CN101481788A - Preparation of single wall carbon nano-tube film - Google Patents
Preparation of single wall carbon nano-tube film Download PDFInfo
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- CN101481788A CN101481788A CNA2008100599332A CN200810059933A CN101481788A CN 101481788 A CN101481788 A CN 101481788A CN A2008100599332 A CNA2008100599332 A CN A2008100599332A CN 200810059933 A CN200810059933 A CN 200810059933A CN 101481788 A CN101481788 A CN 101481788A
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Abstract
The invention discloses a preparation method of single-walled carbon nanotube film. After a two-way or three-way catalyst which is prepared from metallic molybdenum powder, metallic ferrous powder, nickel powder, yttrium powder, cobalt powder, and the like in terms of certain proportion is filled in a graphite rod with a diameter (phi) of 6 x 50 mm so as to form a composite graphite anode that is installed inside an arc discharge device. The mol percentage of molybdenum powder is 0.1% to 2%, and the mol percentage of other metals is 0.5% to 5%. The mixed gas of hydrogen and argon is used according to the pressure ratio of 2: 3 and the total pressure of 150 to 250 Torr, or helium gas with the pressure of 150 to 250 Torr is used. The discharge current of the composite graphite anode is 50 to 100 A, and the arc discharge lasts 5 to 100 seconds. The single-walled carbon nanotube film can be obtained on the spherical crown shaped graphite cathode plate of the arc discharge device, and the rate of conversion is more than 90%. The area of the film prepared can be more than 100 to 230 cm2, and the thickness of the film is between microns and 1mm; and the film has certain directionality.
Description
Technical field
The present invention relates to a kind of preparation method of single-walled carbon nanotube film.
Background technology
Characteristics such as the Single Walled Carbon Nanotube (SWCNTs) of arc discharge method preparation has good crystallinity, and preparation time is short.But this method has also that productive rate is low, the deficiency of purity difference.Along with the continuous development of carbon nanotube research, the research of many application facet is starved of a large amount of highly purified Single Walled Carbon Nanotube.Utilizing arc discharge method to prepare on the more than ten years history of Single Walled Carbon Nanotube, there has been multiple metal catalyst to be used to prepare the preparation of Single Walled Carbon Nanotube.But these catalyst efficient are not very high, therefore, make arc discharge method be difficult to satisfy the needs of the high-quality Single Walled Carbon Nanotube of a large amount of preparations.
Available research achievements shows that Single Walled Carbon Nanotube has determined it can become a kind of type material with various performances such as good mechanics, electricity, and very wide application prospect is all arranged in a lot of fields because of himself having perfect structure.Single Walled Carbon Nanotube is made large area film have vital role for the performance of bringing into play its multiple excellence.Particularly all press for big area, high purity, high-quality single wall carbon nano-tube film, and have certain directivity at the aspects such as catalysis electrode film of matrix material, field emmision material, fuel cell.
Summary of the invention
The purpose of this invention is to provide a kind of preparation method of single-walled carbon nanotube film.
A kind of preparation method of single-walled carbon nanotube film is molybdenum powder and iron powder to be packed in the graphite rod of Φ 6 * 50mm form the composite graphite anode, and be installed in the arc discharge device, the molecular fraction of molybdenum powder is 0.1%～1%, the molecular fraction of iron powder is 0.2～1.6%, adopt the mixed gas of hydrogen and argon gas, hydrogen and argon pressure are than being 2:3, total pressure is under the condition of 150～250Torr, composite graphite anodic discharging current is 70～100A, arc-over 5～30 seconds is collected on the spherical negative electrode graphite pole plate negative electrode in arc discharge device and is obtained very thin single wall carbon nano-tube film.
Another kind of preparation method of single-walled carbon nanotube film is with molybdenum powder, nickel powder and yttrium powder are packed into the interior composite graphite anode that forms of graphite rod of Φ 6 * 50mm, and be installed in the arc discharge device, the molecular fraction of molybdenum powder is 0.1%～1%, the molecular fraction of nickel powder is 2%～5%, the molecular fraction of yttrium powder is 0.5%～1.3%, adopt helium, the pressure of helium is under the condition of 300～600Torr, composite graphite anode discharge electric current is 50～80A, arc-over 30～100 seconds is collected on the spherical negative electrode graphite pole plate negative electrode in arc discharge device and is obtained single wall carbon nano-tube film.
Another preparation method of single-walled carbon nanotube film is molybdenum powder and cobalt powder to be packed in the graphite rod of Φ 6 * 50mm form the composite graphite anode, and be installed in the arc discharge device, the molecular fraction of molybdenum powder is 0.1%～1.6%, the molecular fraction of cobalt powder is 0.3%～2%, adopt argon gas, the pressure of argon gas is under the condition of 150～300Torr, composite graphite anode discharge electric current is 50～80A, arc-over 30～100 seconds is collected on the spherical negative electrode graphite pole plate negative electrode in arc discharge device and is obtained single wall carbon nano-tube film.
It is the core component of catalyzer that the present invention utilizes with metal molybdenum (Mo), makes up by a certain percentage with other traditional metal catalyst, forms new catalyst new, that have efficient effect.These different metal catalysts are added in the Graphite Electrodes rod according to the fixed ratio, make catalyst composite electrode, be installed on the anode in the vacuum chamber of arc discharging device, vacuum chamber is under the atmosphere of inert gases of certain pressure, and the graphite rod that is installed on negative electrode in vacuum chamber carries out arc-over.On the negative electrode graphite pole plate in a kind of special device that spherical negative electrode graphite pole plate is formed by two pieces, can get single wall carbon nano-tube film.It is simple that the preparation method of this Single Walled Carbon Nanotube has technology, less investment, efficient height characteristics such as (its transformation efficiency have reached more than 90%).In addition, the Single Walled Carbon Nanotube quality better of preparing, the purity height, and also the thickness of single wall carbon nano-tube film can be controlled as required.Characteristic of the present invention is to prepare very thin single wall carbon nano-tube film, and thin can reach several microns, even thinner.And, the big (100～230cm of the area of the single wall carbon nano-tube film of preparing
2), the distribution of Single Walled Carbon Nanotube has certain directivity.
Description of drawings
Fig. 1 prepares the structural representation of single wall carbon nano-tube film device for arc discharge method;
Fig. 2 is that embodiment 1 uses molybdenum powder and iron powder binary catalyst, the Single Walled Carbon Nanotube electron scanning micrograph of preparation, and film surface has a large amount of carbon nanotube bundles, and has certain directivity, also has some granules of catalyst simultaneously;
Fig. 3 is the high power photo of the scanning electronic microscope of Fig. 2, and a large amount of carbon nanotube bundles is high-visible;
Fig. 4 is the Raman spectrogram of single wall carbon nano-tube film (at room temperature excitation wavelength is 514.5nm) for embodiment 1.By 1334cm
-1Decolorizing carbon peak and 1587cm
-1Single Walled Carbon Nanotube characteristic peaks intensity contrast nearby only contains the decolorizing carbon of trace, low frequency range 150～210cm as can be seen in the single wall carbon nano-tube film
-1The peak value of the breathing vibration film mean diameter that can obtain Single Walled Carbon Nanotube be 1.28nm;
Embodiment
As shown in Figure 1, the device that used arc discharge method prepares single wall carbon nano-tube film comprises arc-over vacuum chamber 3, the arc-over vacuum chamber is connected with vacuum pump 6, be provided with graphite cathode 5 and graphite anode 4 in the arc-over vacuum chamber, graphite cathode is connected with direct supply 7 with graphite anode, one of its feature is to install respectively spherical graphite cake 1 and following spherical graphite cake 2 on graphite cathode 5 and graphite anode 4, single wall carbon nano-tube film forms on last spherical graphite cake 1.
The present invention is by preparing the device of single wall carbon nano-tube film based on arc discharge method, install respectively on graphite cathode and the graphite anode a pair of spherical graphite cake and following spherical graphite cake, constitute the device of ball crown type electrical condenser (comprising the flat capacitor device), realize the target of preparation big area, high-quality single wall carbon nano-tube film.Feature of the present invention is that the arc-over of negative electrode graphite rod and the graphite anode rod that contains the high-level efficiency metal catalyst is carried out in the space that two pieces of ball crown type graphite pole plates form.In the discharge process,, therefore, be in the ball crown type graphite cathode plate of negative potential, have the character that attracts carbon ion owing to have electric field all the time between two pieces of ball crown type graphite pole plates.On the other hand, because the spaces that two pieces of ball crown type graphite pole plates form, change the diffusion form of carbon ion etc., increased the synthetic probability of Single Walled Carbon Nanotube.Simultaneously, charge under atmosphere of inert gases and the certain pressure at vacuum chamber, the high temperature evaporation that arc-over produces contain the graphite anode rod of metal catalyst, at this moment, carbon ion is because of effect of electric field and specific gaseous diffusion form, the synthetic Single Walled Carbon Nanotube is just with uniform form of film, almost all on the internal surface attached to last spherical graphite cathode plate.This single wall carbon nano-tube film has big area (100～200cm
2), highly purified characteristics, and the thickness of single wall carbon nano-tube film also can be controlled as required, thickness is between several microns to 1 millimeter magnitudes.Synthetic single wall carbon nano-tube film sample among the embodiment is studied and test shows through field emission scanning electron microscope (FSEM) and Raman (Raman) spectrographic, the transformation efficiency of the Single Walled Carbon Nanotube of preparing has reached more than 90%, mean diameter is 1.28nm, and length is the number micron dimension.Its electromicroscopic photograph and test curve are seen accompanying drawing 2～4.
The experiment condition of preparation single wall carbon nanocapsule thin film be with Mo and Fe, Co, Ni, Y, in one or more combination binary or three-way catalysts, it proportionally is mixed into uniform powder, mix with Graphite Powder 99 with certain proportion, be filled in the graphite rod that diameter is 6mm and be prepared into the composite graphite anode, negative electrode uses the graphite rod of diameter as 8mm, also can directly use circular arc graphite cake negative electrode.Atmosphere gas is high-purity He gas or hydrogen and argon gas mixed gas, pressure between 100～600Torr, by the anodic electric current between 50～100A.The graphite anodic-cathodic has formed single wall carbon nano-tube film implement arc-over in the space that spherical electrical condenser forms after on the internal surface of last spherical negative electrode graphite pole plate.
Embodiment 1:
Use molybdenum (Mo) powder and iron (Fe) powder binary catalyst, with the molybdenum of 0.2mol% and the iron of 1mol%, be packed in the graphite rod of Φ 6 * 50mm, with it is the composite graphite anode, and discharging current is 70A, uses the mixed gas of hydrogen and argon gas, its pressure ratio is 2:3, total pressure is under the condition of 250Torr, implements arc-over 45 seconds, and can collect quality on last spherical negative electrode graphite pole plate negative electrode is that 5.6mg, area reach 50cm
2Single wall carbon nano-tube film (thickness be hundreds of micron).
Embodiment 2:
Use molybdenum (Mo) powder and iron (Fe) powder binary catalyst, with the molybdenum of 0.2mol% and the iron of 1mol%, being packed in the graphite rod of Φ 6 * 50mm, is the composite graphite anode with it, and discharging current is 70A, use the mixed gas of hydrogen and argon gas, its pressure ratio is 2:3, and total pressure is under the condition of 200Torr, implements arc-over 30 seconds, collecting quality on circular arc graphite cake negative electrode is 5mg, and area reaches 40cm
2Single wall carbon nano-tube film (thickness hundreds of approximately micron).
Use molybdenum (Mo) powder and iron (Fe) powder binary catalyst, with the molybdenum of 0.2mol% and the iron of 1mol%, be packed in the graphite rod of Φ 6 * 50mm, with it is the composite graphite anode, discharging current is 70A, adopt the mixed gas of hydrogen and argon gas, hydrogen and argon pressure are than being 2:3, total pressure is under the condition of 150Torr, composite graphite anodic discharging current is 70A, arc-over 90 seconds is collected the area that obtains 9.8mg on the spherical negative electrode graphite pole plate negative electrode in arc discharge device and is reached 180cm
2Single wall carbon nano-tube film.
Embodiment 4
Use molybdenum (Mo) powder, nickel (Ni) powder and yttrium (Y) powder three-way catalyst, 0.2mol% molybdenum powder, 0.8mol% nickel powder and 0.2mol% yttrium powder are packed into the interior composite graphite anode that forms of graphite rod of Φ 6 * 50mm, and be installed in the arc discharge device, adopt helium, its pressure is under the condition of 300Torr, composite graphite anodic discharging current is 50A, and arc-over 100 seconds is collected the area that obtains 110mg on the spherical negative electrode graphite pole plate negative electrode in arc discharge device and reached 80cm
2Single wall carbon nano-tube film.
Use molybdenum (Mo) powder, nickel (Ni) powder and yttrium (Y) powder three-way catalyst, 0.2mol% molybdenum powder, 0.8mol% nickel powder and 0.2mol% yttrium powder are packed into the interior composite graphite anode that forms of graphite rod of Φ 6 * 50mm, and be installed in the arc discharge device, adopt helium, its pressure is under the condition of 300Torr, composite graphite anode discharge electric current is 70A, and arc-over 50 seconds is collected the area that obtains 68mg on the spherical negative electrode graphite pole plate negative electrode in arc discharge device and reached 100cm
2Single wall carbon nano-tube film.
Embodiment 6
Use molybdenum (Mo) powder, nickel (Ni) powder and yttrium (Y) powder three-way catalyst, 0.2mol% molybdenum powder, 0.8mol% nickel powder and 0.2mol% yttrium powder are packed into the interior composite graphite anode that forms of graphite rod of Φ 6 * 50mm, and be installed in the arc discharge device, adopt helium, its pressure is under the condition of 600Torr, composite graphite anode discharge electric current is 80A, and arc-over 30 seconds is collected the area that obtains 78mg on the spherical negative electrode graphite pole plate negative electrode in arc discharge device and reached 120cm
2Single wall carbon nano-tube film.
Use molybdenum (Mo) powder and cobalt (Co) powder binary catalyst, 0.2mol% molybdenum powder and 0.4mol% cobalt powder are packed in the graphite rod of Φ 6 * 50mm and form the composite graphite anode, and be installed in the arc discharge device, adopt argon gas, the pressure of argon gas is under the condition of 300Torr, and composite graphite anode discharge electric current is 60A, arc-over 30 seconds, collect on the spherical negative electrode graphite pole plate negative electrode in arc discharge device and obtain 5.5mg, area reaches 60cm
2Single wall carbon nano-tube film.
Embodiment 8
Use molybdenum (Mo) powder and cobalt (Co) powder binary catalyst, 0.2mol% molybdenum powder and 0.4mol% cobalt powder are packed in the graphite rod of Φ 6 * 50mm and form the composite graphite anode, and be installed in the arc discharge device, adopt argon gas, the pressure of argon gas is under the condition of 600Torr, and composite graphite anode discharge electric current is 80A, arc-over 100 seconds, collect on the spherical negative electrode graphite pole plate negative electrode in arc discharge device and obtain 11.3mg, area reaches 110cm
2More than, thickness is hundreds of microns single wall carbon nano-tube film.
Claims (3)
1. preparation method of single-walled carbon nanotube film, it is characterized in that, molybdenum powder and iron powder are packed in the graphite rod of Φ 6 * 50mm and form the composite graphite anode, and be installed in the arc discharge device, the molecular fraction of molybdenum powder is 0.1%～1%, the molecular fraction of iron powder is 0.2～1.6%, adopt the mixed gas of hydrogen and argon gas, hydrogen and argon pressure are than being 2:3, total pressure is under the condition of 150～250Torr, composite graphite anodic discharging current is 70～100A, and arc-over 5～30 seconds can obtain single wall carbon nano-tube film on the spherical graphite cathode in arc discharge device.
2. preparation method of single-walled carbon nanotube film, it is characterized in that, with molybdenum powder, nickel powder and yttrium powder are packed into the interior composite graphite anode that forms of graphite rod of Φ 6 * 50mm, and be installed in the arc discharge device, the molecular fraction of molybdenum powder is 0.1%～1%, the molecular fraction of nickel powder is 2%～5%, the molecular fraction of yttrium powder is 0.5%～1.3%, adopt helium, under the condition of the pressure 300～600Torr of helium, composite graphite anode discharge electric current is 50～80A, and arc-over 30～100 seconds is collected on the spherical negative electrode graphite pole plate negative electrode in arc discharge device and obtained single wall carbon nano-tube film.
3. preparation method of single-walled carbon nanotube film, it is characterized in that, molybdenum powder and cobalt powder are packed in the graphite rod of Φ 6 * 50mm and form the composite graphite anode, and be installed in the arc discharge device, the molecular fraction of molybdenum powder is 0.1%～1.6%, the molecular fraction of cobalt powder is 0.3%～2%, adopt argon gas, the pressure of argon gas is under the condition of 300～600Torr, composite graphite anode discharge electric current is 50～80A, arc-over 20～100 seconds is collected on the spherical negative electrode graphite pole plate negative electrode in arc discharge device and is obtained single wall carbon nano-tube film.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102179257A (en) * | 2011-04-15 | 2011-09-14 | 上海大学 | Preparation method of electro-catalyst of single-walled carbon nanotube loading platinum base for fuel cell |
Citations (5)
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| WO2000073205A1 (en) * | 1999-06-02 | 2000-12-07 | The Board Of Regents Of The University Of Oklahoma | Method of producing carbon nanotubes and catalysts therefor |
| CN1463918A (en) * | 2002-06-06 | 2003-12-31 | 中国科学院金属研究所 | Process for preparing single wall nano carbon tube |
| CN1712349A (en) * | 2004-06-15 | 2005-12-28 | 南开大学 | Arc synthesis of single-wall carbon nanometer tubes |
| CN1749156A (en) * | 2005-10-18 | 2006-03-22 | 南开大学 | Arc method for synthesizing controllable single wall carbon nano tube |
| CN1887701A (en) * | 2006-07-21 | 2007-01-03 | 太原理工大学 | Process of preparing single-wall carbon nanotube |
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- 2008-03-04 CN CNA2008100599332A patent/CN101481788A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2000073205A1 (en) * | 1999-06-02 | 2000-12-07 | The Board Of Regents Of The University Of Oklahoma | Method of producing carbon nanotubes and catalysts therefor |
| CN1463918A (en) * | 2002-06-06 | 2003-12-31 | 中国科学院金属研究所 | Process for preparing single wall nano carbon tube |
| CN1712349A (en) * | 2004-06-15 | 2005-12-28 | 南开大学 | Arc synthesis of single-wall carbon nanometer tubes |
| CN1749156A (en) * | 2005-10-18 | 2006-03-22 | 南开大学 | Arc method for synthesizing controllable single wall carbon nano tube |
| CN1887701A (en) * | 2006-07-21 | 2007-01-03 | 太原理工大学 | Process of preparing single-wall carbon nanotube |
Non-Patent Citations (1)
| Title |
|---|
| LV，X;PU,F;MA,YF;ET AL.: "Synthesis of high quality single-walled carbon nanotubes at large scale by electric arc using metal compounds", CARBON * |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102179257A (en) * | 2011-04-15 | 2011-09-14 | 上海大学 | Preparation method of electro-catalyst of single-walled carbon nanotube loading platinum base for fuel cell |
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