CN112599403A - Ion funnel device for mass spectrum ionization source - Google Patents

Ion funnel device for mass spectrum ionization source Download PDF

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Publication number
CN112599403A
CN112599403A CN202011481404.9A CN202011481404A CN112599403A CN 112599403 A CN112599403 A CN 112599403A CN 202011481404 A CN202011481404 A CN 202011481404A CN 112599403 A CN112599403 A CN 112599403A
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ion funnel
pole piece
ionization source
ion
mass spectrometry
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李海洋
李函蔚
花磊
蒋吉春
吴称心
徐楚婷
厉梅
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Dalian Institute of Chemical Physics of CAS
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Dalian Institute of Chemical Physics of CAS
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    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01JELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J49/00Particle spectrometers or separator tubes
    • H01J49/02Details
    • H01J49/06Electron- or ion-optical arrangements
    • H01J49/062Ion guides
    • H01J49/065Ion guides having stacked electrodes, e.g. ring stack, plate stack
    • H01J49/066Ion funnels

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

Abstract

本发明公开了一种用于质谱电离源中的离子漏斗装置,涉及质谱分析仪器。具体结构包括绕中心轴线360°一周带有六根支撑杆的离子漏斗支撑台、离子漏斗极片、绝缘PEEK垫和紧固螺母。离子沿着离子漏斗中心轴线方向由中间口径大的离子漏斗极片入射,并从中间口径小的离子漏斗极片出射,所有离子漏斗极片均中间圆孔的平板结构,并且平行、同轴、绝缘放置。本离子漏斗装置以最小的尺寸设计,目的在于使质谱电离源的结构空间尽量小巧,在保证离子漏斗作用的同时缩减了常规离子漏斗的绝对尺寸。该新型的离子漏斗装置技术大大缩减空间尺寸,并且使用效果与常规离子漏斗装置功能相同,在质谱分析仪器简便化、小巧化结构设计中具有广阔的应用前景。

Figure 202011481404

The invention discloses an ion funnel device used in a mass spectrometry ionization source, and relates to a mass spectrometry instrument. The specific structure includes an ion funnel support table with six support rods around the central axis 360°, an ion funnel pole piece, an insulating PEEK pad and a fastening nut. The ions are incident along the central axis of the ion funnel from the ion funnel pole piece with a large middle diameter, and exit from the ion funnel pole piece with a small middle diameter. Insulated placement. The ion funnel device is designed with the smallest size, aiming at making the structure space of the mass spectrometer ionization source as small as possible, and reducing the absolute size of the conventional ion funnel while ensuring the function of the ion funnel. The new ion funnel device technology greatly reduces the space size, and the use effect is the same as that of the conventional ion funnel device, and has broad application prospects in the simple and compact structure design of mass spectrometry instruments.

Figure 202011481404

Description

Ion funnel device for mass spectrum ionization source
Technical Field
The invention belongs to the field of analytical chemical instruments, particularly relates to a mass spectrometry instrument, and particularly relates to an ion funnel device used in a mass spectrometry ionization source.
Background
The mass spectrometer is a chemical analyzer with very high precision, but in order to improve the sensitivity and resolution, the components of the mass spectrometer need to be continuously improved to meet higher requirements. The mass spectrometer mainly ionizes a sample, and the sample can be better analyzed only by a better ionization source, so that the research on the performance of the ionization source of the mass spectrometer is particularly important, and the ion funnel device not only can perform focusing transmission on the sample, but also plays a particularly important role in dissociation analysis of the sample.
The patent No. ZL201711204824.0 discloses a photoionization and chemical ionization combined ion source (patent No. ZL201711204824.0) which comprises a closed chamber, wherein a grid electrode is arranged in the middle of the closed chamber, and the closed chamber is divided into a left independent chamber and a right independent chamber by the grid electrode, namely a photoionization region cavity and a chemical ionization region cavity; ultraviolet light emitted by an ultraviolet light source penetrates through the side wall surface of the photoionization region cavity and is emitted into the region where the ion repulsion electrode and the grid electrode are spaced from each other along the surface parallel to the grid electrode; an ion funnel reaction area electrode is arranged in the chemical ionization area cavity. The combined ion source is based on a single ultraviolet light source, reagent ions for chemical ionization are obtained by utilizing photoionization or photoelectron ionization, and relatively independent ionization region design is adopted, so that mutual interference between photoionization and chemical ionization is avoided, photoionization or chemical ionization of sample molecules is respectively realized, and the range of ionizable and detected samples is greatly widened.
An ion funnel and mass spectrometry detection system (patent number zl201610023503.x) invented by schlieren et al, comprising M ring electrodes with same outer diameter and coaxial equal spacing arrangement, the inner diameter of which is reduced from the 1 st ring electrode to the M ring electrode in turn, the ion funnel further comprising: the first direct current power supply and the second direct current power supply, the first radio frequency power supply to the Nth radio frequency power supply; the first direct current power supply and the second direct current power supply are respectively connected to the first annular electrode and the Mth annular electrode and connect the M electrodes in series through a divider resistor; the first radio frequency power supply is connected with the 1 st, 1+ N and 1+2N … … th annular electrodes in parallel; the second radio frequency power supply is connected with the 2 nd, the 2 nd + N and the 2+2N … … th annular electrodes in parallel; … …, respectively; the (N-1) radio frequency power supply is connected with the (N-1) th, the (N-1 + N) th and the (N-1 +2N … …) th annular electrodes in parallel; the Nth radio frequency power supply is connected with the Nth, the Nth + N and the N +2N … … th ring electrodes in parallel. The invention improves the transmission efficiency of ions, in particular to the transmission efficiency of ions with small mass number.
The invention discloses an ultraviolet light chemical ionization source based on an ion funnel (patent number ZL201611019684.5) invented by Lihai et al, which comprises an ionization source cavity, a vacuum ultraviolet lamp, an excitation electrode, a reagent gas sample inlet pipe, a repulsion electrode, a sample gas sample inlet pipe, an ion funnel and a differential electrode. The ionization source utilizes the excellent focusing performance of the ion funnel under the medium air pressure, improves the reaction sufficiency of reagent ions and sample molecules and the transmission efficiency of the sample ions, realizes the enhancement of the ionization efficiency of the vacuum ultraviolet photochemical ionization source, and can greatly improve the sensitivity of the instrument.
A vacuum ultraviolet light ionization source for high flux gas sample analysis invented by plum sea et al (patent number ZL201010567335.3), comprising an ionization source cavity and a vacuum ultraviolet light source; a gas inlet is formed in the top of the ionization source cavity, and a gas sample enters the ionization source cavity through the gas inlet; an ion extraction electrode, an ion funnel and a differential interface polar plate which are mutually spaced, coaxial and parallel are sequentially arranged in the ionization source cavity along the flowing direction of the gas sample; the vacuum ultraviolet light source is arranged on the side wall of the ionization source cavity, and the vacuum ultraviolet light emitted by the vacuum ultraviolet light source is parallel to the polar plates of the ion extraction electrode and penetrates through the mutually spaced regions between the polar plates to enter the through hole region of the ion extraction polar plate. The vacuum ultraviolet light ionization source can effectively improve the detection sensitivity of the whole mass spectrometer system, and has wide application prospect in the fields of high-throughput gas sample analysis and trace or ultra-trace detection of organic pollutants in the environment.
While the above patents concerning ion funnels have advantages, they are bulky, have numerous mounting parts, are complex to install, and require excessive adjustment to ensure proper alignment. Aiming at the problems of simplified and light structure, simple and concise installation and size reduction of an ionization source of a mass spectrometer, the invention ensures that the structural space of the mass spectrometer ionization source is small as possible, and simultaneously reduces the absolute size of a conventional ion funnel. The novel ion funnel device technology greatly reduces the space size, has the same function as a conventional ion funnel device in the using effect, and has wide application prospect in the simple and convenient and small structural design of a mass spectrometry instrument.
Disclosure of Invention
The invention provides an ion funnel device used in a mass spectrum ionization source, which comprises an ion funnel support table, an ion funnel pole piece, an insulating PEEK pad and a fastening nut, wherein the ion funnel support table is provided with six support rods around the central axis in a circle of 360 degrees. Ions are incident from the ion funnel pole piece with a large middle caliber along the central axis direction of the ion funnel and are emergent from the ion funnel pole piece with a small middle caliber, and all the ion funnel pole pieces are of a flat plate structure with a middle round hole and are placed in parallel, coaxially and in an insulating mode.
An ion funnel device for a mass spectrometry ionization source comprises an ion funnel supporting table with six supporting rods around the central axis for 360 degrees, wherein an ion funnel pole piece is sleeved in the six supporting rods on the ion funnel supporting table, the ion funnel pole piece is divided into three supporting arms around the central axis for 360 degrees by 120 degrees, each supporting arm is provided with a hole, and the three holes are sleeved in the three supporting rods on the six supporting rods on the ion funnel supporting table. The adjacent ion funnel pole pieces are separated by the insulation PEEK pad to ensure that the adjacent ion funnel pole pieces are placed in an insulation manner, and finally, the whole ion funnel pole pieces are fastened by the fastening nuts.
Furthermore, adjacent ion funnel pole pieces are sleeved into six support rods on the ion funnel support platform in a staggered mode, the ion funnel pole pieces and the ion funnel support platform are both of a structure with a through hole in the middle, and the ion funnel pole pieces and the ion funnel support platform are parallel, insulated and coaxially arranged.
Furthermore, the ion funnel pole piece is made of metal such as stainless steel or the like or a pole piece with a metal plated on the surface; the number of the pole pieces of the ion funnel pole piece is 18 or more than 18 even pole pieces; the aperture of the through hole of the ion funnel pole piece is 1-30 mm.
Further, uniform voltage along the axial direction is applied to the ion funnel pole pieces in sequence from high to low, and a transmission electric field with the size of 5-50V/cm is formed in the axial direction. Meanwhile, radio frequency voltages with different positive and negative and the same size are applied between the adjacent ion funnel pole pieces.
Furthermore, the vacuum degree of the ion funnel pole piece is maintained between 1Torr and 5 Torr.
Furthermore, the adjacent ion funnel pole pieces are separated by an insulating PEEK pad, and the diameter of a middle through hole of the insulating PEEK pad is the same as that of a support rod on the ion funnel support platform.
Furthermore, the middle through holes of the ion funnel pole pieces are sequentially reduced from large to small according to a certain rule, and funnel shapes are formed on the premise of ensuring coaxiality.
Has the advantages that: the ion funnel device is designed with the minimum size, aims to enable the structural space of a mass spectrum ionization source to be small and exquisite as much as possible, and reduces the absolute size of a conventional ion funnel while ensuring the effect of the ion funnel. The novel ion funnel device technology greatly reduces the space size, has the same function as a conventional ion funnel device in the using effect, and has wide application prospect in the simple and convenient and small structural design of a mass spectrometry instrument.
Drawings
FIG. 1 is a schematic diagram of an ion funnel apparatus for use in a mass spectrometry ionization source;
FIG. 2 is a schematic view of an ion funnel support table of an ion funnel apparatus for use in a mass spectrometry ionization source;
FIG. 3 is a schematic diagram of an ion funnel pole piece of an ion funnel device for use in a mass spectrometry ionization source.
In the figure: 1. ion funnel pole piece, 2, fastening nut, 3, insulating PEEK pad, 4, ion funnel brace table, 1.1, hole, 1.2, support arm, 1.3, through-hole, 4.1, bracing piece.
Detailed Description
The following non-limiting examples will allow one of ordinary skill in the art to more fully understand the present invention, but are not intended to limit the invention in any way.
As shown in fig. 1, 2 and 3, an ion funnel device for use in a mass spectrometry ionization source comprises an ion funnel support platform 4 with six support rods 4.1 surrounding a central axis for 360 degrees, an ion funnel pole piece 1 is sleeved in the six support rods 4.1 on the ion funnel support platform 4, the ion funnel pole piece 1 is divided into three support arms 1.2 surrounding the central axis for 360 degrees by 120 degrees, each support arm 1.2 is provided with a hole 1.1, and the three holes 1.1 are sleeved in three non-adjacent support rods on the six support rods 4.1 on the ion funnel support platform 4; adjacent ion funnel pole piece 1 is separated mutually by insulating PEEK pad 3 to guarantee insulating the placing between adjacent ion funnel pole piece 1, fasten whole ion funnel pole piece 1 by fastening nut 2 at last.
In the six spinal branch vaulting poles 4.1 on the ion funnel brace table 4 were emboliaed with crisscross mode to adjacent ion funnel pole piece 1, ion funnel pole piece 1 and ion funnel brace table 4 are the structure that the middle part was provided with through-hole 1.3 to be parallel, insulating, coaxial placing between ion funnel pole piece 1 and the ion funnel brace table 4.
The ion funnel pole piece 1 is made of metal or a pole piece with a metal plated surface; the number of the ion funnel pole pieces 1 is 18 or more than 18 even pole pieces; the aperture of the through hole 1.3 of the ion funnel pole piece 1 is 1-30 mm.
Applying uniform voltage along the axial direction on the ion funnel pole piece 1 according to the pole piece sequence from high to low, and forming a transmission electric field with the size of 5-50V/cm in the axial direction; meanwhile, radio frequency voltages which are different in positive and negative and same in size are applied between the adjacent ion funnel pole pieces 1.
The vacuum degree of the ion funnel pole piece 1 is maintained between 1Torr and 5 Torr.
The diameter of the middle through hole of the insulation PEEK pad 3 is the same as that of the support rod 4.1 on the ion funnel support platform 4.
The middle through hole 1.3 of the ion funnel pole piece 1 is reduced from large to small in sequence, and funnel shape is formed on the premise of ensuring coaxiality.

Claims (7)

1.一种用于质谱电离源中的离子漏斗装置,其特征在于:包括绕中心轴线360°一周带有六根支撑杆(4.1)的离子漏斗支撑台(4),离子漏斗支撑台(4)上的六根支撑杆(4.1)内套入离子漏斗极片(1),离子漏斗极片(1)绕中心轴线360°一周以120°分割成三个支撑膀(1.2),每个支撑膀(1.2)均开有孔洞(1.1),三个孔洞(1.1)套入离子漏斗支撑台(4)上的六根支撑杆(4.1)上的三根不相邻的支撑杆中;相邻的离子漏斗极片(1)之间由绝缘PEEK垫(3)相阻隔,以保证相邻的离子漏斗极片(1)之间绝缘放置,最后由紧固螺母(2)对整体离子漏斗极片(1)进行紧固。1. an ion funnel device for mass spectrometry ionization source, it is characterized in that: comprise the ion funnel support table (4) with six support rods (4.1) around the central axis 360 ° a week, the ion funnel support table (4) The six support rods (4.1) on the top are sleeved into the ion funnel pole piece (1), and the ion funnel pole piece (1) is divided into three support arms (1.2) at 120° around the central axis 360° a week, and each support arm (1.2). 1.2) There are holes (1.1), and the three holes (1.1) are inserted into three non-adjacent support rods on the six support rods (4.1) on the ion funnel support table (4); adjacent ion funnel poles The sheets (1) are separated by insulating PEEK pads (3) to ensure insulation placement between adjacent ion funnel pole pieces (1). Tighten. 2.根据权利要求1所述的质谱电离源中的离子漏斗装置,其特征在于:相邻的离子漏斗极片(1)是以交错模式进行套入离子漏斗支撑台(4)上的六根支撑杆(4.1)内,离子漏斗极片(1)和离子漏斗支撑台(4)均为中部设置有通孔(1.3)的结构,并且离子漏斗极片(1)和离子漏斗支撑台(4)之间均为平行、绝缘、同轴放置。2. The ion funnel device in the mass spectrometry ionization source according to claim 1, characterized in that: the adjacent ion funnel pole pieces (1) are carried out in a staggered pattern to be embedded in six supports on the ion funnel support table (4). In the rod (4.1), the ion funnel pole piece (1) and the ion funnel support table (4) are both structures in which a through hole (1.3) is provided in the middle, and the ion funnel pole piece (1) and the ion funnel support table (4) They are placed in parallel, insulated and coaxially. 3.根据权利要求1所述的质谱电离源中的离子漏斗装置,其特征在于:离子漏斗极片(1)材料为金属或表面镀有金属的极片;离子漏斗极片(1)的数量为18片或18片以上的双数极片;离子漏斗极片(1)的通孔(1.3)的孔径为1~30mm。3. The ion funnel device in the mass spectrometry ionization source according to claim 1, is characterized in that: the material of the ion funnel pole piece (1) is metal or the pole piece plated with metal on the surface; the quantity of the ion funnel pole piece (1) There are 18 or more double-numbered pole pieces; the diameter of the through hole (1.3) of the ion funnel pole piece (1) is 1-30 mm. 4.根据权利要求1所述的质谱电离源中的离子漏斗装置,其特征在于:离子漏斗极片(1)上按照从高到低的极片顺序施加沿轴向方向的均匀电压,并在轴线方向上形成大小为5~50V/cm的传输电场;同时相邻离子漏斗极片(1)之间施加不同正负、且大小相同的射频电压。4. The ion funnel device in the mass spectrometry ionization source according to claim 1, wherein the ion funnel pole piece (1) is applied with a uniform voltage along the axial direction according to the order of the pole pieces from high to low, and the A transmission electric field with a size of 5-50 V/cm is formed in the axial direction; meanwhile, radio frequency voltages with different positive and negative values and the same size are applied between adjacent ion funnel pole pieces (1). 5.根据权利要求1所述的质谱电离源中的离子漏斗装置,其特征在于:离子漏斗极片(1)所在真空度维持在1Torr~5Torr之间。5 . The ion funnel device in the mass spectrometry ionization source according to claim 1 , wherein the vacuum degree where the ion funnel pole pieces ( 1 ) are located is maintained between 1 Torr and 5 Torr. 6 . 6.根据权利要求1所述的质谱电离源中的离子漏斗装置,其特征在于:绝缘PEEK垫(3)中间通孔的直径与离子漏斗支撑台(4)上的支撑杆(4.1)直径相同。6. The ion funnel device in the mass spectrometry ionization source according to claim 1, wherein the diameter of the through hole in the middle of the insulating PEEK pad (3) is the same as the diameter of the support rod (4.1) on the ion funnel support table (4). . 7.根据权利要求1所述的质谱电离源中的离子漏斗装置,其特征在于:离子漏斗极片(1)的中间通孔(1.3)由大到小依次缩减,确保同轴的前提下形成漏斗状。7. The ion funnel device in the mass spectrometry ionization source according to claim 1, characterized in that: the middle through hole (1.3) of the ion funnel pole piece (1) is successively reduced from large to small, and is formed on the premise of ensuring coaxiality Funnel-shaped.
CN202011481404.9A 2020-12-15 2020-12-15 Ion funnel device for mass spectrum ionization source Pending CN112599403A (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113471054A (en) * 2021-06-02 2021-10-01 中国科学院化学研究所 Gridless ion funnel trap device and method and application thereof

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN108091539A (en) * 2016-11-21 2018-05-29 中国科学院大连化学物理研究所 A kind of ultraviolet light chemical ionization source based on ion funnel
CN207542195U (en) * 2017-11-21 2018-06-26 中国科学院大连化学物理研究所 A kind of spindle ion funnel
EP3550587A1 (en) * 2018-04-05 2019-10-09 Technische Universität München Partly sealed ion guide and ion beam deposition system

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN108091539A (en) * 2016-11-21 2018-05-29 中国科学院大连化学物理研究所 A kind of ultraviolet light chemical ionization source based on ion funnel
CN207542195U (en) * 2017-11-21 2018-06-26 中国科学院大连化学物理研究所 A kind of spindle ion funnel
EP3550587A1 (en) * 2018-04-05 2019-10-09 Technische Universität München Partly sealed ion guide and ion beam deposition system

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113471054A (en) * 2021-06-02 2021-10-01 中国科学院化学研究所 Gridless ion funnel trap device and method and application thereof
CN113471054B (en) * 2021-06-02 2022-08-30 中国科学院化学研究所 Gridless ion funnel trap device and method and application thereof

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