阅读说明：本技术 光电子抑制电离源装置 (Photoelectron-inhibiting ionization source device ) 是由 李海洋 曹艺雪 陈平 文宇轩 陈懿 于 2021-08-27 设计创作，主要内容包括：本发明属于质谱离子源技术领域,特别涉及一种光电子抑制电离源装置。包括紫外光源、传输电极、出口电极及绝缘挡光装置,其中传输电极和出口电极的轴向开有通孔,出口电极设置于传输电极的底部,紫外光源设置于传输电极的顶部通孔处,传输电极用于离子传输,出口电极用于真空差分；绝缘挡光装置用于间隔传输电极和出口电极及用于遮挡紫外光源的紫外光对传输电极和出口电极的辐照。本发明不仅可以抑制光电子产生,保证单一的单光子电离途径,还能够能实现离子聚焦,提高离子传输效率,有效提高样品测定动态区间。(The invention belongs to the technical field of mass spectrum ion sources, and particularly relates to a photoelectron suppression ionization source device. The device comprises an ultraviolet light source, a transmission electrode, an outlet electrode and an insulating light blocking device, wherein through holes are axially formed in the transmission electrode and the outlet electrode, the outlet electrode is arranged at the bottom of the transmission electrode, the ultraviolet light source is arranged at the through hole in the top of the transmission electrode, the transmission electrode is used for ion transmission, and the outlet electrode is used for vacuum difference; the insulating light blocking device is used for separating the transmission electrode from the outlet electrode and blocking the ultraviolet light of the ultraviolet light source from irradiating the transmission electrode and the outlet electrode. The invention can inhibit photoelectron generation, ensure single photon ionization path, realize ion focusing, improve ion transmission efficiency and effectively improve dynamic range of sample measurement.)

1. A photoelectron inhibition ionization source device is characterized by comprising an ultraviolet light source (1), a transmission electrode, an outlet electrode (9) and an insulation light blocking device, wherein through holes are axially formed in the transmission electrode and the outlet electrode (9), the outlet electrode (9) is arranged at the bottom of the transmission electrode, the ultraviolet light source (1) is arranged at the through hole in the top of the transmission electrode, the transmission electrode is used for ion transmission, and the outlet electrode (9) is used for vacuum difference;

the insulating light blocking device is used for separating the transmission electrode and the outlet electrode (9) and blocking the ultraviolet light of the ultraviolet light source (1) from irradiating the transmission electrode and the outlet electrode (9).

2. A photoelectron suppression ionization source device according to claim 1, wherein the transmission electrode comprises a top cover electrode (3), an inlet electrode (5) and a multi-pole electrode (7), wherein the top cover electrode (3) is arranged above the inlet electrode (5), the multi-pole electrode (7) is arranged circumferentially below the inlet electrode (5), and the axis is parallel to the transmission direction of the transmission electrode.

3. The photoelectron suppression ionization source device according to claim 2, wherein the light blocking device comprises a top cover electrode light blocking insulating pad (2), an inlet electrode insulating pad (4), a multi-pole rod electrode insulating pad (6) and a light blocking tube (8), wherein the top cover electrode light blocking insulating pad (2) is arranged between the ultraviolet light source (1) and the top cover electrode (3) and is used for blocking the irradiation of ultraviolet light of the ultraviolet light source (1) to the top cover electrode (3); the inlet electrode insulating pad (4) is arranged between the top cover electrode (3) and the inlet electrode (5) and is used for blocking the irradiation of ultraviolet light of the ultraviolet light source (1) to the inlet electrode (5); the light blocking tube (8) is arranged on the inner side of the multi-pole rod electrode (7) and used for blocking the ultraviolet light of the ultraviolet light source (1) from irradiating the multi-pole rod electrode (7).

4. The photoelectron suppression ionization source device according to claim 3, wherein the top cover electrode light-blocking insulating pad (2), the inlet electrode insulating pad (4) and the multi-pole rod electrode insulating pad (6) are all in an annular structure, and the diameter of an inner hole of the top cover electrode light-blocking insulating pad (2) is smaller than that of a through hole on the top cover electrode (3); the diameter of an inner hole of the inlet electrode insulating pad (4) is smaller than that of a through hole on the inlet electrode (5).

5. A photoelectron suppression ionization source device according to claim 3, wherein the light blocking tube (8) is provided with a bottom through hole; the diameter of the bottom through hole of the light blocking pipe (8) is smaller than that of the through hole on the outlet electrode (9).

6. A photoelectron suppression ionization source device according to claim 3, wherein the bottom of the light blocking tube (8) is provided with an extension radially outward, the extension being located between the multipole electrode (7) and the outlet electrode (9).

7. The photoelectron suppression ionization source device according to claim 3, wherein the top cover electrode light blocking insulating pad (2), the inlet electrode insulating pad (4) and the multipole electrode insulating pad (6) are PEEK insulating pads.

8. A photoelectron suppression ionization source device according to claim 3, wherein the top of the top cap electrode (3) is provided with a groove in which the top cap electrode light blocking insulating pad (2) is accommodated.

9. The photoelectron suppression ionization source device according to claim 2, wherein a sample injection capillary (10) is provided on the top cover electrode (3), and a sample injection end of the sample injection capillary (10) is located in an ionization region inside the transmission electrode.

10. The photoelectron suppression ionization source device according to claim 2, wherein a dc transmission voltage is applied to the top cover electrode (3) and the inlet electrode (5); radio frequency voltage is superposed on the multi-pole rod electrode (7) to realize the focusing transmission of ions.

Technical Field

The invention belongs to the technical field of mass spectrum ion sources, and particularly relates to a photoelectron suppression ionization source device.

Background

The vacuum ultraviolet light can enable organic molecules with ionization energy lower than photon energy to generate single photon ionization, mainly generates molecular ions, almost has no fragment ions, has simple spectrogram, can carry out rapid qualitative and quantitative analysis according to the molecular weight and the signal intensity, but only can ionize the molecules with ionization energy lower than the photon energy, and has limited range of analyzable substances. Photoelectrons generated in the reagent zone by using a vacuum ultraviolet light source can be developed into different ionization sources, such as: photoelectron ionization sources, single photon-chemical ionization and radio frequency electric field enhanced single photon-chemical ionization sources. The ionization range of the analyte can be enlarged by regulating and controlling the electron energy, and the ionization efficiency is improved. However, photoelectrons induce other ionization pathways than photoionization by the action of an electric field, such as: ionization bombardment ionization, chemical ionization, etc., and the existence of multiple ionization modes narrows the linear dynamic range of sample measurement. In addition, photoionization at high gas pressure causes sensitivity to be lowered due to a decrease in ion transfer efficiency.

Disclosure of Invention

In view of the above problems, the present invention provides a photoelectron-suppression ionization source device to solve the problems of the prior ionization technology that ionization approaches other than photoionization are generated, so that the linear dynamic range of sample measurement is narrowed, and the sensitivity of photoionization under high pressure is reduced due to the reduction of ion transmission efficiency.

In order to achieve the purpose, the invention adopts the following technical scheme:

a photoelectron inhibition ionization source device comprises an ultraviolet light source, a transmission electrode, an outlet electrode and an insulation light blocking device, wherein through holes are axially formed in the transmission electrode and the outlet electrode;

the insulating light blocking device is used for separating the transmission electrode from the outlet electrode and blocking the ultraviolet light of the ultraviolet light source from irradiating the transmission electrode and the outlet electrode.

The transmission electrode comprises a top cover electrode, an inlet electrode and a multi-pole rod electrode, wherein the top cover electrode is arranged above the inlet electrode, the multi-pole rod electrode is circumferentially arranged below the inlet electrode, and the axis of the multi-pole rod electrode is parallel to the transmission direction of the transmission electrode.

The light blocking device comprises a top cover electrode light blocking insulating pad, an inlet electrode insulating pad, a multi-pole rod electrode insulating pad and a light blocking tube, wherein the top cover electrode light blocking insulating pad is arranged between the ultraviolet light source and the top cover electrode and is used for blocking the irradiation of ultraviolet light of the ultraviolet light source on the top cover electrode; the inlet electrode insulating pad is arranged between the top cover electrode and the inlet electrode and used for blocking the irradiation of ultraviolet light of the ultraviolet light source to the inlet electrode; the light blocking tube is arranged on the inner side of the multi-pole rod electrode and used for blocking the irradiation of ultraviolet light of the ultraviolet light source to the multi-pole rod electrode.

The top cover electrode light-blocking insulating pad, the inlet electrode insulating pad and the multi-pole rod electrode insulating pad are all of annular structures, and the diameter of an inner hole of the top cover electrode light-blocking insulating pad is smaller than that of a through hole in the top cover electrode; the diameter of an inner hole of the inlet electrode insulating pad is smaller than that of a through hole on the inlet electrode.

The light blocking pipe is provided with a bottom through hole; the diameter of the bottom through hole of the light blocking pipe is smaller than that of the through hole on the outlet electrode.

The bottom of the light blocking pipe is provided with an extension part outwards along the radial direction, and the extension part is positioned between the multi-pole rod electrode and the outlet electrode.

And the top cover electrode light blocking insulating pad, the inlet electrode insulating pad and the multi-pole rod electrode insulating pad are PEEK insulating pads.

The top of the top cover electrode is provided with a groove, and the top cover electrode light blocking insulating pad is accommodated in the groove.

And the top cover electrode is provided with a sample injection capillary, and the sample injection end of the sample injection capillary is positioned in the ionization region at the inner side of the transmission electrode.

A direct current transmission voltage is applied to the top cover electrode and the inlet electrode; radio frequency voltage is superposed on the multi-pole rod electrode to realize the focusing transmission of ions.

The invention has the advantages and beneficial effects that: the photoelectron-inhibiting ionization source device provided by the invention can inhibit photoelectron generation, ensure a single photon ionization path, realize ion focusing, improve ion transmission efficiency and effectively improve a sample measurement dynamic interval.

Drawings

FIG. 1 is a schematic structural diagram of an apparatus for photoelectron suppression ionization source according to an embodiment of the present invention;

in the figure: 1. ultraviolet light source, 2, top cover electrode light-blocking insulating pad, 3, top cover electrode, 4, inlet electrode insulating pad, 5, inlet electrode, 6, multi-pole electrode insulating pad, 7, multi-pole electrode, 8, light-blocking tube, 9, outlet electrode, 10 and sample injection capillary tube.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention will be described in detail with reference to the accompanying drawings and specific embodiments.

As shown in fig. 1, the photoelectron-suppression ionization source device provided by the present invention comprises an ultraviolet light source 1, a transmission electrode, an outlet electrode 9 and an insulating light blocking device, wherein through holes are axially formed on the transmission electrode and the outlet electrode 9, the outlet electrode 9 is disposed at the bottom of the transmission electrode, the ultraviolet light source 1 is disposed at the through hole at the top of the transmission electrode, the transmission electrode is used for ion transmission, and the outlet electrode 9 is used for vacuum differential; the insulating light blocking device is used for separating the transmission electrode and the outlet electrode 9 and blocking the ultraviolet light of the ultraviolet light source 1 from irradiating the transmission electrode and the outlet electrode 9.

In the embodiment of the present invention, the transmission electrode includes a top cover electrode 3, an inlet electrode 5 and a multi-pole electrode 7, wherein the top cover electrode 3 is disposed above the inlet electrode 5, the multi-pole electrode 7 is circumferentially disposed below the inlet electrode 5, and the axis is parallel to the transmission direction of the transmission electrode. The light blocking device comprises a top cover electrode light blocking insulating pad 2, an inlet electrode insulating pad 4, a multi-pole rod electrode insulating pad 6 and a light blocking tube 8, wherein the top cover electrode light blocking insulating pad 2 is arranged between the ultraviolet light source 1 and the top cover electrode 3 and is used for blocking the irradiation of ultraviolet light of the ultraviolet light source 1 to the top cover electrode 3; the inlet electrode insulating pad 4 is arranged between the top cover electrode 3 and the inlet electrode 5 and is used for blocking the irradiation of ultraviolet light of the ultraviolet light source 1 to the inlet electrode 5; the light blocking tube 8 is arranged on the inner side of the multi-pole electrode 7 and used for blocking the ultraviolet light of the ultraviolet light source 1 from irradiating the multi-pole electrode 7.

Specifically, the top cover electrode light-blocking insulating pad 2, the inlet electrode insulating pad 4 and the multi-pole rod electrode insulating pad 6 are all of annular structures, and the diameter of an inner hole of the top cover electrode light-blocking insulating pad 2 is smaller than that of a through hole in the top cover electrode 3; the diameter of the inner hole of the inlet electrode insulating pad 4 is smaller than the diameter of the through hole on the inlet electrode 5. The light blocking pipe 8 is provided with a bottom through hole; the diameter of the bottom through hole of the light blocking tube 8 is smaller than that of the through hole on the outlet electrode 9.

Further, the bottom of the light-blocking tube 8 is provided with an extension radially outwards, which is located between the multipole electrode 7 and the outlet electrode 9.

Further, the top cover electrode light-blocking insulating pad 2, the inlet electrode insulating pad 4 and the multi-pole electrode insulating pad 6 are PEEK insulating pads.

In the embodiment of the invention, the top cover electrode 3 is a metal electrode provided with a circular hole, the top of the top cover electrode 3 is provided with a groove, the top cover electrode light-blocking insulating pad 2 is accommodated in the groove, and the ultraviolet light source 1 is positioned right above the top cover electrode light-blocking insulating pad 2. The top cover electrode 3 is provided with a sample introduction capillary tube 10, the sample introduction end of the sample introduction capillary tube 10 is positioned in an ionization region at the inner side of the transmission electrode, the sample introduction capillary tube 10 introduces a gas sample into the vacuum ultraviolet lamp from one side of the ionization chamber for ionization, and the sample introduction direction of the gas sample is vertical to the optical axis of the ultraviolet light source 1.

In the embodiment of the invention, direct current transmission voltage is applied to the top cover electrode 3 and the inlet electrode 5; radio frequency voltage is superposed on the multi-pole electrode 7 to realize the focusing transmission of ions. The ultraviolet light source 1 is a direct current vacuum ultraviolet lamp for generating ultraviolet light. Ultraviolet light belongs to the category of photons, when photons enter a material, the photons interact with target atoms according to different photon energies, and when the energy of the incident photons is less than 1MeV, the photons are mainly in the photoelectric effect, namely, the incident photons are absorbed by the target atoms and then collide to generate a free electron, which is called as photoelectron. The source that causes the other ionization processes is photoelectrons generated by the photoelectric effect. Photoelectrons are accelerated to form high-energy photoelectrons under the action of a direct-current electric field and a radio-frequency electric field, the high-energy photoelectrons can directly bombard sample molecules to ionize the sample molecules, and can collide with background gas to generate actual ions such as oxygen ions and the like, and the generated ions collide with the sample molecules to ionize, namely a chemical ionization process. The above processes occur depending on the number of photoelectrons generated in the photoelectric effect, and the less the number of photoelectrons, the lower the probability that non-photoionization processes occur.

The invention provides a photoelectron suppression ionization source device, which is characterized in that an ultraviolet light source 1, a top cover electrode light blocking insulating pad 2, a top cover electrode 3, an inlet electrode insulating pad 4, an inlet electrode 5, a multi-pole electrode insulating pad 6, a light blocking tube 8 and an outlet electrode 9 are coaxially arranged in sequence, and four multi-pole electrode 7 are uniformly distributed on the outer side of the light blocking tube 8 along the circumferential direction. Ultraviolet light of the ultraviolet light source 1 enters an ionization region, wherein the top cover electrode light blocking insulating pad 2 is used for blocking the irradiation of the ultraviolet light source 1 on the top cover electrode 3, and the inlet electrode insulating pad 4 is used for irradiation of the ultraviolet light source 1 on the inlet electrode 5. Through the design, the generation of photoelectrons is effectively inhibited, the focusing transmission of ions is realized, and the dynamic range of sample determination is further improved.

The invention can effectively inhibit the quantity of photoelectrons emitted on the surface of the equipment structural member in the ultraviolet light source irradiation system, avoids other ionization ways caused by the photoelectrons, ensures that only a photoionization process exists in an ionization source, and effectively improves the linear range of sample measurement by using the radio frequency multipole rod for focused ion transmission.

The above description is only an embodiment of the present invention, and is not intended to limit the scope of the present invention. Any modification, equivalent replacement, improvement, extension, etc. made within the spirit and principle of the present invention are included in the protection scope of the present invention.