CN114944322A - Ion lens device and mass spectrometer - Google Patents

Ion lens device and mass spectrometer Download PDF

Info

Publication number
CN114944322A
CN114944322A CN202210707121.4A CN202210707121A CN114944322A CN 114944322 A CN114944322 A CN 114944322A CN 202210707121 A CN202210707121 A CN 202210707121A CN 114944322 A CN114944322 A CN 114944322A
Authority
CN
China
Prior art keywords
ion
electrodes
extraction
deflection
electrode
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN202210707121.4A
Other languages
Chinese (zh)
Inventor
魏君
许春华
莫婷
杨俊林
张宏君
谭国斌
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Guangzhou Hexin Instrument Co Ltd
Original Assignee
Guangzhou Hexin Instrument Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Guangzhou Hexin Instrument Co Ltd filed Critical Guangzhou Hexin Instrument Co Ltd
Priority to CN202210707121.4A priority Critical patent/CN114944322A/en
Publication of CN114944322A publication Critical patent/CN114944322A/en
Pending legal-status Critical Current

Links

Images

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J49/00—Particle spectrometers or separator tubes
    • H01J49/02—Details
    • H01J49/06—Electron- or ion-optical arrangements
    • H01J49/067—Ion lenses, apertures, skimmers
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J49/00—Particle spectrometers or separator tubes
    • H01J49/02—Details
    • H01J49/06—Electron- or ion-optical arrangements
    • H01J49/062—Ion guides
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J49/00—Particle spectrometers or separator tubes
    • H01J49/26—Mass spectrometers or separator tubes

Landscapes

  • Chemical & Material Sciences (AREA)
  • Analytical Chemistry (AREA)
  • Other Investigation Or Analysis Of Materials By Electrical Means (AREA)
  • Electron Tubes For Measurement (AREA)

Abstract

The application relates to an ion lens device and a mass spectrometer, which comprise ion extraction electrodes and an even number of ion transmission electrodes, wherein the ion transmission electrodes are arranged on the ion extraction electrodes at equal intervals and surround an open cylindrical ion transmission channel, and ion extraction holes are arranged on the ion extraction electrodes; the ion extraction electrode and each ion transmission electrode are applied with voltage, an accelerating deflection electric field is formed in the cylindrical ion transmission channel, the ion beam to be detected is introduced into the cylindrical ion transmission channel from the previous stage environment and deflects the movement direction of the ion beam to be detected, so that the ion beam to be detected is transmitted to the next stage environment from the ion extraction hole, neutral particles and photons which are not subjected to the electric field deflection effect are removed, the structure of the off-axis type ion lens can also have higher ion transmission efficiency, and the instrument sensitivity is higher.

Description

Ion lens device and mass spectrometer
Technical Field
The application relates to the technical field of mass spectrometry instruments, in particular to an ion lens device and a mass spectrometer.
Background
The mass spectrometer is one of the most basic instruments for researching the basic composition, structural characteristics, physical and chemical properties of substances, is a necessary instrument in the fields of life science, material science, food safety, environmental protection and the like, and is the core of a modern analytical instrument. The essence of the mass spectrometer is that the detection of the composition of a compound is realized after moving ions are separated according to the mass-to-charge ratio under a vacuum environment by utilizing an electric field and/or a magnetic field. The ion lens device is a key transmission device in a mass spectrometer, and is required to gather and guide ions to be analyzed to reach a mass spectrometry device from an interface region, and simultaneously, background noises such as neutral particles, photons and the like are prevented from passing through, so that the sensitivity, detection limit and background noise level of the instrument are determined.
Currently, the ion lens devices commonly used in the ion deflection mode may include an optical baffle type, a 90-degree deflection type, and the like. Although the optical baffle can well eliminate the interference between neutral particles and photons, the loss of ions to be measured is serious, and the sensitivity of the instrument is reduced. The 90-degree deflection type cannot particularly stabilize the focusing point for elements with different masses, and even ions in the transmission process may deflect to the outside of the device, which also causes the problem of reduced sensitivity.
Disclosure of Invention
Accordingly, it is desirable to provide an ion lens device and a mass spectrometer, which are directed to the problem of the conventional ion lens device that the sensitivity of ion detection is reduced.
An ion lens device comprises ion extraction electrodes and an even number of ion transmission electrodes, wherein the ion transmission electrodes are arranged on the ion extraction electrodes at equal intervals and surround an open cylindrical ion transmission channel, and ion extraction holes are formed in the ion extraction electrodes;
and voltages are applied to the ion extraction electrodes and the ion transmission electrodes, an accelerating deflection electric field is formed in the cylindrical ion transmission channel, the ion beam to be detected is introduced into the cylindrical ion transmission channel from the previous stage environment, the movement direction of the ion beam to be detected is deflected, and the ion beam to be detected is transmitted to the next stage environment from the ion extraction hole.
In one embodiment, the number of the ion transmission electrodes is at least four, and the ion transmission electrodes include a pair of ion acceleration electrodes disposed opposite to each other and at least a pair of ion deflection electrodes disposed opposite to each other, the distances between each ion acceleration electrode and the ion extraction hole are the same, the voltages applied by each ion acceleration electrode are the same, the distances between two oppositely disposed ion deflection electrodes and the ion extraction hole are different, and the voltage applied by the ion deflection electrode near the ion extraction hole is greater than the voltage applied by the ion deflection electrode far from the ion extraction hole.
In one embodiment, the polarity of the voltage applied by each of the ion accelerating electrodes and each of the ion deflecting electrodes is the same.
In one embodiment, each of the ion accelerating electrodes and each of the ion deflecting electrodes are stainless steel electrodes.
In one embodiment, each of the ion accelerating electrodes and each of the ion deflecting electrodes is a box-shaped electrode having a through hole in the middle.
In one embodiment, each of the ion accelerating electrodes and each of the ion deflecting electrodes are provided with a wire.
In one embodiment, the number of the ion transmission electrodes is two, the two ion transmission electrodes are oppositely arranged to serve as ion deflection electrodes, the distances between the two ion deflection electrodes and the ion extraction hole are different, and the voltage applied to the ion deflection electrode close to the ion extraction hole is larger than the voltage applied to the ion deflection electrode far away from the ion extraction hole.
In one embodiment, the ion lens apparatus further includes a rotating mechanism connected to the ion extraction electrodes, and the rotating mechanism is configured to drive the ion extraction electrodes and the ion transmission electrodes to rotate along a central axis of the cylindrical ion transmission channel, so as to adjust positions of the ion extraction holes on the ion extraction electrodes.
In one embodiment, a mass spectrometer is provided, which includes an ion generating device, an ion interface device, a collision reaction device, a mass analysis device, and the ion lens device, where the ion generating device is configured to generate an ion beam to be detected, and the ion beam to be detected enters the mass analysis device to complete mass analysis after passing through the ion interface device, the ion lens device, and the collision reaction device in sequence.
In one embodiment, the ion lens device is disposed between the ion interface device and the collision reaction device, and between the collision reaction device and the mass analysis device.
According to the ion lens device and the mass spectrometer, the ion extraction electrodes and the even number of ion transmission electrodes are encircled to form the cylindrical ion transmission channel with one open end, the voltage is applied to the ion extraction electrodes and the ion transmission electrodes, the accelerating deflection electric field is formed in the cylindrical ion transmission channel, the ion beam to be detected is introduced into the cylindrical ion transmission channel from the previous stage environment to be deflected and then is transmitted to the next stage environment from the ion extraction hole, neutral particles and photons which are not subjected to the electric field deflection effect can be removed, the structure of the off-axis ion lens can have higher ion transmission efficiency, and the sensitivity of the instrument is higher.
Drawings
FIG. 1 is a schematic rear view of an ion lens apparatus according to an embodiment;
FIG. 2 is a schematic diagram illustrating a side view of an ion lens apparatus according to an embodiment;
FIG. 3 is a schematic front view of an ion lens apparatus according to an embodiment;
FIG. 4 is a schematic diagram of an embodiment in which the ion transport electrode is a square frame electrode;
FIG. 5 is a schematic diagram of an embodiment in which the ion transport electrode is a wire-backed square electrode;
FIG. 6 is a schematic diagram illustrating a movement trajectory of an ion beam to be measured in an ion lens apparatus according to an embodiment;
FIG. 7 is a diagram illustrating deflection trajectories for an embodiment in which ion masses of the ion beam to be measured correspond to 9amu, 115amu, and 209 amu;
FIG. 8 is a block diagram of a mass spectrometer in an embodiment.
Detailed Description
In order to make the objects, technical solutions and advantages of the present application more apparent, the present application is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present application and are not intended to limit the present application.
Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in the description of the present application herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.
It will be understood that, as used herein, the terms "first," "second," and the like may be used herein to describe various elements, but these elements are not limited by these terms. These terms are only used to distinguish one element from another. For example, a first resistance may be referred to as a second resistance, and similarly, a second resistance may be referred to as a first resistance, without departing from the scope of the present application. The first resistance and the second resistance are both resistances, but they are not the same resistance.
It is to be understood that "connection" in the following embodiments is to be understood as "electrical connection", "communication connection", and the like if the connected circuits, modules, units, and the like have communication of electrical signals or data with each other.
As used herein, the singular forms "a", "an" and "the" may include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises/comprising," "includes" or "including," etc., specify the presence of stated features, integers, steps, operations, components, parts, or combinations thereof, but do not preclude the presence or addition of one or more other features, integers, steps, operations, components, parts, or combinations thereof.
As mentioned in the background, mass spectrometers are the heart of modern analytical instruments and are essentially the detection of the composition of compounds by separating the moving ions by mass to charge ratio in a vacuum environment using electric and/or magnetic fields. The ion lens device is a key transmission device in a mass spectrometer, and is required to gather and guide ions to be analyzed to reach a mass spectrometry device from an interface region, and simultaneously, background noises such as neutral particles, photons and the like are prevented from passing through, so that the sensitivity, detection limit and background noise level of the instrument are determined. Currently, the ion lens devices commonly used in the ion deflection mode may include an optical baffle type, a 90-degree deflection type, and the like. Although the optical baffle can well eliminate the interference between neutral particles and photons, the loss of ions to be measured is serious, and the sensitivity of the instrument is reduced. For elements with different masses, the 90-degree deflection type needs frequent voltage adjustment, the ion focusing point cannot be particularly stable, and even some ions in the transmission process may deflect to the outside of the device, which also causes the problem of sensitivity reduction.
Based on this, this application provides an ion lens device is applied to the mass spectrograph, specifically is applied to needs gathering and guide the ion beam that awaits measuring and realizes the direction of motion deflection, gets rid of scenes such as background noise such as neutral particle and photon in the ion beam that awaits measuring simultaneously. For example, the ion beam collision reaction device can be applied between an ion interface device and a collision reaction device to remove neutral molecules and photons in an ion beam to be detected. The ion source can also be applied between a collision reaction device and a mass analysis device to remove neutral molecules generated in the collision reaction device due to ion collision or a reaction process. Specifically, an ion extraction electrode and an even number of ion transmission electrodes are encircled to form a cylindrical ion transmission channel with an opening at one end, a voltage is applied to the ion extraction electrode and each ion transmission electrode to form an accelerating deflection electric field in the cylindrical ion transmission channel, an ion beam to be detected is introduced into the cylindrical ion transmission channel from a previous-stage environment to be deflected and then is transmitted to a next-stage environment from an ion extraction hole, neutral particles and photons which are not subjected to the electric field deflection effect are removed, and the structure of the off-axis ion lens can also have higher ion transmission efficiency, so that the sensitivity of an instrument for detecting the ion beam to be detected is higher.
In one embodiment, as shown in fig. 1 and fig. 2, an ion lens apparatus is provided, which includes an ion extraction electrode 110 and an even number of ion transmission electrodes 120, each ion transmission electrode 120 is disposed at equal intervals on the ion extraction electrode 110, and surrounds an open cylindrical ion transmission channel, and an ion extraction hole 130 is disposed on the ion extraction electrode 110; voltages are applied to the ion extraction electrode 110 and each ion transmission electrode 120, an accelerating deflection electric field is formed in the cylindrical ion transmission channel, the ion beam to be detected is introduced into the cylindrical ion transmission channel from the previous stage environment, and the movement direction of the ion beam to be detected is deflected, so that the ion beam to be detected is transmitted to the next stage environment from the ion extraction hole 130.
Specifically, each ion transmission electrode 120 is disposed perpendicular to the ion extraction electrode 110, and encloses an open cylindrical ion transmission channel with the ion extraction electrode 110. It can be understood that the central axis direction of the cylindrical ion transmission channel is parallel to the movement direction of the ion beam to be detected, so that the ion beam to be detected is injected from the opening, and is injected from the ion extraction hole 130 arranged on the ion extraction electrode 110 to the next stage environment after passing through the cylindrical ion transmission channel, thereby ensuring the transmission efficiency of the ions.
The ion transmission electrodes 120 are arranged in pairs, and are arranged at equal intervals on the ion extraction electrode 110 to form a cylindrical ion transmission channel, and the paired ion transmission electrodes 120 are arranged oppositely, so that when a voltage is applied to form an accelerating deflection electric field, the ion beam to be detected keeps the original shape of the ion beam and is not dispersed, and the ion transmission efficiency is improved. Correspondingly, in order to keep the overall shape of the device consistent, the ion extraction electrode 110 may be a circular electrode having the same diameter as the cross section of the cylindrical ion transmission channel, and the circular electrode is disposed coaxially with the cylindrical ion transmission channel. Further, the number of the ion transmission electrodes 120 is even, and may be two or more pairs of semicircular ion transmission electrodes 120 or two or more pairs of arc-shaped ion transmission electrodes 120. The sizes of the ion extraction electrode 110 and the ion transmission electrode 120 and the size of the formed cylindrical ion transmission channel are not unique, and can be set according to the size of the mass spectrometer. For example, in the present embodiment, the thickness of the ion extraction electrode 110 is 1mm, the thickness of each ion transmission electrode 120 is 4mm, the radius of the enclosed cylindrical ion transmission channel is 18.5mm, and the length is 26 mm.
Further, in order to remove background noise such as neutral particles and photons in the ion beam to be measured, voltages are applied to the ion extraction electrode 110 and each ion transmission electrode 120, and an accelerating deflection electric field is formed in the cylindrical ion transmission channel. Meanwhile, the position of the ion extraction hole 130 on the ion extraction electrode 110 deviates from the beam spot position of the ion beam to be detected on the ion extraction electrode 110, so that the ion beam to be detected realizes the deflection of the movement direction under the action of the deflection electric field and is transmitted to the next stage environment from the ion extraction hole 130. It can be understood that background noise such as neutral particles and photons is not affected by electric field. If the neutral particles and the photons have certain kinetic energies, the beam spot position on the ion extraction electrode 110 along the incident direction of the ion beam to be detected is removed, and if the kinetic energies are smaller, the beam spot position is extracted by the vacuum equipment and removed. It can be understood that the ion extraction electrode 110 and each ion transmission electrode 120 are fixed by an insulating material to ensure that they do not affect each other and maintain the electric field stable.
The distance of the ion extraction hole 130 from the beam spot position of the ion beam to be measured on the ion extraction electrode 110 along the incident direction is not limited, and can be set according to the actual ion mass and the deflection electric field condition. However, it is necessary to ensure that there is no overlapping portion between the ion extraction aperture 130 and the beam spot position of the ion beam to be measured on the ion extraction electrode 110, so as to ensure the effect of removing background noise such as neutral particles and photons. In addition, the size of the ion extraction aperture 130 is not unique and may be set according to the diameter of the ion beam to be measured, for example, in the present embodiment, the radius of the ion extraction aperture 130 may be set to 2mm to 4 mm. In the embodiment of the present application, in order to facilitate the control of the ion beam transmission path, the ion beam to be measured is injected along the central axis of the cylindrical ion transmission channel, and the ion extraction hole 130 is eccentrically disposed on the ion extraction electrode 110. The eccentric distance of the ion extraction hole 130 can be set according to the deflection angle requirement of the ion beam to be measured.
The formation of the accelerating deflection electric field in the cylindrical ion transport channel can be achieved by applying voltages of different polarities or amplitudes to the ion extraction electrode 110 and each ion transport electrode 120. For example, a positive voltage or a negative voltage with the same polarity may be applied to each ion transport electrode 120, and a negative voltage may be applied to the ion extraction electrode 110, so as to form an accelerating electric field with the same direction as the movement direction of the ion beam to be measured, so that the ion beam to be measured is accelerated to fly from the cylindrical ion transport channel into the next environment. Meanwhile, the voltage of the ion transmission electrode 120 close to the ion extraction hole 130 is set to be larger than that of the ion transmission electrode 120 far from the ion extraction hole 130, so that a deflection electric field deflecting towards the ion extraction hole 130 is formed, the deflection of the movement direction of the ion beam to be measured is realized, and the ion beam flies out from the ion extraction hole 130.
Further, the ion lens apparatus includes a power supply unit for applying a voltage to the ion extraction electrode 110 and each ion transmission electrode 120. The power supply unit is connected with an external power supply, and the power supply voltage of the power supply is subjected to voltage boosting and reducing treatment to obtain direct current voltage according with the polarities and the magnitudes of the ion extraction electrode 110 and each ion transmission electrode 120, and the direct current voltage is correspondingly output to the ion extraction electrode 110 and each ion transmission electrode 120. In addition, the ion lens apparatus further includes a controller, and the controller is configured to control the polarity and magnitude of the voltage applied to the ion extraction electrode 110 and each ion transmission electrode 120 by the power supply unit, so as to adjust the deflection angle of the ion beam to be measured, and obtain the optimal ion transmission efficiency. It can be understood that the controller and the power supply unit can be implemented by sharing existing devices in the mass spectrometer, or can be separately added to the ion lens device of the stage.
According to the ion lens device, the ion extraction electrodes and the even number of ion transmission electrodes are encircled to form the cylindrical ion transmission channel with one open end, the voltage is applied to the ion extraction electrodes and the ion transmission electrodes to form the accelerated deflection electric field in the cylindrical ion transmission channel, the ion beam to be detected is introduced into the cylindrical ion transmission channel from the previous stage environment to be deflected and then is transmitted to the next stage environment from the ion extraction hole, neutral particles and photons which are not subjected to the electric field deflection action are removed, the structure of the off-axis ion lens can have higher ion transmission efficiency, and the sensitivity of an instrument is higher.
In one embodiment, as shown in fig. 2 and 3, the number of the ion transmission electrodes 120 is at least four, and the ion transmission electrodes include a pair of oppositely disposed ion acceleration electrodes 122 and at least a pair of oppositely disposed ion deflection electrodes 121, each of the ion acceleration electrodes 122 has the same distance to the ion extraction aperture 130, and the voltages applied to the ion acceleration electrodes 122 are equal, the distances between the two oppositely disposed ion deflection electrodes 121 and the ion extraction aperture 130 are different, and the voltage applied to the ion deflection electrode 121 near the ion extraction aperture 130 is greater than the voltage applied to the ion deflection electrode 121 far from the ion extraction aperture 130.
Specifically, the distances from the oppositely disposed ion accelerating electrodes 122 to the ion extraction hole 130 are the same, and are used for controlling the kinetic energy of the ion beam to be detected along the central axis direction of the cylindrical ion transmission channel, and drawing the ion beam to be detected to move. And the voltages applied by the ion accelerating electrodes 122 are equal in magnitude, and have no deflection effect on the ion beam to be measured. Therefore, in other embodiments, the controller may adjust the voltage applied to the ion accelerating electrode 122 by the power supply unit according to the incident kinetic energy of the ion beam to be measured, so as to adjust the movement speed of the ion beam to be measured as required. In addition, the incident kinetic energy of the ion beam to be measured from the previous level environment can be reduced, so that more neutral particles and photons are pumped out in the ion lens device of the current level in a vacuum manner, the pollution to the pole piece in the ion lens device of the current level is reduced, and the kinetic energy of the ion beam to be measured is improved by increasing the voltage applied by each ion acceleration electrode 122.
Further, the number of the ion deflection electrodes 121 may be only one pair, as shown in fig. 2 and 3, or may be two or more pairs, without limitation. The distances between the two oppositely arranged ion deflection electrodes 121 and the ion extraction hole 130 are different, and the voltage applied by the ion deflection electrode 121 close to the ion extraction hole 130 is greater than the voltage applied by the ion deflection electrode 121 far from the ion extraction hole 130, so that the ion beam to be detected can be deflected towards the ion deflection electrode 121 close to the ion extraction hole 130. The controller adjusts the voltage applied to the two-sided ion deflection electrodes 121 by the power supply unit, so that the ion beam to be measured can accurately fly out of the ion extraction hole 130, and background noise such as neutral particles, photons and the like can be removed without the action of an electric field.
The voltages applied by the ion deflection electrodes 121 and the ion acceleration electrodes 122 are determined according to the mass, the quantity and the incident kinetic energy of the detected ion beam. In the present embodiment, the voltage applied to each ion deflection electrode 121 and each ion acceleration electrode 122 can be set between-200V and 200V. The voltages of the two ion accelerating electrodes 122 may be selected first, and then the voltage of each ion deflecting electrode 121 is obtained by increasing or decreasing the preset voltage difference according to the voltage of the ion accelerating electrode 122. The voltage applied to the ion deflection electrode 121 near the ion extraction aperture 130 is a voltage increase of the ion acceleration electrode 122 by a predetermined voltage difference, and the voltage applied to the ion deflection electrode 121 far from the ion extraction aperture 130 is a voltage decrease of the ion acceleration electrode 122 by a predetermined voltage difference. The preset voltage difference can also be selected according to actual needs, for example, 15V in this embodiment.
In one embodiment, each ion accelerating electrode 122 is in accordance with the polarity of the voltage applied by each ion deflecting electrode 121. The polarities of the voltages applied to the ion accelerating electrodes 122 and the ion deflecting electrodes 121 may be both positive and negative. The voltage applied by the ion extraction electrode 130 may be a positive polarity voltage or a negative polarity voltage.
In another embodiment, the number of the ion transmission electrodes 120 may be two, two ion transmission electrodes are oppositely disposed as the ion deflection electrodes 121, the distances between the two ion deflection electrodes 121 and the ion extraction aperture 130 are different, and the voltage applied to the ion deflection electrode 121 close to the ion extraction aperture 130 is greater than the voltage applied to the ion deflection electrode 121 far from the ion extraction aperture 130. Similarly, the ion beam to be detected can be deflected towards the ion deflection electrode 121 close to the ion extraction hole 130, and then the controller adjusts the voltage applied to the two ion deflection electrodes 121 by the power supply unit, so that the ion beam to be detected can accurately fly out of the ion extraction hole 130. Further, the purpose of accelerating the ion beam to be measured can also be achieved by setting the voltage of the two ion deflection electrodes 121 to be smaller than the voltage applied by the ion extraction electrode 130.
In one embodiment, each ion accelerating electrode and each ion deflecting electrode is a stainless steel electrode. The ion accelerating electrodes and the ion deflecting electrodes are made of stainless steel materials, so that the electrodes are not easy to rust, deform and oxidize, and the service life is longer. In addition, the stainless steel electrode has good conductivity, does not influence the electric field distribution of the electrode, and can well realize the acceleration and deflection of the ion beam to be measured.
In one embodiment, as shown in fig. 4, each of the ion accelerating electrodes and each of the ion deflecting electrodes are each a rectangular frame-shaped electrode having a through hole in the middle. In the present embodiment, the through holes are formed between the ion accelerating electrodes and the ion deflecting electrodes to form the square frame-shaped electrodes, so that neutral particles and photons are not attached to the ion accelerating electrodes and the ion deflecting electrodes when the ion lens device is vacuumized, thereby reducing the contamination of the electrode plates in the ion lens device.
Further, when the front stage of the present stage ion lens device is provided with the pole piece, in order to maintain the vacuum degree of the opened cylindrical ion transport channel, in one embodiment, as shown in fig. 5, each of the ion accelerating electrodes and each of the ion deflecting electrodes are provided with a metal wire. The metal wire can be arranged on the square electrode in a winding or fixing mode, and the through hole in the middle of the metal wire is in a net shape. When a voltage is applied to each of the ion accelerating electrodes and each of the ion deflecting electrodes, the wires are also electrified in synchronization to maintain the degree of vacuum of the open cylindrical ion transport channel. Meanwhile, the reticular metal wire structure can also reduce the attachment of neutral particles and photons, thereby achieving the purpose of reducing the pollution to the pole piece in the ion lens device of the current level.
In one embodiment, the ion lens apparatus further includes a rotation mechanism connected to the ion extraction electrode, and the rotation mechanism is configured to drive the ion extraction electrode and each ion transmission electrode to rotate along a central axis of the cylindrical ion transmission channel, so as to adjust a position of the ion extraction hole on the ion extraction electrode. It can be understood that, because the ion lens device of the present application has a cylindrical structure, the position of the ion extraction hole on the ion extraction electrode can be arbitrarily adjusted within a range of 360 degrees around the central axis of the ion transmission channel. Under the control of the same group of voltages of the ion extraction electrode and each ion transmission electrode, the ion beam to be detected can deflect and fly out at multiple angles, and the ion beam can be conveniently adapted to the position of the next device.
Fig. 6 is a diagram illustrating a motion trajectory of an ion beam 10 to be measured, which has an ion mass of 115amu and an ion number of 100, through the ion lens apparatus of the present application in one embodiment. Specifically, after ions in the ion beam 10 to be measured enter the ion lens device, the controller controls the power supply unit to adjust the voltage of the ion acceleration electrode 122 to 100V according to the incident kinetic energy of the ions, so that the ion acceleration electrode 122 controls the transverse kinetic energy of the ions, and the ion beam 10 to be measured is pulled to move axially in the cylindrical ion channel. And then the controller controls the power supply unit to control the voltage of the ion deflection electrode 121 which is oppositely arranged to be 110V and 95V, so that the track deflection of the ion beam 10 to be detected is realized, the ion beam smoothly flies out of the ion lens device under the traction action of the ion extraction electrode 130 and enters the next stage of transmission, and at the moment, the deflection angle of the ion beam 10 to be detected is about 14 degrees, and the transmission efficiency is highest.
As shown in (a), (b) and (c) of fig. 7, the deflection trajectory diagrams are obtained when the ion mass of the ion beam to be measured is 9amu, 115amu and 209amu when the voltage of the two selected ion accelerating electrodes 122 is 100V, the voltage of the oppositely disposed ion deflecting electrode 121 is 110V and 95V, and the voltage of the ion extracting electrode 130 is-10V. It can be known through contrastive analysis that the ion lens device of this application all has better transmission efficiency to the ion of different mass numbers, gets into next grade transmission to the ion homoenergetic of full mass range smoothly through lens after selecting a set of suitable voltage, need not frequently adjust pole piece voltage.
In one embodiment, as shown in fig. 8, a mass spectrometer is provided, which includes an ion generating device 21, an ion interface device 22, a collision reaction device 24, a mass analysis device 25, and the above ion lens device 23, wherein the ion generating device 21 is configured to generate an ion beam to be measured, and the ion beam to be measured enters the mass analysis device 25 to complete mass analysis after passing through the ion interface device 22, the ion lens device 23, and the collision reaction device 24 in sequence.
Specifically, the sample is ionized by the ion generating device 21 to obtain an ion beam to be detected, the ion beam to be detected enters the mass spectrum cavity 26 through the ion interface device 22, and neutral particles and photons enter the mass spectrum cavity 26 and are removed through the ion lens device 23. The ion extraction electrode of the ion lens device 23 can be used as an entrance pole piece of the collision reaction device 24, the ion beam to be detected is collided or reacted by the collision reaction device 24 to further remove the polyatomic interference and mass spectrum interference, and then enters the mass analysis device 25 to complete the quantitative or qualitative analysis of the sample.
The ion interface device 22 includes a sampling cone 32, a capturing cone 33 and an extraction lens 34, belongs to an interface part of a mass spectrometer, and realizes transition of a vacuum environment and extraction of an ion beam to be detected. The vacuum environment of the interface part is obtained by pumping through a pumping port 35 by a mechanical pump 31, and the vacuum degree is required to be less than 200 Pa. The ion lens device 23 and the collision reaction device 24 belong to an ion transmission part of a mass spectrometer, the vacuum environment of the ion transmission part is connected with a pumping port 27 through a molecular pump 29 to pump vacuum, and the vacuum degree is controlled at 10 -2 -10 -3 Pa. The mass analyzer 25 is connected with a pumping port 28 through a molecular pump 30 to pump vacuum, and the vacuum degree is controlled at 10 -5 -10 -6 Pa。
In addition, the Mass spectrometer mentioned in the examples of the present application is an Inductively Coupled Plasma Mass spectrometer (ICP-MS). The ion generating device 21 is a device for applying high frequency power to plasma formed on a coil coupled to a torch. The mass analysis device 25 may be implemented by a quadrupole mass spectrometer, a magnetic field mass spectrometer, a time-of-flight mass spectrometer, or the like.
In one embodiment, ion lens devices are disposed between the ion interface device and the collision reaction device, and between the collision reaction device and the mass analysis device.
Specifically, the ion lens device can be applied between an ion interface device and a collision reaction device to remove neutral molecules and photons in an ion beam to be detected. The ion source can also be applied between a collision reaction device and a mass analysis device to remove neutral molecules generated in the collision reaction device due to ion collision or a reaction process.
When the ion accelerating electrode is applied between an ion interface device and a collision reaction device, the ion accelerating electrode and the ion deflecting electrode can adopt a square-frame-shaped electrode with a through hole in the middle, wherein the transmission hole is smaller after the ion extracting lens 34 is installed, and the vacuum degree in the ion lens device can be better ensured. When the ion beam is applied between the collision reaction device and the mass analysis device, the preceding stage collision reaction device is an output pole piece, so that the vacuum degree in the ion lens device cannot be better ensured, and metal wires are required to be arranged in the through holes of the ion acceleration electrodes and the ion deflection electrodes.
The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.
The above-mentioned embodiments only express several embodiments of the present application, and the description thereof is specific and detailed, but not to be understood as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the concept of the present application, which falls within the scope of protection of the present application. Therefore, the protection scope of the present patent shall be subject to the appended claims.

Claims (10)

1. An ion lens device is characterized by comprising ion extraction electrodes and an even number of ion transmission electrodes, wherein the ion transmission electrodes are arranged on the ion extraction electrodes at equal intervals and surround an open cylindrical ion transmission channel, and ion extraction holes are formed in the ion extraction electrodes;
and voltages are applied to the ion extraction electrodes and the ion transmission electrodes, an accelerating deflection electric field is formed in the cylindrical ion transmission channel, the ion beam to be detected is introduced into the cylindrical ion transmission channel from the previous stage environment, the movement direction of the ion beam to be detected is deflected, and the ion beam to be detected is transmitted to the next stage environment from the ion extraction hole.
2. The ion lens apparatus of claim 1, wherein the number of the ion transmission electrodes is at least four, and the ion transmission electrodes comprise a pair of oppositely disposed ion acceleration electrodes and at least a pair of oppositely disposed ion deflection electrodes, each of the ion acceleration electrodes has the same distance to the ion extraction aperture, and the voltages applied to the ion acceleration electrodes are equal, the distances between the two oppositely disposed ion deflection electrodes and the ion extraction aperture are different, and the voltage applied to the ion deflection electrode near the ion extraction aperture is greater than the voltage applied to the ion deflection electrode far from the ion extraction aperture.
3. The ion lens arrangement of claim 2, wherein each of said ion accelerating electrodes is of the same polarity as the voltage applied by each of said ion deflecting electrodes.
4. The ion lens arrangement of claim 2, wherein each of the ion accelerating electrodes and each of the ion deflecting electrodes are stainless steel electrodes.
5. The ion lens arrangement of claim 2, wherein each of the ion accelerating electrodes and each of the ion deflecting electrodes is a box-shaped electrode having a through hole in the middle.
6. The ion lens arrangement according to claim 5, wherein each of the ion accelerating electrodes and each of the ion deflecting electrodes are provided with a wire.
7. The ion lens apparatus of claim 1, wherein the number of the ion transmission electrodes is two, the two ion transmission electrodes are oppositely disposed to serve as ion deflection electrodes, the distances between the two ion deflection electrodes and the ion extraction aperture are different, and the voltage applied to the ion deflection electrode near the ion extraction aperture is greater than the voltage applied to the ion deflection electrode far from the ion extraction aperture.
8. The ion lens apparatus according to any of claims 1 to 7, further comprising a rotation mechanism connected to the ion extraction electrodes, wherein the rotation mechanism is configured to drive the ion extraction electrodes and the ion transmission electrodes to rotate along a central axis of the cylindrical ion transmission channel, so as to adjust positions of the ion extraction holes on the ion extraction electrodes.
9. A mass spectrometer comprising an ion generating device, an ion interface device, a collision reaction device, a mass analysis device and the ion lens device of any one of claims 1 to 8, wherein the ion generating device is configured to generate an ion beam to be detected, and the ion beam to be detected enters the mass analysis device to complete mass analysis after passing through the ion interface device, the ion lens device and the collision reaction device in sequence.
10. The mass spectrometer of claim 9, wherein the ion lens arrangement is disposed between the ion interface arrangement and the collision reaction arrangement, and between the collision reaction arrangement and the mass analysis arrangement.
CN202210707121.4A 2022-06-21 2022-06-21 Ion lens device and mass spectrometer Pending CN114944322A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202210707121.4A CN114944322A (en) 2022-06-21 2022-06-21 Ion lens device and mass spectrometer

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202210707121.4A CN114944322A (en) 2022-06-21 2022-06-21 Ion lens device and mass spectrometer

Publications (1)

Publication Number Publication Date
CN114944322A true CN114944322A (en) 2022-08-26

Family

ID=82910615

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202210707121.4A Pending CN114944322A (en) 2022-06-21 2022-06-21 Ion lens device and mass spectrometer

Country Status (1)

Country Link
CN (1) CN114944322A (en)

Similar Documents

Publication Publication Date Title
US9679755B2 (en) Ionization apparatus
JP4384542B2 (en) Mass spectrometer
US8324565B2 (en) Ion funnel for mass spectrometry
US8525106B2 (en) Method and apparatus for transmitting ions in a mass spectrometer maintained in a sub-atmospheric pressure regime
JP6666919B2 (en) Electron-induced dissociation device and method
EP3607576B1 (en) Ion transfer from electron ionization sources
US9287103B2 (en) Ion guide for mass spectrometry
EP0210182B1 (en) Secondary ion collection and transport system for ion microprobe
US4814613A (en) Collision cell for triple quadrupole tandem mass spectrometry
US7629575B2 (en) Charge control for ionic charge accumulation devices
CN1816383A (en) Mass spectrometer and related ionizer and methods
JP2004071470A (en) Atmospheric pressure plasma ionizing source mass spectrometer
CN103531432B (en) A kind of method of pulsed ion source, mass spectrometer and generation ion
CN114944322A (en) Ion lens device and mass spectrometer
JPH09306418A (en) Plasma ion source mass analyzer
US10658167B2 (en) Off-axis ionization devices and systems using them
US9431228B2 (en) Ion lens for reducing contaminant effects in an ion guide of a mass spectrometer
CN114944323A (en) Ion deflection device and mass spectrometer
US20220336199A1 (en) Axially progressive lens for transporting charged particles
WO2023028696A1 (en) Method and apparatus to increase sensitivity of inductively coupled plasma mass spectrometry
CN113614877A (en) Interference suppression in mass spectrometers
CN117690777A (en) Multi-deflection branch ion guiding device and method based on electrostatic field and mass spectrometer
CN113871286A (en) Ion guide with different multipoles

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination