Sample holder system for transmission electron microscope in in-situ freezing variable-temperature environment

Abstract

The invention relates to a sample rod system for an in-situ freezing variable-temperature environment transmission electron microscope, and belongs to the technical field of in-situ characterization of nanometer material transmission electron microscopes. The device comprises an airtight miniature sample table for manufacturing a liquid environment under high vacuum, a temperature-variable metal heat conduction wire for manufacturing the temperature of liquid helium and liquid nitrogen, a liquid / gas guide pipe for manufacturing a required gas or liquid detection environment, and a Dewar tank for storing the liquid helium and liquid nitrogen, the temperature of liquid helium or liquid nitrogen in the Dewar tank is transmitted to a to-be-tested sample in the airtight miniature sample table in a heat conduction manner through the variable-temperature metal heat conduction wire, so that in-situ freezing is realized; working liquid or working gas in the working liquid device or the working gas device is conveyed to the airtight miniature sample table through the liquid / gas guide pipe, so that the sample maintains a required gas or liquid detection environment. The system disclosed by the invention can be suitable for real-time transmission electron microscope detection of chemical reaction in an in-situ freezing variable-temperature environment.

Description

Technical Field

[0001] The invention discloses a sample rod system for an in-situ freezing temperature-variable environment transmission electron microscope, belonging to the technical field of in-situ characterization of nano material transmission electron microscope. Background Art

[0002] Materials will show various changes in physical and chemical properties under the influence of changes in the external environment, and these changes are of great significance to the practical application of materials. The performance of materials depends not only on their intrinsic composition and structure, but also on their behavior under external conditions such as temperature, gas / liquid environment, bias voltage, etc. The interaction between various external field environments and materials is the root cause of material performance and structural changes at the nanoscale or even atomic scale. Whether the microstructural evolution process of materials under the external environment and various external fields can be detected in situ at the nanoscale or even atomic scale has become the key to exploring the physical and chemical life characteristics of materials. In-situ technology is of great significance to the microscopic characterization of materials, and provides a powerful means for real-time and dynamic research on the structure and performance of materials under working or actual use conditions. Using these technologies, researchers can have a deeper understanding of the response and changes of materials in practical applications, thereby optimizing the design and application of materials. By conducting in-situ studies on materials under actual use conditions, material design and preparation processes can be optimized in a targeted manner based on the observed structure-performance relationship. Therefore, developing in-situ, synchronous, and dynamic monitoring methods at the atomic scale and improving the ultimate resolution of observation technology under environmental influences has become one of the important research contents in the current microstructure characterization technology project.

[0003] In-situ transmission electron microscopy is an advanced microscopic technique that can observe and characterize materials in real time while they are undergoing chemical reactions or physical processes. This technique is of great significance for a deep understanding of the dynamic behavior and microscopic mechanisms of materials in practical applications. In-situ transmission electron microscopy analysis technology can study the correlation between the composition structure and physical and chemical properties of materials in real time, in situ, and dynamically under external field conditions such as vacuum, gas phase, liquid phase, mechanics, electrochemistry, and thermal. At the same time, it can also reveal the microscopic mechanisms and dynamic behaviors inside the material. It has broad application prospects in catalytic reaction research, material mechanical properties analysis, phase change mechanism exploration, new material synthesis, and electronic and optical property research.

[0004] However, in the prior art, there is no sample auxiliary device that can directly introduce a gas environment and a liquid environment into a high vacuum environment of a transmission electron microscope. Summary of the invention

[0005] Aiming at the problem that it is impossible to directly introduce a gas environment and a liquid environment into a high vacuum environment of a transmission electron microscope during current in-situ transmission electron microscope detection, the present invention proposes a sample rod system for an in-situ freezing and temperature-changing environment transmission electron microscope, the system comprising an airtight micro sample stage for manufacturing a liquid environment under high vacuum, a variable temperature metal heat conducting wire for manufacturing the temperature of liquid helium and liquid nitrogen, a liquid / gas conduit for manufacturing a required gas or liquid detection environment, and a Dewar tank for storing liquid helium and liquid nitrogen; the system of the present invention can be applied to real-time transmission electron microscope detection of chemical reactions in an in-situ freezing and temperature-changing environment.

[0006] The technical solution adopted by the present invention to solve the technical problem is:

[0007] A sample rod system for an in-situ freezing variable temperature environment transmission electron microscope, comprising a sample rod body 1, a dewar tank 2, a variable temperature metal heat conducting wire 3, a liquid / gas conduit 4, a metal wire 5, an electrodeless chip Ⅰ 7, and a cover plate 8;

[0008] The sample rod body 1 is a hollow structure along the axial direction, and the two ends of the sample rod body 1 are end A and end B. The end A of the sample rod body 1 is a sample stage 6. The sample stage 6 is provided with a sample groove with a conical structure. The cone vertex of the sample groove is close to the back of the sample stage 6. The open end of the sample groove faces the front of the sample stage 6. The front of the sample stage 6 is located directly below the lens of the transmission electron microscope. A sealing ring Ⅰ9 is provided on the side wall of the open end of the sample groove. A rectangular groove is provided on the outer side of the open end of the sample groove. A micro through hole connected to the sample groove is provided on the outer edge of the rectangular groove. The electrodeless chip Ⅰ7 is arranged on the upper side of the open end of the sample groove. The electrodeless chip I7 is square and located in the rectangular groove, the micro through hole is located on the side of the electrodeless chip I7, the periphery of the rectangular groove is provided with an annular groove cocentric with the sample groove, a sealing ring II is provided in the annular groove, the electrodeless chip I7 is located in the middle of the annular groove, the top of the electrodeless chip I7 is provided with an electrodeless chip II10, and the cover plate 8 is provided on the top of the electrodeless chip II10; a silicon nitride window I is provided in the middle of the electrodeless chip I7, a silicon nitride window II corresponding to the silicon nitride window I is provided in the middle of the electrodeless chip II10, and the silicon nitride window I and the silicon nitride window II are both located directly above the opening end of the sample groove;

[0009] The sample slot of the sample stage 6, the sealing ring I 9, the sealing ring II and the cover plate 8 form an airtight liquid environment chamber;

[0010] The variable temperature metal heat conductive wire 3 passes through the hollow structure of the sample rod body 1 and is located on the central axis of the sample rod body 1. One end of the variable temperature metal heat conductive wire 3 extends into the sample slot to contact the sample to be detected, and the other end of the variable temperature metal heat conductive wire 3 extends into the Dewar tank 2 to contact the freezing liquid in the Dewar tank 2; the liquid / gas conduit 4 passes through the hollow structure of the sample rod body 1 and is arranged along the inner side wall of the hollow structure of the sample rod body 1, one end of the liquid / gas conduit 4 extends into the sample slot, and one end of the liquid / gas conduit 4 is externally connected to a working liquid device or a working gas device.

[0011] In the system, the electrodeless chip II 10 is replaced by an electrochemical chip 11 or a heating chip 12, a silicon nitride window III corresponding to the silicon nitride window I of the electrodeless chip I7 is arranged in the middle of the electrochemical chip 11, and a silicon nitride window IV corresponding to the silicon nitride window I of the electrodeless chip I7 is arranged in the middle of the heating chip 12;

[0012] It also includes a metal wire 5, which passes through the hollow structure of the sample rod body 1 and is arranged along the inner wall of the hollow structure of the sample rod body 1. One end of the metal wire 5 is electrically connected to the electrochemical chip 11 or the heating chip 12. When the electrochemical chip 11 replaces the electrodeless chip II10, the other end of the metal wire 5 is externally connected to the electrochemical workstation; when the heating chip 12 replaces the electrodeless chip II10, the other end of the metal wire 5 is externally connected to the temperature controller.

[0013] Preferably, the substrate of the electrodeless chip I7 and the electrodeless chip II10 is a silicon substrate.

[0014] The substrate of the electrochemical chip 11 is a silicon substrate, the electrochemical positive and negative electrodes are embedded in the silicon substrate and located on the outside of the silicon nitride window III, and the electrochemical positive and negative electrodes are externally connected to the electrochemical workstation through the metal wire 5; when the test sample is subjected to electrochemical detection, the test sample flows into the gap between the electrodeless chip I7 and the electrochemical chip 11 through the micro-through holes on the outer edge of the rectangular groove, and the test sample contacts the electrochemical positive and negative electrodes embedded in the silicon substrate to form an electrochemical detection system.

[0015] Preferably, the electrochemical chip 11 applies a bias voltage in a range of ≤±12V and a current of ≤1A.

[0016] The substrate of the heating chip 12 is a silicon substrate, a heating resistor is embedded in the silicon substrate and is located outside the silicon nitride window IV, and the heating resistor is externally connected to a temperature controller via a metal wire 5 .

[0017] Only the Dewar 2 is used to realize in-situ freezing of the sample to be tested at the temperature of liquid nitrogen or liquid helium.

[0018] By combining the Dewar 2 with the heating chip 12, precise temperature control from liquid nitrogen temperature or liquid helium temperature to 1200°C can be achieved; preferably, the maximum heating rate is ≥20°C / second, and the maximum cooling rate is ≥500°C / second.

[0019] Preferably, the liquid flow rate in the liquid / gas conduit 4 is ≤150 mL / min, and the gas flow rate is ≤150 mL / min.

[0020] Preferably, the sample rod body 1 and the sample stage 6 are made of titanium alloy or other materials to avoid corrosion of the sample rod by liquid and gas environments and prevent potential safety hazards.

[0021] Beneficial effects of the present invention:

[0022] (1) The present invention uses a variable temperature metal heat conducting wire to transfer the temperature of the liquid helium or liquid nitrogen in the Dewar tank to the sample to be tested in the airtight micro-sample stage by heat conduction, thereby achieving in-situ freezing; the working liquid or working gas in the working liquid device or the working gas device is transported to the airtight micro-sample stage through a liquid / gas conduit, so that the sample maintains the required gas or liquid detection environment;

[0023] (2) The present invention uses a combination of a dewar tank and a heating chip to achieve temperature control from liquid nitrogen temperature or liquid helium temperature to 1200°C, and to achieve transmission electron microscopy detection of the sample to be tested under chemical reaction conditions at different temperatures;

[0024] (3) The present invention uses an electrochemical chip to replace the electrodeless chip II, which can perform electrochemical reaction tests on the test sample, detect the voltage and current signals of the sample, and simultaneously realize transmission electron microscopy detection of the test sample during the electrochemical reaction. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is a schematic diagram of the structure of a sample holder system for an in-situ cryo-temperature-variable environment transmission electron microscope;

[0026] Figure 2 Schematic diagram of assembling parts for the sample stage;

[0027] Figure 3 This is a schematic diagram of the structure after the sample stage is assembled;

[0028] Figure 4 Schematic diagram of the electrochemical chip structure;

[0029] Figure 5 This is a schematic diagram of the heating chip structure;

[0030] Figure 6 This is a schematic diagram of the Dewar tank structure;

[0031] In the figure, 1-sample rod body, 2-Dewar tank, 3-variable temperature metal heat conducting wire, 4-liquid / gas conduit, 5-metal wire, 6-sample stage, 7-electrodeless chip I, 8-cover plate, 9-sealing ring I, 10-electrodeless chip II, 11-electrochemical chip, 12-heating chip;

[0032] Figure 7 The morphology of platinum-nickel nanowires at different freezing temperatures in Example 1;

[0033] Figure 8 The dissolution diagram of nickel sulfide powder at different electrochemical reaction times in Example 2;

[0034] Fig. 9 These are morphology diagrams of the all-inorganic perovskite quantum dot materials at different temperatures in Example 3. DETAILED DESCRIPTION

[0035] The present invention will be further described below in conjunction with specific implementation modes.

[0036] Summary of the Invention

[0037] like Figures 1 to 6 As shown, a sample holder system for an in-situ freezing variable temperature environment transmission electron microscope comprises a sample holder body 1, a dewar tank 2, a variable temperature metal heat conducting wire 3, a liquid / gas conduit 4, a metal wire 5, an electrodeless chip Ⅰ 7, and a cover plate 8;

[0038] The sample rod body 1 is a hollow structure along the axial direction, and the two ends of the sample rod body 1 are end A and end B. The end A of the sample rod body 1 is a sample stage 6. The sample stage 6 is provided with a sample groove with a conical structure. The cone vertex of the sample groove is close to the back of the sample stage 6. The open end of the sample groove faces the front of the sample stage 6. The front of the sample stage 6 is located directly below the lens of the transmission electron microscope. A sealing ring Ⅰ9 is provided on the side wall of the open end of the sample groove. A rectangular groove is provided on the outer side of the open end of the sample groove. A micro through hole connected to the sample groove is provided on the outer edge of the rectangular groove. The electrodeless chip Ⅰ7 is arranged on the upper side of the open end of the sample groove. The electrodeless chip I7 is square and located in the rectangular groove, the micro through hole is located on the side of the electrodeless chip I7, the periphery of the rectangular groove is provided with an annular groove cocentric with the sample groove, a sealing ring II is provided in the annular groove, the electrodeless chip I7 is located in the middle of the annular groove, the top of the electrodeless chip I7 is provided with an electrodeless chip II10, and the cover plate 8 is provided on the top of the electrodeless chip II10; a silicon nitride window I is provided in the middle of the electrodeless chip I7, a silicon nitride window II corresponding to the silicon nitride window I is provided in the middle of the electrodeless chip II10, and the silicon nitride window I and the silicon nitride window II are both located directly above the opening end of the sample groove;

[0039] The sample slot of the sample stage 6, the sealing ring I 9, the sealing ring II and the cover plate 8 form an airtight liquid environment chamber;

[0040] The variable temperature metal heat conductive wire 3 passes through the hollow structure of the sample rod body 1 and is located on the central axis of the sample rod body 1. One end of the variable temperature metal heat conductive wire 3 extends into the sample slot to contact the sample to be detected, and the other end of the variable temperature metal heat conductive wire 3 extends into the Dewar tank 2 to contact the freezing liquid in the Dewar tank 2; the liquid / gas conduit 4 passes through the hollow structure of the sample rod body 1 and is arranged along the inner side wall of the hollow structure of the sample rod body 1, one end of the liquid / gas conduit 4 extends into the sample slot, and one end of the liquid / gas conduit 4 is externally connected to a working liquid device or a working gas device.

[0041] In the system, the electrodeless chip II 10 is replaced by an electrochemical chip 11 or a heating chip 12, a silicon nitride window III corresponding to the silicon nitride window I of the electrodeless chip I7 is arranged in the middle of the electrochemical chip 11, and a silicon nitride window IV corresponding to the silicon nitride window I of the electrodeless chip I7 is arranged in the middle of the heating chip 12;

[0042] It also includes a metal wire 5, which passes through the hollow structure of the sample rod body 1 and is arranged along the inner wall of the hollow structure of the sample rod body 1. One end of the metal wire 5 is electrically connected to the electrochemical chip 11 or the heating chip 12. When the electrochemical chip 11 replaces the electrodeless chip II10, the other end of the metal wire 5 is externally connected to the electrochemical workstation; when the heating chip 12 replaces the electrodeless chip II10, the other end of the metal wire 5 is externally connected to the temperature controller.

[0043] Preferably, the substrate of the electrodeless chip I7 and the electrodeless chip II10 is a silicon substrate.

[0044] The substrate of the electrochemical chip 11 is a silicon substrate, the electrochemical positive and negative electrodes are embedded in the silicon substrate and located on the outside of the silicon nitride window III, and the electrochemical positive and negative electrodes are externally connected to the electrochemical workstation through the metal wire 5; when the test sample is subjected to electrochemical detection, the test sample flows into the gap between the electrodeless chip I7 and the electrochemical chip 11 through the micro-through holes on the outer edge of the rectangular groove, and the test sample contacts the electrochemical positive and negative electrodes embedded in the silicon substrate to form an electrochemical detection system.

[0045] Preferably, the electrochemical chip 11 applies a bias voltage in a range of ≤±12V and a current of ≤1A.

[0046] The substrate of the heating chip 12 is a silicon substrate, a heating resistor is embedded in the silicon substrate and is located outside the silicon nitride window IV, and the heating resistor is externally connected to a temperature controller via a metal wire 5 .

[0047] Only the Dewar 2 is used to realize in-situ freezing of the sample to be tested at the temperature of liquid nitrogen or liquid helium.

[0048] By combining the Dewar 2 with the heating chip 12, precise temperature control from liquid nitrogen temperature or liquid helium temperature to 1200°C can be achieved; preferably, the maximum heating rate is ≥20°C / second, and the maximum cooling rate is ≥500°C / second.

[0049] The temperature precise control method:

[0050] S1. According to the relationship between the resistance value and temperature of the heating resistor in the heating chip 12, a resistance value and temperature relationship curve is established, the same voltage is applied, and the temperature is monitored in real time by monitoring the change in resistance value in real time;

[0051] S2. When the temperature of the sample to be tested does not reach the preset temperature, the temperature controller increases the current passing through the heating resistor by controlling the voltage across the heating resistor, thereby increasing the temperature of the heating resistor and the heat transferred to the sample to be tested, thereby achieving a temperature increase of the sample to be tested;

[0052] S3. When the temperature of the sample to be tested is higher than the preset temperature, the temperature controller reduces the current passing through the heating resistor by controlling the voltage across the heating resistor, thereby reducing the temperature of the heating resistor and the heat transferred to the sample to be tested, thereby cooling the sample to be tested.

[0053] Preferably, the liquid flow rate in the liquid / gas conduit 4 is ≤150 mL / min, and the gas flow rate is ≤150 mL / min.

[0054] Preferably, the sample rod body 1 and the sample stage 6 are made of titanium alloy or other materials to avoid corrosion of the sample rod by liquid and gas environments and prevent potential safety hazards.

[0055] Example 1: In-situ freezing is performed using an in-situ freezing variable temperature environment transmission electron microscope sample holder system, and the transmission image of the in-situ frozen test sample is detected in real time by the transmission electron microscope;

[0056] S1. The platinum-nickel nanowire sample to be tested is sealed in an airtight liquid environment chamber;

[0057] S2. The potassium hydroxide solution is introduced into the airtight liquid environment chamber through the liquid / gas conduit 4;

[0058] S3. The temperature of the liquid helium in the Dewar tank is transferred to the platinum-nickel nanowires of the test sample in the airtight micro-sample stage by heat conduction through a variable temperature metal heat conducting wire, thereby achieving in-situ freezing;

[0059] S4. Through in-situ freezing technology, the radiation damage caused by the electron beam of the transmission electron microscope to the sample can be reduced, and the morphology of the sample itself can be restored more realistically; it can be seen that the morphology of the platinum nickel nanowires is very regular, and the length can reach about 1um; as the temperature continues to decrease, it can be seen that part of the solution begins to freeze and crystallize. Figure 7.

[0060] Example 2: Using an in-situ frozen variable temperature environment transmission electron microscope with a sample rod system to perform an electrochemical reaction micro-reaction, and using a transmission electron microscope to detect the transmission image of the test sample of the electrochemical reaction in real time;

[0061] S1. The nickel sulfide powder to be tested is sealed in an airtight liquid environment chamber;

[0062] S2. Use electrochemical chip to replace electrodeless chip II10;

[0063] S3. The potassium hydroxide solution is introduced into the airtight liquid environment chamber through the liquid / gas conduit 4;

[0064] S4. Connect the metal wire 5 to the external electrochemical workstation and turn on the power supply;

[0065] S5. Real-time observation of electrochemical reactions in transmission electron microscopy;

[0066] S6. When the power is turned on, the electrochemical chip starts to work. It can be clearly seen that part of the nickel sulfide powder begins to dissolve, and the morphology of other undissolved powders also changes significantly, accompanied by a small amount of bubbles. Figure 8 .

[0067] Example 3: Using an in-situ freezing temperature-variable environment transmission electron microscope with a sample rod system to carry out chemical reactions at different temperatures, and using a transmission electron microscope to detect in real time the transmission images of the test sample of the chemical reactions at different temperatures;

[0068] S1. Seal the all-inorganic perovskite quantum dot material to be tested in an airtight liquid environment chamber;

[0069] S2. Replace the electrodeless chip II10 with a heating chip;

[0070] S3. The temperature of the chemical reaction is controlled at 25°C, 250°C, and 400°C, respectively, and the transmission electron microscope is used to detect the transmission image of the test sample of the chemical reaction at different temperatures in real time;

[0071] S4. When the temperature is 25℃, it can be seen that the morphology of the all-inorganic perovskite quantum dot material has no obvious change and still maintains a relatively regular square; when the temperature gradually rises to 250℃, it can be seen that part of the all-inorganic perovskite quantum dot material has fallen off and the contrast gradually turns white; when the temperature reaches 400℃, the contrast of almost the entire material has changed significantly. This is because the high temperature causes the all-inorganic perovskite quantum dot material to sublimate. Fig. 9 .

[0072] The specific embodiments of the present invention are described in detail above in conjunction with the accompanying drawings, but the present invention is not limited to the above embodiments. Various changes can be made within the knowledge scope of ordinary technicians in this field without departing from the purpose of the present invention.

Claims

1. A sample holder system for an in-situ freezing temperature-variable environment transmission electron microscope, characterized in that: It comprises a sample rod body (1), a Dewar tank (2), a variable temperature metal heat conducting wire (3), a liquid / gas conduit (4), a metal wire (5), an electrodeless chip I (7), and a cover plate (8); The sample rod body (1) is a hollow structure along the axial direction, the two ends of the sample rod body (1) are end A and end B, the end A of the sample rod body (1) is a sample stage (6), the sample stage (6) is provided with a sample groove with a conical structure, the cone vertex of the sample groove is close to the back of the sample stage (6), the open end of the sample groove faces the front of the sample stage (6), the front of the sample stage (6) is located directly below the lens of the transmission electron microscope, a sealing ring I (9) is provided on the side wall of the open end of the sample groove, a rectangular groove is provided on the outer side of the open end of the sample groove, a micro through hole connected to the sample groove is provided on the outer edge of the rectangular groove, and an electrodeless chip I (7) is arranged at the open end of the sample groove. The electrodeless chip I (7) is located above the electrodeless chip and in the rectangular groove, the micro-through hole is located on the side of the electrodeless chip I (7), the periphery of the rectangular groove is provided with an annular groove cocentric with the sample groove, a sealing ring II is provided in the annular groove, the electrodeless chip I (7) is located in the middle of the annular groove, the top of the electrodeless chip I (7) is provided with an electrodeless chip II (10), and the cover plate (8) is provided at the top of the electrodeless chip II (10); a silicon nitride window I is provided in the middle of the electrodeless chip I (7), a silicon nitride window II corresponding to the silicon nitride window I is provided in the middle of the electrodeless chip II (10), and both the silicon nitride window I and the silicon nitride window II are located directly above the opening end of the sample groove; The sample slot of the sample stage (6), the sealing ring I (9), the sealing ring II and the cover plate (8) form an airtight liquid environment chamber; The variable temperature metal heat conductive wire (3) passes through the hollow structure of the sample rod body (1) and is located on the central axis of the sample rod body (1); one end of the variable temperature metal heat conductive wire (3) extends into the sample slot to contact the sample to be detected, and the other end of the variable temperature metal heat conductive wire (3) extends into the Dewar tank (2) to contact the freezing liquid in the Dewar tank (2); the liquid / gas conduit (4) passes through the hollow structure of the sample rod body (1) and is arranged along the inner side wall of the hollow structure of the sample rod body (1); one end of the liquid / gas conduit (4) extends into the sample slot, and one end of the liquid / gas conduit (4) is externally connected to a working liquid device or a working gas device.

2. The sample holder system for an in-situ freezing temperature-variable environment transmission electron microscope according to claim 1, characterized in that: The electrodeless chip II (10) is replaced by an electrochemical chip (11) or a heating chip (12), wherein a silicon nitride window III corresponding to the silicon nitride window I of the electrodeless chip I (7) is arranged in the middle of the electrochemical chip (11), and a silicon nitride window IV corresponding to the silicon nitride window I of the electrodeless chip I (7) is arranged in the middle of the heating chip (12); The invention also comprises a metal wire (5), the metal wire (5) passes through the hollow structure of the sample rod body (1) and is arranged along the inner side wall of the hollow structure of the sample rod body (1), one end of the metal wire (5) is electrically connected to the electrochemical chip (11) or the heating chip (12), and when the electrochemical chip (11) replaces the electrodeless chip II (10), the other end of the metal wire (5) is externally connected to the electrochemical workstation; when the heating chip (12) replaces the electrodeless chip II (10), the other end of the metal wire (5) is externally connected to the temperature controller.

3. The sample holder system for an in-situ freezing temperature-variable environment transmission electron microscope according to claim 1, characterized in that: The substrates of the electrodeless chip I (7) and the electrodeless chip II (10) are silicon substrates.

4. The sample holder system for an in-situ freezing temperature-variable environment transmission electron microscope according to claim 2, characterized in that: The substrate of the electrochemical chip (11) is a silicon substrate, the electrochemical positive and negative electrodes are embedded in the silicon substrate and located outside the silicon nitride window III, and the electrochemical positive and negative electrodes are externally connected to an electrochemical workstation through metal wires (5); when the test sample is subjected to electrochemical detection, the test sample flows into the gap between the electrodeless chip I (7) and the electrochemical chip (11) through the micro-through holes on the outer edge of the rectangular groove, and the test sample contacts the electrochemical positive and negative electrodes embedded in the silicon substrate to form an electrochemical detection system.

5. The sample holder system for an in-situ freezing temperature-variable environment transmission electron microscope according to claim 2, characterized in that: The substrate of the heating chip (12) is a silicon substrate, the heating resistor is embedded in the silicon substrate and is located outside the silicon nitride window IV, and the heating resistor is externally connected to a temperature controller via a metal wire (5).

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