Cold plasma high temperature raman cell

Abstract

This invention provides a cold plasma high-temperature Raman cell, comprising a main cell body; a water-cooled base; and a plasma generator, which is integrally installed in the middle of the reaction chamber. The plasma generator includes a ceramic flange base, a ceramic central tube fixed to the center of the surface of the ceramic flange base, and a cylindrical high-voltage electrode inserted inside the ceramic central tube. Ceramic heating tubes are concentrically spaced around the ceramic central tube, with a heating gap between the ceramic heating tubes and the ceramic central tube. An annular low-voltage electrode is fitted to the outer top of the ceramic heating tubes. The gap between the ceramic heating ring and the ceramic protective sleeve is filled with heat-insulating material. Other components include a ceramic sample cup; an external electrode; a quartz window; and a cover plate. This invention integrates three independent functional modules—a resistance heating system, a low-temperature plasma generation system, and a Raman optical detection system—through a unique reaction chamber structure design, enabling the study and observation of samples under the combined effects of plasma and high temperature.

Description

Technical Field

[0001] This invention relates to the field of Raman cell technology, and more specifically to a cold plasma high-temperature Raman cell. Background Technology

[0002] Raman spectroscopy, a non-destructive analytical technique based on the Raman scattering effect, provides fingerprint information of molecular vibrational energy levels and has become an important tool for studying surface chemistry, catalytic reaction intermediates, and material phase transitions. To achieve observation under real reaction conditions, the development of high-temperature in-situ Raman spectroscopy is particularly important. Currently, commercially available high-temperature in-situ reaction cells typically use resistance heating rods or furnaces to heat samples, enabling in-situ studies of surface structural changes in catalytic materials during thermocatalysis.

[0003] On the other hand, plasma catalysis, as an emerging technology, combines low-temperature plasma with heterogeneous catalysis, providing a new approach to activate inert molecules (such as CH4, CO2, and N2) under relatively mild conditions. The core scientific challenge of this technology lies in understanding the synergistic mechanism between plasma-generated active species (such as excited-state molecules, ions, and free radicals) and the catalyst surface. However, current research on plasma catalysis mechanisms heavily relies on offline characterization after the reaction, lacking effective means for real-time, in-situ monitoring of catalyst surface states, adsorbed species, and transient intermediates during the reaction process.

[0004] Conventional high-temperature Raman reaction chambers lack the ability to generate stable, uniform plasma; while conventional plasma reactors lack precise temperature control systems and in-situ optical windows and optical path designs compatible with Raman optics systems. The primary technical challenge lies in integrating heating, plasma excitation, and in-situ optical detection within a single reaction chamber, ensuring that each functional module works collaboratively without interference.

[0005] The design of the reaction chamber must simultaneously meet the requirements of structural stability at high temperatures, the specific atmosphere and electrode configuration required for plasma discharge, and unobstructed optical pathways. Furthermore, the reactor material must withstand high temperatures and plasma erosion while maintaining good optical properties. Current technologies lack integrated design solutions that can satisfy these comprehensive requirements.

[0006] Therefore, there is currently a lack of a dedicated system capable of simulating real plasma catalytic reaction conditions, providing a controllable temperature environment, and enabling high signal-to-noise ratio, in-situ Raman spectroscopy characterization of the catalyst surface under these conditions. This technological gap severely restricts our in-depth understanding of the plasma-catalyst synergistic mechanism and the design and development of high-performance catalysts. Summary of the Invention

[0007] To address the shortcomings of existing technologies, this invention provides a cold plasma high-temperature Raman cell, which solves the problems mentioned in the background art.

[0008] To achieve the above objectives, the present invention provides the following technical solution:

[0009] A cold plasma high-temperature Raman cell includes: a main cell body with a reaction chamber in its center; a water-cooled base flush with the bottom surface of the main cell body; a plasma generator installed in the center of the reaction chamber; the plasma generator includes a ceramic flange base, a ceramic central tube fixed in the center of the surface of the ceramic flange base, a cylindrical high-voltage electrode inserted inside the ceramic central tube; ceramic heating tubes concentrically spaced outside the ceramic central tube, with a heating gap between the ceramic heating tubes and the ceramic central tube; an annular low-voltage electrode fitted on the top outer side of the ceramic heating tubes; heat insulation material filling the gap between the ceramic heating ring and the ceramic protective sleeve; a ceramic sample cup inserted into the heating gap and overlapping the annular low-voltage electrode, with the ceramic central tube and ceramic heating tubes providing double-stage positioning of the ceramic sample cup; an outer electrode horizontally installed on the side of the main cell body, with its inner end extending into the reaction chamber; a quartz window covering the top of the main cell body; and a cover plate covering the top of the quartz window and fixedly connected to the main cell body by screws.

[0010] Furthermore, the water-cooled base includes a base plate with a mating hole in the middle and a water-cooling ring at the edge of the base plate. The two ends of the water-cooling ring are symmetrically connected to extension seats, and the ends of the extension seats are connected to water-cooling connectors.

[0011] Furthermore, the bottom surface of the main tank body is provided with an assembly ring groove, and the two ends of the assembly ring groove are connected with outward notches. A docking block is provided at the center of the bottom surface of the main tank body; the water cooling ring is embedded in the assembly ring groove, the outward seat is embedded in the outward notch, and the docking block is inserted into the mating hole.

[0012] Furthermore, the main pool body is rectangular, and the four outer sides of the main pool body are respectively the first side, the second side, the third side and the fourth side. The first side and the third side are arranged opposite to each other. An external electrode is installed on the first side, an electrode lead connector and a heating lead connector are provided on the third side, and an air passage interface is provided on the second side.

[0013] Furthermore, a wiring cavity is provided in the middle of the bottom surface of the reaction chamber, and wiring straight grooves are symmetrically provided at both ends of the wiring cavity, with the two ends of the wiring straight grooves facing the first side and the third side, respectively.

[0014] Furthermore, the ceramic flange base plate has a circular groove on its surface, the inner diameter of which is the same as the outer diameter of the ceramic protective sleeve, and a wiring hole is provided inside the ceramic flange.

[0015] Furthermore, the outer diameter of the upper section of the cylindrical high-voltage electrode is larger than that of the lower section, the upper end of the cylindrical high-voltage electrode is stopped at the top of the ceramic central tube, and the lower section of the cylindrical high-voltage electrode penetrates the ceramic central tube and extends into the wiring cavity.

[0016] Furthermore, the height of the ceramic heating tube is greater than the height of the ceramic center tube, and the bottom surface of the annular low-pressure electrode is provided with an annular groove adapted to the top of the ceramic heating tube. The inner diameter of the annular low-pressure electrode is the same as the inner diameter of the ceramic heating tube.

[0017] Furthermore, the ceramic sample cup includes a main body that is inserted into the heating gap. The bottom surface of the main body has a lower docking cavity. The upper section of the cylindrical high-voltage electrode and the ceramic central tube extend into the lower docking cavity. The top center of the main body has a central boss. The outer periphery of the central boss is a sample ring cavity for storing the sample. The top outer periphery of the main body has an overlapping ring.

[0018] Furthermore, the ceramic protective sleeve has symmetrically provided material-removing notches on its sides for easy removal of the ceramic sample cup.

[0019] This invention provides a cold plasma high-temperature Raman cell. Compared with the prior art, it has the following advantages:

[0020] The resistance heating system, the low-temperature plasma generation system, and the Raman optical detection system—three independent functional modules—are integrated into a single unit through a unique reaction chamber structure design. This allows for the study and observation of samples under the combined effects of plasma and high temperature, enabling real-time, in-situ capture of changes in the molecular structure of the catalyst surface, the formation and consumption of reaction intermediates, and the dynamic evolution of active sites. Furthermore, the entire Raman cell structure is compact, easy to assemble, and the modules are easily disassembled, simultaneously meeting one or more testing environment requirements. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 A schematic diagram of the overall structure of the present invention is shown;

[0023] Figure 2 A schematic diagram of the water-cooled base structure of the present invention is shown;

[0024] Figure 3 A schematic diagram of the bottom structure of the main pool body of the present invention is shown;

[0025] Figure 4 A schematic diagram of the top structure of the main pool body of the present invention is shown;

[0026] Figure 5 A schematic diagram of the cross-sectional structure of the main pool body of the present invention is shown;

[0027] Figure 6 A schematic diagram of the internal bottom structure of the reaction chamber of the present invention is shown;

[0028] Figure 7 A schematic diagram of the separation structure of the plasma generator of the present invention is shown;

[0029] Figure 8 A schematic diagram of the ceramic flange base structure of the present invention is shown;

[0030] Figure 9 A schematic diagram of the ceramic sample cup installation structure of the present invention is shown;

[0031] Figure 10 A schematic diagram of the ceramic sample cup structure of the present invention is shown;

[0032] As shown in the figure:

[0033] 100. Main pool body,

[0034] 110. Assembly ring groove; 111. Outward notch; 120. Connecting block; 130. Reaction chamber; 131. Straight cable routing groove; 132. Cable routing cavity.

[0035] 140. Sealing ring groove; 150. Gas passage interface; 160. Electrode lead connector; 170. Heating lead connector.

[0036] 200. Water-cooled base; 210. Base plate; 211. Mating hole; 220. Water-cooled ring; 230. Extension seat; 240. Water-cooled connector.

[0037] 300. External electrode.

[0038] 400. Plasma generator

[0039] 410. Ceramic flange base; 411. Circular groove; 412. Cable routing hole.

[0040] 420. Ceramic center tube.

[0041] 430. Ceramic protective sleeve; 431. Material receiving notch.

[0042] 440. Cylindrical high-voltage electrode.

[0043] 450. Ring-shaped low-voltage electrode.

[0044] 460. Ceramic heating element

[0045] 500. Ceramic sample cup; 510. Main tube; 520. Lower connecting cavity; 530. Sample ring cavity; 540. Central boss; 550. Overlapping ring.

[0046] 600, Quartz window,

[0047] 700, cover plate. Detailed Implementation

[0048] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention are described clearly and completely. Obviously, the described embodiments are only some embodiments of the present invention, 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.

[0049] To address the technical problems in the background art, the following cold plasma high-temperature Raman cell is proposed:

[0050] Combination Figures 1-10 As shown, this invention discloses a cold plasma high-temperature Raman cell, the specific technical structure of which is as follows:

[0051] This device includes a main cell 100, which is made of PEEK material, with a temperature resistance of up to 250℃. It has excellent insulation, sealing, and structural stability, making it suitable for high-temperature experimental conditions. The main cell 100 has a rectangular structure, with a reaction chamber 130 centrally located inside, serving as the core area for sample reaction, plasma discharge, and optical detection.

[0052] An assembly ring groove 110 is provided on the bottom surface of the main tank body 100. The two ends of the assembly ring groove 110 are connected to the outward notch 111. A docking block 120 is provided at the center of the bottom surface of the main tank body 100 for precise alignment and assembly of the water-cooled base 200.

[0053] The main tank 100 has four outer peripheral sides, which are arranged in opposite directions: the first side, the third side, the second side, and the fourth side. The first side is equipped with an external electrode 300, the third side is equipped with an electrode lead connector 160 and a heating lead connector 170, and the second side is equipped with a gas path interface 150, which respectively meet the functions of electrode conduction, heating power supply, and atmosphere replacement.

[0054] A wiring cavity 132 is opened in the middle of the bottom surface of the reaction chamber 130. Wiring straight grooves 131 are symmetrically arranged at both ends of the wiring cavity 132. The two sets of wiring straight grooves 131 face the first side and the third side of the main tank body 100 respectively, so as to realize the neat layout of the internal and external leads and avoid messy lines and high temperature aging.

[0055] A water-cooled base 200 is flush with the bottom surface of the main tank 100 and embedded in the base to achieve overall circulating water cooling and protection for the equipment. The water-cooled base 200 includes a base plate 210 with a mating hole 211 in the middle. Water-cooled rings 220 are arranged along the edge of the base plate 210. Extended seats 230 are symmetrically connected to both ends of the water-cooled rings 220. Water-cooled connectors 240 are fitted at the ends of the extended seats 230 for connecting to an external water chiller to achieve water circulation heat exchange and cooling.

[0056] The water-cooling ring 220 is embedded in the assembly ring groove 110 of the main tank body 100, the extension seat 230 is embedded in the extension notch 111, and the center mating hole 211 of the base plate 210 is inserted and mated with the docking block 120 of the main tank body 100. The assembly is tight and the positioning is accurate, which can cool the main tank body 100 with water from all directions, effectively avoid overheating of the tank body and aging of components under high temperature conditions, and ensure long-term stable operation of the equipment.

[0057] The plasma generator 400 is integrally assembled in the middle of the reaction chamber 130. The plasma generator 400 includes a ceramic flange base 410. A ceramic central tube 420 is fixed in the middle of the surface of the ceramic flange base 410. A wiring hole 412 is opened inside the ceramic flange base 410 and a circular groove 411 is opened on the surface. The inner diameter of the circular groove 411 matches the outer diameter of the ceramic protective sleeve 430, so as to achieve precise positioning and assembly of the ceramic protective sleeve 430.

[0058] A cylindrical high-voltage electrode 440 is inserted inside the ceramic central tube 420. The outer diameter of the upper section of the cylindrical high-voltage electrode 440 is larger than that of the lower section. The upper end is stopped and limited at the top of the ceramic central tube 420, and the lower section extends through into the wiring cavity 132 to complete the electrode lead layout. Ceramic heating tubes 460 are concentrically spaced outside the ceramic central tube 420. The height of the ceramic heating tubes 460 is greater than that of the ceramic central tube 420, forming a uniform heating gap between them.

[0059] A ring-shaped low-voltage electrode 450 is fitted onto the outer side of the top of the ceramic heating tube 460. The bottom surface of the ring-shaped low-voltage electrode 450 has an annular groove adapted to the top of the ceramic heating tube 460. The inner diameter of the ring-shaped low-voltage electrode 450 is the same as that of the ceramic heating tube 460, ensuring precise alignment and uniform discharge. The gap between the ceramic heating tube 460 and the ceramic protective sleeve 430 is filled with heat-insulating material to achieve high-temperature heat insulation, reduce heat loss, and improve heating efficiency. Symmetrical material-removing notches 431 are provided on the side of the ceramic protective sleeve 430 for quick disassembly and placement of the ceramic sample cup 500.

[0060] A ceramic sample cup 500 is inserted into the heating gap and is positioned above the annular low-voltage electrode 450 to hold the catalytic sample to be tested. The ceramic sample cup 500 includes a main tube 510 inserted into the heating gap. A lower docking cavity 520 is provided on the bottom surface of the main tube 510. The ceramic central tube 420 and the upper section of the cylindrical high-voltage electrode 440 extend into the lower docking cavity 520 for precise alignment.

[0061] A central boss 540 is provided at the top center of the main body 510, and an annular sample cavity 530 is formed around the outer periphery of the central boss 540 for stably placing the catalyst sample to be tested; an overlapping ring 550 is provided on the outer periphery of the top of the main body 510, which is overlapped and fixed to the annular low-pressure electrode 450, ensuring stable assembly, uniform heating, and consistent high-temperature reaction of the sample.

[0062] An external electrode 300 is horizontally mounted on the first side of the main tank 100. The inner end of the external electrode 300 extends into the reaction chamber 130 to assist the electrodes inside the chamber in completing the discharge conduction. The gas interface 150 on the second side can be connected to an external gas supply system to realize the atmosphere replacement inside the chamber and the construction of a controllable atmosphere reaction environment. The electrode lead connector 160 and heating lead connector 170 on the third side are respectively used to lay the electrode circuit and the heating circuit. The circuit is laid through the straight wiring groove 131, the wiring cavity 132, and the ceramic flange wiring hole 412, with neat wiring and safe insulation.

[0063] The main cell 100 is topped with a quartz window 600 to meet the requirements of high-precision in-situ spectral detection. The quartz window 600 is topped with a cover plate 700, which is fixed to the top of the main cell 100 by screws, achieving a tight and sealed fixation of the window. The structure is stable, easy to disassemble and assemble, and facilitates lens replacement and cavity maintenance. A sealing ring groove 140 is provided on the top of the main cell 100, and a rubber sealing ring is embedded in the sealing ring groove 140 to improve the sealing performance of the quartz window 600.

[0064] Working principle and usage process of this invention:

[0065] During the equipment assembly stage, the wiring is first laid out. The heating lead wire and electrode lead wire pass through the heating lead wire connector 170 and electrode lead wire connector 160 respectively, and are laid out through the straight wiring groove 131 and wiring cavity 132. Then they pass through the wiring hole 412 of the ceramic flange base 410 and are respectively connected to the electrical components of the ceramic heating tube 460, cylindrical high voltage electrode 440 and annular low voltage electrode 450. The wiring is neat and has good insulation protection.

[0066] The ceramic flange base 410 is fixedly assembled into the reaction chamber 130 with screws. The ceramic protective sleeve 430 is aligned and placed in the circular groove 411 of the base, completing the concentric assembly of the ceramic heating tube 460. The cylindrical high-voltage electrode 440 is inserted into the ceramic central tube 420. The gap between the ceramic heating tube 460 and the ceramic protective sleeve 430 is filled with heat insulation material to improve the heat insulation performance of the chamber. Then, the annular low-voltage electrode 450 is aligned and covered on the top of the ceramic heating tube 460. The electrodes and heating components are connected to the external high-voltage AC power supply and heating power supply through copper wires.

[0067] The ceramic sample cup 500, which carries the catalyst sample to be tested, is inserted into the heating gap and stably overlapped with the annular low-pressure electrode 450 through the top overlapping ring 550, so that the ceramic central tube 420 and the high-pressure electrode are precisely inserted into the lower docking cavity 520 of the sample cup, and the sample is stably placed inside the sample annular cavity 530.

[0068] After assembly, the quartz window 600 and the top cover plate 700 are sequentially covered and screwed in to seal the cavity. The second side air interface 150 is connected to the external air supply system, and the water-cooled base 200 is connected to the external water chiller at both ends to complete the overall assembly and debugging of the equipment.

[0069] In the formal testing phase, the target gas is first introduced into the reaction chamber 130 through the gas interface 150 to completely replace the air inside the chamber and create the controllable atmosphere required for the experiment. The ceramic heating tube 460 is then activated for resistance heating, which uniformly heats the ceramic sample cup 500 and the sample through heat conduction, with a maximum temperature rise of 500℃, precisely creating a high-temperature catalytic reaction environment.

[0070] According to the required stage, the high-voltage AC power supply is turned on, and a stable and uniform discharge is formed between the cylindrical high-voltage electrode 440 and the annular low-voltage electrode 450, which excites the generation of cold plasma and acts on the sample surface to carry out plasma catalytic reaction.

[0071] Throughout the test, an external water chiller operated continuously, cooling the main tank 100 through the circulating water path of the water-cooled base 200 to suppress temperature rise and protect the equipment structure and peripheral components for stable operation. A Raman detection laser, passing through a high-transmittance quartz window 600, was incident on the sample reaction area, capturing in real-time, in-situ data on changes in the catalyst surface molecular structure, the formation and consumption of reaction intermediates, and the dynamic evolution of active sites, thus completing the dynamic monitoring experiment of the high-temperature plasma catalytic reaction.

[0072] The above embodiments can be applied, by way of example, to the following research:

[0073] Surface reaction kinetics study: Real-time observation of intermediate products, adsorbed species and their dynamic evolution on the catalyst surface under plasma action, providing direct evidence for understanding the reaction pathway.

[0074] Dynamic structural evolution of catalysts: This study investigates the changes in the crystal phase structure and chemical states of active sites (such as metal oxidation states) of catalysts under the combined effects of plasma and high temperature.

[0075] Catalyst deactivation and regeneration mechanisms: In-situ monitoring of catalyst carbonization, sintering or poisoning processes, and investigation of the feasibility and mechanism of in-situ regeneration using plasma methods.

[0076] Pollutant degradation: Investigate the degradation mechanism of volatile organic compounds and greenhouse gases in plasma catalytic reactors, identify key active species and intermediate products, and optimize reactor design.

[0077] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0078] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A cold plasma high-temperature Raman cell, characterized in that, include: The main tank has a reaction chamber in the center. The water-cooled base is flush with the bottom of the main tank. The plasma generator is installed in the middle of the reaction chamber. The plasma generator includes a ceramic flange base, a ceramic central tube fixed in the middle of the surface of the ceramic flange base, and a cylindrical high-voltage electrode inserted inside the ceramic central tube. Ceramic heating tubes are concentrically fitted around the outside of the ceramic central tube, with a heating gap between the ceramic heating tubes and the ceramic central tube. An annular low-voltage electrode is fitted on the outer side of the top of the ceramic heating tube. The gap between the ceramic heating ring and the ceramic protective sleeve is filled with heat insulation material. A ceramic sample cup is inserted into the heating gap and overlaps the annular low-voltage electrode. The ceramic sample cup is positioned by a double-stage system of the ceramic central tube and the ceramic heating tube. The ceramic sample cup includes a main body that is inserted into the heating gap. The bottom surface of the main body has a lower docking cavity. The upper section of the cylindrical high-voltage electrode and the ceramic central tube extend into the lower docking cavity. The top center of the main body has a central boss. The outer periphery of the central boss is a sample ring cavity for storing the sample. The top outer periphery of the main body has an overlapping ring. The external electrode is horizontally installed on the side of the main tank, with its inner end extending into the reaction chamber. Quartz window, which covers the top of the main pool; The cover plate fits over the top of the quartz window and is fixed to the main body by screws.

2. The cold plasma high-temperature Raman cell according to claim 1, characterized in that: The water-cooled base includes a base plate with a mating hole in the middle. A water-cooling ring is provided at the edge of the surface of the base plate. The two ends of the water-cooling ring are symmetrically connected to extension seats, and the ends of the extension seats are connected to water-cooling connectors.

3. The cold plasma high-temperature Raman cell according to claim 2, characterized in that: The bottom surface of the main tank is provided with an assembly ring groove, and the two ends of the assembly ring groove are connected with outward notches. A docking block is provided at the center of the bottom surface of the main tank. The water cooling ring is embedded in the assembly ring groove, the outward seat is embedded in the outward notch, and the docking block is inserted into the mating hole.

4. The cold plasma high-temperature Raman cell according to claim 1, characterized in that: The main pool is rectangular, and its four outer sides are the first side, the second side, the third side and the fourth side. The first side and the third side are arranged opposite each other. An external electrode is installed on the first side, an electrode lead connector and a heating lead connector are provided on the third side, and a gas passage interface is provided on the second side.

5. The cold plasma high-temperature Raman cell according to claim 1, characterized in that: A wiring cavity is provided in the middle of the bottom surface of the reaction chamber, and wiring straight grooves are symmetrically provided at both ends of the wiring cavity, with the two ends of the wiring straight grooves facing the first side and the third side, respectively.

6. The cold plasma high-temperature Raman cell according to claim 1, characterized in that: The ceramic flange base plate has a circular groove on its surface, the inner diameter of which is the same as the outer diameter of the ceramic protective sleeve, and a wiring hole is provided inside the ceramic flange.

7. The cold plasma high-temperature Raman cell according to claim 1, characterized in that: The upper section of the cylindrical high-voltage electrode has a larger outer diameter than the lower section. The upper end of the cylindrical high-voltage electrode is stopped at the top of the ceramic central tube, and the lower section of the cylindrical high-voltage electrode penetrates the ceramic central tube and extends into the wiring cavity.

8. The cold plasma high-temperature Raman cell according to claim 1, characterized in that: The height of the ceramic heating tube is greater than the height of the ceramic center tube. The bottom surface of the annular low-pressure electrode is provided with an annular groove that fits the top of the ceramic heating tube. The inner diameter of the annular low-pressure electrode is the same as the inner diameter of the ceramic heating tube.

9. The cold plasma high-temperature Raman cell according to claim 1, characterized in that: The ceramic protective sleeve has symmetrical openings on its sides for easy removal of the ceramic sample cup.

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