Microcell scanning electrochemical testing device and method for in-situ hydrogen permeation sample

Abstract

The invention discloses a micro-area scanning electrochemical testing device and method for an in-situ hydrogen permeation sample, and relates to the technical field of adaptability evaluation of a solid conductive material in a hydrogen environment. The device comprises a direct-current power supply, an electrochemical workstation and a double-electrolytic-tank main body, the double-electrolytic-tank main body is composed of a first electrolytic tank and a second electrolytic tank, a sample clamping device is arranged between the first electrolytic tank and the second electrolytic tank and clamps and fixes a sample to be tested, the first electrolytic tank is provided with a first auxiliary electrode, and the second electrolytic tank is provided with a second auxiliary electrode. The second electrolytic tank is provided with a second auxiliary electrode, a reference electrode and an ultramicro probe, one end of the ultramicro probe is connected with a high-resolution three-dimensional positioning device, and the high-resolution three-dimensional positioning device is used for driving the ultramicro probe to move and scan the test surface. By utilizing the device, the electrochemical morphology change condition of the surface microcell of the in-situ detection material can be quickly and accurately obtained in the hydrogen permeation test process, so that the adaptability evaluation in the hydrogen environment is more accurate.

Description

Technical Field

[0001] The invention relates to the technical field of adaptability evaluation of solid conductive materials in a hydrogen environment, and in particular to a device and method for in-situ hydrogen permeation sample micro-area scanning electrochemical testing. Background Art

[0002] In a high-pressure hydrogen environment, hydrogen can easily enter the interior of metal materials through adsorption and penetration, and locally accumulate in metal materials through diffusion, resulting in a decrease in the performance of metal materials, affecting pipeline safety and the development of the hydrogen pipeline industry. With the increasing severity of global climate change and environmental problems, the development of clean energy has become a key way to solve the energy crisis and achieve sustainable development. Hydrogen energy, with its clean and efficient characteristics, is regarded as an important direction for the transformation of future energy structures. However, the widespread application of hydrogen energy faces many technical challenges, especially the storage and transportation of hydrogen, which has become a key bottleneck restricting the development of hydrogen energy. In the application of hydrogen energy, the interaction between hydrogen and materials may lead to the degradation of material properties, including hydrogen embrittlement, hydrogen corrosion and hydrogen damage. These phenomena not only shorten the service life of the material, but also pose a serious threat to the safety of the system. Therefore, in-depth research on the hydrogen permeation performance of materials, especially the changes in the micro-corrosion performance of materials caused by hydrogen, is of great significance for the development of new materials that can resist hydrogen damage. As an important means to evaluate the hydrogen permeation resistance of materials, hydrogen permeation testing can quantify the ability of hydrogen to pass through materials, thereby evaluating the stability and reliability of materials in hydrogen environments. Micro-area corrosion electrochemical measurements of in-situ hydrogen permeable materials using micro-area scanning electrochemical microscopy can further reveal the interaction mechanism between materials and hydrogen molecules, providing a scientific basis for the optimization of material performance. In this process, it is necessary to have a deep understanding of the microstructure and macroscopic properties of the materials in order to develop new hydrogen storage and hydrogen transport materials with excellent resistance to hydrogen permeation. These materials must not only have efficient hydrogen storage and transportation capabilities, but also have good electrochemical stability and mechanical strength to meet the needs of practical applications. In short, in-depth exploration of the hydrogen permeation properties of materials and detection of nanoscale changes on the surface of in-situ hydrogen permeable materials are effective ways to solve technical problems in the process of hydrogen storage and transportation, and are of great significance to promoting the development of hydrogen energy industrialization.

[0003] The commonly used hydrogen permeation test devices are developed based on the electrochemical hydrogen permeation device invented by Devanathan-Stachurski in 1962. The test device includes two electrolytic cells that are not connected to each other. One is a hydrogen charging tank connected to a DC power supply to charge the sample with hydrogen, and the other is a hydrogen escape tank connected to an electrochemical measuring instrument with a three-electrode system to measure the escaped hydrogen atoms to obtain the hydrogen permeability coefficient of the material. Scanning Electrochemical Microscopy (SECM) is an advanced electrochemical analysis method and a sign of the deepening of electrochemical research from the macroscopic to the microscopic level. SECM technology uses very small electrodes (probes) to scan near the sample and measure the electrochemical current given by the oxidation or reduction of substances in the micro area. The resolution can reach tens of nanometers, and the electrochemical morphology characteristics of the material surface can be mastered.

[0004] Micro-area scanning has the problem of not being able to perform continuous testing during hydrogen permeation testing, which makes the evaluation of the adaptability of conductive materials in hydrogen environments inaccurate and needs to be further improved. Summary of the invention

[0005] The purpose of the present invention is to make up for the shortcomings of existing testing technology and provide a device and method for in-situ hydrogen permeation sample micro-area scanning electrochemical testing. By using this device, the morphological changes of the in-situ detection material surface micro-area electrochemistry can be quickly and accurately obtained during the hydrogen permeation test, thereby ensuring a more accurate evaluation of the material's adaptability in a hydrogen environment.

[0006] The first object of the present invention is to provide an in-situ hydrogen permeation sample micro-area scanning electrochemical testing device, comprising a DC power supply, an electrochemical workstation and a dual electrolytic cell body, wherein the dual electrolytic cell body is composed of a first electrolytic cell and a second electrolytic cell: A sample clamping device is provided between the first electrolytic cell and the second electrolytic cell, one end of the sample clamping device is connected to the side wall of the first electrolytic cell, and the other end of the sample clamping device is connected to the side wall of the second electrolytic cell, and the sample clamping device clamps and fixes the sample to be tested; The first electrolytic cell is filled with a first electrolyte, the liquid level of the first electrolyte in the first electrolytic cell is higher than the height of the sample clamping device, and a first auxiliary electrode is arranged in the first electrolytic cell, and the lower end of the first auxiliary electrode extends below the liquid level of the first electrolyte; The second electrolytic cell is filled with a second electrolyte, the liquid level of the second electrolyte in the second electrolytic cell is higher than the height of the sample clamping device, the second electrolytic cell is provided with a second auxiliary electrode, and the lower end of the second auxiliary electrode extends below the liquid level of the second electrolyte; A reference electrode and an ultramicroprobe are also provided in the second electrolytic cell, and the lower end of the reference electrode extends below the liquid surface of the second electrolyte; One end of the ultra-micro probe is in contact with the test surface of the sample to be tested, and the other end of the ultra-micro probe is connected to a high-resolution three-dimensional positioning device, and the high-resolution three-dimensional positioning device is used to drive the ultra-micro probe to move and scan the test surface; The first auxiliary electrode, the second auxiliary electrode, the reference electrode, the ultramicroprobe and the sample to be tested can be electrically connected to the direct current power supply or the electrochemical workstation through wires.

[0007] In a specific embodiment of the present invention, the sample clamping device includes a first liquid guide tube, a second liquid guide tube and two clamping flanges, one end of the first liquid guide tube is connected to the side wall of the first electrolytic cell, one end of the second liquid guide tube is connected to the side wall of the second electrolytic cell, the two clamping flanges are respectively fixed on the first liquid guide tube and the second liquid guide tube, the sample to be tested is fixed between the two clamping flanges, the two clamping flanges are connected by bolts, and one end of the ultramicroprobe is arranged in the second liquid guide tube and contacts the test surface of the sample to be tested.

[0008] In a specific embodiment of the present invention, the ultramicroprobe is L-shaped.

[0009] In a specific embodiment of the present invention, both the first electrolytic cell and the second electrolytic cell are provided with a charging and discharging gas pipe.

[0010] In a specific embodiment of the present invention, a first fixing hole is provided above the first electrolytic cell, and the first auxiliary electrode is transitionally matched with the first fixing hole.

[0011] In a specific embodiment of the present invention, two second fixing holes are arranged above the second electrolytic cell, and the second auxiliary electrode and the reference electrode are both transitionally matched with the second fixing holes.

[0012] In a specific embodiment of the present invention, a scanning active hole is arranged above the second electrolytic cell, and the lower end of the ultramicroprobe passes through the scanning active hole and extends into the second electrolytic cell.

[0013] In a specific embodiment of the present invention, the scanning active hole is a square hole or a round hole.

[0014] A second object of the present invention is to provide an in-situ hydrogen permeation sample micro-area scanning electrochemical testing method, which is implemented using the above-mentioned in-situ hydrogen permeation sample micro-area scanning electrochemical testing device, comprising the following steps: Clamp the sample to be tested in the sample clamping device; Connecting the first auxiliary electrode to the positive electrode of the DC power supply and placing the first auxiliary electrode in the first electrolytic cell; placing the ultramicroprobe in the second electrolytic cell and making the ultramicroprobe contact with the detection surface of the sample to be tested; Connecting the negative electrode of the DC power supply and the electrochemical workstation to the ultra-microprobe through a wire, installing the ultra-microprobe on a high-resolution three-dimensional positioning device, and extending the ultra-microprobe into the second electrolytic cell to contact the detection surface of the sample to be tested; Inject two-thirds of the volume of the second electrolyte into the second electrolytic cell, and make the second electrolyte cover the test sample, start the electrochemical workstation, and test the current density; Inject two-thirds of the volume of the first electrolyte into the first electrolytic cell, and make the first electrolyte cover the test sample, start the DC power supply, and charge hydrogen; After the hydrogen filling is completed, the sample to be tested is connected to the electrochemical workstation through a wire, and the high-resolution three-dimensional positioning device is started to drive the ultra-micro probe to move and scan the detection surface of the sample to be tested.

[0015] In a specific embodiment of the present invention, argon gas is introduced into the first electrolytic cell and the second electrolytic cell through the gas charging and discharging pipes during hydrogen charging.

[0016] Compared with the prior art, the present invention has the following beneficial effects: 1. The present invention provides an in-situ hydrogen permeation sample micro-area scanning electrochemical testing device and method, which is helpful to realize stable online scanning electrochemical testing of hydrogen-charged samples; 2. The present invention improves the accuracy and reliability of scanning electrochemical testing by designing the ultramicroprobe into an L-shape and setting a vertical detection surface; 3. The present invention also realizes online in-situ detection of hydrogen permeation samples, which can quickly and accurately obtain the morphological changes of the electrochemical micro-area on the surface of the in-situ hydrogen permeation material, avoid the errors caused by discontinuous testing, and ensure that the adaptability evaluation of the material in a hydrogen environment is more accurate. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Attached Figure 1 It is a schematic diagram of the micro-area scanning electrochemical in-situ test principle of a specific embodiment of the present invention; Attached Figure 2 It is a schematic structural diagram of the in-situ hydrogen permeation sample micro-area scanning electrochemical testing device of the present invention.

[0018] In the accompanying drawings, the names of the components represented by the reference numerals are as follows: 1. First electrolytic cell; 2. Second electrolytic cell; 3. Sample holding device; 4. First auxiliary electrode; 5. Second auxiliary electrode; 6. Reference electrode; 7. Ultra-micro probe; 8. Gas charging and discharging tubes; 9. Sample to be tested; 10. High-resolution three-dimensional positioning device; 11. DC power supply; 12. Electrochemical workstation. DETAILED DESCRIPTION

[0019] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions 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 of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0020] It should be noted that all directional indications in the embodiments of the present invention (such as up, down, left, right, front, back, etc.) are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0021] In the present invention, unless otherwise clearly specified and limited, the terms "connection", "fixation", etc. should be understood in a broad sense. For example, "fixation" 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 an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0022] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or suggesting their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in the field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0023] Example

[0024] Based on the attached Figure 1-2, an in-situ hydrogen permeation sample micro-area scanning electrochemical testing device, comprising a DC power supply 11, an electrochemical workstation 12 and a dual electrolytic cell body, the dual electrolytic cell body consisting of a first electrolytic cell 1 and a second electrolytic cell 2, a sample clamping device 3 is arranged between the first electrolytic cell 1 and the second electrolytic cell 2, one end of the sample clamping device 3 is connected to the side wall of the first electrolytic cell 1, and the other end of the sample clamping device 3 is connected to the side wall of the second electrolytic cell 2, and the sample clamping device 3 clamps and fixes a sample 9 to be tested; The first electrolytic cell 1 is filled with a first electrolyte, the liquid level of the first electrolyte in the first electrolytic cell 1 is higher than the height of the sample holding device 3, and a first auxiliary electrode 4 is arranged in the first electrolytic cell 1, and the lower end of the first auxiliary electrode 4 extends below the liquid level of the first electrolyte; The second electrolytic cell 2 is filled with a second electrolyte, the liquid level of the second electrolyte in the second electrolytic cell 2 is higher than the height of the sample holding device 3, and the second electrolytic cell 2 is provided with a second auxiliary electrode 5, the lower end of the second auxiliary electrode 5 extends below the liquid level of the second electrolyte; A reference electrode 6 and an ultramicroprobe 7 are also provided in the second electrolytic cell 2, and the lower end of the reference electrode 6 extends below the liquid surface of the second electrolyte; One end of the ultra-micro probe 7 contacts the test surface of the sample 9 to be tested, and the other end of the ultra-micro probe 7 is connected to a high-resolution three-dimensional positioning device 10, which is used to drive the ultra-micro probe 7 to move and scan the test surface; The first auxiliary electrode 4 , the second auxiliary electrode 5 , the reference electrode 6 , the ultramicroprobe 7 and the sample to be tested 9 can be electrically connected to a direct current power source 11 or an electrochemical workstation 12 via wires.

[0025] Based on the above structure, the embodiment of the present invention realizes online in-situ detection of hydrogen permeation samples, can quickly and accurately obtain the morphological changes of the electrochemical micro-area on the surface of the in-situ hydrogen permeation material, avoid the errors caused by discontinuous testing, and ensure that the adaptability evaluation of the material in a hydrogen environment is more accurate.

[0026] In some instances, the sample clamping device 3 includes a first liquid conduit, a second liquid conduit and two clamping flanges, one end of the first liquid conduit is connected to the side wall of the first electrolytic cell 1, one end of the second liquid conduit is connected to the side wall of the second electrolytic cell 2, the two clamping flanges are respectively fixed on the first liquid conduit and the second liquid conduit, the sample to be tested 9 is fixed between the two clamping flanges, the two clamping flanges are connected by bolts, and one end of the ultramicro probe 7 is arranged in the second liquid conduit and contacts the test surface of the sample to be tested 9.

[0027] In some examples, a sealing gasket is disposed between the two clamping flanges.

[0028] In some examples, the ultra-microprobe 7 is L-shaped, which improves the accuracy and reliability of scanning electrochemical testing.

[0029] In some examples, both the first electrolytic cell 1 and the second electrolytic cell 2 are provided with a gas charging and discharging pipe 8 .

[0030] In some examples, a first fixing hole is provided above the first electrolytic cell 1 , and the first auxiliary electrode 4 is transitionally matched with the first fixing hole.

[0031] In some examples, two second fixing holes are provided above the second electrolytic cell 2, and the second auxiliary electrode 5 and the reference electrode 6 are both transitionally matched with the second fixing holes.

[0032] In some examples, a scanning active hole is provided above the second electrolytic cell 2 , and the lower end of the ultramicroprobe 7 passes through the scanning active hole and extends into the second electrolytic cell 2 .

[0033] In some examples, the scanning active aperture is a square aperture or a round aperture.

[0034] The in-situ hydrogen permeation sample micro-area scanning electrochemical testing method is implemented using the above-mentioned in-situ hydrogen permeation sample micro-area scanning electrochemical testing device, and the method comprises the following steps: Clamp the sample 9 to be tested in the sample clamping device 3; Connect the first auxiliary electrode 4 to the positive electrode of the DC power supply 11, and place the first auxiliary electrode 4 in the first electrolytic cell 1; The ultramicroprobe 7 is placed in the second electrolytic cell 2, and the ultramicroprobe 7 is brought into contact with the detection surface of the sample to be tested 9; Connect the negative electrode of the DC power supply 11 and the electrochemical workstation 12 to the ultra-microprobe 7 through a wire, install the ultra-microprobe 7 on the high-resolution three-dimensional positioning device 10, and extend the ultra-microprobe 7 into the second electrolytic cell 2 to contact the detection surface of the sample 9 to be tested; Inject two-thirds of the volume of the second electrolyte into the second electrolytic cell 2, and make the second electrolyte cover the test sample 9, start the electrochemical workstation 12, and test the current density; Inject two-thirds of the volume of the first electrolyte into the first electrolytic cell 1, and make the first electrolyte cover the test sample 9, start the DC power supply 11, and charge hydrogen; After the hydrogen charging is completed, the sample to be tested 9 is connected to the electrochemical workstation 12 through a wire, and the high-resolution three-dimensional positioning device 10 is started to drive the ultra-micro probe 7 to move and scan the detection surface of the sample to be tested 9.

[0035] In some examples, argon gas is introduced into the first electrolytic cell 1 and the second electrolytic cell 2 through the gas charging and discharging pipe 8 during hydrogen charging.

[0036] In the scanning electrochemical test of the embodiment of the present invention, the test sample 9 and the electrolyte do not need to be changed, and the electrode system connection is different. At this time, the probe is mostly a working electrode, and the test sample 9 and the first auxiliary electrode 4 and the second auxiliary electrode 5 are used as a pair of auxiliary electrodes, and the reference electrode 6 remains unchanged.

[0037] In the embodiment of the present invention, the first electrolyte and the second electrolyte are conventional electrolytes, which can be selected according to the characteristics of the sample to be tested 9. The first electrolyte at the hydrogen charging end provides hydrogen ions, which are adsorbed on the surface of the sample to be tested 9 and converted into hydrogen atoms under the action of an applied potential and enter the interior of the sample to be tested 9. The second electrolyte at the hydrogen escape end serves to conduct ions. Different electrolytes can have a strong corrosive effect on the sample to be tested 9. A test loop is formed at the test end of the electrochemical workstation 12 to perform scanning electrochemical testing, which helps to achieve stable online scanning electrochemical testing of hydrogen-charged samples.

[0038] The above descriptions are only optional embodiments of the present invention, and are not intended to limit the patent scope of the present invention. All equivalent structural changes made using the contents of the present invention's specification and drawings, or directly / indirectly applied in other related technical fields, are included in the patent protection scope of the present invention.

Claims

1. An in-situ hydrogen permeation sample micro-area scanning electrochemical testing device, comprising a DC power supply, an electrochemical workstation and a dual electrolytic cell body, wherein the dual electrolytic cell body consists of a first electrolytic cell and a second electrolytic cell, and is characterized in that: A sample clamping device is provided between the first electrolytic cell and the second electrolytic cell, one end of the sample clamping device is connected to the side wall of the first electrolytic cell, and the other end of the sample clamping device is connected to the side wall of the second electrolytic cell, and the sample clamping device clamps and fixes the sample to be tested; The first electrolytic cell is filled with a first electrolyte, the liquid level of the first electrolyte in the first electrolytic cell is higher than the height of the sample clamping device, and a first auxiliary electrode is arranged in the first electrolytic cell, and the lower end of the first auxiliary electrode extends below the liquid level of the first electrolyte; The second electrolytic cell is filled with a second electrolyte, the liquid level of the second electrolyte in the second electrolytic cell is higher than the height of the sample clamping device, the second electrolytic cell is provided with a second auxiliary electrode, and the lower end of the second auxiliary electrode extends below the liquid level of the second electrolyte; A reference electrode and an ultramicroprobe are also provided in the second electrolytic cell, and the lower end of the reference electrode extends below the liquid surface of the second electrolyte; One end of the ultra-micro probe is in contact with the test surface of the sample to be tested, and the other end of the ultra-micro probe is connected to a high-resolution three-dimensional positioning device, and the high-resolution three-dimensional positioning device is used to drive the ultra-micro probe to move and scan the test surface; The first auxiliary electrode, the second auxiliary electrode, the reference electrode, the ultramicroprobe and the sample to be tested can be electrically connected to the direct current power supply or the electrochemical workstation through wires.

2. The in-situ hydrogen permeation sample micro-area scanning electrochemical testing device according to claim 1, characterized in that: The sample clamping device includes a first liquid conduit, a second liquid conduit and two clamping flanges, one end of the first liquid conduit is connected to the side wall of the first electrolytic cell, one end of the second liquid conduit is connected to the side wall of the second electrolytic cell, the two clamping flanges are respectively fixed on the first liquid conduit and the second liquid conduit, the sample to be tested is fixed between the two clamping flanges, the two clamping flanges are connected by bolts, and one end of the ultramicro probe is arranged in the second liquid conduit and contacts the test surface of the sample to be tested.

3. The device for in-situ hydrogen permeation sample micro-area scanning electrochemical testing according to claim 2, characterized in that: The ultramicroprobe is L-shaped.

4. The device for in-situ hydrogen permeation sample micro-area scanning electrochemical testing according to claim 1, characterized in that: The first electrolytic cell and the second electrolytic cell are both provided with charging and discharging pipes.

5. The micro-area scanning electrochemical testing device for in-situ hydrogen permeation samples according to claim 1, characterized in that: A first fixing hole is arranged above the first electrolytic cell, and the first auxiliary electrode is transitionally matched with the first fixing hole.

6. The in-situ hydrogen permeation sample micro-area scanning electrochemical testing device according to claim 1, characterized in that: Two second fixing holes are arranged above the second electrolytic cell, and the second auxiliary electrode and the reference electrode are both transitionally matched with the second fixing holes.

7. The device for in-situ hydrogen permeation sample micro-area scanning electrochemical testing according to claim 1, characterized in that: A scanning activity hole is arranged above the second electrolytic cell, and the lower end of the ultra-micro probe passes through the scanning activity hole and extends into the second electrolytic cell.

8. The device for in-situ hydrogen permeation sample micro-area scanning electrochemical testing according to claim 7, characterized in that: The scanning active hole is a square hole or a round hole.

9. A method for in-situ hydrogen permeation sample micro-area scanning electrochemical testing, implemented by using the in-situ hydrogen permeation sample micro-area scanning electrochemical testing device according to any one of claims 1 to 8, characterized in that: The following steps are involved: Clamp the sample to be tested in the sample clamping device; Connecting the first auxiliary electrode to the positive electrode of the DC power supply and placing the first auxiliary electrode in the first electrolytic cell; placing the ultramicroprobe in the second electrolytic cell and making the ultramicroprobe contact with the detection surface of the sample to be tested; Connecting the negative electrode of the DC power supply and the electrochemical workstation to the ultra-micro probe through a wire, installing the ultra-micro probe on a high-resolution three-dimensional positioning device, and extending the ultra-micro probe into the second electrolytic cell to contact the detection surface of the sample to be tested; Inject two-thirds of the volume of the second electrolyte into the second electrolytic cell, and make the second electrolyte cover the test sample, start the electrochemical workstation, and test the current density; Inject two-thirds of the volume of the first electrolyte into the first electrolytic cell, and make the first electrolyte cover the test sample, start the DC power supply, and charge hydrogen; After the hydrogen filling is completed, the sample to be tested is connected to the electrochemical workstation through a wire, and the high-resolution three-dimensional positioning device is started to drive the ultra-micro probe to move and scan the detection surface of the sample to be tested.

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