TWI343361B - Method for making carbon nanotubes - Google Patents

Description

1343361

IX. Description of the Invention: [Technical Field to Which the Invention Is Ascribed] The present invention relates to a method for producing a carbon nanotube. [Prior Art]

Since the Japanese researcher Mr. Iijima first discovered the nanocarbon officer in the arc discharge product in 1991, it has excellent performance in mechanical, electronic, physical, chemical, etc., such as unique metal or semiconductor conductivity, extremely high. The mechanical strength, high-capacity hydrogen storage capacity and adsorption capacity, field-induced electron emission performance, directional thermal conductivity and strong broadband electromagnetic wave absorption characteristics make the carbon nanotubes subject to physical 'chemistry and materials science and other fields and high-tech industries. The department attaches great importance to it and promotes the extensive research and practical application of nanocarbon officials. At present, carbon nanotubes can be used as reinforcing materials for composite materials, field electron emission materials, supercapacitor electrode materials, gas adsorbing materials, catalytic materials, heat conducting materials, and sensing materials. However, with the development of nanocarbon tube performance and application research, how to obtain the required carbon nanotubes becomes more and more important. Generally, there are three main methods for manufacturing relatively mature carbon nanotubes: arc discharge method, laser burnt method, and chemical vapor deposition method. Its towel and chemical vapor deposition method have been widely studied and applied because of its simple and simple technology, low cost, easy control of the size of the carbon nanotubes, large length, high yield and batch growth of materials. '

The chemical vapor deposition method mainly uses a nanometer-scale transition metal or its oxide as a catalyst, and catalyzes the carbon-discharging at a constant temperature to catalyze the cracking of the raw rice carbon tube. The prior art provides a method for preparing a carbon nanotube, which comprises the steps of: providing a substrate; forming a layer on the surface of the substrate; forming a transition metal catalyzed contact on the surface of the surface layer; A chemical reaction takes place under the action of the catalyst, so that the carbon nanotubes grow from the catalyst layer. However, in the process of growing the carbon nanotubes, the carbon nanotubes will immediately grow into the carbon source gas. The carbon decomposition of the carbon source gas will first diffuse into the interior of the metal catalyst particles, and the carbon in the homogeneous τ will be saturated. (4) When the degree is reached, it will precipitate, thereby growing the nanocarbon. It takes a certain time for β to pass through the private product, so the growth rate of the carbon nanotubes is limited. [It is necessary to provide a 1 nm carbon tube manufacturing method that can rapidly grow carbon nanotubes. Hereinafter, a method for producing a carbon nanotube will be described by way of examples. 6 1343361

In order to achieve the above, a carbon nanotube manufacturing method is provided, comprising the steps of: providing a substrate; forming a composite film layer on the surface of the substrate, the composite film layer comprising a plurality of catalyst metal ruthenium layers and a plurality of carbon film layers; The composite film layer is heat-treated to form a catalyst layer containing a metal carbide; and a chemical vapor deposition growth carbon nanotube is performed on the catalyst layer. Wherein the catalyst metal is selected from the group consisting of tungsten, iron, cobalt, nickel or alloys thereof. The catalyst layer comprises a metal carbide, preferably tungsten carbide.

The number of layers of the plurality of catalyst metal films and the number of layers of the plurality of carbon film layers are respectively 1 〇 to 3 〇 layers, and may be formed by an ion plating method such as RF magnetron sputtering, vacuum evaporation or chemical vapor deposition. . The plurality of catalyst metal film layers have a thickness ranging from 3 nm to 3 nm, preferably 1 N. The plurality of carbon film layers have a thickness ranging from 3 nm to 3 nm, preferably 1 N. - The reduction of the composite film layer comprises the step of: at 9 (8). The temperature τ is heat-treated in an inert gas or a mixed gas atmosphere for 30 minutes or more; then, the temperature is lowered to room temperature. Then: == heat treatment comprises the steps of: using a rapid temperature at a temperature; the substrate is made of a material such as a stone tablet, a quartz plate or a metal sheet.

The chemical IU mesh deposition of the nanocarbon f takes the following steps: heating the catalyst layer to 00.X 'providing a carbon source gas, contacting it with the catalyst to cause the carbon nanotube to be on the catalyst layer It is selected from the group consisting of E, A or A mixed gas of A and A. e technology, the carbon nanotube manufacturing method provided by the embodiment, the composite layer passes through a hot layer, the carbon diffusion between the metal catalyst particles has reached saturation, and the carbon nanotubes can be secreted due to supersaturation. The growth provides a carbon source to accelerate the growth of the nematic transfer tube. [Embodiment] The technical solution will be further described in detail below with reference to the accompanying drawings. Figure. The method of manufacturing the nano carbon tube for the method of the present invention includes the following steps: (4) providing a substrate; (6) 7 J343361 = the base wire is handsome-faced, the dough is The layer includes a plurality of catalytic age-different layers and a plurality of film layers' (C) heat-treating the composite film layer to form a complex-aged lining and a plurality of carbon film 曰, a metal carbide catalyst layer; ) chemical vapor deposition on the catalyst layer • growth of na (f) f. Detailed instructions for each step of the next step. Step a: Providing a substrate 10, which may be a time plate, a quartz plate or a metal. Step b. Forming a composite film layer 2 on the surface of the substrate, the composite film layer 2 includes a plurality of catalyst gold layers and a fine layer. The method of forming the layer can be carried out by the secret submarine method, the radio frequency magnetron control, the true 2 evaporation method, and the chemical vapor deposition method. In this embodiment, the radio frequency magnetic control is used to extinguish the key method, and the surface is superimposed on the surface of the base and the bottom surface. The composite catalyst metal layer and the plurality of carbon film layers form a composite film layer 20. For the structure of the composite film layer 20 after the formation of the mountain, please refer to the second layer, the plurality of catalyst metal film layers 21 and the plurality of film layers 22 are superposed on each other, and the layers of the two film layers are respectively 1 〇 3 〇 layer, preferably. 2 layers. Wherein the metal material of the catalyst metal film layer 21 is preferably secret, iron, beginning, recorded or alloy thereof, and other metals such as rare earth metals and tungsten, iron, recorded alloys or soils and cranes, iron, cobalt, For the alloy of nickel, tungsten is used in this embodiment; the thickness of each layer of the catalyst metal film layer 21 is 3 3 Å, preferably 10 nm; the thickness of each layer of the carbon film layer 22 is 3 to 30 nm, preferably It is 10 nanometers. In addition, the plurality of catalyst metal film layers 21 and the plurality of carbon film layers 22 are alternately superimposed on the preferred embodiment of the present invention, but are not limited to the superposition sequence, and other random superposition methods or regular superposition methods are also formed in the composite film layer 20. Step c: The composite film layer 20 is heat treated to form a metal carbide-containing catalyst layer 30. The heat treatment can be carried out in two ways: (1) heat treatment at an inert gas (gas or argon, etc.) or a mixed gas atmosphere for 30 minutes or more, and then lowering the temperature to room temperature; or (2) at 900 ° A rapid thermal annealing treatment is applied at C temperature, and then the temperature is lowered to room temperature. When the composite film layer 20 is subjected to the above heat treatment, the super-saturated melt in which the catalyst metal film layer and the carbon film layer are first melted to generate carbon is melted in the catalyst metal to form a solid solution (s〇lids〇luti〇n), that is, The catalyst layer 30 containing the catalyst metallization, for example, the carbonized crane catalyst layer 3 of the present embodiment: wherein the catalyst particles in the catalyst layer 30 are nano-sized particles, and the particle diameter is preferably 2 to 2 nanometers a 8 8 1343361

Step d: chemical vapor deposition of the carbon nanotubes on the catalyst layer 30. When the upper treatment is cooled to room temperature, the 'super-saturated carbon will be precipitated from the metal matrix, heated to catalyze 500~900 °C' and then passed through a carbon source gas, such as methyl acetonide, acetylene or a mixture of methane and acetylene. The carbon produced by the cracking on the catalyst layer will grow on the carbon layer which is previously precipitated from the metal matrix = long, that is, the carbon nanotubes 4 are grown on the catalyst layer 30, preferably, the passable, '褒 is the carrier gas' In order to facilitate the regulation of the growth of carbon nanotubes. The method of manufacturing the carbon nanotubes of the Namimi, because the anti-expansion between the metal catalyst particles in the catalyst layer 3G has reached saturation 'field saturation, and the carbon precipitated can also be the source of the subsequent nano-carbon f' The linear speed of the carbon nanotubes can be used in the manufacture of semiconductor components and other precision manufacturing, such as in wafer fabrication and field emission display manufacturing. As stated on the silk, the invention meets the requirements of the invention, and the patent is filed by Sharp. However, the above mentioned only invented the reading of the good real customs, since Wei this _ the case of the cap. Anyone who is familiar with the skill of this case may be equivalent to (4) in the case of aiding the case, or change within the scope of the following patent application. ...匕3[Simple diagram description]

The first figure is a schematic diagram of a method for manufacturing a carbon nanotube according to an embodiment of the present technical solution. The second picture of the county's technology is relatively close to the nano-carbon method. Dan [Major component symbol description] Substrate Catalyst metal film catalyst layer 10 Composite film layer 21 Carbon film layer 30 Carbon nanotube layer 20 22 40

Claims (1)

1343361, the scope of patent application: 1. A method for manufacturing a nano-gorge tube, comprising the steps of: providing a substrate; forming a composite film layer on the surface of the base wire, the composite film layer comprising a plurality of catalyst metal film layers and a plurality of carbon films a layer; a heat treatment to form a catalyst layer containing a metal carbide; and chemical vapor deposition of the carbon nanotubes on the catalyst. The method for producing a carbon nanotube according to the above aspect, wherein the metal of the metal film layer is selected from the group consisting of tungsten or an alloy thereof with iron, cobalt and nickel. 3^ The method for manufacturing a carbon nanotube according to the scope of the patent application, including tungsten carbide. The method for producing a carbon nanotube according to the above aspect, wherein the number of the plurality of catalyst metal film layers and the number of layers of the plurality of carbon film layers is 1030 layers, respectively. The method for producing a carbon nanotube according to the above item 1, wherein the plurality of catalysts and the plurality of layers are formed by a film collection method, a radio frequency magnetron, a vacuum evaporation method or a chemical vapor deposition method. The method for producing a carbon nanotube according to any one of the items 1 to 5, wherein the plurality of catalyst metal film layers have a thickness ranging from 3 nm to 3 Torr. As for the side of the line, the weaving number reminds that the 丨8th tearing tube is made of silk, and the towel is the carbon nanotube manufacturing method according to one item, wherein the composite film layer atmosphere Medium heat two ship material. Just mixed gas η such as the sample to the room temperature to form a catalyst layer. The invention relates to a method for manufacturing a carbon nanotube according to the invention, wherein the ‘,, 、, includes the following steps: in the coffee. c Temperature _ fast enthalpy 8 10 U43361 degrees to temperature, forming a catalyst layer. 12_A material such as a nanodish heart, a stone tablet, a quartz plate or a metal piece as described in claim 1 of the patent application scope. The substrate is prepared by: using a carbon nanotube manufacturing method as described in the second aspect of the patent, μ ^ ', ', the catalyst layer is contacted to cause the carbon nanotube to grow on the catalyst layer. The method for producing a carbon nanotube according to claim 13, wherein the carbon source gas k is a mixed gas of acetylene, formazan and formazan.