the suppression grid 14 and the startup of the mass spectrometer to control the working mode of the ion mobility spectrometer 1.

[0055] Figure 5 The timing schematic diagram when an exemplary embodiment gas analysis device of the present disclosure is used as an ion mobility spectrometer is shown.

[0056] In one exemplary embodiment, referring to Figure 1 and 5 , the controller 4 is adapted to alternately control the opening or closing of the ion gate 12 and control the voltages applied to the electrode 13 and the suppression grid 14 so that the sample ions move from the ion gate 12 through the suppression grid 14 to the Faraday disk 15. The Faraday disk 15 receives the sample ions and generates a signal, and through migration spectrum scanning, a migration spectrum is displayed on the signal acquisition device. During this process, the gate valve 3 is controlled to be closed, and the sample ions cannot reach the mass spectrometer 2, so that the gas analysis device 100 operates in the ion mobility spectrometry detection mode. The ion mobility spectrometry detection mode has a short analysis cycle and a high frequency, and can be adapted to the detection work after the chromatographic column.

[0057] Figure 6 The timing schematic diagram when an exemplary embodiment gas analysis device of the present disclosure is used as a mass spectrometer is shown.

[0058] In one exemplary embodiment, referring to Figure 1 and 6 , the controller 3 is adapted to control the ion gate 12 and the suppression grid 14 to be in a continuous open state and control the gate valve 3 to be open, so that the sample ions move from the ion gate 12 through the through hole 151 of the Faraday disk 15 into the mass spectrometer 2, so that the gas analysis device operates in the mass spectrometry detection mode, and through mass spectrometry scanning, a series of spectra at different times are displayed on the signal acquisition device, and the timing schematic diagram is as Figure 6 shown.

[0059] Figure 7 The first mixed detection mode timing schematic diagram obtained when an exemplary embodiment gas analysis device of the present disclosure operates in the first mixed detection mode is shown.

[0060] In one exemplary embodiment, referring to Figure 1 and 7 , the controller 3 is adapted to control the ion gate 12 to open or close alternately, and control the voltages applied to the electrode 13 and the suppression grid 14 such that sample ions move from the ion gate 12 through the downstream suppression grid 14 to the Faraday disk 15, so as to obtain an ion mobility signal from the Faraday disk 15; thereafter, the signal acquisition device stops acquiring signals from the Faraday disk, and controls the gate valve 3 to open or close alternately, so as to allow the sample ions to alternately enter the mass spectrometer through the through hole 151 of the Faraday disk 15 and obtain a plurality of mass spectra distributed at intervals on the signal acquisition device, thereby enabling the gas analysis device to operate in a first hybrid detection mode including an ion mobility spectrometry detection mode and a mass spectrometry detection mode. In the first hybrid detection mode, the signal acquisition device outputs a mobility spectrum, and then alternately outputs a plurality of mass spectra at intervals of a predetermined time, and subsequent data processing is performed by the supporting computer software, which is equivalent to the serial operation of an ion mobility spectrometer and a mass spectrometer.

[0061] Specifically, referring to Figure 7, under the control of the controller 4, the suppression grid 14 is opened, the ion gate 12 is opened for a predetermined time, the gate valve 3 is closed, the Faraday disk 15 receives sample ions and generates a signal, and the signal acquisition device obtains a migration spectrum from the Faraday disk; thereafter, the suppression grid 14 is closed, the Faraday disk 15 stops collecting sample ions, and the acquisition of the migration spectrum is completed; thereafter, the ion gate 12 continues to be opened for a predetermined time, and the gate valve 3 is opened. During this period, since the suppression grid 14 is still in the closed state, the sample ions cannot enter the mass spectrometer; thereafter, the controller controls the suppression grid 14 to be opened within a predetermined time period to allow the sample ions corresponding to some peak signals to enter the mass spectrometer. However, during the entry of the sample ions into the mass spectrometer, no mass spectrum is still displayed on the signal acquisition device, thereby forming an ion selection timing located before the mass spectrometry timing as shown in FIG. 7; thereafter, the sample ions completely enter the mass spectrometer under the action of the vacuum device 26, and multiple spaced mass spectra are obtained on the signal acquisition device. That is to say, before each mass spectrometry timing, there is an ion selection timing in which the sample ions move from the Faraday disk 15 to the mass spectrometer 2 when the gate valve 3 is controlled by the controller to be opened, which represents the time when the sample ions move from the Faraday disk 15 to the ion detector of the mass spectrometer 2. In the first hybrid detection mode, the migration spectrum peak position (the opening time point of the suppression grid 14) and the peak width (the opening duration of the suppression grid 14) that need to be scanned by the mass spectrometer 2 can be determined by the pre-programmed software algorithm of the gas analysis device, or the suppression grid 14 is controlled by the controller 4 to be opened in multiple subsequent ion mobility scans according to the pre-programmed migration time and peak width. When scanning the mass spectrometer 2, the controller 4 opens the gate valve 3 and inhales the sample ions passing through the through hole 151 of the Faraday disk 15 into the ion focusing device 21 of the mass spectrometer 2. After the sample ions are enriched by the ion focusing device 21, they are then inhaled into the vacuum chamber 22 for detection. In the subsequent detection of the ion mobility spectrometer, each mass spectrometry scan is accompanied by a mass spectrometry scan of the corresponding migration spectrum peak position, and the data is spliced by software to obtain a migration spectrum-mass spectrum including one migration spectrum and multiple mass spectra. Since the whole machine of the gas analysis device 100 uses continuous sampling and the sample retention in the environment is large, each migration spectrum can be regarded as the same sample, and the first migration spectrum can be used to represent all the migration spectra. The gate valve 3 remains open during the migration spectrum scan to ensure the gas flow consistency during the migration spectrum scan and the subsequent migration spectra as the primary ions are spaced apart.

[0062] Airflow consistency when the selector.

[0063] Figure 8 FIG. shows a schematic principle diagram of obtaining a composite spectrum by orthogonally processing one migration spectrum and multiple mass spectra in the first hybrid detection mode.

[0064] In one exemplary embodiment, refer to Figure 7 and8 The signals of a mobility spectrum scan and multiple mass spectrum scans are orthogonally processed by a pre-programmed software algorithm of the gas analysis device. The signal intensities at corresponding positions can be orthogonally multiplied, and a non-zero composite signal is obtained only when the signals of the mobility spectrum scan and multiple mass spectrum scans are both non-zero. Moreover, only when the peak positions of the mobility spectrum scan signal and the mass spectrum scan signal appear simultaneously will they be marked as composite peaks. Finally, an orthogonal composite spectrogram in the first hybrid detection mode is obtained. Assuming that each substance has only one signal peak, three substances generate three signals represented by the processed peak positions.

[0065] Figure 9 Fig. shows a second hybrid timing schematic diagram obtained when a gas analysis device according to an exemplary embodiment of the present disclosure operates in the second hybrid detection mode.

[0066] In an exemplary embodiment, referring to Figure 1 and 9 , the controller 3 is adapted to control the ion gate 12 to open, and control the voltages applied to the electrode 13 and the suppression grid 14 so that the sample ions move from the ion gate 12 through the downstream suppression grid 14 to the Faraday disk 15. At the same time, control the gate valve 3 to open, and control the suppression grid to alternately open or close, so that the suppression grid selectively releases part of the sample ions from the ion gate, and the gate valve 3 selectively allows the sample ions that have passed through the suppression grid to pass through the through hole 151 of the Faraday disk 15 and enter the mass spectrometer 2, thereby enabling the gas analysis device to operate in a second hybrid detection mode including an ion mobility spectrometry detection mode and a mass spectrometry detection mode. In the second hybrid detection mode, the signal acquisition device always maintains the output of the mobility spectrogram of the sample and alternately outputs the mass spectrogram, and subsequent data processing is performed by the supporting computer software. In the second hybrid detection mode, the signal acquisition device always maintains the output of a mobility spectrogram, and alternately outputs multiple mass spectrograms at intervals of a predetermined time, and subsequent data processing is performed by the supporting computer software, which is equivalent to the parallel operation of an ion mobility spectrometer and a mass spectrometer.

[0067] Specifically, referring to Figure 9 , under the control of the controller 4, the suppression grid 14 is opened, the ion gate 12 is opened for a predetermined time, the gate valve 3 is closed, the Faraday disk 15 receives the sample ions and generates a signal, and the signal acquisition device always maintains obtaining the mobility spectrogram from the Faraday disk; thereafter, the ion gate 12 continues to be opened for a predetermined time, the gate valve 3 is opened, and the suppression grid 14 is controlled to alternately open or close to allow part of the sample ions corresponding to the peak signals to enter the mass spectrometer. However, during the period when the sample ions enter the mass spectrometer, no mass spectrogram is still displayed on the signal acquisition device, thereby forming Figure 9The ion selection timing between the migration spectrum timing and the mass spectrum timing shown; thereafter, the sample ions completely enter the mass spectrometer under the action of the vacuum device 26, and a plurality of mass spectra distributed at intervals are obtained on the signal acquisition device. That is to say, since the signal acquisition device keeps obtaining the migration spectrum from the Faraday disk, before each mass spectrum timing, there is an ion selection timing when the sample ions move from the Faraday disk 15 to the mass spectrometer 2 when the gate valve 3 is opened under the control of the controller, which represents the time interval for the sample ions to move from the Faraday disk 15 to the ion detector of the mass spectrometer 2.

[0068] Figure 10 The schematic diagram of the principle of obtaining the composite spectrum by orthogonally processing each corresponding migration spectrum and mass spectrum at one time point in the second hybrid detection mode is shown.

[0069] In an exemplary embodiment, refer to Figure 9 and 10 , the orthogonal processing is performed on the signal of one migration spectrum scan and the signals of multiple mass spectrum scans by the pre-programmed software algorithm of the gas analysis device. The signal intensities at the corresponding positions can be orthogonally multiplied. Only when the signals of both the migration spectrum scan and the multiple mass spectrum scans are not zero, a non-zero composite signal can be obtained. And only when the peak positions of the migration spectrum scan signal and the mass spectrum scan signal appear simultaneously will they be marked as composite peaks. Finally, three orthogonal composite spectra in the second hybrid detection mode are obtained at three injection time points. Suppose there are three substances, and each substance has only one signal peak. Since there is no suppression grid involved in the selection of the signals entering the mass spectrometer, multiple peaks will be generated. Then, at each time point, 9 signals represented by the processed peak positions are generated for the three substances after orthogonal processing.

[0070] Figure 11 The schematic diagram of the enrichment timing when the gas analysis device of an exemplary embodiment of the present disclosure works in the mass spectrometer cumulative detection mode is shown.

[0071] In an exemplary embodiment, refer to Figure 1 and 11, the controller 4 is adapted to control the ion gate 12 to open or close alternately, and control the voltages applied to the electrode 13 and the suppression grid 14 so that the sample ions move from the ion gate 12 through the suppression grid 14 to the Faraday disk 15, and control the gate valve 3 to open or close alternately, so that the gate valve 3 selectively allows the sample ions to enter the mass spectrometer 2 through the through hole 151 of the Faraday disk 15 in multiple ion selection time sequences, so that the gas analysis device 100 operates in a mass spectrometer enrichment detection mode capable of detecting multiple ions of a single accumulated sample. Since the sample ion injection time of a single ion trap of the mass spectrometer allows to be greater than the time of multiple scans of the ion mobility spectrometer, it means that multiple (for example, 6 times or 7 times) screening of sample ions can be performed, and the screened sample ions are injected into the ion trap in a multiple accumulation manner. As the amount of ions increases, the mass spectrometry signal is enhanced. Figure 11 An example of 7 cumulative injections and one mass spectrometry detection is shown.

[0072] The ion mobility spectrometer 8 can be, for example, a positive and negative dual-mode ion mobility tube, and an integrated ceramic dual-mode mobility tube can be used, for example. The ion mobility spectrometer 8 can also be a positive or negative single-mode ion mobility tube. The ion mobility spectrometer has the advantages of being portable, fast, sensitive and industrializable, and is widely used in measuring the presence and dose of toxic and harmful gases and / or hazardous chemicals. If the composition of the sample gas to be detected is complex, a chromatographic separation device can be pre-set to achieve triple separation detection. Heating devices may be provided in the areas other than the mass spectrometer and the exhaust gas according to the detection needs to prevent sample residues from occurring. According to actual needs, a dual mobility tube or a dual mobility tube dual mass analyzer scheme may be used to achieve simultaneous positive and negative mode detection.

[0073] According to an exemplary embodiment of another aspect of the present invention, refer to Figure 1 , a method for detecting a sample gas by using the above automatic sampling device 100 is provided, including the following steps: inputting the sample gas into the ion mobility spectrometer 1; controlling the opening or closing of the gate valve 3 by the controller 4 to allow the sample ions discharged from the suppression grid 14 of the ion mobility spectrometer 1 to flow into the mass spectrometer 2 through the through hole 151 of the Faraday disk 15 when the gate valve 3 is opened.

[0074] Specifically, the sample gas is transported to the charge exchange region 181 through the sample input port 17, while the ion source 16 generates charged ions. The sample gas input from the sample input port 17 undergoes charge exchange with the charged ions generated by the ion source 16 in the charge exchange region 181, causing the sample gas to be ionized, thereby generating sample ions. An electric field is formed between the isolation grid 18 and the ion gate 12, and the gaseous sample ions can freely diffuse from the charge exchange region 181 to the ion enrichment cavity 182, and the sample ions are enriched or temporarily stored in the ion enrichment cavity 182. A plurality of electrodes 13 and the suppression grid 14 form an electric field gradient in the migration tube 11, so that the charged sample ions move from the ion enrichment cavity 182 to the migration tube, move in the migration chamber 111 of the migration tube 11, and move to the Faraday disk 15. By changing the potential difference between the electrodes 13 and the suppression grid 14, the migration speed of the sample ions in the migration tube 11 can be changed.

[0075] In one exemplary embodiment, the controller 4 controls the voltages applied to the ion gate 12, the electrodes 13, and the suppression grid 14 of the ion mobility spectrometer 1 to control the operating mode of the ion mobility spectrometer.

[0076] In one exemplary embodiment, referring to Figure 1 and 5 , the steps for the controller 4 to control the voltages applied to the ion gate 12, the electrodes 13, and the suppression grid 14 of the ion mobility spectrometer 1 include: controlling the ion gate 12 to open or close alternately; controlling the voltages applied to the electrodes 13 and the suppression grid 14 such that the sample ions move from the ion gate 12 through the suppression grid 14 and migrate to the Faraday disk 15; and controlling the gate valve 3 to close, so that the gas analysis device operates in the ion mobility spectrometry detection mode.

[0077] In one exemplary embodiment, referring to Figure 1 and 6 , the steps for the controller 4 to control the voltages applied to the ion gate 12, the electrodes 13, and the suppression grid 14 of the ion mobility spectrometer 1 include: controlling the ion gate 12 and the suppression grid 14 to be in a continuously open state; controlling the gate valve 3 to open, such that the sample ions move from the ion gate 12 through the through hole 151 of the Faraday disk 15 and enter the mass spectrometer 2, so that the gas analysis device operates in the mass spectrometry detection mode.

[0078] In one exemplary embodiment, referring to Figure 1 and 7, the steps for the controller 4 to control the voltages applied to the ion gate 12, the electrode 13, and the suppression grid 14 of the ion mobility spectrometer 1 include: controlling the ion gate 12 to open or close alternately; controlling the voltages applied to the electrode 13 and the suppression grid 14 so that sample ions move from the ion gate 12 through the suppression grid 14 and migrate to the Faraday disk 15; and controlling the gate valve 3 to open or close alternately to allow the sample ions to enter the mass spectrometer through the through-hole of the Faraday disk after collecting signals from the Faraday disk, so that the gas analysis device operates in a first hybrid detection mode including an ion mobility spectrometry detection mode and a mass spectrometry detection mode.

[0079] In an exemplary embodiment, refer to Figure 1 and 9 , the steps for the controller 4 to control the voltages applied to the ion gate 12, the electrode 13, and the suppression grid 14 of the ion mobility spectrometer 1 include: controlling the ion gate 12 to open or close alternately; controlling the voltages applied to the electrode 13 and the suppression grid 14 so that sample ions move from the ion gate 12 through the suppression grid 14 and migrate to the Faraday disk 15; and controlling the gate valve 3 to open and controlling the suppression grid to open or close alternately, so that the suppression grid selectively releases part of the sample ions from the ion gate, and the sample ions that have passed through the suppression grid enter the mass spectrometer 2 through the through-hole 151 of the Faraday disk 15, thereby enabling the gas analysis device to operate in a second hybrid detection mode including an ion mobility spectrometry detection mode and a mass spectrometry detection mode.

[0080] In an exemplary embodiment, refer to Figure 1 and 11 , the controller 4 controls the ion gate 12 to open or close alternately; controls the voltages applied to the electrode 13 and the suppression grid 14 so that sample ions move from the ion gate 12 through the suppression grid 14 and migrate to the Faraday disk 15; and controls the gate valve 3 to open so that the sample ions enter the mass spectrometer through the through-hole of the Faraday disk 15 at multiple ion selection time sequences. In this way, the gas analysis device operates in a mass spectrometer enrichment detection mode for detecting multiple ions of a single accumulated sample. Since the sample ion injection time of a single ion trap of the mass spectrometer allows for a time greater than the single scan time of the ion mobility spectrometer, it means that multiple (for example, 6 or 7 times) screenings of sample ions can be performed, and the screened sample ions can be injected into the ion trap in a multiple accumulation manner. As the amount of ions increases, the mass spectrometry signal is enhanced. Figure 11 An example of 7 cumulative injections and one mass spectrometry detection is shown in

[0081] The gas analysis device and the method for detecting a sample gas provided according to the above embodiments of the present disclosure can achieve the combination of a portable ion mobility shift-ion trap mass spectrometer, and select a single detection mode or a plurality of mixed detection modes according to the actual situation.

[0082] Those skilled in the art can understand that the above-described embodiments are all exemplary, and those skilled in the art can make improvements thereto. The structures described in various embodiments can be freely combined without conflict in terms of structure or principle.

[0083] Although the present disclosure has been described in conjunction with the accompanying drawings, the embodiments disclosed in the drawings are intended to exemplarily illustrate the preferred embodiments of the present disclosure and should not be construed as a limitation to the present disclosure. Although some embodiments of the inventive concept of the present disclosure have been shown and described, those of ordinary skill in the art will understand that changes can be made to these embodiments without departing from the principles and spirit of the general inventive concept. The scope of the present disclosure is defined by the claims and their equivalents.

Claims

1. A gas analysis device (100), comprising: Ion mobility spectrometer (1), comprising an ion mobility tube (11), an ion source, an ion gate (12), an isolation grid, a plurality of electrodes (13), a suppression grid (14), and a Faraday disk (15) which are sequentially arranged in the ion mobility tube. A through hole (151) is provided on the Faraday disk. The isolation grid is arranged between the ion source and the ion gate to form a charge exchange region (181) between the ion source and the isolation grid and an ion enrichment cavity (182) between the isolation grid and the ion gate. Mass spectrometer (2); Gate valve (3), arranged between the Faraday disk and the ion inlet of the mass spectrometer; And Controller (4), adapted to control the opening or closing of the gate valve to allow the sample ions discharged from the suppression grid to flow through the through hole of the Faraday disk into the mass spectrometer when the gate valve is opened. Wherein, each of the ion gate (12) and the suppression grid (14) comprises a frame (121) and a metal mesh (122) connected to the frame. By changing the potential difference between the electrode and the suppression grid, the migration speed of the sample ions in the migration tube (11) is changed.

2. The gas analysis device according to claim 1, wherein, The controller is further adapted to control the voltages applied to the ion gate, the electrodes and the suppression grid and the startup of the mass spectrometer to control the working mode of the ion mobility spectrometer.

3. The gas analysis device according to claim 2, wherein, The controller is adapted to control the ion gate to open or close alternately, control the voltages applied to the electrodes and the suppression grid so that the sample ions move from the ion gate through the suppression grid to the Faraday disk, and control the gate valve to close, so that the gas analysis device operates in the ion mobility spectrometry detection mode.

4. The gas analysis device according to claim 2, wherein, The controller is adapted to control the ion gate and the suppression grid to be in a continuous open state and control the gate valve to open, so that the sample ions move from the ion gate through the through hole of the Faraday disk into the mass spectrometer, so that the gas analysis device operates in the mass spectrometry detection mode.

5. The gas analysis device according to claim 2, wherein, The controller is adapted to control the ion gate to open or close alternately, control the voltages applied to the electrodes and the suppression grid so that the sample ions move from the ion gate through the suppression grid to the Faraday disk, and control the gate valve to open or close alternately to allow the sample ions to pass through the through hole of the Faraday disk into the mass spectrometer after collecting signals from the Faraday disk, so that the gas analysis device operates in the first hybrid detection mode including the ion mobility spectrometry detection mode and the mass spectrometry detection mode.

6. The gas analysis device according to claim 2, wherein, The controller is adapted to control the ion gate to open or close alternately, control the voltages applied to the electrodes and the suppression grid so that the sample ions move from the ion gate through the suppression grid to the Faraday disk, and control the suppression grid to open or close alternately to selectively release part of the sample ions through the Faraday disk into the mass spectrometer while collecting signals from the Faraday disk, so that the gas analysis device operates in the second hybrid detection mode including the ion mobility spectrometry detection mode and the mass spectrometry detection mode.

7. The gas analysis device according to claim 2, wherein, The controller is adapted to control the ion gate to open or close alternately, and control the voltages applied to the electrodes and the suppression grid so that sample ions move from the ion gate through the suppression grid and migrate to the Faraday disk, and control the gate valve to open so that the sample ions enter the mass spectrometer through the through-hole of the Faraday disk in a plurality of ion selection time sequences, thereby enabling the gas analysis device to operate in a mass spectrometer enrichment detection mode for detecting multiple ions of a single accumulated sample.

8. The gas analysis device according to any one of claims 1-7, further comprising a signal acquisition device, which obtains a migration spectrum and a mass spectrum based on the sample ions received by the Faraday disk and the sample ions entering the mass spectrometer.

9. The gas analysis device according to any one of claims 1-7, wherein, The ion mobility spectrometer (1) further comprises: A sample inlet (17) for delivering sample gas into the ion mobility tube.

10. The gas analysis device according to claim 1, wherein, The ion mobility tube is provided with a migration gas inlet (112) downstream of the suppression grid and a migration gas outlet (113) upstream of the ion gate.

11. The gas analysis device according to any one of claims 1-7, wherein, The mass spectrometer comprises: An ion focusing device (21) adapted to receive sample ions from the Faraday disk; A vacuum chamber (22) provided with an ion trap adapted to receive sample ions from the ion focusing device and an ion detector for generating a mass spectrum based on the ions collected in the ion trap; and A vacuum device (23) adapted to evacuate the vacuum chamber to a vacuum so that the sample ions move to the ion trap.

12. The gas analysis device according to claim 11, wherein, The mass spectrometer further comprises: A pre-vacuum chamber (24) provided between the ion focusing device and the vacuum chamber; A transfer device (25) provided in the pre-vacuum chamber to transfer the sample ions of the ion focusing device to the ion trap; and A pre-vacuum device (26) adapted to evacuate the pre-vacuum chamber to a vacuum so that the sample ions move from the ion focusing device to the transfer device.

13. The gas analysis device according to claim 12, wherein, The mass spectrometer further comprises a vacuum exhaust port (27) adapted to adjust the air pressures in the pre-vacuum chamber and the vacuum chamber.

14. A method for detecting a sample gas using the gas analysis device according to any one of claims 1-13, comprising the following steps: Input the sample gas into the ion mobility spectrometer; Control the opening or closing of the gate valve to allow the sample ions discharged from the suppression grid of the ion mobility spectrometer to flow into the mass spectrometer through the through-hole of the Faraday disk when the gate valve is open.

15. The method according to claim 14, wherein, Control the voltages applied to the ion gate, electrodes and suppression grid of the ion mobility spectrometer to control the working mode of the ion mobility spectrometer.

16. The method according to claim 15, wherein, The steps of controlling the voltages applied to the ion gate, electrodes and suppression grid of the ion mobility spectrometer include: Control the ion gate to open or close alternately; Control the voltages applied to the electrodes and the suppression grid so that sample ions move from the ion gate through the suppression grid and migrate to the Faraday disk; and Control the gate valve to close, thereby enabling the gas analysis device to operate in an ion mobility spectrometry detection mode.

17. The method according to claim 15, wherein, The steps of controlling the voltages applied to the ion gate, electrodes and suppression grid of the ion mobility spectrometer include: Control the ion gate and the suppression grid to be in a continuously open state; Control the gate valve to open so that sample ions move from the ion gate through the through-hole of the Faraday disk and enter the mass spectrometer, thereby enabling the gas analysis device to operate in a mass spectrometry detection mode.

18. The method according to claim 15, wherein, The steps of controlling the voltages applied to the ion gate, electrodes and suppression grid of the ion mobility spectrometer include: Control the ion gate to open or close alternately; Control the voltages applied to the electrodes and the suppression grid so that sample ions move from the ion gate through the suppression grid and migrate to the Faraday disk; and Control the gate valve to open or close alternately, allowing the sample ions to pass through the through-hole of the Faraday disk and enter the mass spectrometer after collecting signals from the Faraday disk, so that the gas analysis device operates in a first hybrid detection mode including an ion mobility spectrometry detection mode and a mass spectrometry detection mode.

19. The method according to claim 15, wherein, The steps of controlling the voltages applied to the ion gate, electrodes, and suppression grid of the ion mobility spectrometer include: Control the ion gate to open or close alternately; Control the voltages applied to the electrodes and suppression grid so that the sample ions move from the ion gate through the suppression grid and migrate to the Faraday disk; and Control the suppression grid to open or close alternately to selectively release some of the sample ions through the Faraday disk and into the mass spectrometer while collecting signals from the Faraday disk, so that the gas analysis device operates in a second hybrid detection mode including an ion mobility spectrometry detection mode and a mass spectrometry detection mode.

20. The method according to claim 15, wherein, The steps of controlling the voltages applied to the ion gate, electrodes, and suppression grid of the ion mobility spectrometer include: Control the ion gate to open or close alternately; Control the voltages applied to the electrodes and suppression grid so that the sample ions move from the ion gate through the suppression grid and migrate to the Faraday disk; and Control the gate valve to open, allowing the sample ions to enter the mass spectrometer through the Faraday disk at multiple ion selection time sequences, and the gas analysis device operates in a mass spectrometer enrichment detection mode for detecting multiple ions of a single accumulated sample.

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