Composite temperature control system for near-atmospheric pressure X-ray photoelectron spectroscopy experimental station

Abstract

The present invention discloses a composite temperature control system for a near-atmospheric pressure X-ray photoelectron spectroscopy experimental station, which relates to the field of synchrotron radiation instrument design. The sample holder includes: a ZrO2 support, and a heating conductor, a ceramic heater, and a protective layer stacked from top to bottom; the sample rod includes: a laser emitting unit, whose light beam irradiates the bottom of the ZrO2 support, and heat is transferred from bottom to top through the protective layer, the ceramic heater, the heating conductor, and the sample holder to the sample; the closed end of the liquid cooling tube is wrapped around the hollow feed-through tube and adhered to the back of the rod head platform. The present invention avoids sample contamination through indirect laser heating, and improves thermal management efficiency through winding liquid cooling, achieving temperature control in a wide temperature range of 140K to 1500K. By stacking corrosion-resistant structures and charge extraction layers, data reliability under high temperature / atmosphere is guaranteed, and it is suitable for in-situ dynamic observation of catalytic reactions.

Description

Technical Field

[0001] The present invention relates to the field of synchrotron radiation instrument design, specifically a composite temperature control system for a near-atmospheric pressure X-ray photoelectron spectroscopy (NAP-XPS) experimental station. The system integrates a variable-temperature sample holder and sample rod to achieve dynamic temperature control over a wide temperature range (140K–1500K), corrosion resistance, and support for in-situ electrochemical testing. Background Art

[0002] Near-atmospheric pressure X-ray photoelectron spectroscopy (NAP-XPS) requires dynamic observation of the chemical evolution of a material's surface under conditions close to those of a real-world reaction (1-30 mbar), placing stringent demands on temperature control. Catalytic reactions often require high temperatures of 800-1200 K, exposing the sample to the reaction atmosphere (such as hydrogen and carbon monoxide) at temperatures close to actual operating conditions, allowing direct observation of the dynamic chemical state changes of surface elements. However, the maximum temperature of conventional resistive heating sample holders is typically below 800 K, making them difficult to meet the requirements of high-temperature catalysis. Furthermore, thermal hysteresis occurs during the heating process, making it difficult to capture transient reaction processes. Some materials are susceptible to thermal decomposition or surface reconstruction at high temperatures. For example, transition metal catalysts experience lattice reorganization above 1000 K, resulting in the loss of active sites. While gradient heating or constant temperature maintenance can distinguish between thermal effects and the influence of the reaction itself, traditional temperature control methods struggle to achieve rapid and precise responses.

[0003] In low-temperature research scenarios, liquid nitrogen cooling (down to 140K) effectively suppresses sample thermal motion, preventing thermal decomposition or volatilization caused by high temperatures. This is crucial for studying the adsorption behavior of gas molecules on material surfaces. However, existing cooling systems and heating modules are often designed separately, requiring sample disassembly during switching, disrupting the in-situ testing environment. Furthermore, laser heating achieves contactless energy transfer through the interaction of high-energy photons with matter. When a laser beam with a wavelength of 808-940nm illuminates the material surface, the photon energy is absorbed by electrons and converted into heat. While this technology offers the advantages of rapid temperature changes (140K to 1500K) in milliseconds and localized energy deposition, direct laser exposure to the sample can easily cause material volatilization and contaminate the testing environment. For example, organic catalysts exposed to direct laser light can produce carbon residues, interfering with XPS spectrum interpretation. Reflected laser light can also damage the sample holder's mechanical structure, resulting in reduced positioning accuracy.

[0004] Existing technologies have not yet effectively solved the problem of multi-physics field coupling. When conducting gas-solid interface reactions in near-normal pressure atmospheres (such as 25 mbar CO), the metal components of traditional sample holders are easily corroded, resulting in deterioration of resistance heating stability; the charge accumulated on the sample surface during electrochemical in-situ testing will interfere with the photoelectron signal, and conventional charge extraction schemes use metal covering layers, which may introduce contamination or short-circuit risks. More importantly, there is a conflict between temperature control and optical detection: laser heating requires the light path to reach the sample surface directly, but XPS detection requires the sample to be in a specific electronic orbital excited state, and the two are difficult to optimize together. Currently, commercial NAP-XPS equipment uses discrete temperature control modules, most of which do not have an integrated atmosphere compatibility design and lack charge management functions, resulting in insufficient data reliability in complex reaction environments.

[0005] The particularity of the synchrotron radiation experiment station further amplifies the technical bottleneck. The multi-stage differential pumping system needs to maintain a high vacuum state in the analyzer, and the sample cavity space is extremely limited, requiring a high degree of integration of the temperature control components. The existing sample rod is difficult to accommodate modules such as laser conduction, liquid cooling circulation, and electrical feedthrough within a diameter of 50mm, and it is even more impossible to achieve rapid switching over a wide temperature range. For example, when the reaction switches from low-temperature adsorption (140K) to high-temperature catalysis (1200K), the traditional heat conduction solution takes more than 10 minutes, missing the surface state changes in the initial stage of the reaction. These defects seriously restrict the in-depth mechanism research of NAP-XPS technology in the fields of energy materials, heterogeneous catalysis, etc. Summary of the Invention

[0006] 1. Technical issues:

[0007] In near-ambient-pressure X-ray photoelectron spectroscopy in-situ testing, traditional temperature control systems struggle to balance a wide temperature range (140–1500K), fast dynamic response, resistance to corrosive atmosphere interference, and multifunctional integration under space constraints, leading to high-temperature sample volatilization, electrochemical data distortion, laser reflection damage, and inefficient thermal management.

[0008] 2. Technical solution:

[0009] In order to solve the above problems, the present invention provides a composite temperature control system for a near-atmospheric pressure X-ray photoelectron spectroscopy experimental station, and its specific technical solution is as follows:

[0010] Sample tray, including:

[0011] The heating component is composed of a heating conductor, a ceramic heater and a protective layer stacked from top to bottom;

[0012] A ZrO2 support supporting the heating assembly;

[0013] The sample holder surrounds the heating assembly and the ZrO2 support, and its bottom is connected to the resistor sample fixing plate by bolts;

[0014] Sample holder, including:

[0015] KF flange 1, with both ends extending outward to form a hollow feedthrough tube, one end of the hollow feedthrough tube is provided with a rod head platform for supporting the sample holder, and the other end is provided with KF flange 2; the electrical feedthrough, thermocouple feedthrough and liquid cooling tube are arranged around the hollow feedthrough tube on the KF flange 1;

[0016] The laser emitting unit is embedded and fixed in the hollow feed-through tube through the second KF flange, and the light emitting direction is toward the rod head platform;

[0017] The water inlet and outlet of the liquid cooling tube are both located at one KF flange, the tube body is arranged along the length direction of the hollow feed-through tube, and the closed end is wrapped around the hollow feed-through tube and attached to the back of the rod head platform;

[0018] The resistance sample fixing plate is detachably fixed to the upper surface of the sample holder by screws;

[0019] The light beam output by the laser emitting unit passes through the sample holder head and irradiates the bottom of the ZrO2 holder.

[0020] Preferably, in the heating component:

[0021] The heating conductor is a Si3N4 disk with a circular through hole on its edge;

[0022] A groove through hole is formed on the edge of the ceramic heater corresponding to the circular through hole;

[0023] The protective layer is a center-sunken disk made of ZrO2, the ceramic heater is located in the center-sunken disk and is covered by a heating conductor, and an installation through hole is provided at the edge of the protective layer corresponding to the groove through hole;

[0024] The side surface of the ZrO2 support is provided with an external thread, which is screwed to the inner wall thread of the sample holder; the upper surface of the ZrO2 support is provided with a through hole.

[0025] Preferably, it also includes a cylindrical terminal.

[0026] The cylindrical terminal passes through the through hole, the mounting hole, and the groove hole in sequence from bottom to top until the end thereof is in contact with the lower end surface of the heating conductor;

[0027] The conductive screw passes through the circular through hole from the upper end surface of the heating conductor and is inserted into the central threaded hole of the cylindrical terminal to be fixedly connected to the cylindrical terminal.

[0028] Preferably, in the heating component:

[0029] The heating conductor is a Si3N4 disk;

[0030] The edge of the ceramic heater is provided with a plurality of interlaced holes;

[0031] The protective layer is a center-sunken disk made of ZrO2, the ceramic heater is located in the center-sunken disk and is covered by a heating conductor, and the protective layer and the heating conductor are both provided with elliptical through holes corresponding to the interpenetrating holes;

[0032] The side surface of the ZrO2 support is provided with an external thread, which is screwed to the inner wall thread of the sample holder; the upper surface of the ZrO2 support is provided with a through hole.

[0033] Preferably, it also includes an L-shaped terminal.

[0034] The distal end of the long side of the L-shaped terminal is cylindrical, transitioning to a flat cuboid at 1 / 2 of the long side, and smoothly connected to the short side of the L-shaped terminal;

[0035] The short side of the L-shaped terminal is a flat sheet, and the sheet is provided with a connection hole;

[0036] The short side of the L-shaped terminal passes through the elliptical through hole on the protective layer from bottom to top until the short side is in contact with the lower end surface of the ceramic heater;

[0037] The long side of the L-shaped terminal is inserted into the through hole;

[0038] An electrode fixture with a mounting hole is placed in the elliptical through hole on the heating conductor, and a conductive screw passes through the elliptical through hole on the heating conductor, the mounting hole on the electrode fixture, the through hole on the ceramic heater and the connecting hole on the sheet from top to bottom and is threadedly engaged and fixed.

[0039] Preferably, the sample holder is composed of a central hollow disk, a beam collimator, and a charge extraction layer stacked in sequence from top to bottom, and insulated from each other;

[0040] The central hollow disk is fixed to the resistance sample fixing plate with bolts;

[0041] A plurality of groups of ceramic terminals are provided on the surface of the charge extraction layer, and the ceramic terminals are electrically connected to the sample holder through wires.

[0042] Preferably, the sample holder comprises:

[0043] The edge annular platform is connected to the step of the resistance sample fixing plate through the lower threaded hole;

[0044] The hollow truncated cone has a threaded hole on its upper surface for fixing the sample to be tested.

[0045] Preferably, the lower threaded hole is provided on a spring piece fixedly connected to the edge annular platform.

[0046] Preferably, the heating conductor and the protective layer are made of ZrO2 or Si3N4.

[0047] Preferably, a tube clamp is clamped at the closed end of the liquid cooling tube, and the tube clamp is clamped between the rod head platform and the tube clamp by a collar, and the collar is fixed to the outer surface of the hollow feed-through tube by screws.

[0048] 3.Beneficial effects:

[0049] The present invention realizes seamless switching of three temperature control modes, namely resistance heating, laser heating and liquid cooling, in a single system through the coordinated design of the sample holder and the sample rod, greatly broadening the operable temperature window from conventional room temperature to 800K to 140K~1500K, and the heating and cooling rates can be controlled at 5K / min and greater than 10K / s respectively, which not only meets the long-term constant temperature conditions required for catalytic reactions, but also takes into account the rapid quenching requirements required for surface adsorption experiments; Si3N4 and ZrO2, low thermal expansion, high melting point, chemically inert ceramic materials, are used to construct the heating conductor, protective layer and support, so that the sample holder can operate continuously for more than 100 hours in reaction atmospheres such as 25mbar hydrogen, carbon monoxide or water vapor without corrosion, cracking or resistance drift, significantly improving the reliability and service life of the system; through the planar heating of the ceramic heater The structure and the central sunken protective layer are wrapped in a design that allows the heat flow to be uniformly conducted vertically upward to the sample, with a temperature gradient of less than 3K / mm. Combined with PID closed-loop control, the temperature control accuracy can reach ±1K, effectively distinguishing the influence of thermal effects and real reactions on the surface chemical state. The laser heating path utilizes an 808–940nm near-infrared fiber laser. Through coaxial coupling with a beam collimator and a central hollow disk, the laser energy is deposited on the heating component on the back of the sample with millimeter-level precision, making it particularly suitable for localized heating of milligram-level micro-samples. The charge extraction layer uses ceramic terminals to connect to the sample holder, which can extract the surface charges generated by electron beam or X-ray irradiation in real time, eliminating the displacement broadening of the photoelectron spectrum caused by the electric field and improving the accuracy of binding energy measurement. The interface solution of KF flange and multi-stage differential pumping keeps the sample area at near-normal pressure while the analyzer area remains less than 1×10 -9 mbar high vacuum enables in-situ testing under in-situ atmosphere; the two mechanical fixing methods, cylindrical terminals and L-shaped terminals, back each other up, which not only simplifies the assembly process but also facilitates subsequent maintenance and troubleshooting; the overall modular design allows the sample holder, sample rod, liquid cooling tube, and laser fiber head to be independently disassembled and upgraded, reducing the downtime and maintenance costs of the experimental station and significantly improving the versatility, stability and data reliability of the near-atmospheric pressure X-ray photoelectron spectroscopy experimental station. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] Figure 1 This is a schematic diagram of the overall structure of the sample holder of the present invention (assembled);

[0051] Figure 2 This is a schematic diagram of the overall structure of the sample holder of the present invention;

[0052] Figure 3 This is a schematic diagram of the sample rod structure of the present invention (unassembled);

[0053] Figure 4 This is a schematic diagram of the liquid cooling tube structure of the present invention;

[0054] Figure 5 This is a schematic diagram of the structure of the laser fiber head of the present invention;

[0055] Figure 6 This is a schematic diagram of the pipe clamp structure of the present invention;

[0056] Figure 7 This is a schematic diagram of the heating conductor structure of the present invention;

[0057] Figure 8 This is a schematic structural diagram of the ceramic heater of the present invention;

[0058] Figure 9 Schematic diagram of the protective layer structure of the present invention;

[0059] Figure 10 Schematic diagram of the sample holder structure of the present invention;

[0060] Figure 11 This is a schematic diagram of the structure of the resistor sample fixing plate of the present invention;

[0061] Figure 12 This is a schematic diagram of the cylindrical terminal structure of the present invention;

[0062] Figure 13 Schematic diagram of the ZrO2 support structure of the present invention;

[0063] Figure 14 for Figure 2 Exploded diagram;

[0064] Figure 15 This is a schematic diagram of the overall structure of the heating assembly when the terminal is an L-shaped terminal;

[0065] Figure 16 This is a schematic diagram of the L-shaped terminal structure of the present invention;

[0066] Figure 17 for Figure 15 Exploded diagram;

[0067] Figure 18 This is a schematic diagram of the sample support head structure of the present invention;

[0068] Figure: 1. Sample holder; 101. Upper threaded hole; 102. Lower threaded hole; 103. Edge ring platform; 104. Spring clip; 105. Hollow cone; 106. Internal thread; 2. Resistor sample fixing plate; 201. Step; 3. Heating conductor; 301. Circular through hole; 302. Oval through hole; 4. Ceramic heater; 401. Grooved through hole; 402. Through hole; 5. Protective layer; 501. Mounting through hole; 6. ZrO2 support; 601. Through hole; 602. External thread; 7. Cylindrical terminal; 701. Center threaded hole; 8. L-shaped terminal Column; 801, thin sheet; 802, connecting hole; 9, center hollow disk; 10, beam collimator; 11, charge derivation layer; 111, ceramic terminal; 112, electrode fixture; 12, liquid cooling tube; 121, water inlet; 122, water outlet; 123, closed end; 124, pipe clamp; 13, collar; 14, KF flange one; 141, hollow feedthrough tube; 142, rod head platform; 143, KF flange two; 144, electrical feedthrough; 145, thermocouple feedthrough; 146, window; 151, KF flange three; 152, laser tube; 153, laser head. DETAILED DESCRIPTION

[0069] To make the purpose, technical solutions, and advantages of this application more clear, the technical solutions in the embodiments of this application will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the described embodiments are part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this invention.

[0070] The whole system is centered around the sample holder. Figure 2As shown, the sample holder comprises, from top to bottom, a sample holder 1, a heating assembly, a ZrO2 support 6, and a resistor sample fixing plate 2. The resistor sample fixing plate 2 is integrally sintered from ZrO2, with a circular outer contour and three steps 201 uniformly machined on the annular surface. Each step 201 has a threaded hole at its center for bolting to the edge ring platform 103 of the sample holder 1. A spring clip 104 is disposed between the step 201 and the ring platform. One end of the spring clip 104 is integrally connected to the ring platform, while the other end is suspended and defines a lower threaded hole 102. Optionally, the spring clip 104 can be laser-cut from the edge ring platform 103 of the sample holder 1, ensuring that the integral connection between the spring clip 104 and the edge ring platform 103 is only a narrow portion. This narrow connection improves the elastic deformation capacity of the spring clip 104. When the system undergoes high-temperature cycling at 800-1200K, the spring clip 104 absorbs thermal expansion differences through elastic deformation, preventing thread jamming or ceramic cracking. The sample holder 1 is made of ZrO2, a material of the same material, and is cylindrical in shape. Its bottom outer edge is an annular platform 103. The lower surface of the platform mates with the resistor sample mounting plate 2, while the upper surface of the platform extends outward from a hollow cone 105. The inner wall of the hollow cone 105 is machined with internal threads 106 for screwing onto the ZrO2 support 6. The upper surface of the hollow cone 105 is flat and has six upper threaded holes 101. Experimenters can directly adhere powder samples to this surface with conductive silver glue, or mechanically secure sheet or film samples with screws, thus accommodating samples of varying morphologies and sizes.

[0071] The heating component is located inside the cavity of the hollow cone 105, and is composed of a heating conductor 3, a ceramic heater 4 and a protective layer 5 coaxially stacked from top to bottom. The heating conductor 3 can be made of Si3N4 or ZrO2. In this embodiment, a Si3N4 disc is used with a thickness of 2 mm, a diameter that matches the outer diameter of the protective layer 5, and two circular through holes 301 are evenly opened on the edge. The ceramic heater 4 is a planar heating element with an outer diameter consistent with that of the heating conductor 3. A groove through hole 401 is opened at the position corresponding to the circular through hole 301. The protective layer 5 is a center-sunken disc made of ZrO2. The depth of the concave center of the disc is consistent with the thickness of the ceramic heater 4, so that the ceramic heater 4 is completely covered by the heating conductor 3 after being embedded in the sinking area, realizing vertical upward conduction of heat flow and preventing lateral heat loss. A mounting through hole 501 is opened at the edge of the protective layer 5 corresponding to the groove through hole 401 for passing the terminal.

[0072] The ZrO2 support 6 is a cylinder with an external thread 602 processed on the side wall, which is screwed to the internal thread 106 on the inner wall of the hollow cone 105; a through hole 601 is provided on the edge of its upper surface; the through hole 601, the mounting through hole 501, the groove through hole 401, and the circular through hole 301 are coaxial and together constitute the channel of the terminal.

[0073] For the installation of the terminal post, this embodiment provides two equivalent paths:

[0074] The first path involves the cylindrical terminal 7: A slender cylindrical terminal 7 is prepared, made of a nickel-chromium alloy and nickel-plated to enhance oxidation resistance. The cylindrical terminal 7 is threaded upward, sequentially through the through-hole 601 of the ZrO2 support 6, the mounting hole 501 of the protective layer 5, and the recessed hole 401 of the ceramic heater 4, until its upper end abuts the lower end of the heating conductor 3. A conductive screw is then threaded from the upper end of the heating conductor 3 through the circular through-hole 301 and into the central threaded hole 701 of the cylindrical terminal 7. Tighten the screw to a torque of 0.8 N·m, thus forming an integrated heating assembly with the heating conductor 3, ceramic heater 4, protective layer 5, and ZrO2 support 6.

[0075] The second is the path of the L-shaped terminal 8: prepare an L-shaped terminal 8, the distal end of the long side of which remains cylindrical, and the diameter is loosely matched with the through hole 601. The proximal 1 / 2 of the long side is milled into a flat rectangular parallelepiped, and smoothly transitions with the short side. The short side is a flat thin sheet 801, and two circular connecting holes 802 are opened on the thin sheet 801; the original groove through hole 401 of the ceramic heater 4 is changed to an interlaced hole 402, and the groove through holes 401 corresponding to the protective layer 5 and the heating conductor 3 are changed to an elliptical through hole 302 to accommodate the short side of the L-shaped terminal 8; the electrode fixture 112 is placed in the elliptical through hole 302 on the heating conductor 3. The electrode fixture 112 is an elliptical thin sheet 801 with a mounting hole opened on it. During assembly, first insert the long side of the L-shaped terminal 8 into the through hole 601, and the short side passes through the elliptical through hole 302 of the protective layer 5 from bottom to top until it fits with the lower end surface of the ceramic heater 4; then place the electrode fixture 112 in the elliptical through hole 302 on the heating conductor 3, so that the elliptical through hole 302, the mounting hole, the insertion hole 402, and the connecting hole 802 are coaxial, and finally pass two sets of conductive screws from top to bottom through the electrode fixture 112, the heating conductor 3, the ceramic heater 4 and screw them into the connecting hole 802 on the short side to complete the fixation.

[0076] Both paths ensure that the current is introduced from the terminal, generates Joule heat through the ceramic heater 4, and then evenly diffuses to the sample through the heating conductor 3. The entire heating assembly is suspended inside the hollow cone 105 by the ZrO2 support 6 and has no direct contact with the sample holder 1, thereby reducing the thermal bridge effect.

[0077] After the heating assembly and the sample holder 1 are screwed together, the sample holder 1 is fixed to the step 201 of the resistance sample fixing plate 2 through the lower threaded hole 102 of the edge annular platform 103 of the sample holder 1. At this time, the entire sample holder is assembled.

[0078] like Figure 18As shown, the sample holder head serves as a bridge between the sample holder and the sample rod. From top to bottom, it consists of three layers: a central hollowed-out disk 9, a beam collimator 10, and a charge extraction layer 11. Each layer is insulated and connected via stainless steel screws encased in a hollow ceramic tube. The central hollowed-out disk 9 is disc-shaped, with the central hollowed-out area matching the inner diameter of the resistor sample holder plate 2. The two are fastened together by bolts, ensuring that laser light or X-rays can vertically penetrate the central hollowed-out area and irradiate the bottom wall of the ZrO2 support 6. The beam collimator 10 is located below the central hollowed-out disk 9. Optionally, the beam collimator 10 is a tungsten steel ring with a blackened inner surface to absorb reflected laser light and prevent energy from being transferred back to the sample rod. The charge extraction layer 11 is located at the bottom and is fixedly connected to the rod head platform 142 via screws. Three ceramic terminals 111 are welded to the surface of the charge extraction layer 11. The terminals are electrically connected to the resistor sample holder plate 2 via wires. When charge accumulates on the sample holder surface due to electron or ion beam irradiation, it can be extracted through the terminals to prevent electric field interference with the photoelectron signal.

[0079] like Figure 1 As shown, the sample holder is based on KF flange 14. A hollow feedthrough tube 141 extends outward from the center of the outer surface of KF flange 14. One end of hollow feedthrough tube 141 is connected to KF flange 2 143, and the other end is provided with a rod head platform 142 for supporting the sample holder. Optionally, multiple windows 146 are spaced along the length of hollow feedthrough tube 141 to reduce the weight of the entire sample holder and facilitate observation of the operating status of the laser fiber head. A laser fiber head is coaxially inserted into hollow feedthrough tube 141 and secured via the flange connection between KF flange 2 143 and KF flange 3 151. The laser fiber head consists of KF flange 3 151, laser tube 152, and laser head 153. The laser fiber head is electrically connected to the external laser controller. The laser tube 152 is a slender stainless steel tube, and the far end is expanded to form the laser head 153. The end face of the laser head 153 is flush with the end face of the rod head platform 142, ensuring that the laser beam can be vertically irradiated to the bottom of the ZrO2 support 6.

[0080] The laser wavelength is selectable between 808 and 940 nm, with continuously adjustable power up to 30 W and a spot diameter of 3 mm. The energy deposition area precisely coincides with the sample position. Four feedthroughs are symmetrically arranged around the hollow feedthrough tube on the KF flange 14, connecting two electrical feedthroughs 144 and two thermocouple feedthroughs 145, respectively. The electrical feedthroughs 144 are connected to cylindrical terminals 7 or L-shaped terminals 8 via high-temperature wires, providing a programmable current of 0-5 A to the ceramic heater 4. The thermocouple feedthroughs 145 use K-type thermocouples, with the probes positioned closely against the bottom surface of the sample holder 1, providing real-time temperature feedback to the PID controller with a temperature control accuracy of ±1 K. In addition, the KF flange 14 is also provided with two feed-through tubes, which serve as the water inlet 121 and the water outlet 122 of the liquid cooling tube 12 respectively. The liquid cooling tube 12 is a copper spiral tube with a diameter of 6mm and a wall thickness of 1mm. The body of the liquid cooling tube 12 is arranged axially along the outside of the hollow feed-through tube. The closed end 123 is bent by a precision bending tool and fits against the back of the rod head platform 142. The contact surface can be coated with thermal grease to enhance thermal coupling. Optionally, six stainless steel screws are used to fix the collar 13 to the outer wall of the hollow feed-through tube 141, and the tube clamp 124 is clamped and fixed between the collar 13 and the rod head platform 142. A groove is provided in the tube clamp 124 that is consistent with the direction and size of the closed end 123 of the liquid cooling tube 12. The groove engages and limits the closed end 123 of the liquid cooling tube 12 and presses it to the back of the rod head platform 142, so that the liquid cooling tube 12 is structurally stable while being in full contact with the rod head platform 142 to prevent vibration-induced coolant leakage. Figure 6 As mentioned above, the tube clamp 124 is an arc-shaped structure that can be directly engaged laterally on the outer wall of the hollow feedthrough tube 141 to secure the closed section of the liquid cooling tube 12. Optionally, the collar 13 can be composed of two semi-annular structures, the inner diameter of which after assembly is consistent with the outer diameter of the hollow feedthrough tube 141. The hollow feedthrough tube 141 and the collar 13 are both provided with threaded holes to facilitate the use of stainless steel screws to secure the collar 13 to the outer wall of the hollow feedthrough tube 141.

[0081] Deionized water is used as the coolant with a flow rate of 2 L / min, which can maintain the temperature of the laser head 153 and the rod head platform 142 near room temperature to avoid thermal drift.

[0082] The entire sample rod is fixed to the flange of the experimental station chamber by KF flange-14 bolts. The KF flange-14 and the chamber are sealed with oxygen-free copper gaskets to ensure no leakage in near-normal pressure atmosphere up to 30mbar. The experimental station chamber is connected to a multi-stage differential pump to maintain the analyzer area better than 1×10 -9 mbar high vacuum, while allowing the sample area to maintain a near-normal pressure environment, enabling in-situ testing.

[0083] During the experimental operation phase, the powdered catalyst sample was first placed on the upper surface of the hollow cone 105 by a manipulator and fixed with conductive silver glue. Then the cavity was closed, the foreline pump and the molecular pump were started, and the vacuum was better than 1×10 -6 mbar, 25mbar of carbon monoxide was introduced into the cavity, the ceramic heater 4 was started, and the temperature was raised to 800K at 5K / min using the PID program and maintained for 30min. During this period, the X-ray source and the energy analyzer collected the photoelectron energy spectrum in real time to observe the evolution of carbon and oxygen species on the catalyst surface; when rapid quenching was required, the ceramic heater 4 was turned off and the liquid cooling tube 12 was turned on at the same time. The sample temperature dropped to room temperature within 90s, and then the bottom surface of the ZrO2 support 6 was irradiated with a power of 20W through the laser fiber head. The heat was conducted to the back of the sample through the heat transfer of the heating component, and the local temperature was raised to 1000K again to simulate the hot spot effect. The temperature curve of the whole process was controlled by the thermocouple closed loop, and the laser power was modulated in real time by the laser controller to ensure the safety of the experiment and the reliability of the data.

[0084] This embodiment achieves coordinated temperature control using resistance heating, laser heating, and liquid cooling through the modular design of the sample holder and sample rod, covering a wide temperature range of 140K to 1500K; the two terminal assembly methods provide process redundancy, facilitating subsequent maintenance; the use of high-temperature and corrosion-resistant materials such as Si3N4 and ZrO2 ensures the long-term stable operation of the system in reaction atmospheres containing hydrogen and carbon monoxide; the beam collimator 10 and the charge derivation layer 11 effectively suppress laser reflection and charge accumulation, thereby improving test accuracy; the interface design of the KF flange and multi-stage differential pumping enables the system to operate in a near-normal pressure environment while maintaining a high vacuum in the analyzer, meeting the requirements of in-situ dynamic surface analysis.

[0085] Although the present invention has been described in detail above using general descriptions and specific embodiments, it will be apparent to those skilled in the art that modifications and improvements may be made thereto. Therefore, such modifications and improvements, without departing from the spirit of the present invention, are intended to be within the scope of protection claimed herein.

Claims

1. A composite temperature control system for a near-atmospheric pressure X-ray photoelectron spectroscopy experimental station, characterized in that: include: Sample tray, including: The heating component is composed of a heating conductor (3), a ceramic heater (4) and a protective layer (5) stacked from top to bottom; A ZrO2 support (6) supporting the heating assembly; A sample holder (1) enclosing the heating assembly and the ZrO2 support (6), the bottom of which is connected to the resistance sample fixing plate (2) via bolts; Sample holder, including: KF flange one (14), both ends of which extend outward to form a hollow feedthrough tube (141), one end of the hollow feedthrough tube (141) is provided with a rod head platform (142) for supporting the sample holder, and the other end is provided with KF flange two (143); an electrical feedthrough (144), a thermocouple feedthrough (145) and a liquid cooling tube (12) are arranged on the KF flange one (14) around the hollow feedthrough tube (141); A laser emitting unit is embedded and fixed in the hollow feed-through tube (141) through the second KF flange (143), and the light emitting direction is toward the rod head platform (142); The water inlet (121) and the water outlet (122) of the liquid cooling tube (12) are both located at the KF flange 1 (14), the tube body is arranged along the length direction of the hollow feed-through tube (141), and the closed end (123) is wound around the hollow feed-through tube (141) and then adhered to the back of the rod head platform (142); The resistance sample fixing plate (2) is detachably fixed to the upper surface of the sample holder by screws; The light beam output by the laser emitting unit passes through the sample holder head and irradiates the bottom of the ZrO2 holder (6); The sample holder is composed of a central hollow disk (9), a beam collimator (10), and a charge extraction layer (11) stacked in sequence from top to bottom and insulated from each other; The central hollow disk (9) is fixed to the resistance sample fixing plate (2) by bolts; A plurality of groups of ceramic terminals (111) are provided on the surface of the charge extraction layer (11), and the ceramic terminals (111) are electrically connected to the sample holder via wires.

2. The composite temperature control system for a near-atmospheric pressure X-ray photoelectron spectroscopy experimental station according to claim 1, characterized in that: In the heating assembly: The heating conductor (3) is a Si3N4 disk with a circular through hole (301) formed on its edge; A groove through-hole (401) is formed on the edge of the ceramic heater (4) corresponding to the circular through-hole (301); The protective layer (5) is a center-sunken disk made of ZrO2, the ceramic heater (4) is located in the center-sunken disk and is covered by the heating conductor (3), and a mounting through hole (501) is formed on the edge of the protective layer (5) corresponding to the groove through hole (401); The side of the ZrO2 support (6) is provided with an external thread (602) which is screwed to the inner wall of the sample holder (1); and the upper surface of the ZrO2 support (6) is provided with a through hole (601).

3. The composite temperature control system for a near-atmospheric pressure X-ray photoelectron spectroscopy experimental station according to claim 2, characterized in that: Also includes cylindrical terminal (7), The cylindrical terminal (7) passes through the through hole (601), the mounting through hole (501), and the groove through hole (401) in sequence from bottom to top until the end thereof abuts against the lower end surface of the heating conductor (3); The conductive screw passes through the circular through hole (301) from the upper end surface of the heating conductor (3) and is inserted into the central threaded hole (701) of the cylindrical terminal (7) to be fixedly connected to the cylindrical terminal (7).

4. The composite temperature control system for a near-atmospheric pressure X-ray photoelectron spectroscopy experimental station according to claim 1, characterized in that: In the heating assembly: The heating conductor (3) is a Si3N4 disk; The ceramic heater (4) has a plurality of through holes (402) formed on its edge; The protective layer (5) is a center-sunken disk made of ZrO2, the ceramic heater (4) is located in the center-sunken disk and is covered by the heating conductor (3), and the protective layer (5) and the heating conductor (3) are both provided with elliptical through holes (302) corresponding to the through holes (402); The side of the ZrO2 support (6) is provided with an external thread (602) which is screwed to the inner wall of the sample holder (1); and the upper surface of the ZrO2 support (6) is provided with a through hole (601).

5. The composite temperature control system for a near-atmospheric pressure X-ray photoelectron spectroscopy experimental station according to claim 4, characterized in that: Also includes L-shaped binding posts (8), The distal end of the long side of the L-shaped terminal (8) is cylindrical, transitioning to a flat rectangular parallelepiped at 1 / 2 of the long side, and smoothly connected to the short side of the L-shaped terminal (8); The short side of the L-shaped terminal (8) is a flat sheet (801), and the sheet (801) is provided with a connection hole (802); The short side of the L-shaped terminal (8) passes through the elliptical through hole (302) on the protective layer (5) from bottom to top until the short side is in contact with the lower end surface of the ceramic heater (4); The long side of the L-shaped terminal (8) is inserted into the through hole (601); An electrode fixture (112) with a mounting hole is placed in the elliptical through hole (302) on the heating conductor (3), and a conductive screw is sequentially passed through the elliptical through hole (302) on the heating conductor (3), the mounting hole on the electrode fixture (112), the through hole (402) on the ceramic heater (4), and the connecting hole (802) on the sheet (801) from top to bottom to be threadedly engaged and fixed.

6. The composite temperature control system for a near-atmospheric pressure X-ray photoelectron spectroscopy experimental station according to claim 1, characterized in that: The sample rack (1) comprises: The edge annular platform (103) is connected to the step (201) of the resistance sample fixing plate (2) through the lower threaded hole (102); The hollow truncated cone (105) has an upper threaded hole (101) on its upper surface for fixing the sample to be tested.

7. The composite temperature control system for a near-atmospheric pressure X-ray photoelectron spectroscopy experimental station according to claim 6, characterized in that: The lower threaded hole (102) is formed on a spring piece (104) fixedly connected to the edge annular platform (103).

8. The composite temperature control system for a near-atmospheric pressure X-ray photoelectron spectroscopy experimental station according to claim 1, characterized in that: The heating conductor (3) and the protective layer (5) are made of ZrO2 or Si3N4.

9. The composite temperature control system for a near-atmospheric pressure X-ray photoelectron spectroscopy experimental station according to claim 1, characterized in that: The closed end (123) of the liquid cooling tube (12) is engaged with a tube clamp (124), and the tube clamp (124) is clamped between the rod head platform (142) and the tube clamp (124) by a collar (13), and the collar (13) is fixed to the outer surface of the hollow feed-through tube (141) by screws.

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