CN106206239B

CN106206239B - High-efficient combination formula atmospheric pressure ionization source

Info

Publication number: CN106206239B
Application number: CN201610855957.3A
Authority: CN
Inventors: 杨丽珍; 刘忠伟; 郭群; 王卫国
Original assignee: Beijing Institute of Graphic Communication
Current assignee: Beijing Institute of Graphic Communication
Priority date: 2016-09-27
Filing date: 2016-09-27
Publication date: 2020-06-30
Anticipated expiration: 2036-09-27
Also published as: CN106206239A

Abstract

The invention discloses a high-efficiency combined atmospheric pressure ionization source, a VUV lamp, a high-voltage electrode, a ground electrode and quartz glass are arranged in parallel, and is coaxial, the quartz glass is positioned between the high-voltage electrode and the ground electrode, the sample inlet and the mass spectrum sample inlet are respectively arranged at two ends of the ionization source cavity, the ground electrode close to one side of the VUV lamp is provided with a small hole, a sample enters an ionization region in the ionization source cavity through the sample inlet, the ionization of the sample is realized by the single photon ionization of the VUV lamp, and the light emitted by the VUV lamp irradiates the surface of a far high-voltage electrode after passing through a small hole on a ground electrode and quartz glass to generate photoelectrons, the photoelectrons are used as seed electrons, the discharge voltage of dielectric barrier discharge is reduced, the breakdown of gas at low voltage is realized to form plasma, and the VUV lamp is turned off after the discharge is stable. The invention has the advantages of simple structure, easy miniaturization, low cost, and accurate qualitative and quantitative determination.

Description

High-efficient combination formula atmospheric pressure ionization source

Technical Field

The invention relates to the technical field of analytical instruments, in particular to a high-efficiency combined atmospheric pressure ionization source.

Background

The mass spectrometry technology can realize the accurate mass detection of the compound and the fragment ions thereof, and realize the accurate qualitative and quantitative analysis of the compound molecules. It has the advantages of high sensitivity, high flux, good quantitative linearity, etc. The method is a commonly used detection means in a plurality of fields such as chemistry, medicines, materials, biology, medicine, environment, energy, food, criminal identification and the like.

Mass spectrometry systems typically include ionization sources, mass analyzers, ion transport systems, control systems, and vacuum systems, among others. The ionization source is used for gasifying and ionizing the substance to be detected to form gaseous ions, and the gaseous ions finally reach the detector through the analyzer to be detected. Commonly used ionization sources include Single Photon Ionization (SPI) electron bombardment ionization source (EI), chemical ionization source (CI), electrospray ionization source (ESI), atmospheric pressure chemical ionization source (APCI), matrix assisted laser desorption ionization source (M ALDI), inductively coupled plasma ionization source (ICPI). Among them, the ionization source based on single photon ionization is a soft ionization source, it avoids the generation of fragment ions, the spectrogram is easy to analyze, especially suitable for the ionization and analysis of complex system, and has received more and more attention in recent years. However, due to the contamination of the optical window, the signal attenuation is severe during the use process, which results in inaccurate quantitative analysis. And the atmospheric pressure chemical ionization source based on dielectric barrier discharge has the advantage of stable signal and plays an important role in quantitative analysis. However, the breakdown voltage of the discharge under atmospheric pressure is high, a bulky power supply system is required, miniaturization and portability of the instrument are not facilitated, and the device is difficult to use on site.

Disclosure of Invention

The invention aims to make up the defects of the prior art and provide a high-efficiency combined atmospheric pressure ionization source.

The invention is realized by the following technical scheme:

the utility model provides a high-efficient combination formula atmospheric pressure ionization source, is including ionization source cavity, VUV lamp, high voltage electrode, ground electrode, quartz glass, introduction port, mass spectrum introduction port, VUV lamp, high voltage electrode, ground electrode and quartz glass parallel arrangement, and coaxial, quartz glass be located between high voltage electrode and the ground electrode, introduction port and mass spectrum introduction port set up respectively at the both ends of ionization source cavity, it has the aperture to open on the ground electrode that is close to VUV lamp one side, the sample gets into the ionization region of ionization source cavity inside through the introduction port, utilizes the ionization of the single photon ionization of VUV lamp to realize the ionization of sample to get into the mass spectrum through mass spectrum introduction port and carry out qualitative analysis, the light that rethread VUV lamp sent shines behind aperture and the quartz glass on the ground electrode and produces photoelectron to the high voltage electrode surface of keeping away from, photoelectron is as seed electron, reduces the medium and blocks discharge's discharge voltage, and the breakdown of gas under low voltage is realized to form plasma, and the VUV lamp is turned off after the discharge is stable.

The quartz glass may be passed through vacuum ultraviolet light.

The voltage of dielectric barrier discharge is between 100V and 10000V; the frequency is 10Hz-100 MHz.

The invention has the advantages that: the invention combines VUV single photon ionization and atmospheric pressure chemical ionization, and can realize qualitative and qualitative analysis of volatile organic compounds; the VUV light is utilized to irradiate the surface of the metal electrode to generate photoelectrons, so that the breakdown voltage of atmospheric pressure chemical ionization can be obviously reduced, and the miniaturization and portability of a power supply system and an analytical instrument are facilitated. The invention has the advantages of simple structure, easy miniaturization, low cost, and accurate qualitative and quantitative determination.

Drawings

FIG. 1 is a schematic structural diagram of the present invention.

Detailed Description

As shown in figure 1, a high-efficiency combined atmospheric pressure ionization source comprises an ionization source cavity 1, a VUV lamp 2, a high-voltage electrode 3, a ground electrode 4, quartz glass 5, a sample inlet 6 and a mass spectrum sample inlet 7, wherein the VUV lamp 2, the high-voltage electrode 3, the ground electrode 4 and the quartz glass 5 are arranged in parallel and coaxially, the quartz glass 5 is positioned between the high-voltage electrode and the ground electrode, the sample inlet 6 and the mass spectrum sample inlet 7 are respectively arranged at two ends of the ionization source cavity 1, a small hole is formed in the ground electrode 4 close to one side of the VUV lamp 2, a sample enters an ionization region 8 in the ionization source cavity 1 through the sample inlet 6, ionization of the sample is realized by single photon ionization of the VUV lamp 2, the sample enters a mass spectrum through the mass spectrum sample inlet 7 for qualitative analysis, and light emitted by the VUV lamp 2 irradiates the surface of the far-away high-voltage electrode after passing through the small hole in the ground electrode 4 and the quartz glass 5 to generate, photoelectrons are used as seed electrons, the discharge voltage of dielectric barrier discharge is reduced, the breakdown of gas at low voltage is realized to form plasma, and the VUV lamp is turned off after discharge is stable.

The quartz glass 5 may be passed through vacuum ultraviolet light.

The photon energy is greater than 8 eV.

The working principle of the invention is as follows:

firstly, when qualitative analysis is required, a sample enters an ionization region 8 through a sample inlet 6, ionization of the sample is realized by single photon ionization emitted by a VUV lamp 2, and the sample enters a mass spectrum for analysis through a mass spectrum sample inlet 7; then carrying out quantitative analysis, irradiating the surface of the electrode with photons generated by a VUV lamp to generate photoelectrons which are used as seed electrons, effectively reducing the discharge voltage of dielectric barrier discharge, and realizing the breakdown of gas at low voltage to form plasma; turning off the VUV lamp after the discharge is stable; the sample enters an ionization region 8 through a sample inlet 6, and the quantitative analysis of the sample is realized by using metastable molecules, atoms and the like generated by dielectric barrier discharge.

Claims

1. An efficient combined atmospheric pressure ionization source is characterized in that: the ionization source comprises an ionization source cavity, a VUV lamp, a high-voltage electrode, a ground electrode, quartz glass, a sample inlet and a mass spectrum sample inlet, wherein the VUV lamp, the high-voltage electrode, the ground electrode and the quartz glass are arranged in parallel and are coaxial, the quartz glass is arranged between the high-voltage electrode and the ground electrode, the sample inlet and the mass spectrum sample inlet are respectively arranged at two ends of the ionization source cavity, a small hole is formed in the ground electrode close to one side of the VUV lamp, a sample enters an ionization area in the ionization source cavity through the sample inlet, ionization of the sample is realized by single photon ionization of the VUV lamp, the sample enters a mass spectrum through the mass spectrum sample inlet for qualitative analysis, light emitted by the VUV lamp irradiates the surface of the high-voltage electrode far away after passing through the small hole in the ground electrode and the quartz glass to generate photoelectrons, the photoelectrons serve as seed electrons, discharge voltage of dielectric barrier discharge is reduced, and, the VUV lamp is turned off after the discharge has stabilized.

2. The high efficiency combined atmospheric pressure ionization source of claim 1, wherein: the quartz glass may be passed through vacuum ultraviolet light.

3. The high efficiency combined atmospheric pressure ionization source of claim 1, wherein: the voltage of dielectric barrier discharge is between 100V and 10000V; the frequency is 10Hz-100 MHz.