CN102020262B - Method for growing single-walled carbon nanotubes in high efficiency without metal catalyst - Google Patents

Abstract

The invention relates to a preparation technology of single-wall nano-carbon tubes, in particular to a method for efficiently growing single-wall nano-carbon tubes without a metal catalyst, which is suitable for efficiently preparing high-quality single-wall nano-carbon tubes without metal impurities. In the method, silicon dioxide thin film prepared by ion sputtering method is used as a catalyst precursor, and single-wall carbon nanometer tubes are prepared by splitting carbon sources under the condition of 600-1100 DEG C. Among them, the carbon source is methane, ethane, ethylene, acetylene, benzene, toluene, cyclohexane and other hydrocarbons or ethanol, methanol, acetone, carbon monoxide, etc., and the carrier gas is hydrogen or hydrogen and argon, helium and other inert gases of the gas mixture. The present invention proposes to use the _SiO2 coated film obtained by the ion sputtering method as a catalyst precursor to efficiently grow high-quality single-walled carbon nanotubes without any metal impurities, which has the advantages of simple operation, low cost, and easy positioning and growth on silicon substrates. The characteristics of patterned growth of single-walled carbon nanotubes laid the foundation for the application of single-walled carbon nanotubes without metal impurities.

Description

A method for efficiently growing single-walled carbon nanotubes without metal catalysts

Technical field:

The invention relates to the preparation technology of single-walled carbon nanotubes, specifically a silicon dioxide (SiO ₂ ) film prepared by ion sputtering as a catalyst precursor without using any metal catalyst, on a silicon lining with a thermally oxidized layer A method for efficiently growing high-quality single-walled carbon nanotubes on the surface of high-temperature-resistant bulk materials of any shape (one-dimensional, two-dimensional, three-dimensional) such as the bottom, suitable for efficient preparation of high-quality single-walled carbon nanotubes that do not contain any metal impurities sample.

Background technique:

Single-walled carbon nanotubes are a typical representative of one-dimensional nanomaterials. Their excellent electrical, optical, thermal and mechanical properties make them widely used in nanoelectronic devices, optoelectronic devices, sensors, catalyst supports, composite materials, drug delivery and biomedicine. There are broad application prospects in other fields. Since the discovery of carbon nanotubes, their theoretical research and application exploration have always been frontier and hot topics in the fields of physical chemistry and materials science at home and abroad. Among them, the preparation of single-walled carbon nanotubes is the premise and basis for the research and application of single-walled carbon nanotubes.

After years of hard work by scientists from various countries, many achievements have been made in the preparation of single-wall carbon nanotubes. For example, by using transition metal catalysts such as iron, cobalt, and nickel, people have successfully realized single-wall, double-wall, and multi-wall nanotubes. The preparation of macroscopic bodies such as carbon tubes and their arrays, films, and oriented ropes, and the positioning, directional growth, and patterned growth of single-walled carbon nanotubes on the surface of silicon substrates have been basically realized. These achievements have greatly promoted the research progress of carbon nanotubes, but there are still many difficulties and challenges in the preparation of carbon nanotubes. For example, almost all current methods for preparing single-walled carbon nanotubes use metal catalysts, and the metal impurities remaining in single-walled carbon nanotubes will greatly affect the practical application of single-walled carbon nanotubes in many fields (such as nanoelectronics devices, optoelectronic devices, catalyst carriers, biological and medical fields, etc.). The purification methods that have been developed not only cannot completely remove the metal catalyst impurities in SWNTs, but also these post-treatment processes will inevitably damage the structure of SWNTs and reduce their quality. Therefore, the residual metal impurities in single-walled carbon nanotubes hinder people's research on their intrinsic structure and properties to a certain extent, and at the same time cause great obstacles to their practical applications in many fields. According to the growth process of carbon nanotubes, if no metal substance is used as a catalyst in the preparation process, then a sample of single-walled carbon nanotubes without any metal impurities will be obtained. This kind of single-walled carbon nanotubes without any metal impurities has great potential advantages and attractiveness for applications in the fields of single-walled carbon nanotubes-based nanoelectronic devices, optoelectronic devices, catalyst supports, biology and medicine.

Invention content:

The purpose of the present invention is to provide a high-quality, high-efficiency preparation method of single-wall carbon nanotubes without any metal impurities, which is a method for growing single-wall carbon nanotubes without metal catalysts. The method has the advantages of low cost, simple operation, good repeatability, positionable growth and patternable growth, etc.

Technical scheme of the present invention is:

A method for efficiently growing single-walled carbon nanotubes without a metal catalyst, the method uses silicon dioxide (SiO ₂ ) films prepared by ion sputtering as catalyst precursors, and silicon, silicon dioxide, silicon dioxide/silicon ( "Silicon dioxide/silicon" refers to a silicon substrate with a thermal oxidation layer of silicon dioxide on the surface), aluminum oxide, quartz, silicon carbide, etc., flat, spherical, or any shape (one-dimensional, two-dimensional, three-dimensional) high temperature resistant The bulk material is the substrate, and the single-walled carbon nanotubes are prepared by cracking the carbon source at high temperature. Specific steps are as follows:

First, SiO ₂ catalyst nanoparticles are formed on the surface of the substrate through reduction treatment; then, carbon source and carrier gas are passed through at high temperature, and the carbon active species released by the decomposition of carbon source is adsorbed on the surface of SiO ₂ catalyst nanoparticles, and is formed on the SiO ₂ Nucleation is assisted by catalyst nanoparticles, and finally forms single-walled carbon nanotubes.

In the present invention, the thickness of the SiO _catalyst film is 5-100nm, preferably in the range of 30-100nm;

In the present invention, the carbon source is one or more of hydrocarbons such as methane, ethane, ethylene, acetylene, benzene, toluene, and cyclohexane, and ethanol, methanol, acetone, or carbon monoxide, and the flow rate of the carbon source is 1～ 1000 ml/min, the preferred range is 5-500 ml/min.

In the present invention, the carrier gas is hydrogen; or, the carrier gas is a mixture of hydrogen and inert gases such as argon or helium (wherein the hydrogen volume ratio is ≥ 1/10), and the carrier gas flow rate is 1 to 2000 ml/min, preferably The range is 20-800 ml/min.

In the present invention, the reaction temperature is 600-1100°C, preferably in the range of 650-950°C.

The diameter of the single-wall carbon nanometer tube obtained by the invention is 0.8-2nm.

The beneficial effects of the present invention are:

1. The present invention proposes to use silicon dioxide (SiO ₂ ) film as the catalyst precursor, without using any metal catalyst to prepare high-quality single-walled carbon nanotubes, and there is no metal impurity in the product.

2. The silicon dioxide (SiO ₂ ) catalyst used in the present invention does not have the ability to catalyze the cracking of carbon sources, so the growth rate of single-walled carbon nanotubes can be greatly slowed down, and then the growth rate of single-walled carbon nanotubes can be realized by precisely controlling the reaction time. The control of the length of carbon nanotubes and the preparation of short single-wall carbon nanotubes are suitable for the controllable preparation of single-wall carbon nanotubes with different lengths, the shortest of which can reach ~20nm.

3. The method of the present invention is simple, efficient, good in repeatability and low in cost.

4. The present invention can realize the positional growth, patterned growth and integration of single-wall carbon nanotubes on the surface of silicon substrates, laying a foundation for their application in the field of nanoelectronic devices.

Description of drawings:

Fig. 1 is a schematic diagram of a reaction device for preparing single-walled carbon nanotubes without a metal catalyst. In the figure, 1 gas inlet; 2 high temperature resistant bulk material with silicon dioxide (SiO ₂ ) film sputtered on the surface; 3 thermocouple; 4 gas outlet.

Figure 2 is the characterization of the product single-walled carbon nanotubes. Among them, (a) is a scanning electron microscope picture; (b) is an atomic force microscope picture; (c) is a resonance laser Raman spectrum; (d) is a high-resolution transmission electron microscope picture.

Figure 3 is the X-ray photoelectron spectroscopy characterization of the product surface. Among them, (a) is the full spectrum; (b) is the high-resolution X-ray photoelectron spectroscopy of Fe element; (c) is the high-resolution X-ray photoelectron spectroscopy of Co element; (d) is the high-resolution X-ray photoelectron spectroscopy of Ni element X-ray photoelectron spectroscopy. The deep chromatographic line comes from the surface of the sample, and the shallow chromatographic line is the spectrum collected after the sample has undergone ion sputtering.

Fig. 4 is a growth rate curve of single-walled carbon nanotubes using silicon dioxide (SiO ₂ ) as a catalyst.

Fig. 5 is an atomic force microscope photo of short single-walled carbon nanotubes prepared with silicon dioxide (SiO ₂ ) as a catalyst. Wherein, (a) the growth time is 20 seconds, (b) the growth time is 40 seconds, and (c) the growth time is 60 seconds. (a), (b), and (c) the corresponding graphs on the right side are the statistical distribution graphs of the length of single-walled carbon nanotubes under the corresponding growth time.

Figure 6 shows the positional growth and patterned growth of single-walled carbon nanotubes (using a strip-shaped silicon wafer as a baffle when coating SiO ₂ films). Among them, (a) is a low-magnification scanning electron micrograph; (b) is a high-magnification scanning electron micrograph. In the figure, the bright area on the left is the area coated with SiO ₂ film, in which growing single-walled carbon nanotubes can be found; the dark area on the right is the area not coated with SiO ₂ film, in which no any single-walled carbon nanotubes.

Figure 7 shows the positional growth and patterned growth of single-walled carbon nanotubes (using a transmission electron microscope with a Cu microgrid as a baffle for SiO ₂ film plating). Among them, (a) is a low-magnification scanning electron micrograph; (b) is a high-magnification scanning electron micrograph. In the figure, each hollow of the micro-grid is an area coated with _SiO2 film, _and in this area, growth of single-walled carbon nanotubes (bright area) can be found; No single-walled carbon nanotubes were found (dark areas).

Figure 8 shows the patterned growth and positional growth of short single-walled carbon nanotubes using silicon dioxide (SiO ₂ ) as a catalyst. Among them, (a) is a schematic diagram of a tungsten (W) microgrid used when plating _SiO2 thin films, (b) is a scanning electron micrograph of short single-walled carbon nanotubes grown in a patterned and positioned manner, and (c) is The atomic force microscope photo of the solid-line rectangular area in b, and (d) is the atomic force micrograph of the dashed-line rectangular area in b.

Detailed ways:

The present invention is further described in detail below by way of examples and accompanying drawings.

Example 1

As shown in Figure 1, the device of the present invention adopts a horizontal reaction furnace, the two ends of the horizontal reaction furnace are respectively provided with a gas inlet 1 and a gas outlet 4, and the surface is sputtered with a silicon dioxide (SiO ₂ ) film of high temperature resistant block material 2 is placed in the high temperature zone of the horizontal reactor, and the thermocouple 3 is inserted into the high temperature zone of the horizontal reactor to monitor the reaction temperature in real time.

First, place the silicon substrate coated with _SiO2 thin film by ion sputtering method (the thickness of _SiO2 thin film is 30nm) in the central area of the horizontal reaction furnace (reaction area, there is a thermocouple at this position to monitor the furnace temperature in real time); Then, the _SiO2 film was heated to 900°C in a mixed gas atmosphere of hydrogen and argon (during the heating process, the flow rates of hydrogen and argon were 200 ml/min and 500 ml/min, respectively, and the heating rate of the reaction furnace was 40°C/min) After the furnace temperature rises to 900°C, feed the mixed gas of methane and hydrogen (the gas flow rate is respectively 500 ml/min of methane and 500 ml/min of hydrogen), and start to grow single-walled carbon nanotubes, and the growth time is 20 minutes. In this embodiment, the single-walled carbon nanotubes have a diameter of 0.8-2 nm and an average length of about 10 μm.

Scanning electron microscopy, atomic force microscopy, resonance laser Raman spectroscopy and high-resolution transmission electron microscopy observations show that the sample is a dense network of single-walled carbon nanotubes with a clean surface and high quality, and the density of single-walled carbon nanotubes is greater than 100 / μm ² .

Example 2

The device is shown in Figure 1.

First, the silicon substrate coated with _SiO2 film by ion sputtering method (the thickness of _SiO2 film is 100nm) is placed in the central area of the horizontal reaction furnace (reaction area, there is a thermocouple at this position to monitor the furnace temperature in real time); Then, the _SiO2 film was heated to 900°C in a mixed gas atmosphere of hydrogen and argon (during the heating process, the flow rates of hydrogen and argon were 200 ml/min and 500 ml/min, respectively, and the heating rate of the reaction furnace was 40°C/min) After the furnace temperature rises to 900°C, feed the mixed gas of methane and hydrogen (the gas flow rate is respectively 500 ml/min of methane and 500 ml/min of hydrogen), and start to grow single-walled carbon nanotubes, and the growth time is 20 minutes. In this embodiment, the single-walled carbon nanotubes have a diameter of 0.8-2 nm and an average length of about 10 μm.

Scanning electron microscopy, atomic force microscopy and resonance laser Raman spectroscopy observations show that the sample is a dense single-walled carbon nanotube network, and the density of single-walled carbon nanotubes is about 100/μm ² .

Example 3

The device is shown in Figure 1.

First, place the silicon substrate coated with _SiO2 thin film by ion sputtering method (the thickness of _SiO2 thin film is 30nm) in the central area of the horizontal reaction furnace (reaction area, there is a thermocouple at this position to monitor the furnace temperature in real time); Then, the _SiO2 film was heated to 650°C in a mixed gas atmosphere of hydrogen and argon (during the heating process, the flow rates of hydrogen and argon were 200 ml/min and 200 ml/min, respectively, and the heating rate of the reaction furnace was 30°C/min) ; After the furnace temperature rises to 650°C, ethanol is brought in by argon bubbling (wherein, the flow rate of argon is 50 ml/min, and the ethanol is placed in a Montessori washing bottle at 0°C), and hydrogen is introduced simultaneously (the gas flow rate is 500 ml/min), start to grow single-walled carbon nanotubes, and the growth time is 20 minutes. In this embodiment, the single-walled carbon nanotubes have a diameter of 0.8-2 nm and an average length of about 8 μm.

Scanning electron microscopy, atomic force microscopy, resonance laser Raman spectroscopy and high-resolution transmission electron microscopy observations show that the sample is a dense network of single-walled carbon nanotubes, the surface of the sample is very clean, and the quality is high. The density of single-walled carbon nanotubes is greater than 100 strands/μm ² .

Example 4

The device is shown in Figure 1.

First, place the silicon substrate coated with _SiO2 thin film by ion sputtering method (the thickness of _SiO2 thin film is 30nm) in the central area of the horizontal reaction furnace (reaction area, there is a thermocouple at this position to monitor the furnace temperature in real time); Then, the _SiO2 film was heated to 700°C in a mixed gas atmosphere of hydrogen and argon (during the heating process, the flow rates of hydrogen and argon were 200 ml/min and 200 ml/min, respectively, and the heating rate of the reaction furnace was 30°C/min) ; After the furnace temperature rises to 700°C, the mixed carbon source of ethanol and methanol is brought in by argon bubbling (wherein, the argon flow rate is 50 ml/min, and ethanol and methanol are placed in a Montessori washing bottle at 0°C , the volume ratio is 10:1), and at the same time, hydrogen gas (gas flow rate is 500 ml/min) is introduced to start growing single-walled carbon nanotubes, and the growth time is 20 minutes. In this embodiment, the single-walled carbon nanotubes have a diameter of 0.8-2 nm and an average length of about 9 μm.

Scanning electron microscopy, atomic force microscopy, resonance laser Raman spectroscopy and high-resolution transmission electron microscopy observations show that the sample is a dense network of single-walled carbon nanotubes, the surface of the sample is very clean, and the density of single-walled carbon nanotubes is about 80 / μm ² .

Example 5

The device is shown in Figure 1.

At first, adopt ion sputtering method to be coated with SiO ₂ The quartz ball of thin film (the thickness of SiO ₂ thin film is 30nm) is placed in the center area of horizontal reaction furnace (reaction area, there is thermocouple to monitor furnace temperature in real time at this position); Then , the _SiO2 film is heated to 900°C in a hydrogen and argon mixed gas atmosphere (the hydrogen and argon flow rates are respectively 200 ml/min and 500 ml/min during the heating process, and the heating rate of the reaction furnace is 40°C/min); After the furnace temperature rose to 900°C, a mixed gas of methane and hydrogen was introduced (the gas flow rates were respectively 500 ml/min of methane and 500 ml/min of hydrogen) to start growing single-walled carbon nanotubes for 20 minutes. In this embodiment, the single-walled carbon nanotubes have a diameter of 0.8-2 nm and an average length of about 10 μm.

Scanning electron microscopy, atomic force microscopy, resonance laser Raman spectroscopy and high-resolution transmission electron microscopy observations show that the sample is a dense network of single-walled carbon nanotubes with a clean surface and high quality, and the density of single-walled carbon nanotubes is greater than 100 / μm ² .

Example 6

The device is shown in Figure 1.

First, place the silicon substrate coated with _SiO2 thin film by ion sputtering method (the thickness of _SiO2 thin film is 30nm) in the central area of the horizontal reaction furnace (reaction area, there is a thermocouple at this position to monitor the furnace temperature in real time); Then, the _SiO2 film was heated to 900°C in a mixed gas atmosphere of hydrogen and argon (during the heating process, the flow rates of hydrogen and argon were 200 ml/min and 500 ml/min, respectively, and the heating rate of the reaction furnace was 40°C/min) After the furnace temperature rises to 900°C, feed the mixed gas of methane and hydrogen (the gas flow rate is respectively methane 500 ml/min and hydrogen 500 ml/min) to start growing single-walled carbon nanotubes, and the growth time is 20 seconds. In this embodiment, the single-walled carbon nanotubes have a diameter of 0.8-2 nm, an average length of about 149 nm, and a shortest length of ~20 nm.

Scanning electron microscope, atomic force microscope, resonance laser Raman spectrum and high-resolution transmission electron microscope observations show that the surface is clean and of high quality, and the density of single-walled carbon nanotubes is greater than 50/μm ² .

Example 7

The device is shown in Figure 1.

First, place the silicon substrate coated with _SiO2 thin film by ion sputtering method (the thickness of _SiO2 thin film is 30nm) in the central area of the horizontal reaction furnace (reaction area, there is a thermocouple at this position to monitor the furnace temperature in real time); Then, the _SiO2 film was heated to 900°C in a mixed gas atmosphere of hydrogen and argon (during the heating process, the flow rates of hydrogen and argon were 200 ml/min and 500 ml/min, respectively, and the heating rate of the reaction furnace was 40°C/min) After the furnace temperature rises to 900°C, feed the mixed gas of methane and hydrogen (the gas flow rate is respectively methane 500 ml/min and hydrogen 500 ml/min) to start growing single-walled carbon nanotubes, and the growth time is 40 seconds. In this embodiment, the single-walled carbon nanotubes have a diameter of 0.8-2 nm and an average length of about 342 nm.

Scanning electron microscope, atomic force microscope, resonance laser Raman spectrum and high-resolution transmission electron microscope observations show that the surface is clean and of high quality, and the density of single-walled carbon nanotubes is greater than 60/μm ² .

Example 8

The device is shown in Figure 1.

Use the Cu microgrid as a template by transmission electron microscopy to selectively vapor-deposit _SiO2 thin films on a part _of the surface of the silicon substrate _; In the central area of the horizontal reaction furnace (reaction area, there is a thermocouple in this position to monitor the furnace temperature in real time); then, the _SiO2 film is heated to 900 ° C in a hydrogen and argon mixed gas atmosphere (the hydrogen and argon flow during the heating process The speed is respectively 200 ml/min and 500 ml/min, and the heating rate of the reaction furnace is 40° C./min); minutes and hydrogen 500 ml/min), start to grow single-walled carbon nanotubes, and the growth time is 2 minutes. In this embodiment, the single-walled carbon nanotubes have a diameter of 0.8-2 nm and an average length of about 1 μm.

Scanning electron microscopy, atomic force microscopy, and resonant laser Raman spectroscopy observations revealed that a network of single-walled carbon nanotubes grew only in the regions patterned with _SiO2 films.

As shown in Figure 1, there are four mass flow meters at one end of the air inlet in the figure, which can selectively control the introduction of argon, helium, hydrogen, methane, ethane, carbon monoxide and other gases. Liquid carbon sources (such as ethanol, methanol, benzene, toluene, cyclohexane, etc.) are placed in a Montessori bottle at 0°C and brought in by bubbling argon or a mixture of argon and helium.

As shown in Figure 2, it can be seen from (a) scanning electron microscope and (b) atomic force microscope photos that the samples grown using SiO ₂ as a catalyst are dense films with a clean surface; from (c) resonance laser Raman It can be seen from the spectrum that the intensity ratio of the D mode to the G mode is about 0.04, indicating that the product single-walled carbon nanotubes are of high quality; from the (d) high-resolution transmission electron microscope photos, the product is a single-walled nanotube with a perfect structure. Carbon tubes, and most of them exist in the form of single or small tube bundles.

As shown in Figure 3, it can be seen from the X-ray photoelectron spectroscopy on the surface of the product that the sample only contains Si, O and C elements, and does not contain any other metal impurities, of which Si and O come from SiO ₂ coating.

As shown in Figure 4, the growth rate of single-walled carbon nanotubes with _SiO2 as the catalyst is only 8.3nm/s when the length of the single-walled carbon nanotubes grown in 20 seconds, 40 seconds and 60 seconds is calculated. The growth rate of single-wall carbon nanotubes is lower than that of ordinary metal catalysts (for example, under the same conditions, the growth rate of metal Co catalysts is 2.5 μm/s). It shows that when SiO ₂ is used as a catalyst, the growth rate of single-walled carbon nanotubes can be significantly slowed down, and then the purpose of precisely controlling its length and selectively growing short single-walled carbon nanotubes can be achieved.

As shown in Figure 5, it can be seen from the atomic force photos and length statistics of single-walled carbon nanotubes obtained at different reaction times that a series of short single-walled carbon nanotubes with adjustable length can be selectively obtained by simply controlling experimental parameters such as growth time. Walled carbon nanotube samples. For example, the average length of samples with a growth time of 20 seconds is only 149 nm, and the shortest length is only ~20 nm.

As shown in Figure 6, it can be seen from the positional growth and patterned growth of single-walled carbon nanotubes (using a strip-shaped silicon wafer as a baffle when coating SiO ₂ films), that only in the area coated with SiO ₂ films There are single-walled carbon nanotubes, indicating that the positioning growth of single-walled carbon nanotubes can be achieved by using a specific template, which lays the foundation for its application in the field of nanoelectronic devices.

As shown in Figure 7, it can be seen from the positional growth and patterned growth of single-walled carbon nanotubes (using a Cu microgrid as a baffle when coating SiO ₂ films by transmission electron microscopy) that only in the area coated with SiO ₂ films There are single-walled carbon nanotubes, indicating that the positioning growth of single-walled carbon nanotubes can be achieved by using a specific template.

As shown in Figure 8, it can be seen from the positional growth and patterned growth of single-walled carbon nanotubes (using a transmission electron microscope with a W microgrid as a baffle when coating _SiO2 films), only in the area coated with _SiO2 films There are single-walled carbon nanotubes, indicating that the positioning growth of single-walled carbon nanotubes can be achieved by using a specific template. In addition, SWNTs can be localized and grown on catalyst strips with a width of only ~5 μm without obvious interpenetration, showing the precision of localized growth and patterned growth of SWNTs when _SiO2 is used as the catalyst. Much higher than ordinary metal catalysts, which laid the foundation for its application in the field of nanoelectronic devices.

The above results show that the present invention proposes to use the _SiO obtained by the ion sputtering method as a catalyst precursor to efficiently grow high-quality single-walled carbon nanotubes that do not contain any metal impurities. The characteristics of positional growth and patterned growth of single-walled carbon nanotubes have laid a foundation for the application of single-walled carbon nanotubes without metal impurities. In addition, the growth rate of single-walled carbon nanotubes using _SiO2 as a catalyst is significantly lower than that of metal catalysts, so their length can be precisely controlled by controlling the reaction time. Physical properties and applications provide the premise.

Claims (2)

1. the method for the efficient growing single-wall CNT of non-metal catalyst; It is characterized in that: this method is a catalyst precursor with the silica membrane of ion sputtering method preparation; High temperature resistant block materials with the random shape of silicon, silicon oxide, silicon oxide/silicon, aluminum oxide, quartz or silit is a substrate, and the cracking through carbon source under 600～1100 ℃ prepares SWNT;

At first, handle at substrate surface formation SiO through reduction ₂The catalyst nano particle; Then, at high temperature feed carbon source and carrier gas, carbon source is decomposed the carbon active specy that discharges and is adsorbed on SiO ₂The catalyst nano particle surface, and at SiO ₂The auxiliary nucleation down of catalyst nano particulate finally forms SWNT;

In the reaction process, carrier gas is a hydrogen; Perhaps, carrier gas is the gas mixture of hydrogen and rare gas element, and wherein hydrogen volume is than >=1/10, and the carrier gas overall flow rate is 1～2000 ml/min;

Silicon oxide/silicon is meant that there is the silicon base of silicon-dioxide thermal oxide layer on the surface;

The carbon source flow velocity is 1～1000 ml/min;

SiO ₂Catalyst film thickness is 5～100nm;

In the reaction process, carbon source is one or more of methane, ethane, ethene, acetylene, benzene, toluene, hexanaphthene, ethanol, methyl alcohol, acetone, carbon monoxide.

2. according to the method for the efficient growing single-wall CNT of the described non-metal catalyst of claim 1, it is characterized in that: temperature of reaction is 650～950 ℃.

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