A laser-heated reaction cell and method of use thereof

Abstract

The application provides a laser heating reaction cell and a use method thereof, and relates to the field of surface catalysis. The laser heating reaction cell comprises a reaction cell, a laser heating mechanism and an infrared detection mechanism. A laser window, a temperature measurement window and a double-sided flange are arranged on the side wall of the reaction cell. An observation window or a thermocouple feedthrough is arranged in the double-sided flange. A sample loading mechanism suitable for placing a sample is further arranged in the inner cavity of the reaction cell. The sample loading mechanism is connected with the double-sided flange. The laser heating mechanism is located outside the reaction cell. The infrared detection mechanism is located outside the reaction cell. The application further comprises an air inlet pipe and an air outlet pipe. The application can test small or medium active surface area catalysts through a small volume reaction cell, including activity test of single crystal and powder catalysts. The laser heating mechanism can realize rapid temperature rise and fall of the sample surface without contact and pollution. The air inlet pipe can directly spray gas on the sample surface, thereby increasing the contact efficiency with the sample.

Description

Technical Field

[0001] This invention relates to the field of surface catalysis, and in particular to a laser-heated reaction cell and its method of use. Background Technology

[0002] Catalysis is a core area in chemical science and industry. Surface catalysis research often uses precisely defined metal nanoparticles, either single crystals of metal or supported on single crystals of oxides, as model catalysts. Surface science methods have not only provided fundamental knowledge for understanding the structure of active sites and molecular-solid interface processes, but have also successfully advanced the exploration of industrially relevant catalytic effects. Based on vacuum technology, surface science benefits from a variety of powerful tools for characterizing the structure, physical, and chemical properties of solid surfaces. Diffraction techniques (such as LEED and SXRD), scanning probe microscopy (such as STM and AFM), electronic and ion spectroscopy (such as AES, XPS, and LEIS), vibrational spectroscopy (such as HREELS, IRAS, and SFG), and mass spectrometry (such as TDS and MBRS) are now widely used in catalytic surface science. With the assistance of these surface science techniques, the research methods for model catalysts provide a solid foundation for a deeper understanding of the atomic-scale mechanisms and kinetics of heterogeneous catalytic processes, and often reveal the correlation between the microstructure of materials and their catalytic performance. However, this research method is usually carried out under ultra-high vacuum (UHV) conditions, thus requiring the overcoming of the gap between the “clean” UHV conditions required by surface science tools and the high-pressure conditions required for industrial catalytic testing. Summary of the Invention

[0003] To address the aforementioned problems, this invention provides a laser-heated reaction cell that enables activity testing of catalysts with small or medium active surface areas, including single-crystal and powdered catalysts, using a small-volume reaction cell.

[0004] The present invention provides a laser-heated reaction cell, comprising a reaction cell, a laser heating mechanism, and an infrared detection mechanism; the side wall of the reaction cell is provided with a laser viewing window, a temperature measuring window, and a double-sided flange, the double-sided flange being provided with an observation window or thermocouple feedthrough; the inner cavity of the reaction cell is also provided with a sample loading mechanism suitable for placing samples, the sample loading mechanism being connected to the double-sided flange; the laser heating mechanism is located outside the reaction cell, and the laser emitted by the laser heating mechanism passes through the laser viewing window and hits the sample surface; the infrared detection mechanism is located outside the reaction cell, and the infrared light emitted by the infrared detection mechanism passes through the temperature measuring window and hits the sample surface; it also includes an inlet pipe and an outlet pipe, one end of the inlet pipe passing through the side wall of the reaction cell and extending towards the sample surface, the other end being connected to an external inlet device; one end of the outlet pipe is connected to the inner cavity of the reaction cell, the other end being connected to a chromatograph or mass spectrometer.

[0005] In one feasible embodiment of the present invention, the sample loading mechanism includes a sample fork-shaped seat and a sample holder, the sample fork-shaped seat having an assembly groove, and the sample holder and the assembly groove being detachably connected; the sample holder also has a sample groove suitable for placing a sample.

[0006] In one feasible embodiment of the present invention, the side wall of the reaction tank is further provided with a connecting hole, the connecting hole being adapted to connect to an external pre-vacuum system, and a valve body for closing the connecting hole is also provided in the connecting hole.

[0007] In one feasible embodiment of the present invention, a water-cooling passage is provided in the side wall of the reaction tank, and a water-cooling inlet pipe and a water-cooling outlet pipe are respectively provided at both ends of the water-cooling passage, and both the water-cooling inlet pipe and the water-cooling outlet pipe are externally connected to a pump body.

[0008] In one feasible embodiment of the present invention, a vacuum gauge is also provided on the side wall of the reaction tank, and the detection end of the vacuum gauge is located in the inner cavity of the reaction tank.

[0009] In one feasible embodiment of the present invention, the reaction cell is rectangular in shape and the eight vertices of the rectangle are beveled surfaces; the air inlet pipe passes through the reaction cell from one of the beveled surfaces and extends toward the sample surface; the water-cooled liquid inlet pipe and the water-cooled liquid outlet pipe respectively pass through the side walls of the reaction cell from two opposite beveled surfaces; the laser viewing window and the temperature measuring window are respectively located on two opposite side walls of the reaction cell; the vacuum gauge and the air outlet pipe are respectively located on two opposite side walls of the reaction cell; and the double-sided flange and the connecting hole are respectively located on two opposite side walls of the reaction cell.

[0010] In one feasible embodiment of the present invention, a thermocouple feedthrough is provided in the double-sided flange; a first gasket is also provided on the sample holder, the first gasket being adapted to wind a thermocouple, and the thermocouple passing through the thermocouple feedthrough through the side wall of the reaction cell.

[0011] In one feasible embodiment of the present invention, the first gasket is further provided with a second gasket and a third gasket. The second gasket and the third gasket are both arranged perpendicularly to the first gasket and are both suitable for winding a thermocouple. The second gasket and the third gasket pass through the side wall of the reaction tank through the thermocouple feedthrough.

[0012] In one feasible embodiment of the present invention, the laser heating mechanism includes a laser adjustment mechanism and a laser heater disposed on the laser adjustment mechanism, the laser adjustment mechanism being connected to the side wall of the reaction tank via a bracket; the infrared detection mechanism includes an infrared adjustment mechanism and an infrared emitter disposed on the infrared adjustment mechanism, the infrared adjustment mechanism being connected to the side wall of the reaction tank via a bracket.

[0013] The present invention also provides a method for using a laser-heated reaction cell, comprising the following steps:

[0014] Step 1) Mount the sample onto the sample loading mechanism;

[0015] Step 2) Start the laser heating mechanism to heat the sample and use the infrared detection mechanism to detect the temperature in real time;

[0016] Step 3) Gas is introduced through the air inlet pipe and sprayed directly onto the sample surface to react with the sample;

[0017] Step 4) The gas reacted with the sample enters the chromatograph or mass spectrometer through the gas outlet tube and is detected by the chromatograph or mass spectrometer.

[0018] The laser-heated reaction cell provided by this invention has the following beneficial effects:

[0019] 1. This invention enables the testing of catalysts with small or medium active surface areas, including single crystal and powder catalysts, using a small-volume reaction cell; and by using laser heating, rapid temperature rise and fall of samples can be achieved without contact or contamination, while the gas inlet pipe can directly spray gas onto the sample surface, increasing the contact efficiency with the sample.

[0020] 2. The water-cooled inlet pipe, water-cooled passage, and water-cooled outlet pipe in this invention can be loaded with cooling liquid, which can effectively avoid side reactions caused by the temperature rise of the inner wall of the reaction cell under the high temperature of the sample surface.

[0021] 3. The connecting hole in this invention can be connected to the pre-vacuum system to complete the cleaning and characterization of the sample without contact with air.

[0022] 4. This invention can pretreat samples at different temperatures, pressures, times, and atmospheres, and then combine them with other vacuum methods for characterization. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the overall structure of the present invention.

[0024] Figure 2 This is a schematic diagram of the reaction cell and laser window in this invention.

[0025] Figure 3 This is a schematic diagram of the reaction tank and temperature measurement window in this invention.

[0026] Figure 4 This is a schematic diagram of the sample loading mechanism in this invention.

[0027] Figure 5 This is a schematic diagram of the sample fork-shaped seat in this invention.

[0028] Figure 6 This is a schematic diagram of the sample tray structure in this invention.

[0029] Figure 7 This is a schematic diagram of the structure of the observation window in this invention.

[0030] Figure Labels

[0031] Reaction tank 1

[0032] Laser Window 11

[0033] Temperature measurement window 12

[0034] Double-sided flange 13

[0035] View window 13.1

[0036] Thermocouple feedthrough 13.2

[0037] Intake pipe 14

[0038] 15 air outlet pipe

[0039] Connecting hole 16

[0040] Water-cooled inlet pipe 17

[0041] Water-cooled outlet pipe 18

[0042] Vacuum gauge 19

[0043] Laser heating mechanism 2

[0044] Laser adjustment mechanism 21

[0045] Laser heater 22

[0046] Infrared detection agency 3

[0047] Infrared adjustment mechanism 31

[0048] Infrared emitter 32

[0049] Sample loading mechanism 4

[0050] Sample fork holder 41

[0051] Assembly groove 41.1

[0052] Adapter board 41.2

[0053] Fork plate 41.3

[0054] Clamping block 41.4

[0055] Sample tray 42

[0056] Sample groove 42.1

[0057] First gasket 42.2

[0058] Second gasket 42.3

[0059] Third gasket 42.4 Detailed Implementation

[0060] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. In the description of the present invention, it should be noted that the terms "left side", "right side", "upper side", "lower side", "above", "below", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention. In addition, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0061] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0062] Furthermore, in the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0063] This invention provides a laser-heated reaction cell, see below. Figure 1 The reaction tank includes a reaction vessel 1, a laser heating mechanism 2, and an infrared detection mechanism 3. The reaction vessel 1 is typically a small reaction vessel with a volume of 150–250 mL, preferably 200 mL, and is preferably made of Inconel 1625 stainless steel. The side wall of the reaction vessel 1 is provided with a laser viewing window 11, a temperature measuring window 12, and a double-sided flange 13. The double-sided flange 13 is provided with an observation window 13.1 or a thermocouple feedthrough 13.2. (See reference...) Figure 5 and Figure 7 , Figure 5 Thermocouple feedthrough 13.2 is installed in the middle. Figure 7A viewing window 13.1 is provided for observing the conditions inside the reaction cell 1. In experiments where thermocouples are not used, viewing window 13.1 can be provided for convenient observation. Viewing window 13.1 is typically a high-pressure window. The double-sided flange 13 usually also has a flange plate to support viewing window 13.1. The material of viewing window 13.1 is preferably boron nitride. A thermocouple feedthrough 13.2 is used to lead the thermocouple out of the reaction cell 1. Therefore, in experiments where thermocouples are used to calibrate sample emissivity or measure sample surface temperature, a thermocouple feedthrough 13.2 is provided in the double-sided flange 13. In short, one of viewing window 13.1 and thermocouple feedthrough 13.2 is chosen; they will not coexist. The double-sided flange 13 can be of model CF35-CF16. (See reference...) Figure 4 The reaction tank 1 is further equipped with a sample loading mechanism 4 suitable for placing samples, which is connected to the double-sided flange 13. (Continue reading) Figure 1 The laser heating mechanism 2 is located outside the reaction tank 1. The laser emitted by the laser heating mechanism 2 passes through the laser window 11 and strikes the sample surface. The infrared detection mechanism 3 is also located outside the reaction tank 1. The infrared light emitted by the infrared detection mechanism 3 passes through the temperature measuring window 12 and strikes the sample surface. The laser heating mechanism 2 heats the sample surface by emitting laser light, while the infrared detection mechanism 3 detects the sample surface temperature by using infrared light. The materials of the laser window 11 and the temperature measuring window 12 are typically quartz glass. (Continue reading...) Figure 1 It also includes an inlet pipe 14 and an outlet pipe 15. One end of the inlet pipe 14 passes through the side wall of the reaction cell 1 and extends towards the sample surface. This port is usually close to the sample surface so that the gas can be sprayed directly onto the sample surface to accelerate the reaction rate of the sample. The other end of the inlet pipe 14 is connected to an external gas inlet device. This port can also be connected to a multi-port adapter so that the inlet pipe 14 can be connected to multiple gas inlet devices, thereby allowing the inlet pipe 14 to introduce different gases into the inner cavity of the reaction cell 1. Generally speaking, the inlet pipe 14 should be able to introduce three different gas paths. When the gas is introduced, the inlet pipe 14 will increase the pressure in the inner cavity of the reaction cell 1, making the inner cavity of the reaction cell 1 a high-pressure environment. One end of the outlet pipe 15 is connected to the inner cavity of the reaction cell 1, and the other end is connected to a chromatograph or mass spectrometer. This invention enables the testing of catalysts with small or medium active surface areas, including single crystal and powder catalysts, using a small-volume reaction cell; and by using laser heating, the sample surface temperature can be rapidly increased or decreased without contact or contamination, while the gas inlet pipe can directly spray gas onto the sample surface, increasing the contact efficiency with the sample.

[0064] In the laser-heated reaction tank provided in the embodiments of the present invention, see... Figure 4 and 5The sample loading mechanism 4 includes a sample fork-shaped seat 41 and a sample holder 42. The sample fork-shaped seat 41 has an assembly groove 41.1. The sample holder 42 and the assembly groove 41.1 are detachably connected. The sample holder 42 also has a sample groove 42.1 suitable for placing samples. Further, the sample fork-shaped seat 41 includes a transition plate 41.2 and two fork plates 41.3 connected to the transition plate 41.2. The two fork plates 41.3 are arranged parallel to each other, with sufficient space between them to prevent obstruction of the sample. Each fork plate 41.3 has an assembly groove 41.1. The two sides of the sample holder 42 are respectively inserted into the assembly grooves 41.1 of the two fork plates 41.3 to complete the assembly. In a specific embodiment, see [reference needed]. Figure 4 One end of the sample holder 42 is also provided with a clamping block 41.4 that can cooperate with the vacuum transfer rod. Generally speaking, when assembling the sample holder 42 and the sample fork seat 41, the vacuum transfer rod can directly insert the sample holder 42 into the assembly groove 41.1 in the sample fork seat 41. As a supplementary note, the sample fork seat 41 and the sample holder 42 are preferably made of boron nitride.

[0065] In the laser-heated reaction tank provided in the embodiments of the present invention, see... Figure 1 and Figure 2 The reaction tank 1 also has a connecting hole 16 on its side wall. The connecting hole 16 is suitable for connecting to an external pre-vacuum system, and a valve body for closing the connecting hole 16 is also provided within it. For illustration, the pre-vacuum system typically includes a vacuum chamber and a vacuum pump for evacuation. Samples can be prepared, cleaned, and characterized within the pre-vacuum system to ensure initial sample cleanliness and a consistent surface condition. Alternatively, samples can be etched, annealed, and characterized within the pre-vacuum system to ensure the required initial state. Further, the valve body is preferably a gate valve. The connecting hole 16 in this invention can interface with the pre-vacuum system, allowing for sample cleaning and characterization without contact with air.

[0066] In the laser-heated reaction tank provided in the embodiments of the present invention, see... Figure 1 and Figure 2 The reaction tank 1 is further provided with a water-cooling passage in its side wall. A water-cooling inlet pipe 17 and a water-cooling outlet pipe 18 are respectively located at both ends of the water-cooling passage, and both the water-cooling inlet pipe 17 and the water-cooling outlet pipe 18 are externally connected to a pump body. For illustration, the water-cooling passage is typically evenly distributed throughout the side wall of the reaction tank 1 to ensure uniform cooling of the inner wall of the reaction tank 1. The cooled inner wall of the reaction tank 1 can effectively remove heat dissipated from the sample surface. The water-cooling inlet pipe 17, the water-cooling passage, and the water-cooling outlet pipe 18 in this invention can be filled with coolant, which can effectively avoid side reactions caused by the temperature rise of the inner wall of the reaction tank 1 under high sample surface temperature.

[0067] In the laser-heated reaction tank provided in the embodiments of the present invention, see... Figure 1 A vacuum gauge 19 is also provided on the side wall of the reaction tank 1, and the detection end of the vacuum gauge 19 is located in the inner cavity of the reaction tank 1. For reference, the vacuum gauge 19 is used to read the gas pressure in the inner cavity of the reaction tank 1, so as to facilitate the experimenter to monitor the gas pressure in the inner cavity of the reaction tank 1.

[0068] In the laser-heated reaction tank provided in the embodiments of the present invention, see... Figure 2 and Figure 3 The reaction cell 1 is rectangular in shape, with its eight vertices being beveled. The air inlet pipe 14 passes through one of the beveled surfaces of the reaction cell 1 and extends towards the sample surface. The water-cooled liquid inlet pipe 17 and the water-cooled liquid outlet pipe 18 respectively enter the side wall of the reaction cell 1 from two opposite beveled surfaces. The laser viewing window 11 and the temperature measuring window 12 are located on two opposite side walls of the reaction cell 1, respectively. (See reference...) Figure 1 The vacuum gauge 19 and the vent pipe 15 are located on two opposite side walls of the reaction tank 1, and the double-sided flange 13 and the connecting hole 16 are located on two opposite side walls of the reaction tank 1.

[0069] In the laser-heated reaction tank provided in the embodiments of the present invention, see... Figure 4 The double-sided flange 13 is provided with a thermocouple feedthrough 13.2, and the sample holder 42 is also provided with a first gasket 42.2. The first gasket 42.2 is adapted to wind a thermocouple, and the thermocouple passes through the thermocouple feedthrough 13.2 and exits the side wall of the reaction cell 1. For illustration, the thermocouple is used to measure the surface temperature of the sample. The main difference between K-type thermocouple measurement and infrared temperature measurement by the infrared temperature measurement mechanism 3 is the temperature detection range. The temperature measurement range of the K-type thermocouple is -200 to 1300℃, while the temperature measurement range of the infrared temperature measurement mechanism 3 is 200 to 2000℃.

[0070] In the laser-heated reaction tank provided in the embodiments of the present invention, see... Figure 4 The first gasket 42.2 is further provided with a second gasket 42.3 and a third gasket 42.4. Both the second and third gaskets 42.3 and 42.4 are perpendicular to the first gasket 42.2 and are suitable for winding thermocouples. The second and third gaskets 42.3 and 42.4 extend out of the side wall of the reaction cell 1 through the thermocouple feedthrough 13.2. For illustrative purposes, whether only the first gasket 42.2 is provided or both the second and third gaskets 42.3 and 42.4 are provided, the gaskets generally do not obstruct the sample recess 42.1, ensuring that the sample is placed within the sample recess 42.1. Further, the materials of the first gasket 42.2, the second gasket 42.3, and the third gasket 42.4 are preferably boron carbide, and the thermocouples are preferably K-type thermocouples.

[0071] In the laser-heated reaction tank provided in the embodiments of the present invention, see... Figure 1 The laser heating mechanism 2 includes a laser adjustment mechanism 21 and a laser heater 22 disposed on the laser adjustment mechanism 21. The laser adjustment mechanism 21 is connected to the side wall of the reaction tank 1 via a bracket. The infrared detection mechanism 3 includes an infrared adjustment mechanism 31 and an infrared emitter 32 disposed on the infrared adjustment mechanism 31. The infrared adjustment mechanism 31 is connected to the side wall of the reaction tank 1 via a bracket. For illustration, the laser adjustment mechanism 21 can be ZJP-5M20, and the bracket is preferably made of Incone 1625 stainless steel.

[0072] The present invention also provides a method of using the laser-heated reaction cell as described in any one of claims 1 to 9, comprising the following steps:

[0073] Step 1) Install the sample on the sample loading mechanism 4; further, the sample is pre-installed in the sample groove 42.1 in the sample holder 42, and then the sample holder 42 is assembled into the assembly groove 41.1 of the sample fork seat 41 by the sample transfer rod.

[0074] Step 2) Start the laser heating mechanism 2 to heat the sample and perform real-time temperature detection through the infrared detection mechanism 3; further, the positions of the laser heater 22 and the infrared emitter 32 can be adjusted by the laser adjustment mechanism 21 and the infrared adjustment mechanism 31 respectively. The spot of the infrared beam emitted by the infrared emitter 32 is usually located at the center of the sample.

[0075] Step 3) Gas is introduced through the gas inlet pipe 14 and directly sprayed onto the sample surface to react with the sample; further, during the sample reaction, coolant can be introduced through the water-cooled liquid inlet pipe 17. The coolant flows in the water-cooling passage and reduces the temperature of the inner wall of the reaction tank 1, so as to achieve the effect of cooling the inner cavity of the reaction tank 1.

[0076] Step 4) The gas reacted with the sample enters the chromatograph or mass spectrometer through the gas outlet tube 15 and is detected by the chromatograph or mass spectrometer.

[0077] Before step 1), there may be a preliminary step, in which the sample is installed in the sample groove 42.1, and then the sample holder 42 is sent into the pre-vacuum system through the sample transfer rod to complete the preliminary processing of the sample. The preliminary processing may include sample preparation, cleaning, etching, annealing and characterization, etc. Then, the valve body is opened to connect the inner cavity of the reaction cell 1 with the pre-vacuum system, and the residual gas in the inner cavity of the reaction cell 1 is extracted by the vacuum pump in the pre-vacuum system. Then, the sample tray is sent into the inner cavity of the reaction cell 1 through the sample transfer rod, and the sample tray and the sample fork seat 41 are assembled.

[0078] Example 1

[0079] In a typical application, the sample is prepared, cleaned, and characterized using a pre-vacuum system to ensure initial sample cleanliness and consistent surface condition. The valve is opened to connect the reaction chamber 1 to the pre-vacuum system, and a vacuum pump connected to the pre-vacuum system removes residual gas from the reaction chamber 1, bringing the vacuum level in the reaction chamber close to that of the pre-vacuum system. Next, the sample holder 42 is grasped by the vacuum transfer rod and assembled with the sample fork seat 41. Then, the gate valve is closed to disconnect the connection between the reaction chamber 1 and the pre-vacuum system. Next, the water cooling mechanism is activated to ensure that the temperature of the inner wall of reaction cell 1 is kept below 20°C to eliminate the influence of background reaction. Then, the reaction gas corresponding to the components and pressure is introduced into the inner cavity of reaction cell 1 through the gas inlet pipe 14. Then, the laser heating mechanism 2 is turned on through the software, and the heating power is set to heat the sample. At the same time, the surface temperature of the sample is measured through the infrared detection mechanism 3 and the thermocouple. The thermocouple can also be used to calibrate the emissivity of the sample in advance. Finally, after the sample reaches the preset reaction time, the product is detected by the chromatography or mass spectrometry connected through the gas outlet pipe 15.

[0080] Example 2

[0081] In a typical application, the sample is etched, annealed, and characterized using a pre-vacuum system to ensure the required initial state. The valve is opened to connect the reaction chamber 1 to the pre-vacuum system. A vacuum pump connected to the pre-vacuum system then removes residual gas from the reaction chamber 1, bringing the vacuum level in the reaction chamber close to that of the pre-vacuum system. Next, the sample holder 42 is grasped by the vacuum transfer rod and assembled with the sample fork seat 41. The gate valve is then closed to disconnect the connection between the reaction chamber 1 and the pre-vacuum system. Finally, reaction gas is introduced through the inlet pipe 14 to pre-treat the sample under specific atmosphere and temperature. The sample is then controlled by a vacuum gauge 1. 9 can detect the pressure in the inner cavity of reaction cell 1, so that the experimenter can adjust the reaction gas introduced into the inlet pipe 14 in real time according to the pressure feedback from the vacuum gauge 19, thereby realizing atmospheres with different pressures from high vacuum to 1 bar; then, the valve body is opened to connect the inner cavity of reaction cell 1 to the pre-vacuum system and the pre-vacuum system and the inner cavity of reaction cell 1 are evacuated again, and then the sample holder 42 is transferred to the pre-vacuum system through the vacuum transfer rod, and then quasi-in-situ characterization is performed using vacuum characterization techniques such as XPS, AES, TPD and LEED, so as to obtain more detailed information about the structure and chemical properties of the catalyst active sites under actual reaction conditions.

[0082] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and substitutions can be made without departing from the technical principles of the present invention, and these improvements and substitutions should also be considered within the scope of protection of the present invention.

Claims

1. A laser-heated reaction cell, characterized in that: It includes a reaction cell (1), a laser heating mechanism (2), and an infrared detection mechanism (3); the side wall of the reaction cell (1) is provided with a laser viewing window (11), a temperature measuring window (12), and a double-sided flange (13), and the double-sided flange (13) is provided with an observation window (13.1) or a thermocouple feedthrough (13.2); the inner cavity of the reaction cell (1) is also provided with a sample loading mechanism (4) suitable for placing samples, and the sample loading mechanism (4) is connected to the double-sided flange (13); The laser heating mechanism (2) is located outside the reaction cell (1), and the laser emitted by the laser heating mechanism (2) passes through the laser window (11) and hits the sample surface; the infrared detection mechanism (3) is located outside the reaction cell (1), and the infrared light emitted by the infrared detection mechanism (3) passes through the temperature measuring window (12) and hits the sample surface; It also includes an inlet pipe (14) and an outlet pipe (15). One end of the inlet pipe (14) passes through the side wall of the reaction cell (1) and extends toward the sample surface, while the other end is connected to an inlet device. One end of the outlet pipe (15) is connected to the inner cavity of the reaction cell (1), while the other end is connected to a chromatogram or mass spectrometer.

2. The laser-heated reaction tank according to claim 1, characterized in that: The sample loading mechanism (4) includes a sample fork-shaped seat (41) and a sample holder (42). The sample fork-shaped seat (41) is provided with an assembly groove (41.1). The sample holder (42) and the assembly groove (41.1) are detachably connected. The sample holder (42) is also provided with a sample groove (42.1) suitable for placing samples.

3. The laser-heated reaction tank according to claim 1, characterized in that: The side wall of the reaction tank (1) is also provided with a connecting hole (16), which is suitable for connecting to an external pre-vacuum system. A valve body for closing the connecting hole (16) is also provided in the connecting hole (16).

4. The laser-heated reaction tank according to claim 2 or 3, characterized in that: The side wall of the reaction tank (1) is also provided with a water-cooled passage. The two ends of the water-cooled passage are respectively provided with a water-cooled inlet pipe (17) and a water-cooled outlet pipe (18). Both the water-cooled inlet pipe (17) and the water-cooled outlet pipe (18) are externally connected to a pump body.

5. The laser-heated reaction tank according to claim 4, characterized in that: A vacuum gauge (19) is also provided on the side wall of the reaction tank (1), and the detection end of the vacuum gauge (19) is located in the inner cavity of the reaction tank (1).

6. The laser-heated reaction tank according to claim 5, characterized in that: The reaction cell (1) is rectangular in shape and the eight vertices of the rectangle are beveled. The air inlet pipe (14) passes through the reaction cell (1) from one of the beveled surfaces and extends toward the sample surface. The water-cooled liquid inlet pipe (17) and the water-cooled liquid outlet pipe (18) pass into the side wall of the reaction cell (1) from two opposite beveled surfaces. The laser viewing window (11) and the temperature measuring window (12) are located on two opposite side walls of the reaction tank (1), the vacuum gauge (19) and the vent pipe (15) are located on two opposite side walls of the reaction tank (1), and the double-sided flange (13) and the connecting hole (16) are located on two opposite side walls of the reaction tank (1).

7. The laser-heated reaction tank according to claim 1, characterized in that: The double-sided flange (13) is provided with a thermocouple feed passage (13.2); the sample holder (42) is also provided with a first gasket (42.2), on which a thermocouple is suitable for winding, and the thermocouple passes through the thermocouple feed passage (13.2) to exit the side wall of the reaction cell (1).

8. The laser-heated reaction tank according to claim 7, characterized in that: The first gasket (42.2) is also provided with a second gasket (42.3) and a third gasket (42.4). The second gasket (42.3) and the third gasket (42.4) are both arranged perpendicularly to the first gasket (42.2) and are both suitable for winding thermocouples. The second gasket (42.3) and the third gasket (42.4) pass through the side wall of the reaction tank (1) through the thermocouple feed (13.2).

9. The laser-heated reaction tank according to claim 1, characterized in that: The laser heating mechanism (2) includes a laser adjustment mechanism (21) and a laser heater (22) disposed on the laser adjustment mechanism (21). The laser adjustment mechanism (21) is connected to the side wall of the reaction tank (1) through a bracket. The infrared detection mechanism (3) includes an infrared adjustment mechanism (31) and an infrared emitter (32) disposed on the infrared adjustment mechanism (31). The infrared adjustment mechanism (31) is connected to the side wall of the reaction tank (1) through a bracket.

10. A method of using a laser-heated reaction cell as described in any one of claims 1 to 9, comprising the following steps: Step 1) Mount the sample onto the sample loading mechanism (4); Step 2) Start the laser heating mechanism (2) to heat the sample and perform real-time temperature detection through the infrared detection mechanism (3); Step 3) Gas is introduced through the air inlet pipe (14), and the gas is directly sprayed onto the sample surface to react with the sample; Step 4) The gas after reacting with the sample enters the chromatograph or mass spectrometer through the gas outlet tube (15) and is detected by the chromatograph or mass spectrometer.

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