TWI481554B - Method for making nanowire structure - Google Patents

Description

Preparation method of nano structure

The invention relates to a preparation method of a nano structure, in particular to a preparation method of a nano structure using a carbon nanotube structure as a template.

Nanomaterials have great value in basic research and practical applications such as catalysis and sensing. Therefore, the preparation method of nanomaterials has become a research hotspot. At present, the preparation method of the nano material can be classified into a Spontaneous Growth method, a Template-Based Synthesis method, an Electrospinning method, a Lithography method, and the like.

The prior art provides a method for preparing titanium dioxide nanowires by electrospinning, see "Fabrication of Titania Nanofibers by Electrospinning" (Dan Li et al, Nano Letters, vol. 3, No. 4, p555-560 (2003)). . The method comprises mixing a mineral oil with an ethanol solution of polyvinylpyrrolidone (PVP) and a titanium dioxide precursor to prepare a slurry, and then preparing a titanium dioxide nanostructure by electrospinning. Further, the mineral oil and polyvinylpyrrolidone are evaporated by heating to obtain a pure titanium oxide nanostructure. The titanium dioxide nanostructure comprises a plurality of titanium dioxide nanowires and forms a self-supporting structure. Although the electrospinning method can prepare a nanowire having a large length and can be prepared into a nanostructure having a self-supporting structure, the electrospinning method usually requires a special electrospinning device and requires a high voltage, and The spinning material needs to be first formulated into a slurry. Therefore, the process of preparing the nano material by the electrospinning method is complicated and the cost is high.

Carbon Nanotube (CNT) is a new type of nanostructure obtained by Japanese researcher Iijima in laboratory for the first time in 1991. Please refer to “Helical Microtubules of Graphitic Carbon” (S.Iijima, Nature, vol. 354, p56 (1991)). Because the carbon nanotubes have one-dimensional morphology and chemical and thermal stability, they are ideal templates for template synthesis of nanomaterials.

The prior art provides a method for growing a tantalum nitride nanowire using a carbon nanotube as a template. Please refer to the application for publication of the Chinese mainland on December 19, 2005, and He Yanyang, which was published on July 19, 2006. CN1803586A. The method comprises the steps of: mixing the tantalum powder with the nanometer cerium oxide powder in a certain weight ratio; providing a double-layer corundum boat, and placing the mixture of the tantalum powder and the nanometer cerium oxide powder on the double-layer corundum The lower layer of the boat; a certain amount of carbon nanotube powder is placed on the upper layer of the double-layer corundum boat; the double-layer corundum boat is placed in a high-temperature furnace containing nitrogen for reduction and nitridation on the surface of the carbon nanotube Growing the tantalum nitride nanowire. In the reaction process, first, solid Si and SiO ₂ react to form SiO gas, and then the generated SiO gas reacts with nitrogen gas to form a tantalum nitride nanowire on the surface of the carbon nanotube. Compared with the preparation of nano materials by electrospinning, the stencil method is simple, easy to operate and low in cost.

However, the above method of growing a nanomaterial using a carbon nanotube as a template has the following disadvantages. First, the carbon nanotube as a template is a powder material having a limited length, so that the prepared tantalum nitride nanowire has a small length. Second, it is difficult to control the morphology of the product by using the carbon nanotube powder as a template. Third, the carbon nanotube powder is unevenly distributed and easily agglomerated, affecting the product. Size and uniformity. Fourth, the tantalum nitride nanowire prepared by the method cannot form a self-supporting structure (the so-called self-supporting structure means that the structure can maintain a specific shape such as a line or a film without a substrate), and its use is restricted.

Fan Shoushan et al. proposed a method for preparing nanocarbon tube ropes in 2002. Please refer to the mainland announcement patent CN100411979C on August 20, 2008. In 2007, a method for preparing nanocarbon tube film structure was proposed. Please refer to the publication No. CN101239712A of the mainland publication patent dated August 13, 2008. This patent/patent application provides a method of preparing a microscopic carbon nanotube into a macroscopic carbon nanotube structure. The carbon nanotube rope or the carbon nanotube membrane are both macroscopic carbon nanotube structures having a self-supporting property. However, the prior art does not disclose a method for preparing a nanostructure using a carbon nanotube structure having self-supporting properties as a template.

In view of the above, it is necessary to provide a method for preparing a nanostructure using a carbon nanotube structure having self-supporting properties as a template.

A method for preparing a nanostructure, comprising the steps of: providing a self-supporting carbon nanotube structure formed by a plurality of carbon nanotubes connected end to end as a template; introducing a reaction raw material to the carbon nanotube structure; The reaction raw material is initiated, and the reaction raw material is reacted to grow along the surface of the carbon nanotube structure to form a self-supporting nanostructure.

Compared with the prior art, since the carbon nanotube structure has self-supporting characteristics, the nano carbon tube structure can be used as a template to directly prepare a nano structure having self-supporting characteristics, and the process is simple and the cost is low.

The invention will be further described in detail below with reference to the accompanying drawings.

Referring to FIG. 1, the present invention provides a method for preparing a nanostructure, which comprises the following steps:

In step one, a carbon nanotube structure is provided.

The carbon nanotube structure comprises at least one carbon nanotube membrane, at least one nanocarbon pipeline or a combination thereof. When the carbon nanotube structure comprises a plurality of carbon nanotube membranes, the carbon nanotube membranes may be arranged in parallel without gaps or in parallel and overlapping. When the carbon nanotube structure includes only one nanocarbon line, the nanocarbon line can be folded or wound into a layered carbon nanotube structure. When the carbon nanotube structure comprises a plurality of nano carbon pipelines, the plurality of nanocarbon pipelines may be arranged in parallel, crosswise or woven into a layered carbon nanotube structure. When the carbon nanotube structure includes a carbon nanotube film and a nano carbon line, the nano carbon line may be disposed on at least one surface of the carbon nanotube film.

The carbon nanotube membrane comprises a plurality of uniformly distributed carbon nanotubes. The carbon nanotubes are ordered or disorderly distributed and tightly bound by van der Waals forces. The disordered arrangement of the carbon nanotubes is irregular, and the ordering means that at least a majority of the carbon nanotubes have a certain regular arrangement direction. When the carbon nanotube membrane comprises a disordered arrangement of carbon nanotubes, the carbon nanotubes are intertwined or isotropically arranged; when the carbon nanotube membrane comprises an ordered arrangement of carbon nanotubes, the carbon nanotubes Arrange in a preferred direction in one direction or in multiple directions. Specifically, the carbon nanotube film comprises a carbon nanotube film, a carbon nanotube film or a carbon nanotube film.

The carbon nanotubes in the carbon nanotube structure include one or more of a single-walled carbon nanotube, a double-walled carbon nanotube, and a multi-walled carbon nanotube. The single-walled carbon nanotube has a diameter of 0.5 nm to 50 nm, the double-walled carbon nanotube has a diameter of 1.0 nm to 50 nm, and the multi-walled carbon nanotube has a diameter of 1.5 nm to 50 nm. Nano. The carbon nanotubes have a length greater than 50 microns. Preferably, the length of the carbon nanotubes is preferably from 200 to 900 microns.

(1) The above preparation method of the carbon nanotube structure including the carbon nanotube film is specifically included in the following steps: First, an array of carbon nanotubes is provided.

In the present invention, the carbon nanotube array is a super-sequential carbon nanotube array. The carbon nanotube array provided by the present invention contains substantially no impurities such as amorphous carbon or residual catalyst metal particles. The carbon nanotubes in the array of carbon nanotubes are in close contact with each other to form an array by van der Waals force. The carbon nanotube array provided by the invention is one of a single-walled carbon nanotube array, a double-walled carbon nanotube array and a multi-walled carbon nanotube array.

Next, at least one carbon nanotube film is drawn from the carbon nanotube array.

The preparation of the carbon nanotube film comprises the following steps: selecting a plurality of carbon nanotube segments of a certain width from the carbon nanotube array, and the present invention preferably uses a tape having a certain width to contact the carbon nanotube array. Selecting at least one carbon nanotube segment of a certain width; stretching the plurality of carbon nanotube segments at a constant speed along a direction substantially perpendicular to the growth direction of the carbon nanotube array to form a continuous carbon nanotube film.

Referring to FIG. 2 and FIG. 3, the carbon nanotube film comprises a plurality of first and last phases. The carbon nanotube fragments 143 are evenly aligned. The length of the carbon nanotube segments 143 in the carbon nanotube film is substantially the same, and the carbon nanotube segment 143 includes a plurality of carbon nanotubes 145 having the same length and arranged in parallel with each other, and the carbon nanotubes 145 are They are closely connected by van der Waals. The carbon nanotubes 145 in the carbon nanotube film have the same alignment direction. Therefore, the carbon nanotube film comprises a plurality of carbon nanotubes 145 which are connected end to end and arranged in a preferred orientation.

Finally, a carbon nanotube structure was prepared by using the above carbon nanotube film.

The method for preparing the carbon nanotube structure specifically includes the following steps: providing a support body; laying at least one carbon nanotube film on the support body; removing excess nano carbon tube film from the support body to form a film Nano carbon tube structure. It can be understood that in the present invention, at least two carbon nanotube film can be overlapped and laid on the support to form a carbon nanotube structure. The carbon nanotube structure comprises a carbon nanotube film or at least two stacked carbon nanotube film, and the arrangement of the carbon nanotubes in the adjacent carbon nanotube film forms an angle. α, and 0°≦α≦90°.

The size of the support body can be determined according to actual needs, and can be a substrate or a frame. Since the carbon nanotube in the carbon nanotube array is very pure, and since the specific surface area of the carbon nanotube itself is very large, the carbon nanotube film itself has strong viscosity, and the carbon nanotube The film can be directly adhered to the support by its own viscosity. It can be understood that the present invention can also adhere the nano carbon tube film to the support by a bonding agent. The carbon nanotube film is adhered to the support body, and the excess carbon nanotube film portion outside the substrate or the frame can be scraped off with a small knife. It can be understood that when the carbon nanotube film is placed on a frame, the carbon nanotube film is suspended.

For the preparation method of the carbon nanotube film, please refer to the patent application of CN101239712A, published on August 13, 2008 by Fan Shoushan et al., "Nano Carbon Tube Film Structure and Preparation Method" (Applicant: Tsinghua University, Hongfujin Precision Industry (Shenzhen) Co., Ltd.).

Since the carbon nanotube structure has a certain self-supporting property, the carbon nanotube structure can be removed and used as a template to grow the nanostructure. In the present invention, for convenience of operation, the carbon nanotube structure provided on the substrate or the frame is directly used as a template growth nanostructure. It can be understood that the arrangement of the carbon nanotube structure on the substrate as a template growth nanostructure can control the speed of growing the nanostructure by selecting substrates of different thermal conductivity. The higher the thermal conductivity of the substrate, the faster the heat is conducted to the substrate, and the slower the conduction along the direction of the carbon nanotubes, so the slower the growth rate of the nanostructure. Otherwise, the faster the growth rate. Since the thermal conductivity of air is small, the nanostructure has the fastest growth rate when the carbon nanotube structure is suspended.

(2) A carbon nanotube structure using a nano carbon pipeline, the preparation method specifically comprising the following steps: First, preparing at least one nano carbon pipeline.

The nanocarbon pipeline includes a plurality of carbon nanotubes arranged in an axial/longitudinal direction along the nanocarbon pipeline. Specifically, the carbon nanotubes in the nanocarbon pipeline are arranged in an axially preferred orientation along the nanocarbon pipeline or axially helically arranged around the nanocarbon pipeline. The carbon nanotubes in the nanocarbon pipeline are tightly bonded by van der Waals force. Referring to FIG. 4, the carbon nanotubes in the nanocarbon pipeline are arranged in parallel along the axial/longitudinal direction of the nanocarbon pipeline. Referring to FIG. 5, the carbon nanotubes in the nano carbon pipeline are spiraled along the axial/longitudinal direction of the nanocarbon pipeline. arrangement.

The nano carbon pipeline shown in FIG. 4 is prepared by selecting a narrow carbon nanotube segment from the super-aligned carbon nanotube array and using a stretching tool directly from the carbon nanotube array. Pulling is obtained; or first pulling a carbon nanotube film from the above-mentioned super-aligned carbon nanotube array, and then obtaining the carbon nanotube film by organic solvent treatment. The organic solvent is a volatile organic solvent, and one or a mixture of one or more of ethanol, methanol, acetone, dichloroethane and chloroform may be used. The step of treating with an organic solvent may be performed by injecting an organic solvent into a surface of the carbon nanotube film by a test tube, or by immersing the formed carbon nanotube film in a container containing an organic solvent and then taking it out. . After the nano carbon tube film is infiltrated by an organic solvent, the nano carbon tube film is shrunk into a nano carbon line under the action of the surface tension of the volatile organic solvent. For the preparation method of the nano carbon pipeline, please refer to the patent application of CN 1982209A published by Fan Shoushan et al. on June 20, 2007, "Nano Carbon Tube and Its Manufacturing Method" (Applicant: Tsinghua University, Hongfujin Precision Industry (Shenzhen) Co., Ltd. and the announcement of China Mainland No. CN100411979C announced on August 20, 2008, “A Nano Carbon Pipe Rope and Its Manufacturing Method” (Applicant: Tsinghua University, Hong Fujin Precision Industry (Shenzhen) Co., Ltd.).

The nanocarbon line shown in FIG. 5 is prepared by twisting the nano carbon line shown in FIG. 4 or the above-mentioned carbon nanotube film by a mechanical external force.

Secondly, a carbon nanotube structure is prepared using the nano carbon line.

The method for preparing a carbon nanotube structure by using the nano carbon pipeline comprises: arranging a plurality of nano carbon pipelines in parallel, paralleling and cross-setting a plurality of nano carbon pipelines or weaving a plurality of nano carbon pipelines into one nanometer. Carbon tube structure.

(3) The method for preparing the carbon nanotube structure including the carbon nanotube rolled film specifically includes the following steps: First, providing a carbon nanotube array formed on a substrate, the array is an aligned carbon nanotube Array.

In the present invention, the carbon nanotube array is a super-sequential carbon nanotube array. The carbon nanotube array provided by the present invention contains substantially no impurities such as amorphous carbon or residual catalyst metal particles. The carbon nanotubes in the array of carbon nanotubes are in close contact with each other to form an array by van der Waals force. The carbon nanotube array provided by the invention is one of a single-walled carbon nanotube array, a double-walled carbon nanotube array and a multi-walled carbon nanotube array.

Secondly, a pressure device is used to extrude the carbon nanotube array to obtain a carbon nanotube rolled film. The specific process is as follows: in the present invention, an indenter can be used, the surface of the indenter is smooth, and the shape of the indenter is used. And the extrusion direction determines the arrangement of the carbon nanotubes in the prepared carbon nanotube rolled film. Specifically, when the planar indenter is pressed in a direction perpendicular to the substrate grown by the carbon nanotube array, the carbon nanotubes are obtained as isotropically arranged carbon nanotube rolled film; When the pressure head is rolled in a certain fixed direction, a carbon nanotube film which is aligned along the fixed direction of the carbon nanotubes can be obtained; when the roller-shaped indenter is rolled in different directions, the naphthalene can be obtained. Carbon nanotubes arranged in different directions Tube rolled film.

Depending on the way of rolling, the carbon nanotubes in the carbon nanotube rolled film can be arranged in a preferred orientation in a fixed direction, see Figure 6; or in a preferred orientation in different directions, see Figure 7. The plurality of carbon nanotubes form an angle α with the surface of the carbon nanotube rolled film, wherein α is greater than or equal to zero degrees and less than or equal to 15 degrees (0≦α≦15°). The carbon nanotube rolled film includes a plurality of carbon nanotubes arranged in a preferred orientation in the same direction or in different directions, and the carbon nanotubes are mutually attracted by van der Waals force, so the carbon nanotubes The laminated film has good toughness. In the carbon nanotube rolled film, the carbon nanotubes are evenly distributed and regularly arranged. The carbon nanotube rolled film has self-supporting properties and can be directly used as a carbon nanotube structure.

For the preparation method of the carbon nanotube rolled film, please refer to the patent application of the Chinese mainland No. 200710074027.5 on June 1, 2007, "Preparation method of the carbon nanotube film" (Applicant: Tsinghua University, Hong Fujin Precision Industry (Shenzhen) Co., Ltd.).

(4) The preparation method of the above carbon nanotube structure including the carbon nanotube flocculation membrane specifically comprises the following steps: First, a carbon nanotube raw material is provided.

The carbon nanotube raw material may be a carbon nanotube prepared by various methods such as chemical vapor deposition, graphite electrode constant current arc discharge deposition or laser evaporation deposition.

In the present invention, an array of aligned carbon nanotube arrays is scraped off the substrate using a blade or other tool to obtain a carbon nanotube material. Preferably, said In the carbon nanotube raw material, the length of the carbon nanotube is greater than 100 microns.

Next, the above carbon nanotube raw material is added to a solvent and subjected to flocculation treatment to obtain a nano carbon tube floc structure, and the above carbon nanotube floc structure is separated from the solvent, and the carbon nanotube is separated. The flocculated structure is shaped to obtain a carbon nanotube film.

The method for separating the carbon nanotube floc structure specifically comprises the steps of: pouring the solvent containing the carbon nanotube floc structure into a funnel with a filter paper; and drying for a period of time to obtain a separation. Nano carbon tube floc structure.

The shaping treatment process of the carbon nanotube floc structure specifically comprises the steps of: placing the above-mentioned carbon nanotube floc structure in a container; spreading the carbon nanotube floc structure according to a predetermined shape; applying A certain pressure is applied to the expanded carbon nanotube floc structure; and the residual solvent in the nano carbon tube floc structure is dried or the solvent is naturally volatilized to obtain a carbon nanotube flocculation film.

In addition, the step of separating and shaping the carbon nanotube floc structure can also be directly performed by suction filtration, and specifically includes the following steps: providing a microporous membrane and an extraction funnel; and the above-mentioned carbon nanotubes are included The solvent of the floc structure is poured into the suction funnel through the microporous membrane; after suction filtration and drying, a carbon nanotube flocculation membrane is obtained.

Referring to FIG. 8, the carbon nanotube film of the above-mentioned carbon nanotubes comprises intertwined carbon nanotubes, and the carbon nanotubes are mutually attracted and entangled by van der Waals to form a network structure, so the nanometer The carbon tube flocculation membrane has good toughness. In the carbon nanotube flocculation membrane, the carbon nanotubes are isotropic, both Evenly distributed, irregularly arranged. The carbon nanotube flocculation membrane has self-supporting properties and can be directly used as a carbon nanotube structure.

For the preparation method of the carbon nanotube flocculation membrane, please refer to the patent application of the Chinese mainland No. 200710074699.6 filed on April 13, 2007, "Preparation method of the carbon nanotube film" (Applicant: Tsinghua University, Hong Fujin Precision Industry (Shenzhen) Co., Ltd.).

Further, the present invention can also provide at least one nano carbon line on the surface of at least one carbon nanotube film to form a composite structure as a carbon nanotube structure.

In step two, a reaction raw material is introduced into the carbon nanotube structure.

The reaction starting material is not limited and is related to the nanostructure to be prepared. The reaction raw material may include one or more of a metal, a non-metal, and a semiconductor. For example, growing a metal oxide nanostructure, such as a nanowire of titanium oxide, aluminum oxide or nickel oxide, the reaction raw material may be a metal (such as titanium, aluminum or nickel) and an oxygen-containing gas; the growth metal telluride nanostructure For example, a nanowire of titanium telluride, iron telluride or nickel telluride, the reaction raw material may be a metal (such as titanium, iron or nickel) and a helium containing gas; a non-metallic nitride nanostructure, such as tantalum nitride, a reaction material It can be a source gas and a nitrogen gas; a non-metal carbide nanostructure, such as niobium carbide, the reaction raw material can be a source gas and a carbon source gas.

The method of introducing the reaction raw material into the carbon nanotube structure is not limited, and may include one or more of physical vapor deposition, chemical vapor deposition, dipping, spraying, and screen printing. It can be understood that different methods can be used to form a reaction raw material on the surface of the carbon nanotube in the carbon nanotube structure depending on the reaction raw materials. For example, by physical vapor deposition Metal or metal oxide is sputtered onto the surface of the carbon nanotube; non-metal nitride or carbide can be formed on the surface of the carbon nanotube by chemical vapor deposition; by dipping, spraying or screen printing The metal organic solution is formed on the surface of the carbon nanotube in the carbon nanotube structure. The reaction raw material may be partially or completely coated on the surface of the carbon nanotube or distributed in the form of a gas around the carbon nanotube. It can be understood that when the reaction raw material is deposited on the surface of the carbon nanotube structure, the thickness of the reaction raw material should be greater than 30 nm and less than or equal to 100 nm.

In the third step, the reaction raw material is initiated to react and grow the nanostructure.

The method of initiating the reaction raw material to carry out the reaction includes one or more of heating, laser irradiation, reactive sputtering, and the like. It can be understood that different methods can be selected to initiate the reaction of the reaction raw materials depending on the reaction conditions of the reaction raw materials. For example, by heating, the helium source gas and the carbon source gas can be reacted to prepare a niobium carbide nanostructure; by laser irradiation, the metal can react with oxygen to prepare a metal oxide nanostructure; by sputtering the metal particles in a vacuum, and simultaneously introducing The oxygen gas reaction can grow a metal oxide nanowire.

The reaction raw material is subjected to reaction growth of the nanowire under the reaction conditions. The nanowire grows along the length of the carbon nanotube in the carbon nanotube structure and coats the surface of the carbon nanotube. Since the carbon nanotubes in the carbon nanotube structure template used in the present invention are tightly combined by van der Waals force to form a carbon nanotube structure having self-supporting properties, the nanowires of the reaction growth are also formed. A nanostructure with self-supporting properties.

It can be understood that when a carbon nanotube film is used as a template, since the carbon nanotube film comprises a plurality of end-to-end and preferred orientations in the same direction The carbon nanotubes are arranged. Therefore, the prepared nanostructure includes a plurality of nanowires arranged in parallel along the carbon nanotubes, and the length of the nanowires is the same as the length of the carbon nanotube film. Since the length of the carbon nanotube film is not limited, it can reach several meters or more, so the length of the nanowire in the prepared nanostructure can reach several meters or more. By controlling the laying direction of the carbon nanotube film, it is also possible to control the arrangement direction of the nanowires in the nanostructure. When a carbon nanotube rolled film is used as a template, since the carbon nanotube rolled film includes a plurality of carbon nanotubes arranged in the same direction or in different directions, the prepared nanostructure includes a plurality of The nanowires are arranged in the same direction or in different directions. When a carbon nanotube flocculation membrane is used as a template, since the carbon nanotube flocculation membrane includes a plurality of intertwined carbon nanotubes, the prepared nanostructure includes a plurality of nanowires intertwined with each other.

Further, a step of separating the obtained nanostructure from the carbon nanotube structure to obtain a pure nanostructure may be included. The method of separation is related to the material of the obtained nanostructure. The present invention removes the carbon nanotube structure by a high temperature oxidation process. Specifically, the reaction product is placed in a high temperature furnace and maintained at 500 to 1000 ° C for 1 to 4 hours. It can be understood that the method for removing the carbon nanotube structure by high temperature oxidation is limited to preparing a high temperature resistant nanostructure such as a metal oxide, a non-metal nitride or the like.

The following is a specific embodiment of the invention for preparing a nanostructure using a carbon nanotube structure as a template:

Example 1

Referring to FIG. 9, a first embodiment of the present invention provides a method for preparing a nanostructure 104, which specifically includes the following steps:

In step one, a two-dimensional carbon nanotube structure 100 is prepared.

In this embodiment, two carbon nanotube films are stacked on a metal ring to obtain a carbon nanotube structure 100, and the carbon nanotubes in the two carbon nanotube films are arranged in the same direction.

In the second step, the reaction raw material 102 is introduced into the carbon nanotube structure 100.

In this embodiment, a layer of 100 nm thick titanium is deposited on the surface of the carbon nanotube structure 100 by magnetron sputtering. Referring to Figure 10, the titanium particles are evenly distributed on the surface of the carbon nanotubes in the carbon nanotube film.

In the third step, the reaction raw material 102 is initiated to react to grow the nanostructure 104.

In this embodiment, the carbon nanotube structure 100 deposited with the titanium layer is placed in an atmosphere such that the titanium particles on the surface of the carbon nanotube structure are in contact with oxygen in the atmosphere. Then, a self-diffusion reaction is initiated by laser scanning to obtain a two-dimensional titanium dioxide nanostructure 104. The nanostructure 104 includes a plurality of titanium dioxide nanowires arranged in parallel on the same plane. Among them, the speed of laser scanning is 10~200 cm/sec, and the power of laser scanning is 0.5~10 watts. The rate of the self-diffusion reaction is greater than 10 cm/sec.

The reaction starting material 102 is subjected to a reaction to grow the nanowire 106 under the reaction conditions. Since the carbon nanotube film is used as a template in the embodiment, the carbon nanotube film comprises a plurality of carbon nanotubes connected end to end and arranged in the same direction, and the nanowire 106 is stretched along the carbon nanotube. The first and last connected carbon nanotubes are grown and coated on the surface of the carbon nanotubes, so that a plurality of parallel aligned nanowires 106 are grown on the surface of the entire carbon nanotube structure 100. The length of the nanowire 106 is equal to the length of the carbon nanotube film. The plural The nanowires 106 arranged in parallel form a two-dimensional nanostructure 104.

In this embodiment, a plurality of titanium dioxide nanowires are prepared on the surface of the carbon nanotube film. Referring to FIG. 11, the titanium dioxide nanowires are grown along the carbon nanotubes connected end to end in the carbon nanotube structure to form a plurality of parallel titanium dioxide nanowires, and the titanium dioxide nanowires are coated on the nano carbon. Tube surface. Referring to FIG. 12, the microstructure of the titanium dioxide nanowire is a plurality of continuous small ellipsoid-like small particles uniformly dispersed or coated on the surface of the carbon nanotube.

Further, in the present embodiment, the titanium dioxide nanowire is heat-treated in an atmosphere to remove the carbon nanotube structure to obtain a pure titanium oxide nanostructure. The heat treatment temperature was 900 ° C, and the heat treatment rate of the heat treatment was 10 K / min. Referring to Figure 13, the pure titanium dioxide nanowires form a film having self-supporting properties. The thickness of the titanium dioxide film is less than 100 nm. The titanium dioxide nanowires in the titanium dioxide film have a length greater than 900 microns and a diameter less than 100 nanometers.

Since the present embodiment adopts a carbon nanotube film as a template to prepare a titanium dioxide nanowire, the carbon nanotube film comprises a plurality of carbon nanotubes connected end to end, and the carbon nanotubes connected end to end have a larger scale. (Up to several meters or more), the growth of the titanium dioxide nanowire can be controlled in a large range of several meters, and a two-dimensional nanostructure 104 composed of a relatively long titanium dioxide nanowire can be obtained. The larger length of the titanium dioxide nanowire is advantageous for its application in macroscopic devices.

Example 2

Referring to FIG. 14, a second embodiment of the present invention provides a nanostructure 204. Preparation. The preparation method of the nanostructure 204 is basically the same as the preparation method of the nanostructure in the first embodiment of the present invention, and the difference is that in the embodiment, two carbon nanotube films are overlapped and vertically cross-laid as a template growth. Nanostructure 204.

This embodiment specifically includes the following steps:

In the first step, a two-dimensional carbon nanotube structure 200 is prepared.

In this embodiment, two carbon nanotube films are overlapped and vertically laid on a metal ring to obtain a carbon nanotube structure 200. The carbon nanotubes in the two carbon nanotube films are arranged in a vertical direction.

In step two, the reaction raw material 202 is introduced into the two-dimensional carbon nanotube structure 200.

In the present embodiment, a layer of 100 nm of titanium is deposited as a reaction material 202 on both sides of the carbon nanotube structure 200 by magnetron sputtering.

In step three, the reaction starting material 202 is initiated to react to grow the nanostructure 204.

The reaction starting material 202 is subjected to a reaction to grow the nanowire 206 under the reaction conditions. Since the carbon nanotube film is used as a template in the embodiment, each of the carbon nanotube films comprises a plurality of carbon nanotubes connected end to end, and the arrangement direction of the carbon nanotubes in the two carbon nanotube films is arranged. Vertically, the nanowire 206 grows along the end-to-end carbon nanotubes in the carbon nanotube film and is coated on the surface of the carbon nanotube. Therefore, a plurality of nanowires 206 are formed on the surface of the carbon nanotube structure 200. The plurality of nanowires 206 form a two-dimensional nanostructure 204. The nanowire 206 portions of the two-dimensional nanostructure 204 are arranged in parallel along the first direction, and the portions are arranged in parallel along the second direction, and the first direction and the first The two directions are perpendicular to each other.

In this embodiment, two layers of titanium dioxide nanowires are provided on the surface of the carbon nanotube film. Referring to Figure 15, the titanium dioxide nanowire is coated on the surface of the carbon nanotube. Since the titanium dioxide nanowires are dispersed or coated on the surface of the carbon nanotubes, the macroscopic morphology of the titanium dioxide is consistent with the morphology of the carbon nanotube structure. Therefore, by controlling the laying angle of the carbon nanotube film, different angles of titanium dioxide nanowires can be prepared.

Example 3

Referring to FIG. 16, a third embodiment of the present invention provides a method for preparing a nanostructure 304. The preparation method of the nanostructure 304 is basically the same as the preparation method of the nanostructure in the first embodiment of the present invention, except that at least one nanocarbon pipeline is used as the template growth nanostructure 304 in the embodiment.

This embodiment specifically includes the following steps:

In step one, a one-dimensional carbon nanotube structure 300 is prepared.

The one-dimensional carbon nanotube structure 300 is a linear structure composed of a plurality of carbon nanotubes, and includes a single nano carbon line or a plurality of nano carbon lines arranged in parallel in a bundle. The nanocarbon line has a diameter of less than 100 nanometers. When the one-dimensional carbon nanotube structure 300 includes a plurality of nanocarbon lines arranged in parallel in a bundle, the spacing between the nanocarbon lines is greater than 5 nm to grow the nanowires. In this embodiment, the carbon nanotube structure 300 is a single carbon carbon pipeline. The nano carbon line has a diameter of 50 nm.

In step two, a reaction raw material 302 is introduced into the one-dimensional carbon nanotube structure 300.

In the present embodiment, a plurality of titanium particles are deposited as a reaction material 302 on the surface of the carbon nanotube structure 300 by magnetron sputtering. The titanium particles have a diameter of 10 to 50 nm.

In the third step, the reaction raw material 302 is initiated to react to grow the nanostructure 304.

The one-dimensional carbon nanotube structure 300 is a linear structure composed of a plurality of carbon nanotubes. The reaction starting material 302 is reacted under the reaction conditions and grown along the length of the one-dimensional carbon nanotube structure 300 to form a one-dimensional nanostructure 304. The nanostructure 304 consists of a single or a plurality of nanowires. When the one-dimensional nanostructure 304 is composed of a plurality of nanowires, a plurality of nanowires are arranged in a bundle.

Example 4

Referring to FIG. 17, a fourth embodiment of the present invention provides a method for preparing a nanostructure 404. The preparation method of the nano structure 404 is basically the same as the preparation method of the nano structure in the first embodiment of the present invention, and the difference is that the carbon nanotube film is prepared into a three-dimensional structure as a template growth nano structure 404 in this embodiment. .

This embodiment specifically includes the following steps:

In step one, a three-dimensional carbon nanotube structure 400 is prepared.

The three-dimensional carbon nanotube structure 400 can be obtained by folding or crimping the carbon nanotube film, the carbon nanotube film or the carbon nanotube film of the first embodiment. In this embodiment, the carbon nanotube film is placed on an aluminum frame 40, and the carbon nanotube film is rolled into a cylinder by the crimping frame 40. As a template.

In step two, a reaction material 402 is introduced into the three-dimensional carbon nanotube structure 400.

In this embodiment, a titanium layer is deposited as a reaction material 402 on the surface of the carbon nanotube structure 400 by magnetron sputtering. The titanium layer has a thickness of 50 nm.

In step three, the reaction starting material 402 is initiated to react to grow the nanostructure 404.

The reaction starting material 402 is subjected to a reaction-growth nanowire 406 under the reaction conditions. Since the three-dimensional carbon nanotube structure 400 includes a plurality of carbon nanotubes connected end to end, the nanowire 406 is grown along the end-to-end carbon nanotubes and is coated on the surface of the carbon nanotubes. The surface of the carbon nanotube structure 400 is grown to obtain a plurality of parallel aligned nanowires 406. The plurality of nanowires 406 are aligned parallel to the axis of the cylinder and form a three-dimensional nanostructure 404.

In summary, the present invention has indeed met the requirements of the invention patent, and has filed a patent application according to law. However, the above description is only a preferred embodiment of the present invention, and it is not possible to limit the scope of the patent application of the present invention. Equivalent modifications or variations made by persons skilled in the art in light of the spirit of the invention are intended to be included within the scope of the following claims.

100,200,300,400‧‧‧Nano carbon nanotube structure

102,202,302,402‧‧‧Reactive raw materials

104,204,304,404‧‧‧ nanostructure

106,206,406‧‧‧Nami line

143‧‧‧Nano carbon nanotube fragments

145‧‧・Nano carbon tube

1 is a flow chart of a method for preparing a nanostructure of the present invention.

2 is a scanning electron micrograph of a carbon nanotube film produced by the present invention.

3 is a schematic view showing the structure of a carbon nanotube segment in the carbon nanotube film of FIG. 2.

4 and 5 are scanning electron micrographs of a nanocarbon pipeline prepared by the present invention.

6 and 7 are scanning electron micrographs of a carbon nanotube rolled film prepared by the present invention.

Figure 8 is a scanning electron micrograph of a carbon nanotube film of the present invention.

Figure 9 is a flow chart showing the preparation process of the nanostructure according to the first embodiment of the present invention.

Figure 10 is a scanning electron micrograph of a structure of a carbon nanotube deposited with a titanium layer prepared in accordance with a first embodiment of the present invention.

Figure 11 is a scanning electron micrograph of oriented aligned titanium dioxide nanowires prepared in accordance with a first embodiment of the present invention.

Figure 12 is a transmission electron micrograph of oriented aligned titanium dioxide nanowires prepared in accordance with a first embodiment of the present invention.

Figure 13 is a scanning electron micrograph of a aligned titanium dioxide nanowire prepared by a first embodiment of the present invention after removal of a carbon nanotube template.

Figure 14 is a flow chart showing the preparation process of the nanostructure according to the second embodiment of the present invention.

Figure 15 is a scanning electron micrograph of a cross-mounted titanium dioxide nanowire prepared in accordance with a second embodiment of the present invention.

Figure 16 is a flow chart showing a process for preparing a nanostructure according to a third embodiment of the present invention.

Figure 17 is a flow chart showing a process for preparing a nanostructure according to a fourth embodiment of the present invention.

Claims (20)

A method for preparing a nanostructure, comprising the steps of: providing a self-supporting carbon nanotube structure formed by a plurality of carbon nanotubes connected end to end as a template; introducing a reaction raw material to the carbon nanotube structure; The reaction raw material is initiated, and the reaction raw material is reacted to grow along the surface of the carbon nanotube structure to form a self-supporting nanostructure. The method for preparing a nanostructure according to claim 1, wherein the carbon nanotube structure comprises at least one carbon nanotube film, at least one carbon nanotube rolled film, at least one nanometer. A carbon tube flocculation membrane, at least one nanocarbon line, or a combination thereof. The method for preparing a nanostructure according to claim 2, wherein the carbon nanotube film comprises a plurality of carbon nanotubes connected end to end and arranged in a preferred orientation in the same direction. The method for preparing a nanostructure according to claim 2, wherein a support is further provided, and at least one carbon nanotube film is disposed on the support. The method for preparing a nanostructure according to claim 4, wherein the support is a substrate or a frame. The method for preparing a nanostructure according to claim 2, wherein the carbon nanotube rolled film comprises a plurality of carbon nanotubes arranged in a preferred orientation in the same direction or in different directions. The method for preparing a nanostructure according to claim 2, wherein the carbon nanotube flocculation membrane comprises a plurality of intertwined carbon nanotubes. The method for preparing a nanostructure as described in claim 2, wherein The carbon nanotube structure includes a plurality of nano carbon pipelines arranged in parallel or in a cross arrangement. The method for preparing a nanostructure according to claim 2, wherein the nanocarbon pipeline comprises a plurality of carbon nanotubes arranged along an axially preferred orientation of the nanocarbon pipeline or around a carbon nanotube shaft. Arranged in a spiral. The method for preparing a nanostructure according to claim 2, wherein at least one nano carbon line is disposed on the carbon nanotube film, the carbon nanotube film or the carbon nanotube film At least one surface. The method for preparing a nanostructure according to claim 1, wherein the reaction raw material comprises one or more of a metal, a nonmetal, and a semiconductor. The method for preparing a nanostructure according to the first aspect of the invention, wherein the method for introducing a reaction raw material into a carbon nanotube structure comprises physical vapor deposition, chemical vapor deposition, dipping, and spraying. And one or more of the screen printing methods. The method for preparing a nanostructure according to claim 1, wherein the method of initiating the reaction raw material to perform the reaction includes one or more of heating, laser irradiation, and reactive sputtering. The method for preparing a nanostructure according to claim 1, wherein the step of initiating the reaction raw material to carry out the reaction to grow the nanostructure further comprises the step of removing the carbon nanotube structure by high temperature oxidation. The method for preparing a nanostructure according to claim 14, wherein the high temperature oxidation temperature is 500 to 1000 ° C, and the high temperature oxidation time is less than 4 hours. The method for preparing a nanostructure according to claim 1, wherein the nanostructure is identical to the morphology of the carbon nanotube structure. The method for preparing a nanostructure according to claim 1, wherein the carbon nanotube structure comprises a plurality of carbon nanotubes, and the nanostructure comprises a plurality of nanowires, the nanowire It grows along the length of the carbon nanotubes. A method for preparing a nanostructure, comprising the steps of: preparing a self-supporting carbon nanotube structure formed by connecting a plurality of carbon nanotubes end to end, the carbon nanotube structure being used as a template; Depositing a metal layer on the surface of the carbon tube structure; and oxidizing the metal layer to form a self-supporting metal oxide nanostructure along the surface of the nanostructure. The method for preparing a metal oxide nanostructure according to claim 18, wherein the metal layer has a thickness of more than 30 nm and less than or equal to 100 nm. The method for preparing a metal oxide nanostructure according to claim 18, wherein the method of oxidizing the metal layer comprises heating or laser irradiating the metal layer in an oxygen-containing environment.