Electrochemical flow cell device and method for near-normal-pressure X-ray photoelectron spectroscopy in-situ test

Abstract

The invention provides an electrochemical flow cell device for near-normal-pressure X-ray photoelectron spectroscopy in-situ testing, and relates to the field of near-normal-pressure X-ray photoelectron spectroscopy experimental instruments. The electrochemical flow cell device for the near-normal-pressure X-ray photoelectron spectroscopy in-situ test comprises a fixing mechanism and an electrochemical in-situ cell arranged on the fixing mechanism, and the electrochemical in-situ cell is located in an APXPS cavity; the electrochemical in-situ pool sequentially comprises a front plate, a gold net, an ion exchange membrane, an insulating plate, a back plate and two gas-liquid sample introduction pipes which are detachably connected, and the back plate is detachably connected with the fixing mechanism; the ion exchange membrane is coated with a sample, a light inlet through hole is formed in the front plate, a gas-liquid channel is formed in the back plate, and the two gas-liquid sample injection pipes penetrate through the fixing mechanism to be connected with the back plate and are communicated with an inlet and an outlet of the gas-liquid channel respectively. According to the invention, the real-time observation of the electrode surface species and the catalyst valence state is realized under the near-normal-pressure condition.

Description

Technical Field

[0001] The invention relates to the field of near-ambient-pressure X-ray photoelectron spectroscopy experimental instruments, in particular to an electrochemical flow cell device for near-ambient-pressure X-ray photoelectron spectroscopy in-situ testing and its application. Background Art

[0002] When X-rays interact with matter, electrons and photons are excited. By measuring the energy and direction of these photoelectrons, we can obtain electronic structure information with element resolution in different chemical environments, especially detailed information on occupied states and core energy levels, which constitutes the basic principle of photoelectron spectroscopy.

[0003] However, due to the limited penetration ability caused by the strong interaction between X-ray excited photoelectrons and matter, photoelectron spectroscopy is highly sensitive to the surface. Especially in photoelectron spectroscopy using soft X-rays, the detection depth is usually only at the nanometer level. This surface sensitivity has obvious advantages in studying catalyst surface reactions. Traditional photoelectron spectroscopy technology has been widely used in surface science research under ultra-high vacuum (UHV) conditions. Under UHV environment, researchers can obtain highly pure and stable atomic-level surfaces, and then directly detect the composition, valence state and electronic structure of single crystal model catalysts, so as to infer the competitive adsorption, dissociation and desorption process of molecules on the catalyst surface. This provides an important theoretical basis for understanding the mechanism of catalytic reactions. However, there is a significant "pressure gap" between the research under UHV conditions and the actual catalytic reaction environment. This gap may cause changes in the surface structure of the material, making the research results obtained under vacuum environment unable to fully reflect the surface state of the catalyst under actual reaction conditions. In order to solve this problem, near-atmospheric pressure X-ray photoelectron spectroscopy (APXPS) technology came into being and has developed rapidly in recent years. APXPS evolved on the basis of traditional X-ray photoelectron spectroscopy (XPS). Due to the strong interaction between photoelectrons and matter, the inelastic collision mean free path (IMFP) of photoelectrons will be significantly shortened with the increase of gas pressure (for example, the IMFP of photoelectrons with a kinetic energy of 500eV in 1mbar O2 is only about 2mm). In order to effectively analyze the gas / solid and liquid / solid interfaces, it is necessary to shorten the flight path of photoelectrons in the gas as much as possible so that they can quickly enter the analyzer in ultra-high vacuum. In the 1960s and 1970s, Professor Siegbahn introduced the vacuum differential technology and applied XPS to the study of free gas molecules and liquids, thus laying the foundation for APXPS technology. In addition, the design and development of in-situ cells enable researchers to perform XPS tests at near-normal pressure or even higher pressure conditions, and directly observe the dynamic changes of materials under working conditions.

[0004] This is of great significance for a deeper understanding of the mechanism of catalytic reactions and the regulation of material properties. In particular, the development and application of the XPS electrochemical in-situ cell is of revolutionary significance in the field of electrochemistry, providing a powerful tool for studying interfacial phenomena during electrochemical reactions. Traditional electrochemical research methods, such as cyclic voltammetry and electrochemical impedance spectroscopy, can provide indirect information on the kinetics and mechanism of electrochemical reactions, but they lack the ability to directly detect changes in the electronic structure and chemical environment during the reaction.

[0005] The XPS electrochemical in-situ cell combines the element resolution and surface sensitivity of XPS, allowing researchers to observe the chemical changes and electronic structure evolution occurring on the electrode surface in real time during the electrochemical reaction. However, the development and application of the XPS electrochemical in-situ cell also faces a series of technical challenges.

[0006] First, 1) the liquid electrolyte in the electrochemical environment will significantly absorb or scatter X-rays, which increases the difficulty of photoelectron detection. Secondly, 2) maintaining the stability and operability of the electrode under in situ conditions while ensuring the high quality of the XPS signal requires precise cell design and strict control of experimental conditions. In addition, 3) the XPS electrochemical in situ cell must overcome the limitations of material selection to ensure that the cell material remains stable in high voltage, high temperature or corrosive environments.

[0007] It is worth mentioning that despite these challenges, the development of XPS electrochemical in-situ cells is continuously expanding its application areas, enabling scientists to obtain more in-depth information on material surfaces and interfaces under real electrochemical conditions. This not only promotes the development of basic scientific research, but also provides key experimental basis for the design and optimization of new electrochemical devices. As the technology matures further, XPS electrochemical in-situ cells will play an increasingly important role in energy storage, catalysis, electrolysis, and water treatment. Summary of the invention

[0008] In order to solve the above problems, the first aspect of the present invention provides an electrochemical flow cell device for in-situ testing of near-ambient pressure X-ray photoelectron spectroscopy, which can directly observe key intermediates in oxygen reduction reactions at different electrochemical potentials.

[0009] The present invention provides an electrochemical flow cell device for near-atmospheric pressure X-ray photoelectron spectroscopy in-situ testing, comprising a fixing mechanism and an electrochemical in-situ cell arranged on the fixing mechanism, wherein the electrochemical in-situ cell is located in an APXPS cavity; the electrochemical in-situ cell comprises, in sequence, a detachably connected front plate, a gold mesh, an ion exchange membrane, an insulating plate, a back plate and two gas-liquid injection tubes, wherein the back plate is detachably connected to the fixing mechanism; a sample is coated on the ion exchange membrane, a light inlet hole is provided in the front plate, a gas-liquid passage is provided on the back plate, the two gas-liquid injection tubes are both connected to the back plate through the fixing mechanism, and the two gas-liquid injection tubes are respectively connected to the inlet and outlet of the gas-liquid passage.

[0010] In a feasible embodiment, the fixing mechanism includes a sample rod and a fixing bracket arranged at the bottom of the sample rod, and the fixing bracket is detachably connected to the back plate; electrode leads are provided in the sample rod, and the electrode leads are respectively connected to the back plate and the front plate.

[0011] In a feasible implementation, the light-inlet through hole includes a straight slot channel and an oblique slot channel that are interconnected, and the diameter of the oblique slot channel gradually decreases in a direction approaching the straight slot channel; the gold mesh abuts against an outlet of the straight slot channel.

[0012] In a feasible implementation manner, the radius of the straight groove channel is 5 to 7 mm; and / or the inclination angle of the side wall of the inclined groove channel is 10 to 20°.

[0013] In a feasible implementation manner, the gas-liquid passage includes a plurality of parallel straight sections, and a bending section is provided between each adjacent straight section.

[0014] In a feasible implementation manner, an annular groove is provided on the surface of the back plate that abuts against the ion exchange membrane, and a sealing ring is provided in the annular groove.

[0015] In a feasible embodiment, the gas-liquid sample rod is sealedly connected to the gas-liquid through-hole bracket via an inverted cone joint; and / or, a valve body is provided on the gas-liquid sample rod; and / or, the diameter of the gas-liquid sample rod is 1 to 2 mm; and / or, the wire diameter of the gold mesh is 5 to 15 μm.

[0016] In a feasible implementation manner, the front plate and the insulating plate are provided with a plurality of first screw holes, and the surface of the back plate abutting against the ion exchange membrane is also provided with a plurality of first screw holes; the corresponding first screw holes are connected by first fixing screws.

[0017] In a feasible implementation manner, the fixing bracket is provided with a plurality of second screw holes, and the surface of the back plate connected to the fixing bracket is also provided with a plurality of second screw holes; the corresponding second screw holes are connected by second fixing screws.

[0018] The second aspect of the present invention provides a method for using the electrochemical flow cell device according to the first aspect of the present invention, comprising at least the following steps:

[0019] 1) Coating a sample on an ion exchange membrane;

[0020] 2) assembling an electrochemical in-situ cell;

[0021] 3) Fill the APXPS chamber with reaction gas, and fill the gas-liquid inlet tube with humidified reaction gas or solution;

[0022] 4) X-rays are irradiated to the sample on the ion exchange membrane at grazing incidence

[0023] The present invention provides an electrochemical flow cell device and method for in-situ testing of near-normal pressure X-ray photoelectron spectroscopy, which has the following beneficial effects:

[0024] 1) The present invention realizes real-time observation of electrode surface species and catalyst valence states under near-normal pressure conditions, which is difficult to achieve under traditional ultra-high vacuum conditions. It enables researchers to directly observe key intermediates in oxygen reduction reactions under different electrochemical potentials and provides a scientific basis for optimizing fuel cell and electrolyzer catalysts.

[0025] 2) Furthermore, the gas-liquid passage of the present invention includes five straight sections and four bent sections, so that the entire gas-liquid through hole presents a serpentine flow channel, which helps the electrode reactants to fully contact the electrode catalysts, and the single flow channel also helps to minimize the dead volume of the flow channel. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a schematic diagram of the overall structure explosion of the present invention.

[0027] Figure 2 It is a schematic structural diagram of the front plate in the present invention.

[0028] Figure 3 It is a cross-sectional schematic diagram of the front plate in the present invention.

[0029] Figure 4 It is a schematic diagram of the structure of the back plate and the gas-liquid passage in the present invention.

[0030] Figure 5 It is a schematic diagram of the structure of the backplane in the present invention.

[0031] Figure 6 It is a schematic diagram of the overall structure of the present invention.

[0032] Figure 7 It is a structural schematic diagram of the fixing mechanism in the present invention.

[0033] Figure 8This is a schematic diagram of the present invention.

[0034] Reference numerals

[0035] Fixed mechanism 1

[0036] Sample holder 11

[0037] Fixed bracket 12

[0038] Electrochemical in situ cell 2

[0039] Front panel 3

[0040] Working electrode hole 31

[0041] Light through hole 32

[0042] Straight channel 32.1

[0043] Chute channel 32.2

[0044] Gold Net 4

[0045] Ion exchange membrane 5

[0046] Insulation board 6

[0047] Back Panel 7

[0048] Counter electrode hole 71

[0049] Gas-liquid passage 72

[0050] Direct section 72.1

[0051] Bend section 72.2

[0052] Annular groove 72.3

[0053] Gas and liquid injection tube 8

[0054] Sealing ring 9 DETAILED DESCRIPTION

[0055] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in the field without creative work belong to the scope of protection of the present invention. In the description of the present invention, it should be noted that the orientation or position relationship indicated by the terms "left side", "right side", "upper side", "lower side", "above", "below" and the like is based on the orientation or position relationship shown in the drawings, which is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0056] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0057] Furthermore, in the description of the present invention, unless otherwise specified, “plurality” means two or more.

[0058] The present invention provides an electrochemical flow cell device for near-ambient pressure X-ray photoelectron spectroscopy in-situ testing. Figures 1 to 4 , comprising a fixing mechanism 1 and an electrochemical in-situ cell 2 arranged on the fixing mechanism 1, wherein the electrochemical in-situ cell 2 is located in the APXPS cavity; the electrochemical in-situ cell 2 comprises a detachably connected front plate 3, a gold mesh 4, an ion exchange membrane 5, an insulating plate 6, a back plate 7 and two gas-liquid injection tubes 8 in sequence, wherein the back plate 7 is detachably connected to the fixing mechanism 1; the ion exchange membrane 5 is coated with a sample, a light inlet hole 32 is provided in the front plate 3, a gas-liquid passage 72 is provided on the back plate 7, the two gas-liquid injection tubes 8 are both connected to the back plate 7 through the fixing mechanism 1, and the two gas-liquid injection tubes 8 are respectively connected to the inlet and outlet of the gas-liquid passage 72.

[0059] About ion exchange membrane 5: Figure 1The sample is usually evenly mixed with the discrete polymer into a slurry and sprayed on the ion exchange membrane 5. During the experiment, the back plate 7 and the front plate 3 are respectively connected to the working electrodes; at the same time, it is stipulated that the direction in which the ion exchange membrane 5 and the gold mesh 4 are against each other is the working electrode side, and the direction in which the ion exchange membrane 5 and the back plate 7 are against each other is the counter electrode side.

[0060] About Jinwang4: Figure 1 and Figure 6 , because the light-intake through hole 32 in the front plate 3 causes the ion exchange membrane 5 to be exposed to the environment, which may cause charging, and the gold mesh 4 can make the electric field distribution on the surface of the sample to be tested relatively uniform without affecting the XPS signal, thereby preventing charging during the test. In a specific embodiment, the wire diameter of the gold mesh 4 is 5 to 15 μm, preferably 10 μm.

[0061] About gas and liquid injection tube 8: see Figure 1 and Figure 6 Generally speaking, an ultra-vacuum flange is also provided in the fixing mechanism 1, and a feed-through is preset on the ultra-vacuum flange. One end of the gas-liquid sampling tube 8 is connected to a gas flow meter (for gas sampling) or a micro-injection pump (for liquid sampling), and the other end is connected to the back plate 7 through an insulating material inverted cone joint. When the two gas-liquid sampling tubes 8 are in use, they form a cycle with the gas-liquid passage 72, one gas-liquid sampling tube 8 is responsible for sampling, and the other gas-liquid sampling tube 8 is responsible for sampling, so that the gas and liquid can circulate in the gas-liquid passage 72. In a specific embodiment, a valve body is provided on the gas-liquid sample rod 11. In another specific embodiment, the diameter of the gas-liquid sample rod 11 is 1 to 2 mm, preferably 1.6 mm.

[0062] For front panel 3 and back panel 7: Figure 1 , Figure 5 and Figure 6 , because the front plate 3 and the back plate 7 are used as the working electrode side and the counter electrode side respectively, the front plate 3 and the back plate 7 are made of corrosion-resistant and electrochemically inert materials, preferably titanium alloy materials. As an explanation, generally speaking, the front plate 3 and the back plate 7 are energized during the experiment, so in order to prevent the front plate 3 and the back plate 7 from contacting and short-circuiting, an insulating plate 6 is provided between the front plate 3 and the back plate 7. The outer diameters of the front plate 3, the back plate 7 and the insulating plate 6 are usually the same, so that it can be ensured that the front plate 3 and the back plate 7 cannot contact each other, thereby ensuring the safety of the experiment.

[0063] The electrochemical flow cell device provided in the embodiment of the present invention is shown in FIG. Figure 1 and Figure 7The fixing mechanism 1 includes a sample rod 11 and a fixing bracket 12 arranged at the bottom of the sample rod 11, and the fixing bracket 12 is detachably connected to the back plate 7. The sample rod 11 is provided with electrode leads, and the electrode leads are respectively connected to the back plate 7 and the front plate 3. Generally speaking, the front plate 3 is connected to the working electrode required for XPS testing, and the back plate 7 is connected to the counter electrode that meets the electrochemical requirements and does not need to be measured. Figure 2 and Figure 5 In one specific embodiment, the front plate 3 is provided with a working electrode hole 31, and the back plate 7 is provided with a counter electrode hole 71; the electrode leads include a working electrode lead and a counter electrode lead, the working electrode lead passes through the working electrode hole 31 to be connected to the front plate 3, and the counter electrode lead passes through the counter electrode hole 71 to be connected to the back plate 7. In another specific embodiment, the sample rod 11 uses a commercial CF16 ultra-high vacuum flange to BNC connector, the ultra-vacuum flange is located on the APXPS chamber, the BNC connector is located on the top of the sample rod 11 and is located outside the APXPS chamber, the working electrode lead and the counter electrode lead both use vacuum Kapton cables, the working electrode lead and the counter electrode lead located inside the APXPS chamber are inserted into the working electrode hole 31 and the counter electrode hole 71 with M1.2 corrosion-resistant Ti screws after passing through the working electrode hole 31 and the counter electrode hole 71 respectively, and the working electrode and the counter electrode are connected to the electrochemical workstation outside the APXPS chamber through a BNC connector to alligator clip connection cable. In a specific embodiment, four CF16 flange electrodes are reserved in the sample rod 11 .

[0064] The electrochemical flow cell device provided in the embodiment of the present invention is shown in FIG. Figure 2 and Figure 3 , the light inlet hole 32 includes a straight slot channel 32.1 and an oblique slot channel 32.2 that are interconnected, and the diameter of the oblique slot channel 32.2 gradually decreases in the direction close to the straight slot channel 32.1; the gold mesh 4 is against the outlet of the straight slot channel 32.1. In a specific embodiment, the inclination angle of the side wall of the oblique slot channel 32.2 is 10 to 20°, preferably 15°. As an illustration, most XPS systems use a grazing incidence X-ray method, so the inclination angle of the side wall of the oblique slot channel 32.2 can meet the requirements of the XPS system. In another specific embodiment, the radius of the straight slot channel 32.1 is 5 to 7 mm, preferably 6 mm.

[0065] The electrochemical flow cell device provided in the embodiment of the present invention is shown in FIG. Figure 4 and Figure 5 The gas-liquid passage 72 includes a plurality of parallel straight sections 72.1, and a bending section 72.2 is provided between each adjacent straight section 72.1. Figure 4The gas-liquid passage 72 includes five straight sections 72.1 and four bent sections 72.2, so that the entire gas-liquid through hole presents a serpentine flow channel. This method helps the electrode reactants to fully contact the electrode catalysts, and the single flow channel also helps to minimize the dead volume of the flow channel.

[0066] The electrochemical flow cell device provided in the embodiment of the present invention is shown in FIG. Figure 1 and Figure 4 The surface of the back plate 7 that abuts against the ion exchange membrane 5 is provided with an annular groove 72.3, and a sealing ring 9 is provided in the annular groove 72.3. As an illustration, the sealing ring 9 can improve the sealing effect between the back plate 7 and the ion exchange membrane 5.

[0067] The electrochemical flow cell device provided in the embodiment of the present invention is shown in FIG. Figure 1 , the front plate 3 and the insulating plate 6 are provided with a plurality of first screw holes, the surface of the back plate 7 against the ion exchange membrane 5 is also provided with a plurality of first screw holes, and the corresponding first screw holes are connected by a first fixing screw. As an illustration, the first fixing screw is preferably an insulating material screw. After the assembly is completed in the above manner, the first fixing screw tightens the front plate 3, the ion exchange membrane 5 of the sprayed sample, and the back plate 7 in sequence, so that the atmospheric pressure level gas / liquid on the electrode side of the ion exchange membrane 5 is sealed in the flow channel, and the vacuum degree of the APXPS test environment is controlled at the level of hectopascals. In a specific embodiment, the number of the first screw holes on the front plate 3, the insulating plate 6 and the back plate 7 is 4. In another specific embodiment, the fixing bracket 12 is provided with a plurality of second screw holes, and the surface of the back plate 7 connected to the fixing bracket 12 is also provided with a plurality of second screw holes; the corresponding second screw holes are connected by a second fixing screw. As an illustration, the second fixing screw is preferably an insulating material screw. In a specific embodiment, the number of the second screw holes on the back plate 7 and the fixing bracket 12 is 4.

[0068] The present invention also provides a method for using an electrochemical flow cell device for near-ambient pressure X-ray photoelectron spectroscopy in-situ testing, which includes at least the following steps. Figure 1 , 8 :

[0069] 1) Coating a sample on an ion exchange membrane 5; for illustration, the ion exchange membrane 5 generally uses a molecular polymer membrane as a proton or ion conductor, and nano-scale catalyst particles are coated on both sides, serving as a working electrode and a counter electrode, respectively.

[0070] 2) Assembling the electrochemical in-situ cell 2; assembling the fixing bracket 12, the back plate 7, the sealing ring 9, the isolation plate, the ion exchange membrane 5, the gold mesh 4 and the front plate 3 together by means of the first fixing screw and the second screw.

[0071] 3) Fill the APXPS chamber with reactive gas and the gas-liquid inlet tube 8 with humidified reactive gas or solution

[0072] 4) X-rays are irradiated to the sample on the ion exchange membrane 5 at grazing incidence. Under different reaction gas pressure and potential conditions, the XPS spectrum of the sample on the ion exchange membrane 5 is collected to study how important information such as each adsorbed species and catalyst valence state changes with potential.

[0073] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and substitutions can be made without departing from the technical principles of the present invention. These improvements and substitutions should also be regarded as the scope of protection of the present invention.

Claims

1. An electrochemical flow cell device for near-ambient pressure X-ray photoelectron spectroscopy in-situ testing, characterized in that: It comprises a fixing mechanism (1) and an electrochemical in-situ cell (2) arranged on the fixing mechanism (1), wherein the electrochemical in-situ cell (2) is located in an APXPS cavity; The electrochemical in-situ cell (2) comprises, in sequence, a detachably connected front plate (3), a gold mesh (4), an ion exchange membrane (5), an insulating plate (6), a back plate (7) and two gas-liquid injection tubes (8), wherein the back plate (7) is detachably connected to the fixing mechanism (1); The ion exchange membrane (5) is coated with a sample, the front plate (3) is provided with a light inlet hole (32), the back plate (7) is provided with a gas-liquid passage (72), the two gas-liquid injection tubes (8) are connected to the back plate (7) through the fixing mechanism (1), and the two gas-liquid injection tubes (8) are respectively connected to the inlet and outlet of the gas-liquid passage (72).

2. The electrochemical flow cell device according to claim 1, characterized in that: The fixing mechanism (1) comprises a sample rod (11) and a fixing bracket (12) arranged at the bottom of the sample rod (11), wherein the fixing bracket (12) is detachably connected to a back plate (7); an electrode lead is arranged on the sample rod (11), and the electrode lead is respectively connected to the back plate (7) and the front plate (3).

3. The electrochemical flow cell device according to claim 2, characterized in that: The front plate (3) is provided with a working electrode hole (31), and the back plate (7) is provided with a counter electrode hole (71); the electrode leads include a working electrode lead and a counter electrode lead, the working electrode lead passes through the working electrode hole (31) to be connected to the front plate (3), and the counter electrode lead passes through the counter electrode hole (71) to be connected to the back plate (7).

4. The electrochemical flow cell device according to claim 1, characterized in that: The light-inlet through hole (32) comprises a straight groove channel (32.1) and an oblique groove channel (32.2) that are interconnected, and the diameter of the oblique groove channel (32.2) gradually decreases in a direction approaching the straight groove channel (32.1); the gold net (4) abuts against the outlet of the straight groove channel (32.1).

5. The electrochemical flow cell device according to claim 4, characterized in that: The radius of the straight groove channel (32.1) is 5 to 7 mm; and / or the inclination angle of the side wall of the oblique groove channel (32.2) is 10 to 20°.

6. The electrochemical flow cell device according to claim 1, characterized in that: The gas-liquid passage (72) comprises a plurality of parallel straight sections (72.1), and a bending section (72.2) is provided between adjacent straight sections (72.1).

7. The electrochemical flow cell device according to claim 1, characterized in that: An annular groove (72.3) is provided on the surface of the back plate (7) that abuts against the ion exchange membrane (5), and a sealing ring (9) is provided in the annular groove (72.3).

8. The electrochemical flow cell device according to claim 1, characterized in that: The gas-liquid inlet tube (8) is sealedly connected to the back plate (7) via an inverted cone joint; and / or, a valve body is provided on the gas-liquid sample rod (11); and / or, the diameter of the gas-liquid sample rod (11) is 1 to 2 mm; and / or, the wire diameter of the gold mesh (4) is 5 to 15 μm.

9. The electrochemical flow cell device according to claim 1, characterized in that: The front plate (3) and the insulating plate (6) are provided with a plurality of first screw holes, and the surface of the back plate (7) abutting against the ion exchange membrane (5) is also provided with a plurality of first screw holes; the corresponding first screw holes are connected by first fixing screws; and / or, the fixing bracket (12) is provided with a plurality of second screw holes, and the surface of the back plate (7) connecting to the fixing bracket (12) is also provided with a plurality of second screw holes; the corresponding second screw holes are connected by second fixing screws.

10. A method for using the electrochemical flow cell device according to any one of claims 1 to 9, comprising at least the following steps: 1) coating a sample on an ion exchange membrane (5); 2) assembling an electrochemical in-situ cell (2); 3) The APXPS chamber is charged with reaction gas, and the gas-liquid inlet tube (8) is charged with humidified reaction gas or solution; 4) X-rays are irradiated onto the sample on the ion exchange membrane (5) at grazing incidence.

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