Raman-LIBS-mass spectrum combined analysis device and analysis method

Abstract

The invention belongs to the technical field of chemical detection, and particularly relates to a Raman-LIBS-mass spectrometry combined analysis device and analysis method.The Raman-LIBS-mass spectrometry combined analysis device comprises a multiple reflection time-of-flight mass spectrometer, an LIBS spectrometer, a Raman spectrometer and a common module; the common module comprises a first incident light path system, a second incident light path system, a high-definition observation system, a vacuum sample bin, a vacuum system and a control system; the first incident light path system is used for generating a femtosecond laser beam and performing three-dimensional denudation on a sample; and the second incident light path system is used for combining the tunable laser into a resonant ionization light path. Compared with the prior art, in-situ micro-area ultrahigh-resolution element and isotope analysis and imaging can be achieved, ultra-trace element and isotope analysis and isotope ratio analysis under strong matrix interference are achieved, and meanwhile high-resolution molecular structure and composition analysis and Raman scattering imaging can be conducted.

Description

Technical Field

[0001] The present invention belongs to the technical field of chemical detection, and in particular relates to a Raman-LIBS-mass spectrometry analysis device and an analysis method. Background Art

[0002] Isotope technology is used in medical research for metabolic studies, nutritional research, and disease diagnosis. In recent years, its application in environmental science has gained increasing attention. The use of stable isotope abundance variations to study and indicate the sources and extent of environmental pollution is of great significance in environmental protection efforts. Laser-induced breakdown spectroscopy (LIBS) and other spectrometers can rapidly detect isotopes, but they suffer from low sensitivity and limited resolution, potentially insufficient for isotopes with very similar masses. Stable isotope analysis is performed using gaseous mass spectrometry, often referred to as gas mass spectrometers.

[0003] Before conducting isotope analysis, the sample must be prepared to a state suitable for analysis. Mass spectrometers using inductively coupled plasma (ICP) as an ionization source (such as ICP-MS, MC-ICP-MS, and ICP-TOF-MS) are currently fundamental instruments for isotope detection. However, they still require complex sample pretreatment. The introduction of strong acids and other substances during pretreatment can cause sample contamination and damage the sample's original state and structure. Furthermore, while ICP source technology is mature and stable, the efficiency of plasma transmission to the skimmer cone after the ICP source generates it is low. All of these factors can significantly complicate the analysis of samples, especially low-abundance samples such as young geological samples, and can affect test results.

[0004] LA-ICP-MS (laser ablation inductively coupled plasma mass spectrometry) is a laser ablation superposition inductively coupled plasma mass spectrometer that solves the problem of solid sample processing and enables in situ microanalysis. However, due to the small sample volume and low ion transmission efficiency of traditional laser ablation, the detection of low-abundance isotopes is also difficult. Furthermore, researchers in related fields not only want to determine the elemental and isotopic content of samples, but also analyze their molecular structure and composition.

[0005] Current element and isotope detection technologies have the following limitations: traditional liquid detection methods require tedious sample pretreatment, and the introduction of strong acids and other pollutants destroys the original state and structure of the sample, affecting the accuracy of detection. In addition, in-situ micro-area detection cannot be achieved, and the result is only an average value; stable isotope analysis (such as C, H, O, N, S) requires the sample to be converted into gas form for mass spectrometry analysis, which limits the range of detected elements; the isotope abundance is extremely low and the difference is small, and there are problems of isotope fractionation and background interference in the detection, which relies on high-sensitivity instruments and method optimization; the ion transmission efficiency of inductively coupled plasma mass spectrometer (ICP-MS) is low, resulting in limited detection limits; traditional laser induced breakdown spectroscopy (LIBS) is affected by self-absorption effects, matrix effects and spectral fluctuations, and has the defects of low detection limit, poor sensitivity and insufficient analytical accuracy; mass spectrometers have difficulty in detecting light elements and major elements; traditional LIBS cannot cover trace elements; the mass resolution of quadrupole mass spectrometry is only 400~500 Th / Th; Traditional Raman spectroscopy technology uses traditional nanosecond laser light sources, resulting in weak signals. It lacks sensitivity in the analysis of low-concentration, trace and trace substances, making it difficult to obtain effective molecular structure information. Summary of the Invention

[0006] (1) Technical issues to be resolved The purpose of the present invention is to solve at least one of the above problems and to provide a Raman-LIBS-mass spectrometry analysis device and analysis method, which integrates a three-dimensional femtosecond laser ablation laser resonance ionization multiple reflection time-of-flight mass spectrometer, a femtosecond multi-pulse laser induced breakdown enhancement spectroscopy (LIBS) and a Raman spectrometer to solve the problem of isobaric interference in the existing technology, and can realize ultra-trace element, isotope analysis and isotope ratio analysis under strong matrix interference, realize in situ micro-area ultra-high resolution element and isotope analysis and imaging, and can simultaneously perform high-resolution molecular structure and composition analysis and Raman scattering imaging. It has a compact structure, advanced technology and high analysis efficiency.

[0007] (2) Technical solution The purpose of the present invention is achieved through the following technical solutions: The first aspect of the present invention discloses a Raman-LIBS-mass spectrometry analysis device, comprising a multiple reflection time-of-flight mass spectrometer, a LIBS spectrometer, a Raman spectrometer, and a common module; The shared module includes a first incident light path system, a second incident light path system, a high-definition observation system, a vacuum sample chamber, a vacuum system and a control system; The first incident light path system includes a first laser source, a light path shaping component, and a three-dimensional scanning focusing device arranged in sequence, for generating a femtosecond laser beam and performing three-dimensional ablation on the sample; The second incident light path system includes a second laser source, an independent light path control unit, a light path merging component and a focusing unit arranged in sequence, and is used to merge the tunable laser into a resonant ionization light path; The multiple reflection time-of-flight mass spectrometer is used to analyze the content of each element and isotope in the sample and perform element imaging; The LIBS spectrometer and Raman spectrometer collect spectral signals through optical fibers and spectrometers respectively, analyze the molecular structure and composition of the sample, and perform Raman scattering imaging; The multiple reflection time-of-flight mass spectrometer and the LIBS spectrometer share a first incident light path system and a second incident light path system, and the Raman spectrometer uses the first incident light path system as a laser source.

[0008] Furthermore, the control system is mainly composed of a computing workstation, communication modules of various components, various sensors, vacuum gauges, signal control panels, etc., which collect and process information data and issue control instructions to control the coordinated work of various components.

[0009] Furthermore, the second incident optical path system is provided with a plurality of second laser sources, the second laser sources are configured as tunable lasers, and the wavelength tuning range of the tunable lasers is 210 nm to 4500 nm; The independent optical path control unit corresponds to the second laser source one by one, and includes an attenuator and a beam expander arranged in sequence; The optical path merging component includes a reflector and a beam combiner, which is used to merge multiple laser beams into a single optical path; The focusing unit includes a window and a focusing lens, which focuses the combined laser light onto the sample ablation area.

[0010] After the lasers of the plurality of second laser sources pass through their respective independent optical path control units, they are merged into a second single optical path through an optical path merging component, and the second single optical path enters the vacuum sample chamber through a focusing unit.

[0011] Furthermore, the working quantity of the second laser source can be dynamically adjusted by a control system and selectively combined and triggered according to the ionization requirements of the target element.

[0012] The number of tunable lasers in the second laser source system of the second incident optical path is preferably three. The tunable laser can achieve a wide tuning range of 210 nm to 4500 nm wavelength from ultraviolet to mid-infrared, as well as high output stability. Since different elements or isotopes have different atomic energy levels, it is necessary to set the appropriate laser wavelength, frequency, and energy value for each tunable laser according to the element or isotope to be measured to resonate the energy of the laser photon with the electron energy level of the target molecule, thereby achieving selective ionization of the substance and enhancing the ionization efficiency of the target atoms. According to the target element to be measured, the triggering of the three tunable lasers and the wavelength of their respective output lasers are controlled by the control system.

[0013] Furthermore, when the second incident light path system is activated, at least one second laser source is selected to operate.

[0014] Furthermore, the high-definition observation system is a coaxial observation system, which is mainly composed of a camera, a lens barrel, a beam combiner and an objective lens, and shares an objective lens with the first incident light path system. The high-definition observation system is used to observe the sample position, sample status and the conditions inside the vacuum cell when analyzing the sample.

[0015] Furthermore, the vacuum sample chamber includes a three-axis nano-moving stage, a sample holder, and a temperature control stage, and the vacuum sample chamber is a fully sealed design; The three-axis nanometer moving stage is installed on the base of the vacuum sample chamber. It is a three-axis nanometer vacuum moving stage with a resolution of less than or equal to 10nm and a repeatability accuracy of less than or equal to 300nm. The temperature control table is used to precisely control the temperature of the sample with an accuracy of 0.1 degrees Celsius; The sample holder is used to place and fix the sample.

[0016] Furthermore, the multiple reflection time-of-flight mass spectrometer is configured as a three-dimensional femtosecond laser ablation laser resonance ionization multiple reflection time-of-flight mass spectrometer, including an interface, an ion transmission system, a multiple reflection time-of-flight mass analyzer and a detector, and the first incident light path system and the second incident light path system generate an ion source of the three-dimensional femtosecond laser ablation laser resonance ionization multiple reflection time-of-flight mass spectrometer; The ion transmission system includes an ion funnel, a bent quadrupole, a notch filter, a 90-degree deflection lens and an ion shaping module.

[0017] The function of the bent quadrupole is to act as an ion guide while removing neutral particles to achieve ion beam purification.

[0018] Notch filters are used to selectively remove target ions with a specific mass-to-charge ratio (m / z) from an ion beam containing multiple ions, and can selectively filter out high-abundance interfering ions.

[0019] The function of the 90-degree deflection lens is to use the electrostatic field to precisely deflect the ion beam by 90 degrees, while achieving energy focusing and directional focusing of the ions in the process, thereby significantly improving the resolution of the instrument.

[0020] The ion shaping module optimizes the spatial distribution of the ion beam and improves the resolution of the multi-reflection time-of-flight mass analyzer.

[0021] The multi-reflection time-of-flight mass analyzer (MRTOF) of a multi-reflection time-of-flight mass spectrometer (MTFMS) is an electrostatic ion beam trap consisting of two symmetrical ion reflection lens groups and a pulse drift region in between. While conventional reflectron-type TOFMSs only reflect the ion beam once in the reflection region, the MRTOFMS structure of the present invention features two reflection regions at either end of the flight zone. Upon entering the flight zone, the ion beam raises the potential of these two reflection regions, preventing the ions from passing through and forcing them back into the flight zone. Furthermore, the ions undergo multiple reciprocating reflections between the two reflection regions, extending their actual flight distance.

[0022] Based on the above-mentioned multiple reflection time-of-flight mass spectrometer structure, the mass resolution of the intrinsic mass spectrometer can reach 100,000Th / Th, realizing high-precision measurement of Li~U element isotope ratios. At the same time, due to its strong anti-interference ability, the intrinsic mass spectrometer can perform high-precision detection of complex matrices.

[0023] Furthermore, the vacuum of the three-dimensional femtosecond laser ablation laser resonance ionization multiple reflection time-of-flight mass spectrometer is achieved through the vacuum system of the Raman-LIBS-mass spectrometry analysis device, and data acquisition, processing and control are achieved through the control system of the Raman-LIBS-mass spectrometry analysis device.

[0024] Furthermore, a femtosecond laser is provided as the first laser source in the first incident optical path system, wherein the wavelength of the femtosecond laser is ≤517 nm, the pulse width is <500 fs, and the repetition frequency is ≥500 kHz; The optical path shaping component includes a high-precision attenuator, a beam expander, a beam shaper and a reflector arranged in sequence, which are used to adjust the laser energy, beam size and spatial distribution. The high-precision attenuator can adjust the laser power from full power to milliwatt level; The three-dimensional scanning and focusing device integrates X-axis and Y-axis galvanometers and a Z-axis focusing module, and a beam combining mirror is arranged between the X / Y-axis galvanometers and the Z-axis focusing module; the two-axis scanning galvanometers (X-axis galvanometer, Y-axis galvanometer) and the focusing Z-axis in the three-dimensional scanning and focusing device can directly adopt a three-axis galvanometer system.

[0025] An objective lens is set at the end of the first incident light path system to focus the regulated laser onto the sample surface, generating plasma and neutral particle cloud.

[0026] Furthermore, the coordinated control of the first incident optical path system and the second incident optical path system satisfies: the delay time between the femtosecond ablation laser and the resonant ionization laser is less than 1 μs; the synchronization accuracy between multiple resonant ionization lasers reaches the nanosecond level and is controlled in real time by the control system.

[0027] The present invention employs a Raman-LIBS-mass spectrometry analysis method that involves a control system controlling the delay between multiple laser beams, including a laser beam emitted by a first incident optical path system for laser ablation and a laser beam emitted by a second incident optical path system for laser ionization. The delay between the laser ablation and laser ionization lasers is less than 1µs. To achieve efficient step-by-step resonant ionization, the time synchronization between the laser beams used for laser ionization must be in the nanosecond range. The specific time can be optimized through experimentation. A computer issues instructions to a signal control board, which in turn sends signals to each laser, which then emits the required laser light in response to the signals.

[0028] Furthermore, the vacuum system includes a mechanical vacuum pump and a turbomolecular pump; The vacuum system is a four-stage gradient vacuum system, with the first stage vacuum degree <300 Pa, achieved by a mechanical vacuum pump, the second stage vacuum degree <0.5 Pa, and the third stage vacuum degree <3*10 -3 Pa, fourth level vacuum degree <2*10 -4 Pa; the second to fourth stages of vacuum are achieved by mechanical vacuum pumps and turbomolecular pumps.

[0029] Furthermore, the first stage of the vacuum system, namely the vacuum pool, interface and ion funnel, uses a mechanical vacuum pump. A large amount of extracted gas is discharged at this stage, and the vacuum degree is required to be <300Pa; the second stage vacuum chamber equipped with an ion lens has a vacuum degree of <0.5Pa; the third stage is the ion guide module and the notch filter module, and the vacuum degree is <3*10 -3 Pa; the fourth stage is the multiple reflection time-of-flight mass analyzer and detector module, which requires a vacuum degree of <2*10 -4 The second to fourth stages of vacuum are achieved by a mechanical vacuum pump and a turbomolecular pump. That is, after the mechanical vacuum pump pre-evacuates, the turbomolecular pump is continuously operated to maintain the vacuum.

[0030] Furthermore, the multiple reflection time-of-flight mass spectrometer, LIBS spectrometer, and Raman spectrometer can work independently or simultaneously.

[0031] Furthermore, the LIBS spectrometer is configured as a femtosecond multi-pulse laser-induced breakdown enhancement spectrometer, which operates synchronously with the multiple-reflection time-of-flight mass spectrometer analysis. That is, the three-dimensional femtosecond laser ablation laser resonance ionization multiple-reflection time-of-flight mass spectrometer can simultaneously collect LIBS spectral signals during mass spectrometry analysis, thereby realizing complementary analysis of elemental composition under strong matrix interference.

[0032] Furthermore, a femtosecond multi-pulse laser-induced breakdown enhancement spectrometer, including a spectrum collection module, an optical fiber, a spectrometer and a LIBS spectrometer detector, is used to collect spectral signals and perform analysis; The Raman spectrometer comprises a collecting optical fiber, a filter, a grating or an interferometer and a Raman spectrometer detector, and is used to collect Raman scattering spectrum signals and perform analysis.

[0033] The second technical solution of the present invention is a Raman-LIBS-mass spectrometry analysis method, which is performed using the Raman-LIBS-mass spectrometry analysis device described above, and includes the following steps: S1: The system switches to Raman mode. The first incident light path system emits laser light to illuminate the sample to be tested. The Raman spectrometer performs molecular structure imaging to generate multi-dimensional analysis data. S2: The system in the same area is switched to mass spectrometer mode, and three-dimensional micro-area femtosecond laser ablation is performed through the first incident light path system; S3: Synchronously trigger the tunable laser of the second incident light path system to selectively ionize the target element / isotope; S4: The elemental / isotopic composition was analyzed by multiple reflection time-of-flight mass spectrometry and the elemental distribution was verified by LIBS spectrometry.

[0034] Furthermore, the analysis steps of the three-dimensional femtosecond laser ablation laser resonance ionization multiple reflection time-of-flight mass spectrometer are as follows: the femtosecond laser source of the first incident optical path system emits a laser, which is energy-attenuated, expanded and shaped by the optical path shaping component, and then the two-dimensional galvanometer scanning of the three-dimensional scanning and focusing device is superimposed on the Z-axis and the objective lens for precise focusing, so as to three-dimensionally laser ablate the selected sample area into plasma and neutral particle cloud; the second incident optical path system adjusts the tunable laser of the second laser source to a laser with a suitable wavelength for laser ionization of the target element to be measured, and the lasers emitted by the tunable lasers pass through their respective independent optical path control units, and are then merged into one optical path by the reflector and beam combiner in the optical path merging component, and finally the laser is focused onto the plasma and neutral particle cloud above the sample through the focusing lens, and several laser beams resonantly ionize the neutral particles into ions. The ion beam formed after ionization can enter the multiple reflection time-of-flight mass analyzer through the ion transmission system, and finally reach the ion detector for detection.

[0035] Furthermore, the analysis steps of the LIBS spectrometer are as follows: the femtosecond laser source of the first incident optical path system emits laser light, which is attenuated by the energy of the optical path shaping component, and after beam expansion and shaping, the selected sample area is three-dimensionally laser-ablated into plasma and neutral particle cloud through the two-dimensional galvanometer scanning superimposed on the Z-axis and precise focusing of the objective lens by the three-dimensional scanning and focusing device; the second incident optical path system adjusts the second laser source tunable laser to a laser with a wavelength suitable for laser ionization of the target element to be measured. The laser light emitted by the tunable laser passes through each independent optical path control unit and is then merged into one optical path by the reflector and beam combiner in the optical path merging component. Finally, the laser light is focused onto the plasma and neutral particle cloud above the sample through a focusing lens. Several laser beams enhance the ionization of the neutral particles into plasma. During the ionization process, light with a characteristic wavelength is emitted and enters the LIBS spectrometer through an optical fiber for analysis; the LIBS spectrometer determines the elemental composition and distribution of the sample by analyzing the wavelength and intensity of these spectra.

[0036] If the second incident light path system uses only one second laser source tunable laser to work, the LIBS spectrometer is a dual-pulse laser-induced breakdown enhancement spectrometer. If multiple second laser source tunable lasers are used, the LIBS spectrometer is a multi-pulse laser-induced breakdown enhancement spectrometer.

[0037] Furthermore, the analysis steps of the Raman spectrometer are as follows: first, the high-precision attenuator parameters are set according to the energy value required by the Raman spectrum to ensure that the final laser energy meets the requirements of the Raman spectrum; when working, the femtosecond laser source of the first incident light path system emits laser light, which is attenuated by the energy of the light path shaping component, and after beam expansion and shaping, the laser is focused on the selected sample area on the sample surface through the two-dimensional galvanometer scanning of the three-dimensional scanning and focusing device, superimposed on the Z axis and precise focusing of the objective lens. The scattered light emitted by the sample is collected and enters the Raman spectrometer through the optical fiber for analysis.

[0038] (3) Beneficial effects Compared with the prior art, the present invention has the following advantages: (1) The present invention integrates a three-dimensional femtosecond laser ablation laser resonance ionization multiple reflection time-of-flight mass spectrometer, a femtosecond multi-pulse laser induced breakdown enhancement spectrometer (LIBS spectrometer) and a Raman spectrometer. The three analysis function modules share the laser source, optical path system, high-definition observation system, vacuum sample chamber, vacuum system and control system. It combines the in-situ, micro-area and high sampling volume characteristics of three-dimensional laser ablation, the high element selectivity, isotope selectivity, high ion yield of three-dimensional laser resonance ionization and the high isotope resolution capability of multiple reflection time-of-flight mass analyzer, and can solve the problem of isobaric interference. It can not only realize ultra-trace element, isotope analysis and isotope ratio analysis under strong matrix interference, but also analyze the sample molecular structure and composition analysis and Raman scattering imaging.

[0039] (2) The three-dimensional femtosecond laser ablation laser resonance ionization multiple reflection time-of-flight mass spectrometer in the present invention uses a laser resonance ionization system as an ion source. The laser covers the neutral particle cloud after laser ablation. Multiple laser beams resonantly ionize the neutral particles into ions, which can achieve an ionization efficiency several orders of magnitude higher than that of traditional analysis, improve the sensitivity and detection limit of the equipment, and can detect ultra-trace elements or isotopes. The ions generated by laser resonance ionization are in a vacuum state, and there is no ion transmission loss, which greatly improves the transmission efficiency and sensitivity, and further reduces the matrix effect by removing the ion-ion space interaction.

[0040] (3) The multiple reflection time-of-flight mass spectrometer has ultra-high mass resolution and high sensitivity. The present invention adopts a three-dimensional femtosecond laser ablation laser resonance ionization multiple reflection time-of-flight mass spectrometer, which not only greatly improves the efficiency of laser ablation and the amount of sample ablation, but also improves the sensitivity and detection limit of the equipment. It also realizes the precise in-situ micro-area analysis of the sample, solves the problem of isobaric interference, and can realize the isotopic analysis of ultra-trace nuclides under strong matrix interference, which can meet the needs of high-precision isotope mass spectrometry analysis.

[0041] (4) The femtosecond multi-pulse laser-induced breakdown enhancement spectrometer (LIBS spectrometer) in this invention greatly increases the sample ablation amount, greatly prolongs the plasma life and greatly improves the plasma excitation ability, achieving 10 -7 The LIBS detection limit is increased by at least 2 orders of magnitude; at the same time, the Raman spectroscopy technology in the present invention adopts femtosecond laser to enhance the Raman scattering intensity, significantly improve the detection sensitivity, and break through the detection limitations of conventional technology. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0043] Figure 1 This is a schematic structural diagram of a Raman-LIBS-mass spectrometry analysis device according to the present invention; Figure 2 Schematic diagram of the principle of a three-dimensional femtosecond laser ablation laser resonance ionization multiple reflection time-of-flight mass spectrometer in a Raman-LIBS-mass spectrometry analysis device of the present invention; Figure 3This is a schematic structural diagram of a three-dimensional femtosecond laser ablation laser resonance ionization multiple reflection time-of-flight mass spectrometer in a Raman-LIBS-mass spectrometry analysis device of the present invention; Figure 4 Schematic diagram of the structure of a LIBS spectrometer in a Raman-LIBS-mass spectrometry analysis device of the present invention; Figure 5 The figure is a schematic structural diagram of a Raman spectrometer in a Raman-LIBS-mass spectrometry analysis device of the present invention.

[0044] In the figure: 1-multiple reflection time-of-flight mass spectrometer; 101-multiple reflection time-of-flight mass analyzer; 102-detector; 103-ion funnel; 104-bent quadrupole; 105-notch filter; 106-90 degree deflection lens; 107-ion shaping module; 2-LIBS spectrometer; 3-Raman spectrometer; 4-first incident light path system; 401-first laser source; 402-light path shaping component; 403-three-dimensional scanning focusing device; 404-objective lens; 5-second incident light path system; 501-second laser source; 502-independent light path control unit; 503-light path merging component; 504-focusing unit; 6-high-definition observation system; 7-vacuum sample chamber; 8-vacuum system; 801-mechanical vacuum pump; 802-turbomolecular pump. DETAILED DESCRIPTION

[0045] The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0046] The following describes the embodiments of the present application through specific examples, and those skilled in the art can easily understand other advantages and effects of the present application from the contents disclosed in this specification. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. The present application can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present application. It should be noted that, in the absence of conflict, the features in the following embodiments and embodiments can be combined with each other. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without making creative work are within the scope of protection of this application.

[0047] It should be noted that various aspects of the embodiments within the scope of the appended claims are described below. It should be apparent that the aspects described herein can be embodied in a wide variety of forms, and any specific structure and / or function described herein is merely illustrative. Based on this application, it should be understood by those skilled in the art that an aspect described herein can be implemented independently of any other aspect, and two or more of these aspects can be combined in various ways. For example, any number and aspect described herein can be used to implement an apparatus and / or practice a method. In addition, other structures and / or functionalities other than one or more of the aspects described herein can be used to implement this apparatus and / or practice this method.

[0048] It should also be noted that the illustrations provided in the following embodiments are only schematic illustrations of the basic concept of the present application. The illustrations only show components related to the present application and are not drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component can be changed at will, and the component layout type may also be more complicated.

[0049] Additionally, in the following description, specific details are provided to provide a thorough understanding of the examples, however, one skilled in the art will appreciate that the examples can be practiced without these specific details.

[0050] The following describes the technical solutions provided by various embodiments of the present application in conjunction with the accompanying drawings. Example

[0051] See Figures 1 to 5 The present invention provides a Raman-LIBS-mass spectrometry analysis device, comprising a multiple reflection time-of-flight mass spectrometer 1, a LIBS spectrometer 2, a Raman spectrometer 3 and a common module; The shared module includes a first incident light path system 4, a second incident light path system 5, a high-definition observation system 6, a vacuum sample chamber 7, a vacuum system 8 and a control system.

[0052] Please refer again Figure 1 The multiple reflection time-of-flight mass spectrometer 1 and the LIBS spectrometer 2 share a first incident light path system 4 and a second incident light path system 5 , and the Raman spectrometer 3 uses the first incident light path system 4 as a laser source.

[0053] Please refer again Figure 2 The multiple-reflection time-of-flight mass spectrometer 1 is configured as a three-dimensional femtosecond laser ablation laser resonance ionization multiple-reflection time-of-flight mass spectrometer, including an interface, an ion transmission system, a multiple-reflection time-of-flight mass analyzer 101 and a detector 102. The first incident light path system 4 and the second incident light path system 5 generate an ion source of the three-dimensional femtosecond laser ablation laser resonance ionization multiple-reflection time-of-flight mass spectrometer; The ion transmission system includes an ion funnel 103, a curved quadrupole 104, a notch filter 105, a 90-degree deflection lens 106 and an ion shaping module 107; the curved quadrupole 104 acts as an ion guide while removing neutral particles to purify the ion beam; the notch filter 105 selectively removes target ions with a specific mass-to-charge ratio (m / z) from an ion beam containing multiple ions, and the 90-degree deflection lens 106 uses an electrostatic field to precisely deflect the ion beam by 90 degrees, while achieving energy and directional focusing of the ions in the process, thereby improving the resolution of the instrument.

[0054] The LIBS spectrometer 2 is configured as a femtosecond multi-pulse laser-induced breakdown enhancement spectrometer, including a spectrum collection module, an optical fiber, a spectrometer, and a LIBS spectrometer detector, for collecting and analyzing spectral signals.

[0055] The Raman spectrometer 3 includes a collecting optical fiber, a filter, a grating or an interferometer, and a Raman spectrometer detector, and is used to collect Raman scattering spectrum signals and perform analysis.

[0056] Please refer again Figure 1 The first incident light path system 4 includes a first laser source 401, an optical path shaping component 402 and a three-dimensional scanning focusing device 403, which are arranged in sequence, and are used to generate a femtosecond laser beam and perform three-dimensional ablation on the sample; A femtosecond laser is provided as the first laser source 401 in the first incident optical path system 4, wherein the wavelength of the femtosecond laser is ≤517 nm, the pulse width is <500 fs, and the repetition frequency is ≥500 kHz; the optical path shaping component 402 includes a high-precision attenuator, a beam expander, a beam shaper, and a reflector arranged in sequence, which are used to adjust the laser energy, beam size, and spatial distribution, wherein the high-precision attenuator can adjust the laser power from full power to the milliwatt level; the three-dimensional scanning focusing device 403 integrates X-axis and Y-axis galvanometers and a Z-axis focusing module, and a beam combiner is provided between the X / Y-axis galvanometer and the Z-axis focusing module; the two-axis scanning galvanometer (X-axis galvanometer, Y-axis galvanometer) and the focusing Z-axis in the three-dimensional scanning focusing device 403 can directly adopt a three-axis galvanometer system; an objective lens 404 is provided at the terminal of the first incident optical path system 4 to focus the regulated laser onto the sample surface to generate plasma and a neutral particle cloud.

[0057] Please refer again Figure 1The second incident optical path system 5 includes a second laser source 501, an independent optical path control unit 502, an optical path merging component 503 and a focusing unit 504 arranged in sequence, which is used to merge the tunable laser into a resonant ionization optical path; after the lasers of multiple second laser sources 501 pass through their respective independent optical path control units 502, they are merged into a second single optical path through the optical path merging component 503, and the second single optical path enters the vacuum sample chamber 7 through the focusing unit 504.

[0058] Please refer again Figure 1 The three second laser sources 501 are configured as tunable lasers with a wavelength tuning range of 210 nm to 4500 nm. Three independent optical path control units 502 are respectively arranged on the optical paths of the three second laser sources 501, including attenuators and beam expanders arranged in sequence. An optical path merging component 503 includes a reflector and a beam combiner to merge multiple laser beams into a single optical path. A focusing unit 504 includes a window and a focusing lens to focus the combined laser beam onto the sample ablation area. According to the target element to be measured, the triggering of the three second laser sources 501 and the wavelength of their respective output lasers are controlled by the control system.

[0059] The coordinated control of the first incident optical path system 4 and the second incident optical path system 5 satisfies the following requirements: the delay time between the femtosecond ablation laser and the resonant ionization laser is less than 1 μs; the synchronization accuracy between the multiple resonant ionization lasers reaches the nanosecond level, and is controlled in real time by the control system. Specifically, the computer sends instructions to the signal control board, the signal control board sends signals to each laser, and the laser emits the required laser according to the signal.

[0060] Please refer again Figure 1 The high-definition observation system 6 is a coaxial observation system, which is mainly composed of a camera, a lens barrel, a beam combiner and an objective lens, wherein the objective lens is shared with the first incident light path system 4, that is, the objective lens 404. The high-definition observation system 6 is used to observe the sample position, sample status and the conditions in the vacuum pool when analyzing the sample.

[0061] Please refer again Figure 1 The vacuum sample chamber 7 includes a three-axis nano-moving stage, a sample holder, and a temperature control stage. The vacuum sample chamber 7 is a fully sealed design; the three-axis nano-moving stage is installed on the base of the vacuum sample chamber 7. It is a three-axis nano-vacuum moving stage with a resolution of less than or equal to 10nm and a repeatability accuracy of less than or equal to 300nm; the temperature control stage is used to accurately control the temperature of the sample with a temperature control accuracy of 0.1 degrees Celsius; the sample holder is used to place and fix the sample.

[0062] The control system is mainly composed of a computing workstation, communication modules for various components, various sensors, vacuum gauges, signal control panels, etc., which collect and process information data and issue control instructions to control the coordinated work of various components.

[0063] Please refer again Figure 1 , the vacuum system 8 includes a mechanical vacuum pump 801 and a turbomolecular pump 802, and the vacuum system 8 is a four-stage gradient vacuum; The first stage of vacuum system 8 is the vacuum pool, interface and ion funnel 103. A large amount of extracted gas is discharged at this stage by mechanical vacuum pump 801. The vacuum degree is required to be less than 300Pa. The second stage vacuum chamber equipped with ion lens has a vacuum degree of less than 0.5Pa. The third stage is the ion guide and notch filter 105 module. The vacuum degree is less than 3*10 -3 Pa; the fourth stage is the multiple reflection time-of-flight mass analyzer 101 and detector 102 modules, which require a vacuum degree of <2*10 -4 The second to fourth vacuum levels are achieved by mechanical vacuum pump 801 and turbomolecular pump 802. That is, after mechanical vacuum pump 801 pre-evacuates, turbomolecular pump 802 is continuously operated to maintain vacuum.

[0064] The multiple-reflection time-of-flight mass spectrometer 1, the LIBS spectrometer 2, and the Raman spectrometer 3 can work independently or simultaneously. When working simultaneously, that is, the three-dimensional femtosecond laser ablation laser resonance ionization multiple-reflection time-of-flight mass spectrometer can simultaneously collect LIBS spectral signals while performing mass spectrometry analysis, thereby realizing complementary analysis of elemental composition under strong matrix interference.

[0065] Please refer again Figure 1 The present invention also provides a Raman-LIBS-mass spectrometry analysis method, which is performed by the Raman-LIBS-mass spectrometry analysis device as described above, comprising the following steps: S1: The system switches to Raman mode. The first incident light path system 4 emits laser light to illuminate the sample to be tested. The Raman spectrometer 3 performs molecular structure imaging to generate multi-dimensional analysis data. S2: The system in the same area switches to mass spectrometer mode, and three-dimensional micro-area femtosecond laser ablation is performed through the first incident light path system 4; S3: Synchronously triggering the tunable laser of the second incident light path system 5 to selectively ionize the target element / isotope; S4: The elemental / isotopic composition is analyzed by multiple reflection time-of-flight mass spectrometer 1, and the elemental distribution is verified by LIBS spectrometer 2.

[0066] U-Pb dating analysis of a zircon sample (TEMORA-1). The first incident beam system, 4, ablated the sample using a femtosecond laser (pulse width 250 fs, spot size 2 μm). The second incident beam system, 5, employed three tunable lasers (λ1 = 283.3 nm, λ2 = 600.2 nm, and λ3 = 1064 nm) to ionize lead atoms in a stepwise fashion. Notch filter 105 was set to m / z = 207.2 ± 0.3 Th, filtering out 207.2 Th. 07Pb⁺ interference. Measured² 06 Pb / ²³ 8 U=0.067±0.003 (2σ), which is better than single laser ablation ICP-MS (±0.02 vs ±0.05).

[0067] The same or similar parts between the various embodiments in this specification can be referred to each other, and each embodiment focuses on the differences from other embodiments.

[0068] The above description is merely a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in the present application should be included in the scope of protection of the present application. Therefore, the scope of protection of the present application should be based on the scope of protection of the claims.

Claims

1. A Raman-LIBS-mass spectrometry analysis device, characterized in that: It includes a multiple reflection time-of-flight mass spectrometer (1), a LIBS spectrometer (2), a Raman spectrometer (3) and a common module; The shared module includes a first incident light path system (4), a second incident light path system (5), a high-definition observation system (6), a vacuum sample chamber (7), a vacuum system (8), and a control system; The first incident light path system (4) comprises a first laser source (401), a light path shaping component (402), and a three-dimensional scanning focusing device (403) arranged in sequence, and is used to generate a femtosecond laser beam and perform three-dimensional ablation on the sample; The second incident light path system (5) comprises a second laser source (501), an independent light path control unit (502), a light path merging component (503) and a focusing unit (504) arranged in sequence, and is used to merge the tunable laser into a resonant ionization light path; The multiple reflection time-of-flight mass spectrometer (1) and the LIBS spectrometer (2) share a first incident light path system (4) and a second incident light path system (5), and the Raman spectrometer (3) uses the first incident light path system (4) as a laser source.

2. The Raman-LIBS-mass spectrometry analysis device according to claim 1, characterized in that: The second incident light path system (5) is provided with a plurality of second laser sources (501), and the second laser sources (501) are configured as tunable lasers, and the wavelength tuning range of the tunable lasers is 210 nm to 4500 nm; The independent optical path control unit (502) corresponds one-to-one to the second laser source (501), and includes an attenuator and a beam expander arranged in sequence; The optical path merging component (503) comprises a reflector and a beam combining mirror, and is used to merge multiple laser beams into a single optical path; The focusing unit (504) includes a window and a focusing lens, and focuses the combined laser light onto the sample ablation area; After the lasers from the plurality of second laser sources (501) pass through the independent light path control unit (502), they are merged into a second single light path via the light path merging component (503), and the second single light path enters the vacuum sample chamber (7) via the focusing unit (504).

3. The Raman-LIBS-mass spectrometry analysis device according to claim 2, characterized in that: The working quantity of the second laser source (501) can be dynamically adjusted by a control system and selectively combined and triggered according to the ionization requirements of the target element.

4. The Raman-LIBS-mass spectrometry analysis device according to claim 2, characterized in that: The multiple reflection time-of-flight mass spectrometer (1) is configured as a three-dimensional femtosecond laser ablation laser resonance ionization multiple reflection time-of-flight mass spectrometer (1), comprising an interface, an ion transmission system, a multiple reflection time-of-flight mass analyzer (101) and a detector (102), wherein the first incident light path system (4) and the second incident light path system (5) generate an ion source of the three-dimensional femtosecond laser ablation laser resonance ionization multiple reflection time-of-flight mass spectrometer (1); The ion transmission system comprises an ion funnel (103), a bent quadrupole (104), a notch filter (105), a 90-degree deflection lens (106), and an ion shaping module (107).

5. The Raman-LIBS-mass spectrometry analysis device according to claim 2, characterized in that: A femtosecond laser is provided as a first laser source (401) in the first incident light path system (4), wherein the wavelength of the femtosecond laser is ≤517 nm, the pulse width is <500 fs, and the repetition frequency is ≥500 kHz; The optical path shaping component (402) comprises a high-precision attenuator, a beam expander, a beam shaper and a reflector arranged in sequence, and is used to adjust the laser energy, beam size and spatial distribution; The three-dimensional scanning and focusing device (403) integrates X-axis and Y-axis galvanometers and a Z-axis focusing module, and a beam combining mirror is provided between the X-axis and Y-axis galvanometers and the Z-axis focusing module; An objective lens (404) is provided at the terminal of the first incident light path system (4) to focus the regulated laser light onto the sample surface, thereby generating plasma and a neutral particle cloud.

6. The Raman-LIBS-mass spectrometry analysis device according to claim 5, characterized in that: The coordinated control of the first incident light path system (4) and the second incident light path system (5) satisfies the following conditions: the delay time between the femtosecond ablation laser and the resonant ionization laser is less than 1 μs; the synchronization accuracy between the multiple resonant ionization laser beams reaches the nanosecond level and is controlled in real time by the control system.

7. The Raman-LIBS-mass spectrometry analysis device according to claim 2, characterized in that: The vacuum system (8) includes a mechanical vacuum pump (801) and a turbomolecular pump (802); The vacuum system (8) is a four-stage gradient vacuum system, wherein the first stage vacuum degree is <300 Pa, which is achieved by a mechanical vacuum pump (801), the second stage vacuum degree is <0.5 Pa, and the third stage vacuum degree is <3*10 -3 Pa, fourth level vacuum degree <2*10 -4 Pa; the second to fourth stages of vacuum are achieved by using a mechanical vacuum pump (801) and a turbomolecular pump (802).

8. The Raman-LIBS-mass spectrometry analysis device according to claim 4, characterized in that: The multiple reflection time-of-flight mass spectrometer (1), the LIBS spectrometer (2), and the Raman spectrometer (3) can work independently or simultaneously.

9. The Raman-LIBS-mass spectrometry analysis device according to claim 8, characterized in that: The LIBS spectrometer (2) is configured as a femtosecond multi-pulse laser-induced breakdown enhancement spectrometer. The LIBS spectrometer (2) works synchronously with the multiple reflection time-of-flight mass spectrometer (1) during analysis. That is, the three-dimensional femtosecond laser ablation laser resonance ionization multiple reflection time-of-flight mass spectrometer can simultaneously collect LIBS spectrum signals when performing mass spectrometry analysis, thereby realizing complementary analysis of elemental composition under strong matrix interference.

10. A Raman-LIBS-mass spectrometry analysis method, performed by using the Raman-LIBS-mass spectrometry analysis device according to claim 1, characterized in that: The steps include: S1: The system switches to Raman mode, the first incident light path system (4) emits laser light to illuminate the sample to be tested, and the Raman spectrometer (3) performs molecular structure imaging to form multi-dimensional analysis data; S2: The system in the same area is switched to mass spectrometer mode, and three-dimensional micro-area femtosecond laser ablation is performed through the first incident light path system (4); S3: Synchronously triggering the tunable laser of the second incident light path system (5) to selectively ionize the target element / isotope; S4: Elemental / isotopic composition was analyzed by multiple reflection time-of-flight mass spectrometry (1), and elemental distribution was verified by combined LIBS spectrometer (2).

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