CN118258870A - Sampling probe electrode and in-situ electrochemical microsampling detection system - Google Patents

Abstract

The invention discloses a sampling probe electrode and an in-situ electrochemical microsampling detection system, the sampling probe electrode comprises a sampling probe electrode body with a tip and a hollow channel, a plurality of mutually insulated metal electrode layers are coated outside the tip, a filling material which is selectively penetrated by gas is filled in the hollow channel, and the filling material comprises a polymer film and/or a metal-organic framework MOF material. The filling material for selectively penetrating the gas is filled in the sampling probe electrode, and the metal electrode layer is coated outside the tip of the probe, so that the adaptability can be improved, the gas sampling detection of multiple systems can be met, the gas can be selectively penetrated, and the detection requirement can be met; the in-situ electrochemical micro-sampling detection system comprises a vacuum electrode sampling module and a trace gas analysis module; the vacuum electrode sampling module comprises the sampling probe electrode; the system can be used for in-situ real-time product detection of various electrochemical catalytic systems, realizes coupling of electrochemical signals with product types and yields, has good stability of the whole system, is simple and convenient to operate, and can obtain stable and accurate test results on the premise of not affecting the performance of the electrochemical catalyst.

Description

A sampling probe electrode and an in-situ electrochemical micro-sampling detection system

Technical Field

The invention relates to a sampling probe electrode and an in-situ electrochemical micro-sampling detection system, belonging to the technical field of electrochemical analysis.

Background technique

Electrochemical catalysis is a scientific field that studies how to use catalysts to promote related reactions in electrochemical systems. The research fields involved in electrochemical catalysis are very broad, including energy conversion, environmental governance, industrial production and other fields. For example, in the field of energy conversion, electrochemical catalysis can be used in reactions such as fuel cells and water electrolysis to produce hydrogen to improve reaction efficiency and product purity. In the field of environmental governance, electrochemical catalysis can be used in reactions such as degradation of organic pollutants and removal of heavy metals to achieve environmental purification.

In most existing electrochemical catalytic systems, the knowledge of the generation process of intermediate and final products is extremely limited. In addition, due to the limitation of the reaction mechanism of the system, various gas products are mostly in the pmol level. Conventional characterization methods cannot detect trace gases in the system reaction process in situ and in real time. In addition, the existing sampling electrode probes can detect fewer systems and cannot selectively transport the collected gas to the gas analysis module.

Therefore, it is an urgent problem to be solved by technicians in this field to provide a sampling electrode probe that can detect more systems and transport the gas generated by electrochemical reactions to a gas separation module, as well as an in-situ real-time electrochemical trace product sampling and detection system that is suitable for studying the reaction mechanisms of different catalysts in electrochemical systems and coupling electrochemical signals with electrochemical products.

Summary of the invention

The first purpose of the present invention is to provide a sampling probe electrode that is suitable for selectively permeating gas by filling the inside of the sampling probe electrode with a filling material and coating the outside of the probe tip with a metal electrode layer, thereby improving adaptability and meeting the gas sampling and detection of multiple systems. At the same time, it can also selectively permeate gas to meet detection requirements.

In order to achieve the above object, the technical solution adopted by the present invention is:

A sampling probe electrode comprises a sampling probe electrode body having a tip and a hollow channel, wherein the tip is coated with a plurality of mutually insulated metal electrode layers, and the hollow channel is filled with a filling material for selective gas permeation, wherein the filling material comprises a polymer film and/or a metal organic framework (MOF) material.

Preferably, the sampling probe electrode body is a glass capillary.

Preferably, the tip is any one of carbon nanotubes, conductive rubber, conductive nanometal materials, and non-conductive materials;

Wherein, the conductive nanometal material includes metal nanoparticles or metal nanowires; and the non-conductive material includes glass fibers.

Preferably, the metal electrode layer includes an Au electrode layer and a Pt electrode layer.

An in-situ electrochemical trace sampling detection system includes a main controller, a vacuum electrode sampling module and a trace gas analysis module;

The vacuum electrode sampling module comprises an electrochemical sample stage, a potential controller, a first XYZ coordinate stage, a displacement controller and at least one sampling probe electrode according to any one of claims 1 to 5;

The electrochemical sample stage is used to place the electrochemical test sample, and a reference electrode and an auxiliary electrode are provided at the base;

The potential controller is connected to the metal electrode layer of the sampling probe electrode and the main controller, and is used to control the electrochemical parameters of each electrode in the electrochemical reaction system;

The electrochemical sample stage is arranged on a first XYZ coordinate stage, and the first XYZ coordinate stage is connected to a displacement controller and a main controller, and is used to control the displacement of the electrochemical sample stage in a three-dimensional space to change the position of the sampling probe electrode in the electrochemical field;

The sampling probe electrode is used to apply the electrochemical signal provided by the potential controller to the electrochemical field in the electrochemical sample stage, and can allow the gas generated by the electrochemical reaction to selectively permeate;

The trace gas analysis module is connected to the main controller and the sampling probe electrode, and is used to collect the gas transmitted through the sampling probe electrode and to ionize and detect the transmitted gas.

Preferably, the trace gas analysis module comprises a sampling capillary, a high cyclotron ionization ion source, a vacuum device, a mass analyzer and a detection module;

The injection capillary is connected to the hollow channel of the sampling probe electrode and the high cyclotron ionization ion source, which is in turn connected to the mass analyzer and the detection module, and is also connected to the vacuum device; the detection module is connected to the main controller;

Under the action of the vacuum equipment, the gas that selectively passes through the sampling probe electrode enters the high-cyclotron ionization source through the injection capillary. The gas is ionized by the high-cyclotron ionization source to form a charged ion beam. The charged particle beam enters the mass analyzer and is separated into charged particles of different masses. The detection module detects the current generated by the charged particles of different masses.

Preferably, there are multiple sampling probe electrodes distributed in an array.

Preferably, the vacuum electrode sampling module further comprises a multi-channel array injector;

The multi-channel array injector comprises a sleeve, a rotor arranged in the sleeve, and a stepper motor for driving the rotor to rotate in the sleeve; the sleeve is fixed on the second XYZ coordinate stage, and the second XYZ coordinate stage and the stepper motor are also connected to the displacement controller, and the displacement controller controls the rotation of the execution shaft of the stepper motor and the movement of the second XYZ coordinate stage;

Among them, a plurality of threaded holes connected to the inner cavity of the sleeve are distributed along the thread line on the sleeve, and the sampling probe electrode is connected to the threaded hole by using a connecting capillary; the rotor has an intermediate channel and a microhole connected to the intermediate channel is opened on the peripheral body, and the sampling capillary is connected to the intermediate channel of the rotor;

The stepper motor drives the rotor to make spiral motion in the sleeve, and the second XYZ coordinate table drives the sleeve to move along the Z direction. When the micropores on the rotor correspond to the threaded holes on the sleeve, the gas produced at a certain position in the electrochemical field will be pumped to the high-cyclotron ionization ion source to achieve gas ionization. After the charged particles of different masses are separated by the mass analyzer, the current generated by the charged particles of different masses is detected by the detection module.

Preferably, the charged ions separated in the high cyclotron ionization ion source enter the mass analyzer vertically in a pulsed manner.

Preferably, an electromagnet is provided in the high-cyclotron ionization source, and the electrons emitted from the high-cyclotron ionization source move in a spiral motion under the action of the electric field and the magnetic field; the gas continuously enters the high-cyclotron ionization source and is ionized under the action of the vacuum equipment.

The present invention detects trace gases of pmol and below at different positions in the electrochemical field in situ, and realizes real-time correspondence between the amount and type of trace gases and electrochemical information, which can be used to explore the electrochemical reaction mechanism and catalyst properties of various systems, and provide important characterization support for the exploration of the mechanism of electrochemical systems that can produce gas (such as the field of electrocatalysis). The system has high quantitative accuracy, rich probe integration, fast response time, and convenient testing process. It can be widely used in related fields such as universities, scientific research institutions and related enterprises, and has broad commercial prospects.

Compared with the prior art, the present invention has the following beneficial effects:

The present invention has pioneered the technology of organically combining electrochemical probes with trace gas analysis, providing a powerful characterization tool for the mechanism exploration of various electrochemical systems. The gas production of such electrochemical systems is in the order of pmol or less, and conventional gas analyzers cannot test gas production of this order of magnitude in a vacuum environment. The electrochemical probe of the present invention can realize the integration of different electrochemical systems and perform in-situ real-time detection through a trace gas analyzer.

The probe provided by the present invention can realize multifunctional coupling such as integration of multiple electrochemical catalysts, electrochemical signal delivery and selective collection of electrochemical products, and can test various catalytic systems and various catalytic products, thereby increasing the applicability of the device.

The multi-channel array injection system can be used to analyze the electrochemical changes occurring in the overall electrochemical field in situ and in real time, and the generated trace gases can correspond to the applied voltage, voltage and other information in real time, which facilitates the analysis of microscopic interface changes in the electrochemical system.

The high cyclotron ionization source is used to make the ionized electrons show spiral motion through electromagnetic control, which increases the residence time of the electrons in the ion vacuum chamber, thereby increasing the ionization probability of the sample gas. Compared with the linear motion of electrons, the ionization rate of the sample gas with spiral motion of electrons can be increased by more than 2 orders of magnitude.

The high-cyclotron ionization ion source and the mass analyzer are vertically connected (i.e., the charged ions separated in the high-cyclotron ionization ion source are pulsed vertically into the mass analyzer). When the mass analyzer performs ion pulse injection testing, the ions can be ensured to be located in the same position, thereby improving the accuracy and reliability of ion mass analysis to more than 99.99%.

Using capillary connection, the multi-channel array injector uses the pressure difference between the inside and outside of the system to perform injection. After trace gas is generated, the mass spectrometer response time can reach milliseconds.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is a system structure diagram of an analysis system provided by the present invention;

FIG2 is a schematic diagram of the operation of a high cyclotron ionization ion source;

Figure 3 is a schematic diagram of the tip; the left side is a cross-sectional view, and the right side is a top view;

FIG4 is a schematic diagram of the structure of the sleeve (left) and the rotor (right).

Detailed ways

The present invention is described in detail below with reference to the accompanying drawings and embodiments.

Example 1

FIG1 is a schematic diagram of the structure of a fully automated electrochemical mass spectrometry analysis system provided by an embodiment of the present invention. As shown in FIG1 , the in-situ electrochemical trace product sampling and detection system includes:

Vacuum electrode sampling module: includes sampling probe electrode, electrochemical sample stage, first XYZ coordinate stage, displacement controller, potential controller and main controller (computer).

Trace gas analysis module: includes injection capillary, high cyclotron ionization source, vacuum equipment, mass analyzer and detection module.

The electrochemical sample stage is arranged on the first XYZ coordinate stage, and the first XYZ coordinate stage is connected to the displacement controller and the main controller, and is used to control the displacement of the electrochemical sample stage in three-dimensional space, so as to change the position (in three-dimensional space) of the electrochemical field and the sampling probe electrode in the electrochemical sample stage (in practical application, the sampling probe electrode can be fixed by setting a third XYZ coordinate stage). The sampling probe electrode, the potential controller and the main controller are connected in sequence.

The trace gas analysis module is connected to the hollow channel of the sampling probe electrode through an injection capillary, and the injection capillary can preferably use a quartz capillary. The injection capillary is also connected to a high-cyclotron ionization ion source, which is in turn connected to a mass analyzer and a detection module, and is connected to a vacuum device; the detection module is connected to a main controller.

Under the action of the vacuum equipment, the gas that selectively passes through the sampling probe electrode enters the high-cyclotron ionization source through the injection capillary. The gas is ionized by the high-cyclotron ionization source to form a charged ion beam. The charged particle beam enters the mass analyzer and is separated into charged particles of different masses. The detection module detects the current generated by the charged particles of different masses.

The sampling probe electrode has a surface tip wrapped by a multi-layer metal electrode and a selective membrane added inside. It is used to apply the electrochemical signal provided by the potential controller to the electrochemical field in the electrochemical sample stage, and collect the gas or volatile products in the electrochemical field and transmit them to the high cyclotron ionization ion source through a quartz capillary.

As shown in Figure 1-2, the high-cyclotron ionization ion source and the mass analyzer are both arranged in a vacuum metal cavity; and the high-cyclotron ionization ion source is connected to the sampling probe electrode and the mass analyzer, and includes electromagnetic control, ion acceleration electrode, electron acceleration electric field, electron emission filament and electromagnet; the electromagnetic control is used to adjust the magnetic field strength, and the electrons emitted by the electron emission filament are subjected to the interaction between the electric field and the magnetic field in the ionization chamber to spiral forward. After the sample enters the ionization chamber, it is perpendicular to the direction of the electrons. Compared with straight-line advancement, the electrons emitted by the spirally advancing electron emission filament have a long residence time in the cavity, and the number of electrons distributed in the space is large, which can increase the ionization rate of the sample by more than 2 orders of magnitude.

The mass analyzer uses time-of-flight or quadrupole. The mass analyzer is connected to the high-cyclotron ionization ion source through the slit of the cavity. By controlling the pulse signal, the charged ions generated by the high-cyclotron ionization source are prompted to enter the mass analyzer in a pulsed vertical manner. Compared with horizontal entry, vertical entry of ions can ensure that the ions enter the mass analyzer at the same position, and the mass analyzer's resolution accuracy for ions will be improved.

The detection module has both a non-gain ion detector and a gain ion detector. Conventional detection uses a non-gain ion detector with better stability. When detecting a smaller amount of gas, the gain ion detector can be turned on. Preferably, the non-gain ion detector in the detection module of the device uses a Faraday cup, and the gain ion detector uses an electron multiplier.

The inner diameter of the quartz capillary is preferably 3 μm or 5 μm. The interface of the quartz capillary connection is preferably 1/16 inch. The connection between the microporous quartz capillary and different devices is preferably sealed by using a 1/16 screw and a polyimide pressure ring; when sealing, the screw must be adjusted to ensure that the microporous quartz capillary cannot be pulled, and air and high-purity Ar are used to detect air tightness.

The injection system can be controlled by the XYZ console to operate a single sampling probe electrode in the electrochemical field to test the gas production at different positions; the injection can also be controlled by a multi-channel array injection system, which is made of peek material or stainless steel and consists of a sleeve, a rotor and a stepper motor. The sleeve is fixed on the second XYZ coordinate table, and the second XYZ coordinate table and the stepper motor are also connected to the displacement controller, which controls the rotation of the stepper motor's execution axis and the movement of the second XYZ coordinate table through the displacement controller.

As shown in FIG4 , the surface of the sleeve has a plurality of threaded holes evenly distributed according to the thread line and connected to the inner cavity of the sleeve, and a connecting capillary (microporous quartz capillary) is used to connect the sampling probe electrode to the threaded holes on the sleeve respectively; the rotor has an intermediate channel and a micropore connected to the intermediate channel is opened on the peripheral body, and the sampling capillary is connected to the intermediate channel of the rotor. The rotor moves in a spiral motion inside the sleeve under the action of the stepper motor, and at the same time drives the sleeve to descend at a uniform speed along the Z axis direction through the second XYZ coordinate table. At this time, the rotor will make a spiral upward motion relative to the sleeve, and the high cyclotron ionization ion source is also connected to the rotor using a sampling capillary. When the micropores on the rotor correspond to the threaded holes on the sleeve, a passage will be formed. At this time, the gas produced at a certain position in the electrochemical field will be pumped into the high cyclotron ionization ion source under the action of the vacuum equipment to realize the ionization of the gas, and then the charged particles of different masses are separated by the mass analyzer, and the current generated by the charged particles of different masses is detected by the detection module in the detection module.

The above describes the structure of the in-situ electrochemical trace product sampling and detection system proposed by the present invention, and the working method thereof will be described below.

Take the electrochemical signal and product analysis coupling test analysis of the products in the electrochemical catalytic process of copper catalyst as an example: before the test, the trace gas analysis module is first started and calibrated. Before the equipment is turned on, the vacuum chamber is first baked at high temperature to volatilize various impurities adsorbed in the vacuum chamber to create a high vacuum environment. After the baking is completed, the vacuum equipment is turned on. The specific process is to first turn on the pre-pump to provide a ^10-2 mbar operating environment for the molecular pump; then turn on the molecular pump, and when the vacuum chamber stabilizes to a vacuum degree of less than ^10-8 mbar, turn on the electron emission filament in the high cyclotron ionization ion source, and pass high-purity Ar through the quartz capillary, and record the mass40 ion current intensity; turn on the electromagnetic control and adjust the magnetic field strength. After the mass40 ion current intensity increases by 2 orders of magnitude, fix the corresponding parameters of the electromagnetic control.

Subsequently, the sampling probe electrode can be made of rigid glass capillaries or flexible materials such as carbon nanotubes and conductive rubber, which are also used for the tip probe. These materials are flexible, can adapt to different shapes of sample surfaces, and provide a certain conductivity.

The sampling probe electrode is preferably provided with a hollow capillary in the middle, which is used to collect the gas and volatile products produced by the reaction;

The sampling probe electrode is preferably filled with PTFE membrane to prevent water vapor molecules from passing through and ensure that the product gas is collected normally. Various polymer membranes can also be used inside. Polymer membranes with special pore structures or functional groups can achieve selective permeation of specific gases; metal organic frameworks MOF are a type of crystal structure composed of metal ions and organic ligands, with a controllable pore structure, which can be used to selectively permeate specific gases.

The tip of the sampling probe electrode is in an atmospheric pressure environment outside and a vacuum environment inside. When the tip is close enough to the substrate surface, the generated gas and volatile products can be quickly collected. The pressure difference between the inside and outside of the membrane can achieve complete collection of the products; when the amount of generated gas and volatile products is small, the size of the quartz capillary between the sampling probe electrode and the high cyclotron ionization ion source can be appropriately reduced or materials can be filled in the capillary to achieve the collection of trace products.

As shown in FIG3 , the surface of the sampling probe electrode tip is preferably coated with Au and Pt metal. The sampling probe electrode tip can be made of a variety of electrode materials, which have excellent electrical conductivity and chemical stability and are suitable for the study of many electrochemical reactions. Carbon nanotubes have unique electrochemical properties, with high conductivity and excellent chemical stability. The tip of the carbon nanotube can be used for high-resolution scanning imaging. Alternatively, some nanostructured materials, such as metal nanoparticles or nanowires, can also be used as electrode tips. These materials generally provide higher surface activity and more sensitive electrochemical response. In some electrochemical systems, the tip can be made of non-conductive materials, such as glass fibers. Non-conductive tips are generally used to measure potential distribution or ion concentration distribution in solutions. The choice of tip material depends on the specific research needs, sample properties, and the type of electrochemical reaction being studied. Different tip materials may produce different signal responses and imaging effects.

The electrode size at the tip of the sampling probe electrode is generally preferred to be in the micron level; the electrode size at the tip of the sampling probe electrode is usually in the micron or nanometer level, and the tip size is one of the key factors that determine its spatial resolution and performance. The geometry and size of the tip will directly affect the resolution and the ability to perceive the microstructure of the substrate surface. The tip has many characteristics, such as negligible ohmic drop, small double layer capacitor charging process, and high mass transfer rate.

There are reference electrode and auxiliary electrode at the base of the electrochemical sample stage, forming a three-electrode system with the sampling probe electrode.

At the beginning of the test, the electrolyte, substrate and catalyst are added to the electrochemical sample table, and the outer metal electrode layer of the tip of the sampling probe electrode is connected to the potential controller. Two different potentials are applied simultaneously between the sampling probe electrode and the substrate through the potential controller to detect the dynamics of the electrochemical reaction and the changes in surface properties. The data recording project of the trace gas analysis module is turned on through the system controller to observe the concentration and type of gas production. The potential controller can accurately control and measure the voltage and current of the substrate and the probe to monitor different electrochemical reactions; the sampling probe electrode can be set to an array type, and then form an array tip to identify and collect electrochemical signals and products at multiple points on the substrate. The array tip can be connected to the trace gas analysis module at the same time, and then the products at multiple points can be collected and detected.

The base of the electrochemical sample stage is connected to multiple first stepper motors, the first XYZ coordinate stage and the displacement controller in sequence to move the base. The base surface is the X, Y plane, and Z represents the vertical direction from the sampling probe electrode to the base surface. The probe can scan in the X, Y and Z directions, monitor the current signals corresponding to different coordinate positions, and enable the sampling electrode probe to scan and identify different parts of the base; multiple first stepper motors, the first XYZ coordinate stage and the displacement controller are all uniformly controlled by the main controller to achieve micron-level movement.

The main controller controls the potential and moves the substrate, and analyzes, identifies and images the current signals generated by the sample and the sampling probe electrode in the electrochemical sample stage. The acquired raw current or potential data exists in the form of images or data, where each data point corresponds to a position on the sample surface. At the same time, the trace gas analysis module records the production, rate and type of product gas. Through data processing, it is possible to couple the electrochemical signals at different positions in the electrochemical field with the total amount, rate and type of products in real time in situ, and use appropriate electrochemical models to interpret the experimental results, which can provide a deeper understanding of the electrochemical reaction mechanism.

After completing the preparation of the sampling probe electrode and the assembly of the trace gas analysis module, the electrochemical catalytic process of the copper catalyst was analyzed. When the vacuum degree of the vacuum chamber reaches ^10-8 ~ ^10-9 mbar, the sampling module is connected to the gas analysis module, and a microcurrent is applied for testing and gas information is recorded at the same time. The gas production can be detected at the pmol level, and the result is consistent with the theoretical yield. As the applied electrochemical signal changes, the gas production also changes. The equipment is still running stably after 72 hours, and the gas product can still be stably detected after applying the electrochemical signal to the sampling probe electrode. By optimizing the ion source parameters and the magnetic field strength of the electromagnet, and using vacuum equipment with a higher vacuum degree, the gas production at the fmol level can be detected.

The above tests have proved that the sampling and detection system provided by the present invention can realize fmol-level gas production test, which will help practitioners and scientific researchers in the field of energy catalysis to conduct in-depth research on trace product systems; the equipment described in the present invention can realize the coupling of electrochemical signals and product signals, which is helpful to realize in-situ real-time analysis of catalytic systems; the equipment described in the present invention can operate stably for a long time; the equipment of the present invention also has a highly integrated sampling probe electrode, which is suitable for a variety of electrochemical systems, and the modular assembly is convenient and fast, and has strong applicability.

Comparative Example 1

The electrochemical catalytic process of copper catalyst was tested using a sampling probe without a metal layer at the tip and a gas analyzer without a gas selective permeation material in the hollow channel and a high cyclotron ionization ion source without an electromagnet. When the vacuum degree of the vacuum chamber reached ^10-8 to ^10-9 mbar, the capillary was immersed and current was applied for testing and gas information was recorded at the same time. After 5 seconds, the capillary was blocked and the water content increased from less than 1% to more than 90%. Further observation of the increase in water content revealed that the detected gas was a battery, and the entry of water would also damage the filament and reduce the service life of the ion source.

Comparative Example 2

The electrochemical catalytic process of copper catalyst was tested using a sampling probe with a metal layer at the tip and a gas selective permeation material set in the hollow channel and a gas analyzer without an electromagnet. When the vacuum degree of the vacuum chamber reached ^10-8 ~ ^10-9 mbar, the capillary was connected to the electrochemical probe, and current was applied for testing and gas information was recorded at the same time. It was found that with the change of current, when the theoretical gas production was pmol, the gas detected by the gas analyzer did not change significantly compared with the baseline before the test. That is, the gas production at the pmol level could not be detected.

The above are only preferred implementations of the patent of the present invention. It should be pointed out that ordinary technicians in this technical field can make several improvements and modifications without departing from the principles of the patent of the present invention. These improvements and modifications should also be regarded as the protection scope of the patent of the present invention.

Claims (10)

1. A sampling probe electrode, characterized in that it comprises a sampling probe electrode body having a tip and a hollow channel, wherein the tip is coated with a plurality of mutually insulated metal electrode layers, and the hollow channel is filled with a filling material for selective gas permeation, wherein the filling material comprises a polymer film and/or a metal organic framework (MOF) material. 2 . The sampling probe electrode according to claim 1 , wherein the sampling probe electrode body is a glass capillary. 3. The sampling probe electrode according to claim 1, characterized in that the tip is any one of carbon nanotubes, conductive rubber, conductive nanometal materials, and non-conductive materials; Wherein, the conductive nanometal material includes metal nanoparticles or metal nanowires; and the non-conductive material includes glass fibers. 4 . The sampling probe electrode according to claim 1 , wherein the metal electrode layer comprises an Au electrode layer and a Pt electrode layer. 5. An in-situ electrochemical trace sampling detection system, characterized in that it includes a main controller, a vacuum electrode sampling module and a trace gas analysis module; The vacuum electrode sampling module comprises an electrochemical sample stage, a potential controller, a first XYZ coordinate stage, a displacement controller and at least one sampling probe electrode according to any one of claims 1 to 5; The electrochemical sample stage is used to place the electrochemical test sample, and a reference electrode and an auxiliary electrode are provided at the base; The potential controller is connected to the metal electrode layer of the sampling probe electrode and the main controller, and is used to control the electrochemical parameters of each electrode in the electrochemical reaction system; The electrochemical sample stage is arranged on a first XYZ coordinate stage, and the first XYZ coordinate stage is connected to a displacement controller and a main controller, and is used to control the displacement of the electrochemical sample stage in a three-dimensional space to change the position of the sampling probe electrode in the electrochemical field; The sampling probe electrode is used to apply the electrochemical signal provided by the potential controller to the electrochemical field in the electrochemical sample stage, and can allow the gas generated by the electrochemical reaction to selectively permeate; The trace gas analysis module is connected to the main controller and the sampling probe electrode, and is used to collect the gas transmitted through the sampling probe electrode and to ionize and detect the transmitted gas. 6. The in-situ electrochemical trace sampling and detection system according to claim 5, characterized in that the trace gas analysis module comprises an injection capillary, a high cyclotron ionization ion source, a vacuum device, a mass analyzer and a detection module; The injection capillary is connected to the hollow channel of the sampling probe electrode and the high cyclotron ionization ion source, which is in turn connected to the mass analyzer and the detection module, and is also connected to the vacuum device; the detection module is connected to the main controller; Under the action of the vacuum equipment, the gas that selectively passes through the sampling probe electrode enters the high-cyclotron ionization source through the injection capillary. The gas is ionized by the high-cyclotron ionization source to form a charged ion beam. The charged particle beam enters the mass analyzer and is separated into charged particles of different masses. The detection module detects the current generated by the charged particles of different masses. 7. The in-situ electrochemical micro-sampling detection system according to claim 5, characterized in that there are multiple sampling probe electrodes and they are distributed in an array. 8. The in-situ electrochemical micro-sampling detection system according to claim 7, characterized in that the vacuum electrode sampling module further comprises a multi-channel array injector; The multi-channel array injector comprises a sleeve, a rotor arranged in the sleeve, and a stepper motor for driving the rotor to rotate in the sleeve; the sleeve is fixed on the second XYZ coordinate stage, and the second XYZ coordinate stage and the stepper motor are also connected to the displacement controller, and the displacement controller controls the rotation of the execution shaft of the stepper motor and the movement of the second XYZ coordinate stage; Among them, a plurality of threaded holes connected to the inner cavity of the sleeve are distributed along the thread line on the sleeve, and the sampling probe electrode is connected to the threaded hole by using a connecting capillary; the rotor has an intermediate channel and a microhole connected to the intermediate channel is opened on the peripheral body, and the sampling capillary is connected to the intermediate channel of the rotor; The stepper motor drives the rotor to make spiral motion in the sleeve, and the second XYZ coordinate table drives the sleeve to move along the Z direction. When the micropores on the rotor correspond to the threaded holes on the sleeve, the gas produced at a certain position in the electrochemical field will be pumped to the high-cyclotron ionization ion source to achieve gas ionization. After the charged particles of different masses are separated by the mass analyzer, the current generated by the charged particles of different masses is detected by the detection module. 9. The in-situ electrochemical micro-sampling detection system according to claim 6 or 8, characterized in that the charged ions separated in the high-cyclotron ionization ion source enter the mass analyzer vertically in a pulsed manner. 10. The in-situ electrochemical micro-sampling detection system according to claim 6 is characterized in that an electromagnet is provided in the high-cyclotron ionization ion source, and the electrons emitted in the high-cyclotron ionization source move in a spiral motion under the action of the electric field and the magnetic field; the gas continuously enters the high-cyclotron ionization ion source and is ionized under the action of the vacuum equipment.