CN1877774A

CN1877774A - Linear nano carbon tube composite-field emission source and method for preparing same and dedicated device therefor

Info

Publication number: CN1877774A
Application number: CN 200610081052
Authority: CN
Inventors: 冯孙齐
Original assignee: BEIJING HANNA NANO-TECH Co Ltd
Current assignee: Beijing Peking University New Century Science And Technology Development Co ltd
Priority date: 2005-06-03
Filing date: 2006-05-23
Publication date: 2006-12-13
Anticipated expiration: 2026-05-23
Also published as: CN100423162C

Abstract

The invention discloses a linear nanometer carbon pipe composite field launching source and making method and specific device, which contains a conductive fiber weaving line substrate with single wall or multiple-wall nanometer carbon pipe film deposited on the substrate. The making method comprises the following steps: predisposing the surface of fiber weaving line; utilizing self-power pyrolytic CVD method grow single-wall or multiple-wall nanometer carbon pipe on the fiber weaving fiber. The length of composite field launching source is not limited, which produces linear pattern product. The device is fit for pipe-typed nanometer carbon pipe field launching luminous bulb, which can observe the field emitting condition.

Description

Compound field emission source of a kind of linear nano carbon tube and preparation method thereof and isolated plant

Technical field

The present invention relates to compound field emission source of a kind of CNT (carbon nano-tube) (Carbon Nanotubes is hereinafter to be referred as CNTs) and preparation method thereof and grower, particularly relate to compound field emission source of a kind of line style CNTs and preparation method thereof and isolated plant.

Background technology

CNTs can be considered the quasi-one-dimensional nanometer material that is curled and formed by graphite flake layer: the curling CNTs that forms is called Single Walled Carbon Nanotube (Single Walled Carbon Nanotubes by the mono-layer graphite sheet, hereinafter to be referred as SWNTs), the coaxial CNTs that forms that curls is called multiple-wall carbon nanotube (Multi-WalledCarbon Nanotubes is hereinafter to be referred as MWNTs) by the multilayer graphite flake.

Because CNTs has excellent electric conductivity (for metallicity CNTs), high mechanical strength and chemical stability, and very high form factor (ratio of length and radius), make it become desirable electron field emission materials, cause that people pay close attention to widely.

According to the electronic field emission principle, the projection of body surface can cause near the enhancing of the local electric field convex top, and field enhancement factor (β) is directly proportional with protruding height (h), is inversely proportional to the radius of curvature (r) of convex top, i.e. β ∝ h/r.The surface irregularity of carbon cloth, they itself are exactly a kind of good field emission source.Jo etc. (S.H.Jo, et al., Appl.Phys.Letters, 85 (2004) 810.) adopt Thermal CVD Method, and the formed compound field emission source of growth MWNTs shows high field enhancement factor β=1.88 * 10 on carbon cloth ⁴, than the high about order of magnitude of β value of SWNTs that on substrates such as Si or glass, grows or MWNTs film.Point out (J.Y.Huang, Z.F.Ren et a1., Appl.Phys.Letters, 87 (2005) 53110) such as nearest Huang, and the excellent field emission performance of the compound field emission source of CNT (carbon nano-tube) is caused by the multistage effect of field emission.

(comprising catalyse pyrolysis CVD and all kinds of plasma enhanced chemical vapor deposition-PECVD), is the three class common methods of preparation CNTs for arc process, laser method and chemical vapor deposition (CVD) method.Owing to can control effectively to the CVD process, people utilize the CVD method can not only prepared in batches high-purity SWNTs or MWNTs, and can prepare the orientation or the non-orientation CNTs film of diameter, length and controllable density on various substrates.

(J.-M.Bonard such as Bonard, et al., Appl.Phys.Letters 78 (2001) 2775) employing catalyse pyrolysis CVD method, growth CNTs makes line style CNTs field emission source on the Fe-Al-Cr alloy wire, and be used for the preparation of tubular type CNTs field emission light-emitting lamp, its concrete preparation process is as follows:

(1) with acetone and ethanol Fe-Al-Cr electrothermal alloy line (long 7cm, diameter 1mm) is carried out ultrasonic cleaning.

(2) alloy wire after will cleaning under 1000 ℃ in air oxidation processes 12 hours, form compact oxide (being mainly aluminium oxide) on the alloy wire surface.With the alloy silk immersion concentration after oxidation processes is the ferric nitrate (Fe (NO of 40mM ₃) ₃9H ₂O) in the ethanolic solution, on alloy wire, adhere to or deposit one deck iron-containing catalyst.Because compact oxidation layer has the height chemical inertness on the alloy wire, guarantee to be deposited on catalyst type and thickness on the alloy wire by change, control the growth of CNTs on alloy wire.

(3) alloy wire that will scribble catalyst places on the support in the horizontal pipe furnace, and furnace temperature is 720 ℃, feeds acetylene/nitrogen mixture gas in the stove, and acetylene and nitrogen flow rate are respectively 20mL/min and 80mL/min, and the stove internal gas pressure is 1 atmospheric pressure.The acetylene gas catalytic decomposition forms a large amount of carbon atoms under high temperature (720 ℃), forms CNTs by carbon atom in diffusion-deposition process of catalyst particles intragranular, makes line style CNTs field-transmitting cathode.

(4) long be evaporation layer of transparent electroconductive ITO film on the glass tube inwall of 4cm for 5cm, diameter, and then on electrically conducting transparent ITO film, cover phosphor powder layer and make anode.The line cathode that is coated with catalyst layer is installed in the center of glass tube anode, vacuumizes (10 after the sealing ^-6～10 ^-7Torr); When adding 5.4kV voltage between negative electrode and anode, the cathodic field emission is 0.5mA/cm ²Fluorescent material on the anode is subjected to the field emission electron bombardment and luminous, and brightness can reach 10 ⁴Cd/m ²

When preparing line style CNTs field emission source with above-mentioned conventional tubular stove Thermal CVD Method, the flat-temperature zone length of tube furnace should be greater than line style CNTs field emission source length; Therefore, it only is suitable for preparing short (the line style CNTs field emission source for example＜10cm) of length.With tube furnace CVD method prepare length bigger (line style CNTs field emission source for example＞10cm) needs to adopt the very long tube furnace of boiler tube, and equipment investment cost and power consumption are increased.

Summary of the invention

Main purpose of the present invention is in order to prepare the compound field emission source of novel C NTs, and CNT (carbon nano-tube) is grown on the conductive fiber kernmantle substrate, forms the compound CNTs field emission source of line style.

Another object of the present invention provides a kind of method and isolated plant for preparing the compound field emission source of above-mentioned line style CNTs, adopts from the Thermal CVD Method of the switching on CNTs that grows on the fibrage rope.

The compound field emission source of line style CNTs provided by the invention comprises substrate and CNT (carbon nano-tube); It is characterized in that: described substrate is the fibrage rope, and the diameter of fibrage rope is 0.5-3mm, and length is 10-180cm; Wherein the fibre diameter of fibrage rope is 0.5-20 μ m; Described CNT (carbon nano-tube) is deposited on the fibrage rope, and depending on the growth conditions CNT (carbon nano-tube) can be SWNTs (diameter range is 0.7-2.2nm, and length is 1-25 μ m), also can be MWNTs (diameter range is 5-30nm, and length range is 1-25 μ m).

In above-mentioned technical scheme, described fibrage rope comprises carbon fiber knit rope, Fe-Al-Cr alloy fiber kernmantle and stainless steel fibre kernmantle.

Isolated plant provided by the invention is as depicted in figs. 1 and 2: device shown in Figure 1 can be used for adopting from the Thermal CVD Method of switching on and prepares the compound field emission source of CNT (carbon nano-tube), also can be used for the field emission characteristic and the characteristics of luminescence of the compound field emission source of in-situ test; Even energy limit growth CNTs, the field emission of CNTs is observed on the limit, by the variation that launch CNTs growth course midfield, understands growth course and the mechanism of CNTs.Device shown in Figure 2 is the simplification of device shown in Figure 1, and it only can be used for preparing the compound field emission source of CNT (carbon nano-tube) by the Thermal CVD process of switching on certainly.

Device shown in Figure 1 is mainly by reative cell, form from a power circuit and a transmission test loop.

Reative cell is mainly become with the gas circuit set of systems by glass tube 1, first loam cake 2, first lower cover 4, and the sealing of reative cell realizes by upper and lower " O " type rubber seal 6 and the 7 and first needle point valve 8 and the second needle point valve 9.Be separately installed with air inlet and chew 12 and bleed and chew 13 on first loam cake 2 and first lower cover 4, air inlet is chewed 12 and is linked to each other with mass-flow gas meter and work source of the gas 14 by the first needle point valve 8, bleeds to chew 13 and pass through the second needle point valve 9 and link to each other with vacuum pump system 15; Mass-flow gas meter and work source of the gas 14, the first needle point valve 8, the second needle point valve 9, air inlet chew 12, bleed and chew 13 and the air-channel system of vacuum pump system anabolic reaction chambers 15.By tightening screw 31, first lower cover 4 can be fixed on the experiment porch 32.

From power circuit mainly by power supply DC ₁, conductive fiber kernmantle 16 and go up binding post 10 and following binding post 11 compositions; DC power supply DC ₁Positive and negative electrode link to each other K switch with last binding post 10 with following binding post 11 respectively ₁Can control from the conducting of power circuit or open circuit.Conductive fiber kernmantle 16 surface coverage have catalyst layer 17, the upper end of kernmantle links to each other with last binding post 10, the lower end links to each other with following binding post 11 with spring 19 by anchor clamps 18, and spring 19 can compensate the dilatancy of conductive fiber kernmantle 16 because of causing from the energising heating; Upper and lower

ceramic insulation cover

20 and 21 makes upper and lower binding

post

10,11 and first upper and

lower cover

2 and 4 keep insulation respectively.

Transmission test loop, field is mainly by DC power supply DC ₂, anode and negative electrode form DC power supply DC ₂Negative pole link to each other with conductive fiber kernmantle 16 (as negative electrode) by last binding post 10, the positive pole of power supply passes through first loam cake 2 and links to each other K switch with electrically conducting transparent ITO film 23 (as anode) ₂Can control the conducting of test loop or open circuit.Utilize test loop can measure the field emission characteristic curve of CNTs film, and can measure the characteristics of luminescence that field emission electron impact fluorescence powder causes.That ceramic insulation cover 23 and 24 makes is separate from a power circuit and a transmission test loop, do not disturb mutually, and they can distinguish separately or move simultaneously.

Described glass tube is homemade T type fluorescent tube, and the length of glass tube is 10-180cm, and diameter is 3-8cm, and wall thickness is 0.8-3.0mm.Be coated with layer of transparent electroconductive ITO film 23 on the glass tube inwall, on electrically conducting transparent ITO film 23, deposit phosphor powder layer 24; Glass tube, electrically conducting transparent ITO film 23 and phosphor powder layer 24 are formed an anode of emission; The electrically conducting transparent ITO film 23 and first loam cake 2 or first lower cover 4 keep good electrical contact.

The preparation method of described electrically conducting transparent ITO film 23 comprises sol-gel extraction, electron-beam vapor deposition method, spray pyrolysis and magnetron sputtering method, and the thickness range of gained electrically conducting transparent ITO film 23 is 200-500 μ m.

Described fluorescent material adopts homemade FED series three primary colors fluorescent powder, day inferior NP1045 white fluorescent powder and Osram-P22 green emitting phosphor, and adopting electrophoresis deposit thickness on the electrically conducting transparent ITO of glass tube inwall film 23 is 10-30 μ m phosphor powder layer 24.

Be processed with annular upper and lower bulge loop 27 and 28 respectively being processed with respectively on annular upper and

lower groove

25 and 26, the second upper and lower covers 3 and 5 on first upper and

lower cover

2 and 4 of described device.With upper and lower " O "

type rubber seal

6 and 7 and the two ends of glass tube put into upper and

lower groove

25 and 26 respectively, and upper and lower bulge loop 27 and 28 is embedded respectively in the corresponding groove.After first, second

needle point valve

8,9 is closed, by tightening upper and

lower screw

29 and 30, make upper and lower bulge loop 27 and 28 displacements, force upper and lower " O "

type rubber seal

6 and 7 distortion, thus the sealing of realization response chamber.

Described first upper and

lower cover

2 and 4, second upper and lower cover 3 and 5, upper and lower binding

post

10 and 11, anchor clamps 18, spring 19, upper and lower bulge loop 27 and 28,

screw

29,30 and 31, air inlet chew 12 and bleed and chew 13 and all adopt stainless steel to make.

Described DC power supply DC ₁Big direct current can be provided, make the conductive fiber kernmantle from the energising heating; Can from the catalyst layer on covering fibrage rope 16 17, grow CNTs film 22 under certain condition, make the compound field emission source of line style CNTs.Power supply in power circuit also can use the AC power that low-voltage, high-current can be provided.

Device shown in Figure 1 can be simplified by a cancellation transmission test loop; This moment, electrically conducting transparent ITO film 23 and phosphor powder layer 24 also can be cancelled, and the device after the simplification as shown in Figure 2.The function of this simplification device only limits to prepare compound field emission source, so glass tube can use metal (for example stainless steel or aluminium) pipe or vacuum ceramic pipe to substitute.

The preparation method of the compound field emission source of a kind of line style CNTs provided by the invention may further comprise the steps:

(1) select fibrage rope substrate: alternative condition is: (1) fiber is necessary for conductor, (2) fiber must be able to tolerate the required high temperature (650-1000 ℃) of growth CNTs, (3) fiber diameter range is 1-20 μ m, to guarantee that fibrous braid itself has higher field enhancement factor, (4) fiber should have good chemical inertness, so that can cover catalyst type and thickness on the fibrage rope by change, control the parameters such as density, length and diameter of CNTs.

(2) preliminary treatment of fibrage rope: before growth CNTs on the fibrage rope, must carry out cleaning surfaces to it and handle, under needs and possible condition, carry out surface oxidation treatment and at the surface deposition catalyst layer.

(3) with the CNTs that on the fibrage rope, grows from the Thermal CVD Method of switching on: will be fixed in the device by mode shown in Figure 1 through pretreated fibrage rope.The method of growth CNTs is as follows:

Therefore (1) the fibrage rope degass: the fibrage rope has very big surface area, is adsorbed with a large amount of gas molecules, particularly oxygen molecule, should carry out the processing of degassing of fibrage rope before growth CNTs.

(2) catalyst reduction is handled: in order to improve catalyst activity, promote the growth of CNTs, before growth CNTs catalyst is reduced processing usually.

(3) the energising Thermal CVD certainly of CNTs growth: on the fibrage rope surface after above-mentioned processing, form a large amount of active very strong catalyst nano particles, under the hot conditions of energising heating certainly, carbonaceous gas decomposes at the catalyst nano particle surface, generates CNTs by diffusion-deposition process.

In technique scheme, according to the selected fibrage rope of fibrage rope alternative condition be: carbon fiber knit rope, Fe-Al-Cr alloy fiber kernmantle and stainless steel fibre kernmantle.Carbon fiber can satisfy whole four conditions, and Fe-Al-Cr alloy and stainless steel fibre can satisfy the first three items requirement undoubtedly.Through the Fe-Al-Cr of oxidation processes alloy fiber surface one deck compact oxide (being mainly aluminium oxide) is arranged, make it have good chemical inertness; Therefore, Fe-Al-Cr alloy fiber kernmantle is one of good line style backing material.Therefore the oxide layer of stainless steel fibre itself has catalytic performance, says strictly that it can not satisfy the 4th requirement.But because the stainless steel fibre low price, be easy to obtain, and stainless steel is often used as the backing material of growing nano carbon pipe, so it also can be used as the candidate of substrate.

In technique scheme, described clean is selected fibrage rope to be put into acetone or alcohol carry out ultrasonic cleaning; The surface oxidation treatment condition of described Fe-Al-Cr alloy is: under 600-1100 ℃ in air oxidation 5-15 hour;

In technique scheme, the method for described fibrage rope surface deposition catalyst comprises chemical method and physical method:

(a) chemical method: the custom catalysts of growth CNTs is magnesium-yttrium-transition metals such as Fe, Ni, Co and Mo, and the inorganic or organic compound that therefore contains above-mentioned metallic element all can be elected to be catalyst, for example can select nine nitric hydrate iron Fe (NO ₃) ₃9H ₂O, Nickelous nitrate hexahydrate Ni (NO ₃) ₂6H ₂O, cabaltous nitrate hexahydrate Co (NO ₃) ₂6H ₂O; Iron(III) chloride hexahydrate FeCl ₃6H ₂O, six hydration Nickel Chloride NiCl ₂6H ₂O; The ferrous C of two oxalic acid hydrates ₂FeO ₄2H ₂O, two oxalic acid hydrate nickel C ₂NiO ₄2H ₂O, Diaquaoxalato cobalt C ₂CoO ₄2H ₂O; Four ferric sulfate hydrate Fe ₂(SO ₄) ₃4H ₂O, four molybdic acid hydrate ammonia (NH ₄) 6Mo ₇O ₂₄4H ₂O, ferritin etc.Concrete experimental technique is as follows: at first prepare the aqueous solution or the ethanolic solution of above-claimed cpd, wherein the concentration of catalyst metals is 1-100mM; After prepare solution left standstill 1-12 hour, soak in the solution for preparing 3-120 second immersing through pretreated fibrage rope, take out the back and redundant solution is blown off with nitrogen, can carry out subsequent treatment after to be dried.By the molar concentration of regulator solution, can change the thickness of deposited catalyst film.

(b) physical method: utilize electron-beam vapor deposition method or magnetron sputtering method, the magnesium-yttrium-transition metal film that the about 1-20nm of deposition is thick on the fibrage rope is as catalyst layer.

In technique scheme, the described fibrage rope step of degassing is as follows: at first close air inlet and chew 8 needle point valve 29, opening bleeds chews 10 needle point valve 31, starts vacuum pump system (mechanical pump and molecular pump); Vacuum reaches 10 in glass tube ^-6-10 ^-7Behind the Torr, connect from switching on the heating circuit electric current, the fibrage rope is heated to 600-700 ℃ and keep 10-15min, the fibrage rope is degassed.

In technique scheme, described catalyst reduction treatment step is as follows: regulate the electric current in power circuit, make the kernmantle temperature remain on 600-700 ℃.Subsequently, closure molecule pump (mechanical pump is operate as normal still) feeds in reative cell by what hydrogen or ammonia and carrier gas (argon or nitrogen) were formed and mixes reducing gas.Regulate needle point valve and mass-flow gas meter, reducing gas flow velocity and flow rate of carrier gas are controlled at respectively in 10-50sccm and 100-300sccm (sccm the is the per second cubic centimetre) scope, and the reative cell internal gas pressure is remained in the 40-300mbar scope.After the 15-30min reduction is handled, activity of such catalysts will obviously be strengthened.

In technique scheme, described CNTs growth step is as follows: regulate the electric current in power circuit, make the kernmantle temperature remain on 650-1000 ℃.Feed the working gas of being made up of carbonaceous gas and carrier gas to reative cell, carbonaceous gas is methane, ethane, acetylene, ethene or carbon monoxide CO gas, and carrier gas is nitrogen or argon; Regulate needle point valve and mass flowmenter, carbonaceous gas flow velocity and flow rate of carrier gas are controlled at respectively in 10-50sccm and the 100-300sccm scope, and to make the working gas air pressure range be 40-300mbar.Under these conditions, the CNTs growth time is about 1-30min.By cutting off from electrical current or closing air inlet needle point valve (supply of the gas that quits work), can stop the growth of CNTs.

After adopting technique scheme to finish the growth of CNTs, also can utilize the test loop in the device shown in Figure 1, carry out the test of the field emission characteristic and the characteristics of luminescence.Concrete steps are as follows: cutting off behind the power circuit electric current, close air inlet needle point valve and open molecular pump, the indoor vacuum of question response reaches 10 ^-6-10 ^-7Behind the Torr, connect test loop.When the voltage between negative electrode (the compound field emission source of line style CNTs) and the anode (being made up of glass tube, electrically conducting transparent ITO film and phosphor powder layer) reaches field emission cut-in voltage, ammeter A ₂Display field is launched firing current.Improve with voltage, an emission current increases, the emission I-V curve of can showing up thus.When emission current is enough big, can observe with the naked eye light-emitting phosphor then and there, and with the apparatus measures characteristics of luminescence (brightness and uniformity).Under certain test conditions, utilize this device can realize limit growth CNTs, the limit is measured field emission characteristic and is observed an image of emission, and this growth and emission mechanism to further investigation CNTs is significant.

Advantage of the present invention:

(1) compound field emission source of the present invention is made up of conductive fiber kernmantle and CNTs, and the compound field emission source of this line style has excellent field emission characteristic; Lamp is launched in the tubular type field that utilizes it to make, and has advantages such as not mercurous, little, the no stroboscopic of energy consumption, brightness height and life-span length.

(2) isolated plant provided by the invention can be used for employing and prepare the compound field emission source of CNT (carbon nano-tube) from the Thermal CVD Method of switching on, and also can be used for the field emission characteristic and the characteristics of luminescence of the compound field emission source of in-situ test; Even energy limit growth CNTs, the field emission of CNTs is observed on the limit.

(3) the compound field emission source of line style CNTs of the present invention adopts from the Thermal CVD Method preparation of switching on, so its length is unrestricted; Characteristics such as this preparation method and device have structure and technology is simple, power consumption is little, investment and production cost are low.

Description of drawings

Fig. 1 is the device schematic diagram of the compound field emission source of preparation line style CNTs, and it both can be used for preparing the compound field emission source of CNTs, can be used for the field emission characteristic and the characteristics of luminescence of test compound field emission source again.Fig. 2 is the simplification device of Fig. 1, and it only can be used to prepare the compound field emission source of CNTs.DC wherein ₁Be the DC power supply from power circuit, A ₁, V ₁And K ₁Be respectively ammeter, voltmeter and switch from power circuit; DC ₂Be the DC power supply in transmission test loop, field, A ₂, V ₂And K ₂Be respectively ammeter, voltmeter and the switch of test loop.

Number designation representative among the figure:

1. cylinder type cavity 2. first loam cakes 3. second loam cakes

4. " O " type rubber seal on first lower cover, 5. second lower covers 6.

7. following " O " type rubber seal 8. first needle point valves 9. second needle point valves

10. going up 11. times binding post 12. air inlets of binding post chews

Chew 14. mass flowmenters and work source of the gas 15. vacuum pump systems 13. bleed

16. conductive fiber kernmantle 17. catalyst layers 18. anchor clamps

19. 21. times insulating cases of insulating case on the spring 20.

22. nano-sized carbon periosteum 23. electrically conducting transparent ITO films 24. phosphor powder layers

25. bulge loop on last groove 26. lower groove 27.

28. lower convex ring 29. screws 30. screws

31. screw 32. experiment porchs

Embodiment

Below in conjunction with embodiment and Fig. 1 the present invention is described in further detail.

Embodiment 1

Present embodiment is that this device both can be used for preparing the compound field emission source of line style CNTs, can be used for testing the field emission characteristic and the characteristics of luminescence of the compound field emission source of line style CNTs again to the description of the isolated plant of as shown in Figure 1 the compound field emission source of preparation line style CNTs.For the clear structure that shows line style CNTs field emission source, in Fig. 1, separate catalyst film on the fibrage rope 16 17 and nano-sized carbon periosteum 18 a bit of respectively downward or upward.Device shown in Figure 1 is by reative cell, form from a power circuit and a transmission test loop.

Reative cell by cylinder type cavity 1, first and second loam cakes 2 and 3, first and second

lower covers

4 and 5 and air-channel system form.Cylinder type cavity 1 is homemade T type fluorescent tube, and its length is 10cm, and diameter is 3cm, and wall thickness is 0.8mm.With colloidal sol-gel extraction deposit thickness on glass tube 1 inwall is the electrically conducting transparent ITO film 23 of 200nm, and its light transmission rate is greater than 90%, and resistivity is about 1.7 * 10 ^-2(corresponding square resistance is 350 Ω/) to Ω-cm.Fluorescent material adopts day NP1045 type white emitting fluorescent powder of inferior (Nichia) company production, is the phosphor powder layer 24 of 10 μ m with electrophoresis deposit thickness on electrically conducting transparent ITO film 23.

On first loam cake 2 and first lower cover 4, be processed with annular upper and

lower groove

25 and 26 respectively, on second loam cake 3 and second lower cover 5, be processed with annular upper and lower bulge loop 27 and 28 respectively.With upper and lower " O "

type rubber seal

6 and 7 and the two ends of glass tube, put into upper and

lower groove

25 and 26 respectively, and upper and lower bulge loop 27 and 28 is embedded respectively in upper and lower groove 25 and 26.Close the first and second

needle point valves

8 and 9, and, make upper and lower bulge loop 27 and 28 displacements, force upper and lower " O "

type rubber seal

6 and 7 distortion by tightening

screw

29 and 30, and the sealing of realization response chamber.

On first loam cake 2 binding post 10 is being installed also and air inlet chews 12, binding post 11 is installed on first lower cover 4 down and is bleeding and chew 13; Upper and lower

ceramic insulation cover

20 and 21 is set in outside

binding post

10 and 11, makes upper and lower

binding post

10 and 11 keep electric insulation with first loam cake 2 and first lower cover 4 respectively.

First, second loam cake 2 and 3, first, second

lower cover

4 and 5, upper and lower bulge loop 27 and 28, upper and lower

binding post

10 and 11, anchor clamps 18, spring 19,

screw

29,30 and 31, air inlet chew 12 and bleed and chew 13 and all make of stainless steel.

The glass tube 1 of described reative cell adopts homemade T type fluorescent tube, and its length is 10cm, and diameter is 3cm, and wall thickness is 0.8mm.With colloidal sol-gel extraction deposit thickness on glass tube 1 inwall is the electrically conducting transparent ITO film 23 of 200nm, and its light transmission rate is greater than 90%, and resistivity is about 1.7 * 10 ^-2(corresponding square resistance is 350 Ω/) to Ω-cm.Fluorescent material adopts day NP1045 type white emitting fluorescent powder of inferior (Nichia) company production, is the phosphor powder layer 24 of 10 μ m with electrophoresis deposit thickness on electrically conducting transparent ITO film 23.

Described conductive fiber kernmantle 16 is a Fe-Al-Cr alloy fiber kernmantle, and its length is 10cm, and diameter is 0.5mm, and fibre diameter is 0.5 μ m.Fe-Al-Cr alloy fiber kernmantle surface is after cleaning and oxidation processes, and deposited by electron beam evaporation method deposit thickness is the Fe catalyst layer of 10nm.

Air inlet is chewed 12 and is connected by needle point valve 8 and mass flowmenter and work source of the gas (comprising carbon-source gas, reducing gas and carrier gas) 14; Bleed and chew 11 and link to each other with vacuum pump system (comprising mechanical pump and molecular pump) 15 by needle point valve 9.

This device has two cover power circuits, and as shown in Figure 1, wherein the right side is from power circuit, and the left side is a transmission test loop:

From power circuit mainly by DC power supply DC ₁, go up binding post 10, binding post 11 and the conductive fiber kernmantle 16 that is coated with catalyst film 17 are formed down.DC power supply DC ₁Negative pole by ammeter A ₁Link to each other with last binding post 10, positive pole links to each other with following binding post 11; The upper end that is coated with the conductive fiber kernmantle 16 of catalyst film 17 links to each other with last binding post 10, and its lower end links to each other with following binding post 11 with spring 19 by anchor clamps 18, and spring 19 can compensate the dilatancy of conductive fiber kernmantle 16 because of causing from the energising heating.DC power supply DC ₁The big electric current that provides can make conductive fiber kernmantle 16 from the energising heating; Grow CNTs film 22 in the catalyst film 17 that can on fibrage rope 16, cover under certain condition, make the compound field emission source of line style CNTs.

Test loop is mainly by DC power supply DC ₂, negative electrode (the compound field emission source of line style CNTs) and anode (glass tube of band electrically conducting transparent ITO film 23 and phosphor powder layer 24) form.DC power supply DC ₂Voltage variable, its numerical value is by voltmeter V ₂Indication, the field emission current in the loop is by ammeter A ₂Indication.DC power supply DC ₂Negative pole link to each other with last binding post 10, anodal link to each other with electrically conducting transparent ITO film 23 by first loam cake 2 or first lower cover 4.That upper and lower

ceramic insulation cover

20 and 21 makes is separate from power circuit and test loop, do not disturb mutually, and they can distinguish separately or move simultaneously.Utilize test loop can measure the field emission I-V curve and the characteristics of luminescence (brightness and uniformity) of the compound field emission source of line style CNTs.

Embodiment 2

In the device of present embodiment, cylinder type cavity 1 adopts homemade T type fluorescent tube, and its diameter is 3cm, and wall thickness is 1.2mm, and length is 30cm.Applying thick on the glass tube inwall with colloidal sol-gel extraction is the electrically conducting transparent ITO film of 200m, and deposits a day inferior NP1045 white fluorescent bisque with electrophoresis on electrically conducting transparent ITO film, and thickness is 20 μ m.Other parts of device are identical with embodiment 1.

The step of making the compound field emission source of line style CNTs is as follows:

(1) selection of fibrage rope and processing thereof: selecting a length is 30cm, diameter is that the Fe-Al-Cr alloy fiber kernmantle (fibre diameter is 1 μ m) of 0.5mm is as backing material, this Fe-Al-Cr alloy fiber kernmantle is put into acetone in proper order and ethanol carries out ultrasonic cleaning, oxidation 12 hours in air under 1000 ℃ then forms compact oxide at alloy surface.

(2) selection of catalysts and deposition process: on the Fe-Al-Cr of clean alloy fiber kernmantle, deposit thick Fe/Mo (1/1, the weight ratio) catalyst layer of one deck 15nm with magnetron sputtering method.With being coated with the Fe-Al-Cr alloy fiber kernmantle of catalyst, be installed in the experimental provision according to mode shown in Figure 1.

(3) with step from the Thermal CVD method growth CNTs that switches on:

(a) close air inlet needle point valve and unlatching vacuum pump system (mechanical pump and molecular pump), the reative cell vacuum is extracted into 10 ^-6Mbar; Connect subsequently from power circuit, the fibrage rope is heated to 600 ℃, kept 15 minutes, remove the air that adsorbs on the carbon fiber rope;

(b) closure molecule pump (mechanical pump is still in running order) feeds ammonia/nitrogen mixture gas to reative cell; Regulate needle point valve and mass-flow gas meter, the velocity ratio that makes ammonia and nitrogen is 10sccm/100sccm, and mixed gas pressure intensity is 100mbar; Under 600 ℃ of C, kept 15 minutes, catalyst is carried out activation processing;

(c) temperature is raised to 700 ℃, and, regulate needle point valve and mass-flow gas meter to reative cell feeding acetylene/nitrogen hybrid working gas, the velocity ratio that makes acetylene and nitrogen is 10sccm/100sccm, mixed gas pressure intensity is 100mbar, and the CNTs growth time is 5 minutes.After arriving predetermined growth time, cut-out is from the power circuit electric current and close air inlet needle point valve, and the CNTs growth is stopped;

(4) test of the field emission characteristic and the characteristics of luminescence: after obtaining the compound field emission source of line style CNTs, can carry out in-situ test to its field emission characteristic and the characteristics of luminescence, its step is as follows: when the vacuum of reative cell reaches 10 ^-6-10 ^-7Connect test loop behind the Torr, a record emission I-V curve in the process that increases voltage, and record luminance (brightness and the uniformity).If find that the field emission characteristic and the characteristics of luminescence are not ideal enough, can stop test, reclose from power circuit and gas circuit and make the CNTs continued growth; And then the checkout area emission characteristics and the characteristics of luminescence.So repeatedly till field emission characteristic and characteristics of luminescence satisfaction.

Embodiment 3

In the device of present embodiment, cylinder type cavity 1 adopts homemade T type fluorescent tube, and its diameter is 4cm, wall thickness 1.4mm, long 50cm.Applying thick on the glass tube inwall with colloidal sol-gel extraction is the electrically conducting transparent ITO film of 250nm.With electrophoresis deposition of thick on electrically conducting transparent ITO film is the phosphor powder layer of 30 μ m, and fluorescent material is German Osram-P22 type green light fluorescent powder.Other parts of device are identical with embodiment 1.

Introduce the step of utilizing present embodiment to make the compound field emission source of line style CNTs below:

(1) selection of fibrage rope and processing thereof: select long 50cm, the Fe-Al-Cr alloy fiber kernmantle of diameter 1.0mm (fibre diameter is 2 μ m) is as backing material, and press embodiment 2 described methods, Fe-Al-Cr alloy fiber kernmantle is cleaned and oxidation processes.

(2) selection of catalysts and covering method: preparation 20mM ferric nitrate Fe (NO ₃) ₃9H ₂O and 50mM aluminum nitrate Al (NO ₃) ₃9H ₂The ethanolic solution of O, wherein ferric nitrate is a catalyst, adds the gathering that aluminum nitrate can at high temperature stop catalyst granules.To in above-mentioned catalyst solution, soak 3 seconds through the Fe-Al-Cr of ultrasonic clean alloy fiber kernmantle, and take out subsequently and dry up with nitrogen.With the Fe-Al-Cr alloy fiber kernmantle of coating catalyst, be installed in the experimental provision according to mode shown in Figure 1.

(3) with step from the Thermal CVD method growth CNTs that switches on:

(a) at first, the reative cell vacuum is extracted into 10 ^-6Mbar, and energising is heated to 600 ℃ certainly, is incubated 15 minutes, removes the air that adsorbs on the Fe-Al-Cr alloy fiber kernmantle.

(b) then, closure molecule pump (mechanical pump is in running order), and feed hydrogen/argon mixture gas; By regulating needle point valve and mass-flow gas meter, the velocity ratio that makes hydrogen/argon gas is 15sccm/250sccm, and mixed gas pressure intensity is 150mbar.Kept 30 minutes down at 700 ℃, catalyst is carried out activation processing.

(c) last, temperature is raised to 720 ℃, introduce ethane C to reative cell ₂H ₆/ argon hybrid working gas, the velocity ratio of ethane and argon gas are 15sccm/250sccm, and mixed gas pressure intensity keeps 150mbar.The CNTs growth time is 10 minutes.

(4) method of testing of the field emission characteristic and the characteristics of luminescence is identical with embodiment 2.

Embodiment 4

In the device of present embodiment, cylinder type cavity 1 adopts homemade T type fluorescent tube, and its diameter is 4cm, wall thickness 1.4mm, long 70cm.Applying thick on the glass tube inwall with colloidal sol-gel extraction is the electrically conducting transparent ITO film of 250nm.With electrophoresis deposition of thick on electrically conducting transparent ITO film is the phosphor powder layer of 20 μ m, and fluorescent material is German Osram-P22 type green light fluorescent powder.Other parts of device are identical with embodiment 1.

(1) selection of fibrage rope and processing: select long 70cm, the Fe-Al-Cr alloy fiber kernmantle of diameter 1.0mm (fibre diameter is 4 μ m) is as backing material, and press embodiment 2 described methods, Fe-Al-Cr alloy fiber kernmantle is cleaned and oxidation processes.

(2) selection of catalysts and deposition process: prepare 500 μ g/mL ferritins and 60mM aluminum nitrate Al (NO ₃) ₃9H ₂The aqueous solution of O, wherein ferritin is a catalyst, adds the gathering that aluminum nitrate can at high temperature stop catalyst granules.The ghost that mammiferous ferritin is made up of 24 polypeptide chains, the about 5nm of this ghost internal diameter wherein accommodates the iron cluster that 3000 trivalent Fe atoms are formed.Therefore, ferritin can provide diameter little and uniform iron catalyst nano particle after oxidation, thereby can obtain the little and uniform SWNTs of diameter.To be placed in the above-mentioned catalyst solution and soak 5 seconds through the Fe-Al-Cr alloy fiber kernmantle after ultrasonic clean and the oxidation processes, take out the back and dry up with nitrogen.With the Fe-Al-Cr alloy fiber kernmantle of coating catalyst, be installed in the experimental provision according to mode shown in Figure 1, be about to the fibrage rope and be fixed between binding post 10 and the following binding post 11.

(3) with step from the Thermal CVD method growth CNTs that switches on:

(b) then, closure molecule pump (mechanical pump is in running order), and feed ammonia/nitrogen mixture gas; The velocity ratio that makes ammonia and nitrogen is 10scm/150sccm, and mixed gas pressure intensity is 40mbar.Kept 20 minutes down at 700 ℃, catalyst is carried out activity handle.

(c) last, temperature is raised to 720 ℃, introduce ethene C to reative cell ₂H ₄/ nitrogen hybrid working gas, the velocity ratio of ethene and nitrogen are 10sccm/150sccm, and mixed gas pressure intensity keeps 40mbar.The CNTs growth time is 10 minutes.

Embodiment 5

In the device of present embodiment, cylinder type cavity 1 adopts homemade T type fluorescent tube, and its diameter is 5cm, wall thickness 1.8mm, long 80cm.It is the electrically conducting transparent ITO film of 300nm that the deposited by electron beam evaporation sedimentation applies thick on the glass tube inwall.With electrophoresis deposition of thick on electrically conducting transparent ITO film is the phosphor powder layer of 10 μ m, and fluorescent material is homemade FED601 red fluorescence powder.Other parts of device are identical with embodiment 1.

(1) selection of fibrage rope and processing: select long 80cm, the carbon fiber knit rope of diameter 1.5mm (fibre diameter is 6 μ m) is as backing material, this carbon fiber knit rope put into acetone in proper order and ethanol carries out ultrasonic cleaning.

(2) selection of catalysts and covering method: preparation 20mM Diaquaoxalato cobalt C ₂CoO ₄2H ₂O and 20mM molybdenum acid ammonia (NH ₄) ₆Mo ₇O ₂₄4H ₂O and 40mM magnesium nitrate Mg (NO ₃) ₃9H ₂The aqueous solution of O, wherein cobalt oxalate and molybdenum acid ammonia are catalyst, add the gathering that magnesium nitrate can at high temperature stop catalyst granules.To in above-mentioned catalyst solution, soak 7 seconds through the stainless steel fibre kernmantle of ultrasonic clean, take out the back and dry up with nitrogen.With the stainless steel fibre kernmantle of deposited catalyst, be installed in the experimental provision according to mode shown in Figure 1.

(3) with step from the Thermal CVD method growth CNTs that switches on:

(a) at first, the reative cell vacuum is extracted into 10 ^-6Mbar, and energising is heated to 650 ℃ certainly, is incubated 15 minutes, removes the air that adsorbs on the stainless steel fibre kernmantle.

(b) then, closure molecule pump (mechanical pump is in running order), and feed hydrogen/nitrogen mixture gas; By regulating needle point valve and mass-flow gas meter, the velocity ratio that makes hydrogen/nitrogen is 10sccm/100sccm, and mixed gas pressure intensity is 100mbar.Kept 30 minutes down at 650 ℃, catalyst is carried out activity handle.

(c) last, temperature is raised to 1000 ℃, introduce CO/ nitrogen hybrid working gas to reative cell, the velocity ratio of CO and nitrogen is 10sccm/100sccm, mixed gas pressure intensity keeps 100mbar.The CNTs growth time is 20 minutes.

Embodiment 6

In the device of present embodiment, cylinder type cavity 1 adopts homemade T type fluorescent tube, and its diameter is 5cm, wall thickness 1.8mm, long 90cm.It is the electrically conducting transparent ITO film of 300nm that the deposited by electron beam evaporation sedimentation applies thick on the glass tube inwall.With electrophoresis deposition of thick on electrically conducting transparent ITO film is the phosphor powder layer of 20 μ m, and fluorescent material is homemade FED621 red fluorescence powder.Other parts of device are identical with embodiment 1.

(1) selection of fibrage rope and processing: select long 90cm, the carbon fiber knit rope of diameter 1.5mm (fibre diameter is 8 μ m) is as backing material, this carbon fiber knit rope put into acetone in proper order and ethanol carries out ultrasonic cleaning.

(2) selection of catalysts and covering method: preparation 20mM Diaquaoxalato cobalt C ₂CoO ₄2H ₂O and 30mM molybdenum acid ammonia (NH ₄) ₆Mo ₇O ₂₄4H ₂O and 50mM magnesium nitrate Mg (NO ₃) ₃9H ₂The aqueous solution of O, wherein cobalt oxalate and molybdenum acid ammonia are catalyst, add the gathering that magnesium nitrate can at high temperature stop catalyst granules.To in above-mentioned catalyst solution, soak 10 seconds through the carbon fiber knit rope of ultrasonic clean, take out the back and dry up with nitrogen.With the carbon fiber knit rope of deposited catalyst, be installed in the experimental provision according to shown in Figure 2.

(3) with step from the Thermal CVD method growth CNTs that switches on:

(a) at first, the reative cell vacuum is extracted into 10 ^-6Mbar, and energising is heated to 650 ℃ certainly, is incubated 12 minutes, removes the air that adsorbs on the carbon fiber knit rope.

(c) last, temperature is raised to 900 ℃, introduce CO/ nitrogen hybrid working gas to reative cell, the velocity ratio of CO and nitrogen is 10sccm/100sccm, mixed gas pressure intensity keeps 200mbar.The CNTs growth time is 20 minutes.

Embodiment 7

In the device of present embodiment, cylinder type cavity 1 adopts homemade T type fluorescent tube, and its diameter is 6.0cm, wall thickness 2.2mm, long 100cm.Applying thick on the glass tube inwall with spray pyrolysis is the electrically conducting transparent ITO film of 350nm.With electrophoresis deposition of thick on electrically conducting transparent ITO film is the phosphor powder layer of 30 μ m, and fluorescent material is homemade FED511 green emitting phosphor.Other parts of device are identical with embodiment 1.

(1) selection of fibrage rope and processing: select long 100cm, the carbon fiber knit rope of diameter 2.0mm (fibre diameter is 10 μ m) is as backing material, this carbon fiber knit rope put into acetone in proper order and ethanol carries out ultrasonic cleaning.

(2) selection of catalysts and covering method: preparation 30mM four ferric sulfate hydrate Fe ₂(SO ₄) ₃4H ₂O and 40mM Ammonium Molybdate Tetrahydrate (NH ₄) ₆Mo ₇O ₂₄4H ₂O and 60mM magnesium nitrate hexahydrate Mg (NO ₃) ₃6H ₂The aqueous solution of O, wherein ferric sulfate and ammonium molybdate are catalyst, add the gathering that magnesium nitrate can at high temperature stop catalyst granules.To in above-mentioned catalyst solution, soak 20 seconds through the carbon fiber knit rope of ultrasonic clean, take out the back and dry up with nitrogen.With the carbon fiber knit rope of deposited catalyst, be installed in the experimental provision according to shown in Figure 1.

(3) with step from the Thermal CVD method growth CNTs that switches on:

(b) then, closure molecule pump (mechanical pump is in running order), and feed ammonia/nitrogen mixture gas; By regulating needle point valve and mass-flow gas meter, the velocity ratio that makes ammonia and nitrogen is 50sccm/300sccm, and mixed gas pressure intensity is 100mbar, keeps 20 minutes down at 650 ℃, catalyst is carried out activity handle.

(c) last, temperature is raised to 950 ℃, feed methane CH to reative cell ₄/ nitrogen hybrid working gas, the velocity ratio 50sccm/300sccm of methane and nitrogen, mixed gas pressure intensity are 100mbar.The CNTs growth time is 30 minutes.

(4) test of the field emission characteristic and the characteristics of luminescence is identical with embodiment 2.

Embodiment 8

In the device of present embodiment, cylinder type cavity 1 adopts homemade T type fluorescent tube, and its diameter is 6.0cm, wall thickness 2.2mm, long 110cm.Applying thick on the glass tube inwall with spray pyrolysis is the electrically conducting transparent ITO film of 350nm.With electrophoresis deposition of thick on electrically conducting transparent ITO film is the phosphor powder layer of 15 μ m, and fluorescent material is homemade FED521 green emitting phosphor.Other parts of device are identical with embodiment 1.

(1) selection of fibrage rope and processing: select long 110cm, the stainless steel fibre kernmantle of diameter 2.0mm (fibre diameter is 12 μ m) is as backing material, this stainless steel fibre kernmantle put into acetone in proper order and ethanol carries out ultrasonic cleaning.

(2) selection of catalysts and covering method: prepare 400 μ g/mL ferritins and 30mM aluminum nitrate Al (NO ₃) ₃9H ₂The aqueous solution of O, wherein ferritin is a catalyst, adds the gathering that aluminum nitrate can at high temperature stop catalyst granules.To be placed on through the stainless steel fibre kernmantle of ultrasonic clean in the above-mentioned catalyst solution and soak 30 seconds, and take out the back and dry up with nitrogen.With the stainless steel fibre kernmantle of deposited catalyst, be installed in the experimental provision according to shown in Figure 1.

(3) with step from the Thermal CVD method growth CNTs that switches on:

(a) at first, the reative cell vacuum is extracted into 10 ^-6Mbar, and energising is heated to 650 ℃ certainly, is incubated 12 minutes, removes the air that adsorbs on the stainless steel fibre kernmantle.

(b) then, closure molecule pump (mechanical pump is in running order), and feed hydrogen/nitrogen mixture gas; By regulating needle point valve and mass-flow gas meter, the velocity ratio that makes hydrogen and nitrogen is 15scm/100sccm, and mixed gas pressure intensity is 40mbar.Kept 20 minutes down at 700 ℃, catalyst is carried out activation processing.

(c) last, temperature is raised to 950 ℃, feed ethene C to reative cell ₂H ₄/ nitrogen hybrid working gas, the velocity ratio 15sccm/150sccm of ethene and nitrogen, mixed gas pressure intensity are 40mbar.The CNTs growth time is 20 minutes.

Embodiment 9

In the device of present embodiment, cylinder type cavity 1 adopts homemade T type fluorescent tube, and its diameter is 7.0cm, wall thickness 2.6mm, long 120cm.Applying thick on the glass tube inwall with spray pyrolysis is the electrically conducting transparent ITO film of 400nm.With electrophoresis deposition of thick on electrically conducting transparent ITO film is the phosphor powder layer of 25 μ m, and fluorescent material is homemade FED531 green emitting phosphor.Other parts of device are identical with embodiment 1.

(1) selection of fibrage rope and processing: select long 120cm, the stainless steel fibre kernmantle of diameter 2.5mm (fibre diameter is 14 μ m) is as backing material, this stainless steel fibre kernmantle put into acetone in proper order and ethanol carries out ultrasonic cleaning.

(2) selection of catalysts and covering method: the ferrous C of preparation 20mM two oxalic acid hydrates ₂FeO ₄2H ₂O and 40mM two oxalic acid hydrate nickel C ₂NiO ₄2H ₂O and 50mM magnesium nitrate hexahydrate Mg (NO ₃) ₃6H ₂The aqueous solution of O, wherein ferrous oxalate and nickel oxalate are catalyst, add the gathering that magnesium nitrate can at high temperature stop catalyst granules.To in above-mentioned catalyst solution, soak 45 seconds through the carbon fiber knit rope of ultrasonic clean, take out the back and dry up with nitrogen.With the stainless steel kernmantle of deposited catalyst, be installed in the experimental provision according to shown in Figure 1.

(3) with step from the Thermal CVD method growth CNTs that switches on:

(b) then, closure molecule pump (mechanical pump is in running order), and feed hydrogen/nitrogen mixture gas; By regulating needle point valve and mass-flow gas meter, the velocity ratio that makes hydrogen and nitrogen is 50sccm/300sccm, and mixed gas pressure intensity is 100mbar, keeps 20 minutes down at 700 ℃, and catalyst is carried out activation processing.

(c) last, temperature is raised to 950 ℃, feed methane CH to reative cell ₄/ nitrogen hybrid working gas, the velocity ratio 50sccm/300sccm of methane and nitrogen, mixed gas pressure intensity are 100mbar.The CNTs growth time is 20 minutes.

Embodiment 10

In the device of present embodiment, cylinder type cavity 1 adopts homemade T type fluorescent tube, and its diameter is 7.0cm, wall thickness 2.6mm, long 140cm.Applying thick on the glass tube inwall with magnetron sputtering method is the electrically conducting transparent ITO film of 400nm.With electrophoresis deposition of thick on electrically conducting transparent ITO film is the phosphor powder layer of 35 μ m, and fluorescent material is homemade FED541 green emitting phosphor.Other parts of device are identical with embodiment 1.

(1) selection of fibrage rope and processing: select long 140cm, the stainless steel fibre kernmantle of diameter 2.5mm (fibre diameter is 16 μ m) is as backing material, this stainless steel fibre kernmantle put into acetone in proper order and ethanol carries out ultrasonic cleaning.

(2) selection of catalysts and covering method: preparation 80mM Iron(III) chloride hexahydrate FeCl ₃6H ₂O and 60mM aluminum nitrate Al (NO ₃) ₃9H ₂The ethanolic solution of O, wherein ferric trichloride is a catalyst, adds the gathering that aluminum nitrate can at high temperature stop catalyst granules.To in above-mentioned catalyst solution, soak 60 seconds through the stainless steel fibre kernmantle after ultrasonic clean and the oxidation processes, take out subsequently and dry up with nitrogen.With the stainless steel fibre kernmantle of deposited catalyst, be installed in the experimental provision according to shown in Figure 2.

(3) with step from the Thermal CVD method growth CNTs that switches on:

(a) at first, the reative cell vacuum is extracted into 10 ^-6Mbar, and energising is heated to 700 ℃ certainly, is incubated 10 minutes, removes the air that adsorbs on the stainless steel fibre kernmantle.

(b) then, closure molecule pump (mechanical pump is in running order), and feed hydrogen/argon mixture gas; By regulating needle point valve and mass-flow gas meter, the velocity ratio that makes hydrogen/argon gas is 20sccm/150sccm, and mixed gas pressure intensity is 300mbar, keeps 30 minutes down at 700 ℃, and catalyst is carried out activation processing.

(c) last, temperature is raised to 750 ℃, feed ethane C to reative cell ₂H ₆/ argon hybrid working gas, the velocity ratio of ethane and argon gas are 20sccm/150sccm, and mixed gas pressure intensity is 300mbar.The CNTs growth time is 15 minutes.

Embodiment 11

In the device of present embodiment, cylinder type cavity 1 adopts homemade T type fluorescent tube, and its diameter is 8.0cm, wall thickness 3.0mm, long 160cm.Applying thick on the glass tube inwall with magnetron sputtering method is the electrically conducting transparent ITO film of 450nm.With electrophoresis deposition of thick on electrically conducting transparent ITO film is the phosphor powder layer of 30 μ m, and fluorescent material is homemade FED401 blue colour fluorescent powder.Other parts of device are identical with embodiment 1.

(1) selection of fibrage rope and processing: select long 160cm, the Fe-Al-Cr alloy fiber kernmantle of diameter 3.0mm (fibre diameter is 18 μ m) is as backing material, and press embodiment 2 described methods, Fe-Al-Cr alloy fiber kernmantle is cleaned and oxidation processes.

(2) selection of catalysts and covering method: preparation 45mM four ferric sulfate hydrate Fe ₂(SO ₄) ₃4H ₂O and 45mM Nickelous nitrate hexahydrate Ni (NO ₃) ₂6H ₂O and 35mM magnesium nitrate Mg (NO ₃) ₃9H ₂The aqueous solution of O, wherein ferric sulfate and nickel nitrate are catalyst, add the gathering that magnesium nitrate can at high temperature stop catalyst granules.To in above-mentioned catalyst solution, soak 90 seconds through the Fe-Al-Cr of ultrasonic clean alloy fiber kernmantle, take out the back and dry up with nitrogen.With the Fe-Al-Cr alloy fiber kernmantle of deposited catalyst, be installed in the experimental provision according to shown in Figure 2.

(3) with step from the Thermal CVD method growth CNTs that switches on:

(a) at first, the reative cell vacuum is extracted into 10 ^-6Mbar, and energising is heated to 700 ℃ certainly, is incubated 10 minutes, removes the air that adsorbs on the Fe-Al-Cr alloy fiber kernmantle.

(b) then, closure molecule pump (mechanical pump is in running order), and feed hydrogen/nitrogen mixture gas; By regulating needle point valve and mass-flow gas meter, the flow-rate ratio that makes hydrogen and nitrogen is 10sccm/100sccm, and mixed gas pressure intensity is 100mbar, keeps 30 minutes down at 700 ℃, and catalyst is carried out activation processing.

(c) last, temperature is raised to 900 ℃, feed CO/ nitrogen hybrid working gas to reative cell, the velocity ratio 10sccm/100sccm of CO and nitrogen, mixed gas pressure intensity are 100mbar.The CNTs growth time is 25 minutes.

Embodiment 12

In the device of present embodiment, cylinder type cavity 1 adopts homemade T type fluorescent tube, and its diameter is 8.0cm, wall thickness 3.0mm, long 180cm.Applying thick on the glass tube inwall with magnetron sputtering method is the electrically conducting transparent ITO film of 500nm.With electrophoresis deposition of thick on electrically conducting transparent ITO film is the phosphor powder layer of 25 μ m, and fluorescent material is homemade FED411 blue colour fluorescent powder.Other parts of device are identical with embodiment 1.

(1) selection of fibrage rope and processing: select long 180cm, the Fe-Al-Cr alloy fiber kernmantle of diameter 3.0mm (fibre diameter is 20 μ m) is as backing material, and press embodiment 2 described methods, Fe-Al-Cr alloy fiber kernmantle is cleaned and oxidation processes.

(2) selection of catalysts and deposition process: preparation 60mM cabaltous nitrate hexahydrate Co (NO ₃) ₂6H ₂O and 40mM six hydration Nickel Chloride NiCl ₂6H ₂O and 65mM magnesium nitrate Mg (NO ₃) ₃9H ₂The aqueous solution of O, wherein cobalt nitrate and Nickel Chloride are catalyst, add the gathering that magnesium nitrate can at high temperature stop catalyst granules.To in above-mentioned catalyst solution, soak 120 seconds through the Fe-Al-Cr alloy fiber kernmantle after ultrasonic clean and the oxidation processes, take out the back and dry up with nitrogen.The Fe-Al-Cr alloy fiber of deposited catalyst is woven into rope, is installed in the experimental provision according to shown in Figure 2.

(3) with step from the Thermal CVD method growth CNTs that switches on:

(b) then, closure molecule pump (mechanical pump is in running order), and feed hydrogen/argon mixture gas; By regulating needle point valve and mass-flow gas meter, the velocity ratio that makes hydrogen and argon is 15sccm/250sccm, and mixed gas pressure intensity is 200mbar, keeps 25 minutes down at 700 ℃, and catalyst is carried out activation processing.

(c) last, temperature is raised to 1000 ℃, feed CO/ argon hybrid working gas to reative cell, the velocity ratio of CO and argon gas is 15sccm/250sccm, mixed gas pressure intensity is 200mbar.The CNTs growth time is 25 minutes.

Embodiment 13

The device of present embodiment as shown in Figure 2, the difference of it and Fig. 1 has been to cancel ITO film 23 and the phosphor powder layer 24 on a transmission test loop, cylinder type cavity 1 inwall; In the present embodiment, cylinder type cavity 1 adopts stainless steel tube (length is 50cm, and diameter is 4cm, and wall thickness is 1.0mm), and other apparatus structure is identical with embodiment 1.In the preparation process of the compound field emission source of line style CNTs, except that the test of the cancellation field emission characteristic and the characteristics of luminescence, other preparation process is all identical with embodiment 2.

Embodiment 14

The device of present embodiment removes cylinder type cavity 1 and adopts outside the aluminium-alloy pipe (length is 50cm, and diameter is 4cm, and wall thickness is 1.2mm), and other apparatus structure is identical with embodiment 13 with the step of the compound field emission source of preparation line style CNTs.

Embodiment 15

The device of present embodiment removes cylinder type cavity 1 and adopts outside the vacuum ceramic pipe (length is 50cm, and diameter is 3cm, and wall thickness is 1.2mm), and other apparatus structure is identical with embodiment 13 with the step of the compound field emission source of preparation line style CNTs.

Embodiment 16

The device of present embodiment removes cylinder type cavity 1 and adopts outside the homemade fluorescent tube (length is 10cm, and diameter is 3cm, and wall thickness is 1.4mm), and other apparatus structure is identical with embodiment 13 with the step of the compound field emission source of preparation line style CNTs.

Claims

1. compound field emission source of linear nano carbon tube, comprise substrate and CNT (carbon nano-tube), it is characterized in that, described substrate is the conductive fiber kernmantle: the diameter of described conductive fiber kernmantle and length are respectively 0.5-3mm and 10-180cm, and the fibre diameter in the described conductive fiber kernmantle is 0.5-20 μ m; Described CNT (carbon nano-tube) comprises that diameter and length are respectively the Single Walled Carbon Nanotube of 0.7-2.2nm and 1-50 μ m, and diameter and length are respectively the multiple-wall carbon nanotube of 540nm and 1-50 μ m.

2. by the compound field emission source of the described linear nano carbon tube of claim 1, it is characterized in that described conductive fiber kernmantle comprises: carbon fiber knit rope, Fe-Al-Cr alloy fiber kernmantle or stainless steel fibre kernmantle.

3. an isolated plant for preparing the compound field emission source of the described linear nano carbon tube of claim 1 comprises a reative cell, it is characterized in that, also comprises one from power circuit:

Described reative cell mainly is made up of cylinder type cavity (1), first loam cake (2), first lower cover (4) and the air-channel system that links to each other with cylinder type cavity (1), the sealing of reative cell realizes by upper and lower " O " type rubber seal (6) and (7) and the first and second needle point valves (8) and (9): be separately installed with binding post (10) and air inlet and chew (12) on first loam cake (2), be separately installed with down binding post (11) and bleed and chew (13) on first lower cover (4); Upper and lower ceramic insulation cover (20) and (21) make upper and lower binding post (10) and (11) keep electric insulation with first upper and lower cover (2) and (4) respectively; Air inlet is chewed (12) and is linked to each other by the first needle point valve (8) and mass-flow gas meter and the source of the gas (14) of working, and bleeds to chew (13) and pass through the second needle point valve (9) and link to each other with vacuum pump system (15); Mass-flow gas meter and work source of the gas (14), the first and second needle point valves (8) and (9), air inlet are chewed (12), are bled and chew the air-channel system of (13) and vacuum pump system (15) anabolic reaction chamber;

Described from power circuit mainly by power supply (DC ₁), conductive fiber kernmantle (16), go up binding post (10), binding post (11) is formed down; Conductive fiber kernmantle (16) surface coverage has catalyst layer (17), and the upper end of kernmantle (16) links to each other with last binding post (10), and the lower end links to each other with following binding post (11) with spring (19) by anchor clamps (18); DC power supply (DC ₁) positive and negative electrode be connected switch (K with last binding post (10) with following binding post (11) respectively ₁) control is from the conducting of power circuit or open circuit.

4. by the described device that is used to prepare the compound field emission source of linear nano carbon tube of claim 3, it is characterized in that, the sealing of reative cell realizes by upper and lower " O " type rubber seal (6) and (7) and the first and second needle point valves (8) and (9): be processed with annular respectively and go up groove (25) and annular lower groove (26) on the bottom surface of first loam cake (2) and first lower cover (4) end face, be processed with upper and lower bulge loop (27) and (28) respectively on the bottom surface of the end face of second loam cake (3) and second lower cover; Upper and lower " O " type rubber seal (6) and (7) tightly are enclosed within on the outer wall of two ends of cylinder type cavity (1), and they are put into upper and lower groove (25) and (26) respectively, make the inwall of cylinder type cavity (1) be close to the madial wall of upper and lower groove (25) and (26); Then upper and lower bulge loop (27) and (28) are embedded respectively in upper and lower groove (25) and (26), close first and second needle point valve (8) and (9), by tightening screw (29) and (30), upper and lower bulge loop (27) and (28) are moved, force upper and lower " O " type rubber seal (6) and (7) distortion, thus the sealing of realization response chamber.

5. by the described device that is used to prepare the compound field emission source of linear nano carbon tube of claim 3, it is characterized in that, described first upper and lower cover (2) and (4), upper and lower binding post (10) and (11), anchor clamps (18) and spring (19), air inlet chew (12), bleed and chew (13), upper and lower bulge loop (27) and (28), screw (29,30 and 31) and all make of stainless steel.

6. by the described device that is used to prepare the compound field emission source of linear nano carbon tube of claim 3, it is characterized in that described cylinder type cavity (1) is metal tube, vacuum ceramic pipe or glass tube, its length is 10-180cm, diameter is 3-8cm, and wall thickness is 0.8-3.0mm; Described metal tube is stainless steel tube or aluminium-alloy pipe.

7. by claim 3,4,5 or the 6 described devices that are used to prepare the compound field emission source of linear nano carbon tube, it is characterized in that, described cylinder type cavity (1) is a glass tube, and depositing thickness on its inwall successively is that 200-500 μ m electrically conducting transparent ITO film (23) and thickness are 10-30 μ m phosphor powder layer (24); Described fluorescent material is homemade FED series three primary colors fluorescent powder, day inferior NP1045 white fluorescent powder or Osram-P22 green emitting phosphor;

Also comprise a transmission test loop, it is by DC power supply DC ₂, anode and negative electrode form: anode is made up of glass tube (1), electrically conducting transparent ITO film (23) and phosphor powder layer (24), and when the realization response chamber sealed, assurance electrically conducting transparent ITO film had closely with first upper and lower cover (2) and (4) respectively and electrically contacts; Negative electrode is made up of conductive fiber kernmantle (16), catalyst layer (17) and nano-sized carbon periosteum (22), and conductive fiber kernmantle (16) is fixed between the upper and lower binding post (10 and 11), and keeps good electrical contact;

DC power supply DC ₂Negative pole by lead and last binding post (10) or down binding post (11) be connected DC power supply DC with negative electrode ₂First loam cake (2) or first lower cover (4) of positive pole by lead and conduction be connected switch (K with anode ₂) control test loop conducting or open circuit.

8. method for preparing the compound field emission source of linear nano carbon tube may further comprise the steps:

(a) select fibrage rope substrate: described fibrage rope is carbon fiber knit rope, Fe-Al-Cr alloy fiber kernmantle or stainless steel fibre kernmantle, and the length of kernmantle is 10-180cm, and diameter is 0.5-3mm, and fibre diameter is 0.5-20 μ m;

(b) preliminary treatment of fibrage rope: selected fibrage rope is put into acetone in order and ethanol carries out ultrasonic cleaning, adopt chemical method or physical method then, at the fibrage rope surface deposition catalyst rete after cleaning;

(c) in the isolated plant of the compound field emission source of preparation linear nano carbon tube, carry out the CNT (carbon nano-tube) growth: will be fixed between binding post (10) and the following binding post (11) through the pretreated fibrage rope of step (b); Open vacuum pump system (15), reach 10 when reative cell vacuumizes ^-6-10 ^-7During Torr, connect, make the fibrage rope be heated to 600-700 ℃, and keep 10-15min from power circuit; The electric current of adjusting in power circuit, when the temperature of conductive fiber kernmantle (16) reaches 650-1000 ℃, the working gas that feeding is made up of carbonaceous gas and carrier gas: the flow velocity of carbonaceous gas is 10-50sccm, flow rate of carrier gas is 100-300sccm, the reative cell internal gas pressure is 40-300mbar, and growth time is 1-30 minute.

9. press the preparation method of the compound field emission source of the described linear nano carbon tube of claim 8, it is characterized in that, also being included in the feeding working gas carries out before the growth of CNTs, feed reducing gas and carrier gas the catalyst layer on the fibrage rope is reduced processing: reduction temperature is 600-700 ℃, recovery time is 15-30min, the flow velocity of reducing gas is 10-50sccm, and flow rate of carrier gas is 100-300sccm, and pressure is 40-300mbar in the reative cell; Described reducing gas is hydrogen or ammonia, and described carrier gas is nitrogen or argon gas.

10. press the preparation method of the compound field emission source of the described linear nano carbon tube of claim 8, it is characterized in that, described Fe-Al-Cr alloy fiber kernmantle, after the ultrasonic cleaning and before the deposited catalyst film, under 900-1100 ℃ in air oxidation processes 8-15 hour.

11. preparation method by the compound field emission source of the described linear nano carbon tube of claim 8, it is characterized in that, the physical method of described deposited catalyst comprises: adopt electron beam evaporation or magnetically controlled sputter method, deposit thickness is the catalyst rete of 1-20nm on the fibrage rope, and described catalyst rete comprises Fe, Ni, Co or Mo magnesium-yttrium-transition metal.

12. preparation method by the compound field emission source of the described linear nano carbon tube of claim 8, it is characterized in that, the chemical method of described deposited catalyst rete, comprise the steps: at first, the aqueous solution or the ethanolic solution of preparation catalyst, wherein the concentration of catalyst metals is 1-100mM, and with solution left standstill 1-12 hour for preparing; Subsequently, soak in the solution for preparing 3-120 second, take out the back and blow drying with nitrogen off immersing through pretreated fibrage rope; Described catalyst rete comprises Fe, Ni, Co or Mo magnesium-yttrium-transition metal, and contains the inorganic or organic compound of Fe, Ni, Co or Mo.

13., it is characterized in that the inorganic or organic compound of described Fe, Ni, Co or Mo magnesium-yttrium-transition metal comprises: nine nitric hydrate iron Fe (NO by the preparation method of the compound field emission source of the described linear nano carbon tube of claim 12 ₃) ₃9H ₂O, Nickelous nitrate hexahydrate Ni (NO ₃) ₂6H ₂O, cabaltous nitrate hexahydrate Co (NO ₃) ₂6H ₂O; Iron(III) chloride hexahydrate FeCl ₃6H ₂O, six hydration Nickel Chloride NiCl ₂6H ₂O; The ferrous C of two oxalic acid hydrates ₂FeO ₄2H ₂O, two oxalic acid hydrate nickel C ₂NiO ₄2H ₂O, Diaquaoxalato cobalt C ₂CoO ₄2H ₂O; Four ferric sulfate hydrate Fe ₂(SO ₄) ₃4H ₂O, four molybdic acid hydrate ammonia (NH ₄) ₆Mo ₇O ₂₄4H ₂O and ferritin.