Plasma arc chemical vapor deposition (CVD) apparatus and use thereof

Abstract

This invention belongs to the field of vapor deposition technology, specifically a plasma-arc chemical vapor deposition (CVD) apparatus and its application. It includes a base plate, a support fixedly mounted on top of the base plate, a reaction chamber mounted on the support, an anode graphite crucible fixedly mounted inside the reaction chamber, an anode metal contained inside the anode graphite crucible, an evaporation chamber inside the reaction chamber, a CVD growth chamber inside the reaction chamber, and a hollow graphite cathode fixedly mounted inside the reaction chamber. This plasma-arc chemical vapor deposition (CVD) apparatus and its application utilize a V-shaped connection between the evaporation chamber and the CVD growth chamber. The catalyst generated by the plasma arc evaporating on the anode metal surface is reflected and rapidly enters the CVD growth chamber, avoiding particle growth and deactivation during transport and preventing the significant negative impact of complex carbon source gas in the subsequent CVD chamber on arc stability, thereby improving catalyst utilization and reaction efficiency.

Description

Technical Field

[0001] This invention belongs to the field of vapor deposition technology, specifically a plasma-arc chemical vapor deposition (CVD) device and its application. Background Technology

[0002] Single-walled carbon nanotubes can be viewed as hollow tubular structures formed by a single layer of graphene sheet rolled around a central axis at a certain helical angle. Their diameter is typically only 0.4-2 nanometers, about one fifty-thousandth the diameter of a human hair, but their length can reach several micrometers or even longer. This unique single-atom-layer tubular structure endows single-walled carbon nanotubes with a series of superior properties far exceeding those of conventional materials. Currently, the main methods for preparing single-walled carbon nanotubes include arc discharge, laser ablation, plasma, high-pressure carbon monoxide, and chemical vapor deposition.

[0003] A Chinese patent with announcement number CN110217777A discloses a carbon nanotube preparation device and method. The method uses a high-temperature plasma arc to evaporate an anode composed of a catalyst metal to obtain catalyst nanoparticles, which then react with a carbon source that is simultaneously cracked to obtain single-walled carbon nanotubes.

[0004] This method generates extremely high temperatures at the anolyte surface due to the plasma arc, resulting in catalyst evaporation far exceeding actual requirements. Furthermore, the catalyst collidees and aggregates into large, ineffective particles, leaving a significant amount of catalyst residue in the product and leading to low product purity. Simultaneously, the complex gas flow and composition make the plasma arc highly unstable, severely affecting the uniformity of the temperature field in the reaction region and resulting in low utilization of the catalyst and carbon source. Therefore, achieving both high efficiency and high product quality in the preparation of single-walled carbon nanotubes remains a significant challenge.

[0005] Therefore, the present invention provides a plasma arc chemical vapor deposition (CVD) apparatus and its application. Summary of the Invention

[0006] To overcome the shortcomings of existing technologies and solve the problem of low utilization of catalysts and carbon sources, this invention proposes a plasma arc chemical vapor deposition (CVD) device and its application.

[0007] The technical solution adopted by the present invention to solve its technical problem is as follows: A plasma arc chemical vapor deposition (CVD) device of the present invention includes a base plate, a support fixedly mounted on the top of the base plate, a reaction chamber mounted on the support, an anode graphite crucible fixedly mounted inside the reaction chamber, an anode metal disposed inside the anode graphite crucible, an evaporation chamber disposed inside the reaction chamber, a CVD growth chamber disposed inside the reaction chamber, and the evaporation chamber and the CVD growth chamber are connected in a V-shape, a hollow graphite cathode fixedly mounted inside the reaction chamber, with the end of the hollow graphite cathode located above the anode graphite crucible, a carbon source gas channel disposed on the reaction chamber and connected to the CVD growth chamber, an array of electric heating coils disposed on the CVD growth chamber, an exhaust pipe connected to the CVD growth chamber, a slag discharge pipe disposed inside the reaction chamber and connected to the evaporation chamber, and a cooling component disposed inside the exhaust pipe; A feeding mechanism is provided on the base plate, a filter is fixedly installed on the reaction tank, a connecting pipe is connected to the bottom end of the filter, and the other end of the connecting pipe is connected to the end of the exhaust pipe. A screening mechanism is provided inside the filter.

[0008] Preferably, the cooling assembly includes a cooling chamber and a heat absorption pipe. The cooling chamber is disposed inside the exhaust pipe, and the heat absorption pipe is arranged around the exhaust pipe. An opening and closing door is provided on the side of the reaction chamber. A connector is connected to the side of the hollow graphite cathode. A seamless gas cylinder is fixedly disposed on the base plate, and the output end of the seamless gas cylinder is connected to the connector through a pipe.

[0009] Preferably, the feeding mechanism includes a static mixer and a gas storage tank. The static mixer is mounted on the base plate, and the output end of the static mixer is connected to the carbon source gas channel through a pipe. The array of gas storage tanks for storing carbon source gas is mounted on the base plate, and the output end of the gas storage tanks is connected to the input end of the static mixer through a pipe. The feeding mechanism also includes a rotating component, a support frame, a storage tank, a discharge pipe, and a mixing component. The rotating component is mounted on a base plate, the support frame is mounted on the rotating component, an array of storage tanks for storing catalysts and co-catalysts is mounted on the support frame, the discharge pipe is mounted below the storage tanks, and the mixing component is mounted below the storage tanks and is connected to the hollow graphite cathode.

[0010] Preferably, the rotating assembly includes a frame, a load-bearing frame, a reducer, a servo motor, and a drive shaft. The frame is fixed to the base plate, the load-bearing frame is fixed to the top of the frame, the reducer is fixed inside the frame, the servo motor is fixed inside the frame, and the output end of the servo motor is fixedly connected to the input end of the reducer. The drive shaft is rotatably disposed inside the load-bearing frame, and one end of the drive shaft is fixedly connected to the output end of the reducer, while the other end of the drive shaft is fixedly connected to the center position of the support frame. A drive wheel is fixedly disposed on the drive shaft, and a load-bearing plate is fixedly disposed on the load-bearing frame. The mixing assembly includes a mixing tank, a rotating shaft, and stirring blades. The mixing tank is fixed to a load-bearing plate. The rotating shaft is rotatably disposed inside the mixing tank. An array of stirring blades is disposed on the mixing tank. A transmission groove is fixedly disposed on the load-bearing plate, with one end of the transmission groove extending into the interior of the mixing tank. One end of the rotating shaft extends into the transmission groove. A driven wheel is fixedly disposed at the top of the rotating shaft. A transmission rod is disposed inside the transmission groove, and a first rotating wheel is fixedly connected to the top of the transmission rod. The first rotating wheel and the driven wheel are connected by a belt drive. A second rotating wheel is fixedly disposed on the transmission rod. The load-bearing plate is hollow. The second rotating wheel and the drive wheel are connected by a belt drive. A drive block is fixedly disposed on the second rotating wheel.

[0011] Preferably, a vibration frame is fixedly installed inside the load-bearing plate, a striking block is installed inside the vibration frame, a first spring is fixedly installed inside the vibration frame, and one end of the first spring is fixedly connected to the striking block. A pressure plate is fixedly connected to the striking block, and the pressure plate is located on one side of the second rotating wheel.

[0012] Preferably, a nozzle is fixedly installed inside the filter, and the nozzle is connected to the end of the heat absorption tube through a pipe. A conical groove is fixedly installed inside the filter.

[0013] Preferably, the screening mechanism includes a square frame, a ventilation slot, a storage slot, a frame body, and filter cartridges. The square frame is fixed inside the filter and is located on one side of the conical slot. The ventilation slot is located on the top of the square frame and is connected to one end of the conical slot. The storage slot array is located inside the square frame. The frame body is located inside the storage slot. The filter cartridge array is located inside the frame body. The frame has a sliding groove inside, and a baffle is installed inside the sliding groove. The baffle is located on one side of the filter cartridge. A push rod is fixedly installed on the top of the baffle. A return spring is fixedly installed inside the baffle. A limiting plate is fixedly installed inside the sliding groove and passes through the baffle. One end of the return spring is fixedly connected to the limiting plate.

[0014] Preferably, the storage slot has a movable slot on its side, a power motor is fixedly installed inside the movable slot, a threaded screw is fixedly connected to the output end of the power motor, the end of the threaded screw is rotatably connected to the inside of the movable slot, a corrugated tube is sleeved on the threaded screw to protect the surface of the threaded screw, a sliding block is installed inside the movable slot, and the threaded screw is threadedly connected to the inside of the sliding block, an electromagnet is fixedly installed on the side of the sliding block, and the electromagnet is located on one side of the frame, and a guide shaft is fixedly installed inside the movable slot, and the guide shaft passes through the sliding block.

[0015] Preferably, a wind box is fixedly installed on the side of the frame, a fan is fixedly installed inside the wind box, a third impeller is fixedly installed inside the fan, a fourth impeller is fixedly installed on the drive shaft, and the fourth impeller and the third impeller are connected by belt drive. The output end of the fan is connected to the end of the heat absorption pipe through a pipe.

[0016] A method for using a plasma-arc chemical vapor deposition (CVD) apparatus includes the following steps: S1. Plasma gas is introduced into the hollow graphite cathode to ignite an electric arc between it and the graphite crucible containing the anode metal. The evaporation chamber is preheated to the specified temperature to melt the anode metal. At the same time, the slag outlet of the slag discharge pipe is opened to discharge the generated metal slag particles. S2. Turn on the CVD growth chamber heating and raise the temperature to the growth temperature through the electric heating coil. At this time, close the slag discharge outlet. S3. Start the feeding mechanism to send the catalyst and co-catalyst into the evaporation chamber through the hollow graphite cathode, generating a catalyst mixture, which quickly enters the CVD growth chamber under the reflection of the V-shaped structure. S4. A mixture of carrier gas and carbon source is introduced through the carbon source gas channel, and reacts with the catalyst mixture in the CVD growth chamber. After cooling, the mixture is collected at the tail gas outlet to obtain the final product.

[0017] The beneficial effects of this invention are as follows: 1. The plasma-arc chemical vapor deposition (CVD) apparatus and its application described in this invention, through a V-shaped connection between the evaporation chamber and the CVD growth chamber, allows the catalyst generated by the plasma arc evaporation on the anode metal surface to quickly enter the CVD growth chamber after reflection, avoiding particle growth and deactivation during transport, and avoiding the significant negative impact of complex carbon source gas in the subsequent CVD chamber on arc stability, thus solving the key problem of plasma arc stability. The diameter of the evaporation chamber increases after transitioning to the CVD growth chamber, reducing the gas flow linear velocity in the CVD growth chamber, thereby extending the residence time of the catalyst and carbon source in the CVD growth chamber, improving catalyst utilization and reaction efficiency, and thus increasing yield. The carbon source inlet direction forms a counter-angle with the catalyst entering the CVD growth chamber, improving the mixing efficiency of the carbon source and catalyst, thereby improving the efficiency of subsequent catalytic growth.

[0018] 2. The plasma-arc chemical vapor deposition (CVD) apparatus and its application described in this invention, by configuring a filter cartridge and a frame, can efficiently collect and sort products. After the frame extends into the ventilation channel, it can block the transverse cross-section of the ventilation channel, so that the exhaust gas carrying the product can only flow directionally into the filter cartridge. After being screened and separated by the filter cartridge, the product is trapped and stored in the inner cavity of the filter cartridge, while the exhaust gas flows out from the other side of the filter cartridge. It can be connected to an external exhaust gas treatment device for purification before being discharged. When the product collection in the filter cartridge is saturated, one side of the frame can be controlled to be lifted upwards. Before the frame is fully inserted into the ventilation channel, it is pushed upwards. The rod first abuts against the top of the inner wall of the ventilation slot and moves downward, thereby pushing the baffle down to release the blockage at the end of the filter cartridge. At the same time, it controls the frame on the other side that carries the screening to move downward. During the downward movement of the frame, the return spring rebounds, driving the baffle and push rod to return to their original positions and re-close the end of the filter cartridge. This can effectively prevent the collected product from accidentally spilling. The frame can be disassembled and replaced, making it easy to replace the full filter cartridge and transfer the product. By repeating the above switching process, continuous screening and product collection can be achieved without stopping the machine, ensuring the continuous working efficiency of the equipment and avoiding the loss of production capacity caused by stopping the machine to replace the filter cartridge.

[0019] 3. The plasma arc chemical vapor deposition (CVD) apparatus and its application described in this invention, by setting up a mixing tank and a storage tank, can realize the preparation of multiple catalysts by mixing them in proportion, improving the flexibility of equipment use. It can be flexibly adjusted according to the embedding ratio requirements. The support frame can drive the storage tank to rotate, rotating the storage tank containing the corresponding catalyst to directly above the mixing tank. By controlling the opening and closing of the discharge pipe, the catalyst is sent into the mixing tank. When the drive shaft rotates, it drives the second rotating wheel to rotate through the drive wheel. The second rotating wheel drives the first rotating wheel and the driven wheel to rotate synchronously through the transmission rod, thereby driving the rotating shaft and stirring blades to rotate. The stirring blades stir and mix the catalyst in the mixing tank, ensuring that the catalyst is fully and evenly mixed to meet the requirements of subsequent reactions, effectively improving the efficiency of mixing and preparation.

[0020] 4. The plasma arc chemical vapor deposition (CVD) apparatus and its application described in this invention facilitate smooth catalyst feeding by setting up a vibrating frame. When the second rotor rotates, it drives the drive block to rotate synchronously. When the drive block rotates to the side of the pressure plate and applies pressure, it pushes the striking block to form displacement. After the drive block rotates past and releases pressure, the first spring elastically resets and drives the striking block back to its position. The reciprocating motion of the striking block collides with the vibrating frame to generate vibration. The vibration is transmitted to the mixing tank through the load-bearing plate, causing the mixing tank to vibrate, thereby promoting the rapid falling of the catalyst, avoiding material accumulation and blockage, ensuring smooth and efficient feeding, and guaranteeing work efficiency. Attached Figure Description

[0021] The invention will now be further described with reference to the accompanying drawings.

[0022] Figure 1 This is a perspective view of the plasma arc chemical vapor deposition (CVD) apparatus of the present invention; Figure 2 This is a schematic diagram of the structure of the storage tank and the seamless gas cylinder in this invention; Figure 3 This is a schematic diagram of the connection between the load-bearing frame and the mixing tank in this invention; Figure 4 This is a schematic diagram of the mixing tank in this invention; Figure 5 This is a schematic diagram of the structure of the rotating shaft and stirring blade in this invention; Figure 6 This is a schematic diagram of the hollow graphite cathode and carbon source gas channel in this invention; Figure 7 This is a schematic diagram of the reaction chamber in this invention; Figure 8 This is a structural schematic diagram of the frame and load-bearing frame in this invention; Figure 9 This is a schematic diagram of the structure of the load-bearing plate and the vibration frame in this invention; Figure 10 This is a schematic diagram of the structure of the bellows in this invention; Figure 11 This is a schematic diagram of the filter structure in this invention; Figure 12 This is a schematic diagram of the structure of the storage slot in this invention; Figure 13 This is a schematic diagram of the frame and square frame in this invention; Figure 14 This is a schematic diagram of the structure of the nozzle and the conical groove in this invention; Figure 15 This is a schematic diagram of the structure of the storage slot and the frame in this invention; Figure 16 This is the Raman spectrum of the carbon nanotubes prepared in this invention; Figure 17 These are scanning electron microscope images of the carbon nanotubes prepared in this invention; Figure 18 This is a transmission electron microscope image of the carbon nanotubes prepared in this invention.

[0023] In the diagram: 1. Base plate; 2. Support frame; 3. Reaction chamber; 4. Anode graphite crucible; 5. Anode metal; 6. Hollow graphite cathode; 7. Evaporation chamber; 8. Slag discharge pipe; 9. CVD growth chamber; 10. Carbon source gas channel; 11. Exhaust pipe; 12. Electric heating coil; 13. Cooling chamber; 14. Opening door; 15. Static mixer; 16. Gas storage tank; 17. Frame; 18. Load-bearing frame; 19. Reducer; 20. Servo motor; 21. Drive shaft; 22. Drive wheel; 23. Support frame; 24. Storage tank; 25. Discharge pipe; 26. Load-bearing plate; 27. Mixing tank; 28. Transmission groove; 29. ​​Rotating shaft; 30. Stirring blade; 31. Driven wheel; 32. No. 1 rotor; 33. 34. Transmission rod; 35. Second rotating wheel; 36. Drive block; 37. Vibration frame; 38. Striking block; 39. Pressure plate; 40. First spring; 41. Heat absorption pipe; 42. Filter; 43. Connecting pipe; 44. Nozzle; 45. Conical groove; 46. Square frame; 47. Ventilation groove; 48. Storage groove; 49. Frame body; 50. Filter cartridge; 51. Slide groove; 52. Baffle; 53. Push rod; 54. Return spring; 55. Limiting plate; 56. Movable groove; 57. Power motor; 58. Threaded screw; 59. Sliding block; 60. Guide shaft; 61. Electromagnet; 62. Air box; 63. Fan; 64. Third rotating wheel; 65. Connector; 66. Seamless gas cylinder; 67. Fourth rotating wheel. Detailed Implementation

[0024] To make the technical means, creative features, objectives and effects of this invention easier to understand, the invention will be further described below in conjunction with specific embodiments.

[0025] Example 1

[0026] use Figure 6 and Figure 7 The apparatus shown is used for the growth of single-walled carbon nanotubes. The plasma is a DC-transferred arc plasma with a power of 150 kW, a current of 1500 A, and a voltage of 100 V. The evaporation chamber 7 and the CVD growth chamber 9 are connected in a V-shape at an angle of 90°. The diameter ratio of the evaporation chamber 7 and the CVD growth chamber 9 is 1:2. The bottom of the connection is an anode graphite crucible 4. The carbon source inlet is at a 45° angle to the CVD growth chamber 9.

[0027] Preparation process: Argon is used as the plasma arc gas. The plasma gas is introduced into the hollow graphite cathode 6 and an arc is ignited between it and the anode graphite crucible 4 containing the first catalyst metal (Fe40%-Mo60% alloy). The evaporation chamber 7 is preheated to 1500℃ for melting, and the slag outlet is opened to discharge the generated metal slag particles. The CVD growth chamber 9 is heated to 1200℃, at which point the slag outlet is closed. The feeding mechanism is opened, and ferrocene and thiophene in a mass ratio of 10:1 are fed into the evaporation chamber 7 through the hollow graphite cathode 6 to generate a catalyst mixture. Under the reflection of the V-shaped structure, the mixture quickly enters the CVD growth chamber 9. A mixture of argon, hydrogen, water vapor, and methane is introduced through the carbon source gas inlet channel. The mixture reacts with the catalyst mixture in the CVD growth chamber 9. After cooling, the final product is collected at the tail gas outlet with the gas flow. The total gas flow rate of the reaction system is 200 L / min, including 80% Ar, 10% H2, 7% methane, and 3% water.

[0028] The degree of crystallization of the product was characterized by Raman spectroscopy. Figure 16 The Raman spectral characterization results show that the peaks near 1250 cm⁻¹ and 1550 cm⁻¹ correspond to the D and G peaks, respectively. The G peak represents the degree of graphitization and crystallinity, while the D peak represents the non-graphitized structure. Therefore, the ratio of the two peak intensities, i.e., the IG / ID ratio, can be used to qualitatively determine the degree of graphitization and crystallinity of carbon nanotubes. Figure 16 The IG / ID ratio shown is ~120. The morphology was observed using scanning electron microscopy (SEM), as follows... Figure 17 The image shown is its SEM image; its structure was observed and analyzed using transmission electron microscopy (TEM), such as... Figure 18 The TEM image shown reveals single-walled and few-walled carbon nanotubes. After 4 hours of continuous operation, the hourly yield was recorded, and samples were calcined at 800 °C for 4 hours. The ash content was measured, and the carbon purity was calculated. The Raman spectroscopy results, G / D ratio, purity, and yield of the products are summarized in Table 1.

[0029] Example 2

[0030] use Figure 6 and Figure 7 The apparatus shown is used for the growth of single-walled carbon nanotubes. The plasma is a DC transferred arc plasma with a power of 50 kW, a current of 100 A, and a voltage of 50 V. The evaporation chamber 7 and the CVD growth chamber 9 are connected in a V-shape at an angle of 120°. The diameter ratio of the evaporation chamber 7 and the CVD growth chamber 9 is 1:1.5. The bottom of the connection is an anode graphite crucible 4. The carbon source inlet is at a 30° angle to the CVD growth chamber 9.

[0031] Preparation process: Argon is used as the plasma arc gas. The plasma gas is introduced into the hollow graphite cathode 6 and an arc is ignited between it and the anode graphite crucible 4 containing the first catalyst metal (Fe). The evaporation chamber 7 is preheated to 1400℃ for melting, and the slag discharge port is opened to discharge the generated metal slag particles. The CVD growth chamber 9 is heated to 900℃, and the slag discharge port is closed. The feeding mechanism is opened, and ferrocene and thiophene in a mass ratio of 10:1 are fed into the evaporation chamber 7 through the hollow graphite cathode 6 to generate a catalyst mixture. Under the reflection of the V-shaped structure, the mixture quickly enters the CVD growth chamber 9. Argon, hydrogen, water vapor and methane mixture are introduced through the carbon source gas inlet channel and react with the catalyst mixture in the CVD growth chamber 9. After cooling, the mixture is collected at the tail gas outlet to obtain the final product. The total gas flow rate of the reaction system is 100 L / min, of which Ar 55%, H2 25%, methane 15% and water 5%.

[0032] The G / D ratio, purity, and yield of the products were summarized in Table 1 using Raman spectroscopy.

[0033] Example 3

[0034] use Figure 6 and Figure 7 The apparatus shown is used for the growth of single-walled carbon nanotubes. The plasma is a DC transferred arc plasma with a power of 1000 kW, a current of 10000 A, and a voltage of 100 V. The evaporation chamber 7 and the CVD growth chamber 9 are connected in a V-shape at an angle of 90°. The diameter ratio of the evaporation chamber 7 and the CVD growth chamber 9 is 1:5. The bottom of the connection is an anode graphite crucible 4. The carbon source inlet is at a 60° angle to the CVD growth chamber 9.

[0035] Preparation process: Argon is used as the plasma arc gas. The plasma gas is introduced into the hollow graphite cathode 6 and an arc is ignited between it and the anode graphite crucible 4 containing the first catalyst metal (Fe 40%-Ta 60%). The evaporation chamber 7 is preheated to 1800℃ for melting, and the slag outlet is opened to discharge the generated metal slag particles. The CVD growth chamber 9 is heated to 1400℃, at which point the slag outlet is closed. The feeding mechanism is opened, and iron acetylacetonate and sulfur powder in a mass ratio of 5:1 are fed into the evaporation chamber 7 through the hollow graphite cathode 6 to generate a catalyst mixture. Under the reflection of the V-shaped structure, the mixture quickly enters the CVD growth chamber 9. Argon, hydrogen, water vapor and methane mixture are introduced through the carbon source gas inlet channel and react with the catalyst mixture in the CVD growth chamber 9. After cooling, the mixture is collected at the tail gas outlet to obtain the final product. The total gas flow rate of the reaction system is 750 L / min, of which Ar 55%, H2 15%, methane 25% and water 5%.

[0036] The G / D ratio, purity, and yield of the products were summarized in Table 1 using Raman spectroscopy.

[0037] Example 4

[0038] use Figure 6 and Figure 7 The apparatus shown is used for the growth of single-walled carbon nanotubes. The plasma is a DC-transferred arc plasma with a power of 150 kW, a current of 1500 A, and a voltage of 100 V. The evaporation chamber 7 and the CVD growth chamber 9 are connected in a V-shape at an angle of 90°. The diameter ratio of the evaporation chamber 7 and the CVD growth chamber 9 is 1:2. The bottom of the connection is an anode graphite crucible 4. The carbon source inlet is at a 45° angle to the CVD growth chamber 9.

[0039] Preparation process: Argon is used as the plasma arc gas. The plasma gas is introduced into the hollow graphite cathode 6 and an arc is ignited between it and the anode graphite crucible 4 containing the first catalyst metal (metal Co). The evaporation chamber 7 is preheated to 1300℃ for melting, and the slag discharge port is opened to discharge the generated metal slag particles. The CVD growth chamber 9 is heated to 1200℃, at which point the slag discharge port is closed. The feeding mechanism is opened, and iron acetylacetone and selenium powder with a mass ratio of 25:1 are fed into the evaporation chamber 7 through the hollow graphite cathode 6 to generate a catalyst mixture. Under the reflection of the V-shaped structure, the mixture quickly enters the CVD growth chamber 9. Argon, hydrogen, water vapor and methane mixture are introduced through the carbon source gas inlet channel and react with the catalyst mixture in the CVD growth chamber 9. After cooling, the mixture is collected at the tail gas outlet to obtain the final product. The total gas flow rate of the reaction system is 300 L / min, of which Ar 75%, H2 10%, methane 10% and water 5%.

[0040] The G / D ratio, purity, and yield of the products were summarized in Table 1 using Raman spectroscopy.

[0041] The data for each embodiment are summarized in Table 1.

[0042] Table 1

[0043] As can be seen from the above data summary, the carbon nanotube products of the embodiments of the present invention are mainly single-walled and few-walled carbon nanotubes, with significant improvements in growth efficiency, purity and quality, and have great industrialization prospects.

[0044] Example 5

[0045] like Figures 1 to 18As shown in the embodiment of the present invention, a plasma arc chemical vapor deposition (CVD) apparatus includes a base plate 1, a support 2 fixedly mounted on the top of the base plate 1, a reaction chamber 3 mounted on the support 2, an anode graphite crucible 4 fixedly mounted inside the reaction chamber 3, an anode metal 5 disposed inside the anode graphite crucible 4, an evaporation chamber 7 disposed inside the reaction chamber 3, and a CVD growth chamber 9 disposed inside the reaction chamber 3, with the evaporation chamber 7 and the CVD growth chamber 9 connected in a V-shape. A hollow graphite cathode 6 is fixedly mounted inside the reaction chamber 3, with its end positioned above the anode graphite crucible 4. The reaction chamber 3 is equipped with a carbon source gas channel 10, which is connected to the CVD growth chamber 9. The CVD growth chamber 9 is equipped with an array of electric heating coils 12. The CVD growth chamber 9 is also connected to an exhaust pipe 11. The reaction chamber 3 is equipped with a slag discharge pipe 8, which is connected to the evaporation chamber 7. The exhaust pipe 11 is equipped with a cooling component. The bottom plate 1 is equipped with a feeding mechanism. The reaction chamber 3 is fixedly equipped with a filter 41. The bottom end of the filter 41 is connected to a connecting pipe 42, and the other end of the connecting pipe 42 is connected to the end of the exhaust pipe 11. The filter 41 is equipped with a screening mechanism. An external controller is connected to the electronic equipment on the plasma-arc chemical vapor deposition (CVD) device. The controller can control the operation of the plasma-arc chemical vapor deposition (CVD) device when preparing carbon nanotubes using the plasma-arc chemical vapor deposition (CVD) device. The plasma gas stored inside the seamless gas cylinder 66 can be any one, two or three of nitrogen, argon, helium and hydrogen in any proportion, with a flow rate of 50 L / min to 500 L / min. The anode metal 5 can be iron, cobalt, nickel, or mixtures thereof, or alloys or mixtures of iron, cobalt, nickel, and refractory metals. The refractory metal element can be molybdenum, tungsten, tantalum, niobium, hafnium, zirconium, etc., with a weight percentage of 50%–80%. The evaporation chamber 7 temperature is 1400–1800 ℃, and the CVD growth temperature is 900–1400 ℃. The storage tank 24 can store a second catalyst and a co-catalyst. The second catalyst is any one of ferrocene, cobalt cerone, iron carbonyl, iron acetylacetonate, cobalt acetylacetonate, nickel acetylacetonate, or a mixture thereof. The co-catalyst can be any one of sulfur powder, selenium powder, thiophene, carbon disulfide, or hydrogen sulfide. The ratio of catalyst to co-catalyst is 1:1 to 50:1. The plasma is a DC transferred arc plasma with a power of 50~1000 kW, a current of 100~10000 A, and a voltage of 10~150 V.

[0046] The evaporation chamber 7 and the CVD growth chamber 9 are connected in a V-shape with an angle of 45-120°, and the diameter ratio of the evaporation chamber 7 and the CVD growth chamber 9 is 1:1.5 to 1:5. The bottom of the connection is the anode graphite crucible 4, and the air inlet of the carbon source gas channel 10 is at an angle of 30-60° to the CVD growth chamber 9. Plasma gas is introduced into the hollow graphite cathode 6, and an electric arc is ignited between it and the anode graphite crucible 4 containing the anode metal 5. The evaporation chamber 7 is preheated to a specified temperature to melt the anode metal 5. At the same time, the slag discharge port of the slag discharge pipe 8 is opened to discharge the generated metal slag particles. The CVD growth chamber 9 is heated and the temperature is raised to the growth temperature by the electric heating coil 12. At this time, the slag discharge port is closed and the feeding mechanism is opened to send the catalyst and co-catalyst from the hollow graphite cathode 6 into the evaporation chamber 7 to generate a catalyst mixture. Under the reflection of the V-shaped structure, the mixture of carrier gas and carbon source is introduced through the carbon source gas channel 10 and reacts with the catalyst mixture in the CVD growth chamber 9. After cooling, the mixture flows with the gas flow and is collected by the screening mechanism to obtain the final product. The electric heating coil 12 can raise and regulate the internal temperature of the CVD growth chamber 9, and the cooling component can cool the airflow entering the exhaust pipe 11. Solenoid valves are installed on the pipelines that transport the medium in plasma-arc chemical vapor deposition (CVD) equipment to control the opening and closing of the pipelines.

[0047] Furthermore, the cooling assembly includes a cooling chamber 13 and a heat absorption pipe 40. The cooling chamber 13 is located inside the exhaust pipe 11, and the heat absorption pipe 40 is arranged around the exhaust pipe 11. An opening and closing door 14 is provided on the side of the reaction chamber 3. A connector 65 is connected to the side of the hollow graphite cathode 6. A seamless gas cylinder 66 is fixedly installed on the base plate 1, and the output end of the seamless gas cylinder 66 is connected to the connector 65 through a pipe. The product begins to react with the catalyst mixture in the CVD growth chamber 9. The gas flow carries the product into the cooling chamber 13, where the heat can be absorbed and dissipated through the heat absorption pipe 40. The opening and closing door 14 can be opened and closed. After the opening and closing door 14 is opened, it is convenient to place or replace the anode metal 5 (first catalyst metal) into the anode graphite crucible 4. The plasma gas stored inside the seamless gas cylinder 66 can be any one, two or three of nitrogen, argon, helium and hydrogen in any mixture ratio, with a flow rate of 50 L / min to 500 L / min.

[0048] Furthermore, the feeding mechanism includes a static mixer 15 and a gas storage tank 16. The static mixer 15 is mounted on the base plate 1, and the output end of the static mixer 15 is connected to the carbon source gas channel 10 through a pipe. The array of gas storage tanks 16 for storing carbon source gas is mounted on the base plate 1, and the output end of the gas storage tank 16 is connected to the input end of the static mixer 15 through a pipe. The feeding mechanism also includes a rotating component, a support frame 23, a storage tank 24, a discharge pipe 25, and a mixing component. The rotating component is mounted on the base plate 1, the support frame 23 is mounted on the rotating component, the array of storage tanks 24 for storing catalysts and co-catalysts is mounted on the support frame 23, the discharge pipe 25 is mounted below the storage tanks 24, and the mixing component is mounted below the storage tanks 24 and is connected to the hollow graphite cathode 6. The carbon source gas can be any one of methane, ethane, propane, ethylene, propylene, acetylene, natural gas, etc., and the carrier gas can be any one or a combination of nitrogen, argon, helium, and hydrogen. In the mixture formed by the plasma arc gas, the feeding carrier gas and the carbon source carrier gas, the carbon source gas is 5%-25%, the inert gas is 60%-85%, the hydrogen is 5%-25%, the water is 1%-5%, and the total flow rate is 100-750 L / min. When the carbon source gas enters the static mixer 15, it can be mixed and flowed. The mixed gas can flow into the carbon source gas channel 10 and enter the CVD growth chamber 9 through the carbon source gas channel 10. It will then react with the catalyst mixture in the CVD growth chamber 9. When multiple catalysts are added, the catalyst stored in the storage tank 24 can be added into the mixing component through the discharge pipe 25 to mix the catalyst. This allows for easy adjustment of the catalyst ratio according to actual needs. The discharge pipe 25 is equipped with a solenoid valve.

[0049] Furthermore, the rotating assembly includes a frame 17, a load-bearing frame 18, a reducer 19, a servo motor 20, and a drive shaft 21. The frame 17 is fixed on the base plate 1, the load-bearing frame 18 is fixed on the top of the frame 17, the reducer 19 is fixed inside the frame 17, the servo motor 20 is fixed inside the frame 17, and the output end of the servo motor 20 is fixedly connected to the input end of the reducer 19. The drive shaft 21 is rotatably disposed inside the load-bearing frame 18, and one end of the drive shaft 21 is fixedly connected to the output end of the reducer 19, while the other end of the drive shaft 21 is fixedly connected to the center position of the support frame 23. A drive wheel 22 is fixedly disposed on the drive shaft 21, and a load-bearing plate 26 is fixedly disposed on the load-bearing frame 18. The mixing assembly includes a mixing tank 27, a rotating shaft 29, and stirring blades 30. The mixing tank 27 is fixed on a load-bearing plate 26. The rotating shaft 29 is rotatably disposed inside the mixing tank 27. The stirring blades 30 are arranged in an array on the mixing tank 27. A transmission groove 28 is fixedly disposed on the load-bearing plate 26, and one end of the transmission groove 28 extends into the mixing tank 27. One end of the rotating shaft 29 extends into the transmission groove 28. A driven wheel 31 is fixedly disposed at the top of the rotating shaft 29. A transmission rod 33 is disposed inside the transmission groove 28. A first rotating wheel 32 is fixedly connected to the top of the transmission rod 33. The first rotating wheel 32 and the driven wheel 31 are connected by a belt drive. A second rotating wheel 34 is fixedly disposed on the transmission rod 33. The load-bearing plate 26 is hollow. The second rotating wheel 34 and the drive wheel 22 are connected by a belt drive. A drive block 35 is fixedly disposed on the second rotating wheel 34. The operation of the servo motor 20 drives the reducer 19 to move. When the reducer 19 moves, it drives the drive shaft 21 to rotate. The rotation of the drive shaft 21 drives the support frame 23 to rotate, which in turn drives the storage tank 24 to rotate. This causes the storage tank 24, which contains different catalysts, to rotate directly above the mixing tank 27. By controlling the opening and closing of the discharge pipe 25, the catalyst can be added into the mixing tank 27. When the drive shaft 21 rotates, it drives the second rotating wheel 34 to rotate through the drive wheel 22. The rotation of the second rotating wheel 34 drives the transmission rod 33 to rotate, which in turn drives the rotating shaft 29 to rotate through the first rotating wheel 32 and the driven wheel 31. The rotation of the rotating shaft 29 drives the stirring blade 30 to rotate. The rotation of the stirring blade 30 mixes the catalyst that has entered the mixing tank 27, ensuring that the catalyst is fully mixed and facilitating subsequent reactions.

[0050] Furthermore, a vibrating frame 36 is fixedly installed inside the load-bearing plate 26, a striking block 37 is installed inside the vibrating frame 36, a first spring 39 is fixedly installed inside the vibrating frame 36, and one end of the first spring 39 is fixedly connected to the striking block 37. A pressure plate 38 is fixedly connected to the striking block 37, and the pressure plate 38 is located on one side of the second rotating wheel 34. When the second rotating wheel 34 rotates, it drives the driving block 35 to rotate. When the driving block 35 rotates and contacts the pressure plate 38, it pushes the striking block 37 to move. When the pressure is no longer applied, the first spring 39 resets and pushes the striking block 37 to reset. The striking block 37 collides with the vibrating frame 36 to generate vibration, which causes the load-bearing plate 26 to vibrate. This vibration can then be transmitted to the mixing tank 27. The vibration of the mixing tank 27 facilitates the rapid feeding of the catalyst.

[0051] Furthermore, a nozzle 43 is fixedly installed inside the filter 41, and the nozzle 43 is connected to the end of the heat absorption tube 40 through a pipe. A conical groove 44 is fixedly installed inside the filter 41. After the airflow absorbs heat inside the heat absorption pipe 40, the airflow will enter the nozzle 43 through the pipe. The nozzle 43 will cause the airflow to flow inside the filter 41. The exhaust gas carrying the prepared product enters the filter 41 through the connecting pipe 42. The airflow can assist the product and exhaust gas flow. After being collected by the conical groove 44, the exhaust gas can be directed to the screening mechanism to screen the product.

[0052] Furthermore, the screening mechanism includes a square frame 45, a ventilation slot 46, a storage slot 47, a frame body 48, and filter cartridges 49. The square frame 45 is fixed inside the filter 41 and is located on one side of the conical slot 44. The ventilation slot 46 is located on the top of the square frame 45, and the conical slot 44 is connected to one end of the ventilation slot 46. The storage slots 47 are arranged in an array inside the square frame 45. The frame body 48 is arranged inside the storage slots 47. The filter cartridges 49 are arranged in an array inside the frame body 48. The frame 48 has a sliding groove 50 inside, and a baffle 51 is installed inside the sliding groove 50. The baffle 51 is located on one side of the filter cartridge 49. A push rod 52 is fixedly installed on the top of the baffle 51. A return spring 53 is fixedly installed inside the baffle 51. A limiting plate 54 is fixedly installed inside the sliding groove 50 and passes through the baffle 51. One end of the return spring 53 is fixedly connected to the limiting plate 54. The exhaust gas and product flow through the conical groove 44 into the ventilation duct 46. Three sets of frames 48 are provided. The first frame 48 closest to the conical groove 44 passes through the ventilation duct 46. After entering the ventilation duct 46, the frame 48 intercepts the transverse section of the ventilation duct 46, allowing the exhaust gas carrying the product to flow only into the filter cartridge 49. The filter cartridge 49 separates the product from the exhaust gas, storing the product inside. The exhaust gas then flows to the outside through the other side of the filter 41. The other end of the filter 41 can be connected to exhaust gas treatment equipment. When the filter cartridge 49 contains too much product, one side of the frame 48 can be moved upwards, allowing it to enter the ventilation duct 46. Before the frame 48 fully enters the ventilation slot 46, the push rod 52 will first contact the top of the inner wall of the ventilation slot 46. The push rod 52 moves down, which will push the baffle 51 down. After the baffle 51 moves down, it will no longer block one side of the filter cylinder 49. At the same time, the frame 48 controlling the screening of products moves down. When the frame 48 moves down, the return spring 53 returns to its original position, which will push the baffle 51 and the push rod 52 to their original positions. The baffle 51 will block the end of the filter cylinder 49, which can effectively prevent the stored products from falling accidentally. The frame 48 can also be disassembled and replaced, which is convenient for storing the stored products. The above steps can be repeated to screen and store products without stopping the machine, ensuring work efficiency and avoiding production capacity loss caused by downtime.

[0053] Furthermore, a movable groove 55 is provided on the side of the storage slot 47. A power motor 56 is fixedly installed inside the movable groove 55. A threaded screw 57 is fixedly connected to the output end of the power motor 56. The end of the threaded screw 57 is rotatably connected to the inside of the movable groove 55. A corrugated tube is sleeved on the threaded screw 57 to protect the surface of the threaded screw 57. A sliding block 58 is provided inside the movable groove 55, and the threaded screw 57 is threadedly connected to the sliding block 58. An electromagnet 60 is fixedly installed on the side of the sliding block 58, and the electromagnet 60 is located on one side of the frame 48. A guide shaft 59 is fixedly installed inside the movable groove 55, and the guide shaft 59 passes through the sliding block 58. The operation of the control motor 56 drives the threaded screw 57 to rotate. The rotation of the threaded screw 57 adjusts the position of the sliding block 58. The guide shaft 59 guides the sliding block 58. When the sliding block 58 moves, the electromagnet 60 can drive the frame 48 to move, thus facilitating the removal of the frame 48 from or into the storage slot 47 for storage. When the control electromagnet 60 is turned off, it no longer generates magnetic force and no longer limits the frame 48. The closed door at the bottom of the storage slot 47 can be opened to disassemble the frame 48 and process the stored products.

[0054] Furthermore, a wind box 61 is fixedly installed on the side of the frame 17, a fan 62 is fixedly installed inside the wind box 61, a third impeller 63 is fixedly installed inside the fan 62, a fourth impeller 67 is fixedly installed on the drive shaft 21, and the fourth impeller 67 and the third impeller 63 are connected by belt drive. The output end of the fan 62 is connected to the end of the heat absorption pipe 40 through a pipe. When the drive shaft 21 rotates, the fan 62 can be driven to work and generate wind through the cooperation of the fourth rotating wheel 67 and the third rotating wheel 63. After the wind flows into the heat absorption pipe 40, it cools the interior of the cooling chamber 13. The wind after absorbing heat will flow into the nozzle 43 through the pipe.

[0055] A method for using a plasma-arc chemical vapor deposition (CVD) apparatus includes the following steps: S1. Plasma gas is introduced into the hollow graphite cathode 6, and an electric arc is generated between it and the anode graphite crucible 4 containing the anode metal 5. The evaporation chamber 7 is preheated to the specified temperature to melt the anode metal 5. At the same time, the slag discharge port of the slag discharge pipe 8 is opened to discharge the generated metal slag particles. S2. Turn on the CVD growth chamber 9 to heat it, and raise the temperature to the growth temperature through the electric heating coil 12. At this time, close the slag discharge outlet. S3. Start the feeding mechanism to send the catalyst and co-catalyst from the hollow graphite cathode 6 into the evaporation chamber 7 to generate a catalyst mixture, which quickly enters the CVD growth chamber 9 under the reflection of the V-shaped structure. S4. A mixture of carrier gas and carbon source is introduced through carbon source gas channel 10, and reacts with the catalyst mixture in CVD growth chamber 9. After cooling, the mixture is collected at the tail gas outlet to obtain the final product.

[0056] Working principle: First, plasma gas is introduced into the hollow graphite cathode 6, initiating an electric arc between it and the anode graphite crucible 4 containing the anode metal 5. The evaporation chamber 7 is preheated to a specified temperature, melting the anode metal 5. Simultaneously, the slag discharge port of the slag discharge pipe 8 is opened to discharge the generated metal slag particles. The CVD growth chamber 9 is then heated, and the temperature is raised to the growth temperature via the electric heating coil 12. At this point, the slag discharge port is closed, and the feeding mechanism is opened to feed the catalyst and co-catalyst through the hollow graphite cathode 6 into the evaporation chamber 7, generating a catalyst mixture. Under the reflection of the V-shaped structure, the mixture rapidly... Entering the CVD growth chamber 9, the mixture of carrier gas and carbon source gas is introduced through the carbon source gas channel 10, and reacts with the catalyst mixture in the CVD growth chamber 9. After cooling, it flows with the airflow. The exhaust gas and product flow into the ventilation channel 46 through the conical groove 44. There are three sets of frame bodies 48. The first one, closest to the conical groove 44, passes through the ventilation channel 46. After the frame body 48 enters the ventilation channel 46, it intercepts the transverse section of the ventilation channel 46, so that the exhaust gas carrying the product can only flow into the filter cartridge 49. 9 can screen and process products and exhaust gas. The products are stored inside the filter cartridge 49, while the exhaust gas flows to the outside through the other side of the filter 41. The other end of the filter 41 can be connected to equipment for treating exhaust gas. When the filter cartridge 49 contains too much product, one side of the frame 48 can be controlled to move upward, so that the frame 48 moves into the ventilation slot 46. Before the frame 48 fully enters the ventilation slot 46, the push rod 52 will first contact the top of the inner wall of the ventilation slot 46. The downward movement of the push rod 52 will push the baffle 51 downward. After the filter cylinder 49 is moved, one side is no longer blocked. At the same time, the frame 48 for screening products is controlled to move downward. When the frame 48 moves downward, the return spring 53 returns to its original position, which pushes the baffle 51 and push rod 52 to return to their original positions. The baffle 51 will block the end of the filter cylinder 49, which can effectively prevent the stored products from falling accidentally. The frame 48 can also be disassembled and replaced, which is convenient for storing the stored products. The above steps can be repeated to screen and store products without stopping the machine, ensuring work efficiency and avoiding production capacity loss caused by downtime.

[0057] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of the present invention is defined by the appended claims and their equivalents.

Claims

1. A plasma-arc chemical vapor deposition (CVD) apparatus, characterized in that: The system includes a base plate (1), a support (2) fixedly mounted on the top of the base plate (1), a reaction chamber (3) mounted on the support (2), an anode graphite crucible (4) fixedly mounted inside the reaction chamber (3), an anode metal (5) mounted inside the anode graphite crucible (4), an evaporation chamber (7) mounted inside the reaction chamber (3), a CVD growth chamber (9) mounted inside the reaction chamber (3), and the evaporation chamber (7) and the CVD growth chamber (9) are connected in a V-shape. A hollow graphite cathode is fixedly mounted inside the reaction chamber (3). 6), and the end of the hollow graphite cathode (6) is located above the anode graphite crucible (4). The reaction box (3) is provided with a carbon source gas channel (10), and the carbon source gas channel (10) is connected to the CVD growth chamber (9). The CVD growth chamber (9) is provided with an array of electric heating coils (12). The CVD growth chamber (9) is also connected with an exhaust pipe (11). The reaction box (3) is provided with a slag discharge pipe (8), and the slag discharge pipe (8) is connected to the evaporation chamber (7). The exhaust pipe (11) is provided with a cooling component. A feeding mechanism is provided on the base plate (1), and a filter (41) is fixedly provided on the reaction box (3). A connecting pipe (42) is connected to the bottom end of the filter (41), and the other end of the connecting pipe (42) is connected to the end of the exhaust pipe (11). A screening mechanism is provided inside the filter (41).

2. The plasma-arc chemical vapor deposition (CVD) apparatus according to claim 1, characterized in that: The cooling assembly includes a cooling chamber (13) and a heat absorption tube (40). The cooling chamber (13) is located inside the exhaust pipe (11), and the heat absorption tube (40) is arranged around the exhaust pipe (11). The side of the reaction chamber (3) is provided with an opening and closing door (14). The side of the hollow graphite cathode (6) is connected to a connector (65). A seamless gas cylinder (66) is fixedly installed on the base plate (1), and the output end of the seamless gas cylinder (66) is connected to the connector (65) through a pipe.

3. The plasma-arc chemical vapor deposition (CVD) apparatus according to claim 2, characterized in that: The feeding mechanism includes a static mixer (15) and a gas storage tank (16). The static mixer (15) is mounted on the base plate (1), and the output end of the static mixer (15) is connected to the carbon source gas channel (10) through a pipe. The array of gas storage tanks (16) for storing carbon source gas is mounted on the base plate (1), and the output end of the gas storage tank (16) is connected to the input end of the static mixer (15) through a pipe. The feeding mechanism also includes a rotating component, a support frame (23), a storage tank (24), a discharge pipe (25), and a mixing component. The rotating component is mounted on the base plate (1), the support frame (23) is mounted on the rotating component, the array of storage tanks (24) for storing catalysts and co-catalysts is mounted on the support frame (23), the discharge pipe (25) is mounted below the storage tanks (24), the mixing component is mounted below the storage tanks (24), and the mixing component is connected to the hollow graphite cathode (6).

4. The plasma-arc chemical vapor deposition (CVD) apparatus according to claim 3, characterized in that: The rotating assembly includes a frame (17), a load-bearing frame (18), a reducer (19), a servo motor (20), and a drive shaft (21). The frame (17) is fixed on the base plate (1), the load-bearing frame (18) is fixed on the top of the frame (17), the reducer (19) is fixed inside the frame (17), the servo motor (20) is fixed inside the frame (17), and the output end of the servo motor (20) is fixedly connected to the input end of the reducer (19). The drive shaft (21) is rotatably disposed inside the load-bearing frame (18), and one end of the drive shaft (21) is fixedly connected to the output end of the reducer (19), and the other end of the drive shaft (21) is fixedly connected to the center position of the support frame (23). A drive wheel (22) is fixedly disposed on the drive shaft (21), and a load-bearing plate (26) is fixedly disposed on the load-bearing frame (18). The mixing assembly includes a mixing tank (27), a rotating shaft (29), and stirring blades (30). The mixing tank (27) is fixed on a load-bearing plate (26). The rotating shaft (29) is rotatably disposed inside the mixing tank (27). The stirring blades (30) are arranged in an array on the mixing tank (27). A transmission groove (28) is fixedly disposed on the load-bearing plate (26), and one end of the transmission groove (28) extends into the mixing tank (27). One end of the rotating shaft (29) extends into the transmission groove (28). 29) A driven wheel (31) is fixedly installed at the top. A transmission rod (33) is installed inside the transmission groove (28). A first rotating wheel (32) is fixedly connected to the top of the transmission rod (33). The first rotating wheel (32) is connected to the driven wheel (31) by a belt drive. A second rotating wheel (34) is fixedly installed on the transmission rod (33). The load-bearing plate (26) is hollow. The second rotating wheel (34) is connected to the drive wheel (22) by a belt drive. A drive block (35) is fixedly installed on the second rotating wheel (34).

5. The plasma-arc chemical vapor deposition (CVD) apparatus according to claim 4, characterized in that: The load-bearing plate (26) is fixedly equipped with a vibration frame (36), the vibration frame (36) is equipped with a striking block (37), the vibration frame (36) is fixedly equipped with a first spring (39), and one end of the first spring (39) is fixedly connected to the striking block (37). The striking block (37) is fixedly connected with a pressure plate (38), and the pressure plate (38) is located on one side of the second rotating wheel (34).

6. The plasma-arc chemical vapor deposition (CVD) apparatus according to claim 2, characterized in that: The filter (41) is fixedly provided with a nozzle (43), and the nozzle (43) is connected to the end of the heat absorption pipe (40) through a pipe. The filter (41) is fixedly provided with a conical groove (44).

7. The plasma-arc chemical vapor deposition (CVD) apparatus according to claim 6, characterized in that: The screening mechanism includes a square frame (45), a ventilation slot (46), a storage slot (47), a frame body (48), and filter cartridges (49). The square frame (45) is fixed inside the filter (41) and is located on one side of the conical slot (44). The ventilation slot (46) is located on the top of the square frame (45) and is connected to one end of the conical slot (44). The storage slots (47) are arranged in an array inside the square frame (45). The frame body (48) is arranged inside the storage slots (47). The filter cartridges (49) are arranged in an array inside the frame body (48). The frame (48) is provided with a sliding groove (50), and a baffle (51) is provided inside the sliding groove (50). The baffle (51) is located on one side of the filter cartridge (49). A push rod (52) is fixedly provided on the top of the baffle (51). A reset spring (53) is fixedly provided inside the baffle (51). A limiting plate (54) is fixedly provided inside the sliding groove (50), and the limiting plate (54) passes through the baffle (51). One end of the reset spring (53) is fixedly connected to the limiting plate (54).

8. The plasma-arc chemical vapor deposition (CVD) apparatus according to claim 7, characterized in that: The storage slot (47) has a movable slot (55) on its side. A power motor (56) is fixedly installed inside the movable slot (55). A threaded screw (57) is fixedly connected to the output end of the power motor (56). The end of the threaded screw (57) is rotatably connected to the inside of the movable slot (55). A corrugated tube is sleeved on the threaded screw (57) to protect the surface of the threaded screw (57). A sliding block (58) is installed inside the movable slot (55). The threaded screw (57) is threadedly connected to the sliding block (58). An electromagnet (60) is fixedly installed on the side of the sliding block (58). The electromagnet (60) is located on one side of the frame (48). A guide shaft (59) is fixedly installed inside the movable slot (55). The guide shaft (59) passes through the sliding block (58).

9. The plasma-arc chemical vapor deposition (CVD) apparatus according to claim 4, characterized in that: A bellows (61) is fixedly installed on the side of the frame (17). A fan (62) is fixedly installed inside the bellows (61). A third impeller (63) is fixedly installed inside the fan (62). A fourth impeller (67) is fixedly installed on the drive shaft (21). The fourth impeller (67) and the third impeller (63) are connected by belt drive. The output end of the fan (62) is connected to the end of the heat absorption pipe (40) through a pipe.

10. A method for applying a plasma-arc chemical vapor deposition (CVD) apparatus applicable to the plasma-arc chemical vapor deposition (CVD) apparatus according to any one of claims 1-9, characterized in that, Includes the following steps: S1. Plasma gas is introduced into the hollow graphite cathode (6) and an electric arc is generated between it and the anode graphite crucible (4) containing the anode metal (5). The evaporation chamber (7) is preheated to the specified temperature to melt the anode metal (5). At the same time, the slag discharge port of the slag discharge pipe (8) is opened to discharge the generated metal slag particles. S2. Turn on the CVD growth chamber (9) to heat it, and raise the temperature to the growth temperature through the electric heating coil (12). At this time, close the slag discharge outlet. S3. Turn on the feeding mechanism to send the catalyst and co-catalyst from the hollow graphite cathode (6) into the evaporation chamber (7) to generate a catalyst mixture, which quickly enters the CVD growth chamber (9) under the reflection of the V-shaped structure. S4. A mixture of carrier gas and carbon source is introduced through the carbon source gas channel (10) and reacted together with the catalyst mixture in the CVD growth chamber (9). After cooling, the final product is collected at the tail gas outlet with the gas flow.

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