CN1528663A - Method for preparing onion-like fullerene by CVD - Google Patents

Abstract

The invention discloses an onion Fuller-alkene CVD preparing method, horizontally placing the quartz tube in the high-temperature diffusing furnace, pushing the quartz boat holding catalyst and Y-zeolite carrier in the center of the quartz tube, when the high-temperature furnace is heated to 500-1300deg.C, feeding the mixed gas of hydrocarbon and Ar inertia carrier gas in the proportion of 1 to 5-10, and making decomposition, diffusion and precipitation of the hydrocarbon on the activated catalyst surface so as to complete the growth of the onion Fuller-alkene. It selects Y-zeolite carrier as Co catalyst carrier, not only synthesizing macro onion Fuller-alkene but having no unformed carbon black.

Description

The CVD preparation method of onion-like fullerene

Technical field

The present invention relates to a kind of preparation method of soccerballene, that concrete is a kind of CVD preparation method of onion-like fullerene.

Background technology

Onion-like fullerene is the same with carbon nanotube also to be a member in the soccerballene family, because its particular structure and performance are expected as photoelectron material, superconducting material, catalyzer and pharmaceutical industries etc.Effectively the preparation method is further investigation onion-like fullerene character and key in application.At present, the preparation method of soccerballene mainly is arc discharge method and laser evaporation method etc.Laser method is to evaporate graphite with pulsed laser technique, and the quick cooling of carbon vapor has caused the formation of soccerballene, but can't collect the sample of constant with this method.Arc process is the method for traditional production soccerballene, its ultimate principle is: when strong current makes between two carbon dioxide process carbon electrodes when forming electric arc, arc-over makes the carbon-point gasification form plasma body, and under the inert atmosphere, little carbon molecule forms stable fullerene molecule through repeatedly colliding.But arc discharge method equipment complexity, its device relates to strong current generator, arc chamber, vacuum system and water-cooling system.Therefore the factor that influences the soccerballene productive rate is too many, and except catalyzer and gaseous species, reaction also is subjected to the influence as all multiparameters such as electrode materials, geometrical shape, interpole gap, pressure and size of current; And in the product that makes, the coexistence of the carbon product of onion-like fullerene and carbon nanotube and unformed shape, the separation and purification difficulty, yield is lower.

Summary of the invention

The problem that in aforesaid method, exists, we attempt to provide a kind of CVD preparation method of onion-like fullerene, purpose is to solve the laser evaporation method to be difficult to collect the constant sample, and it is too many that arc discharge method prepares the factor that the soccerballene method relates to, complex process and unmanageable problem.

The chemical vapor deposition (CVD) method that is used for the onion-like fullerene preparation is: silica tube is lain in a horizontal plane in high temperature dispersing furnace, the quartz boat that is placed with catalyzer and Y-type Zeolite support is pushed silica tube central authorities, after treating that resistance furnace is heated to 500 ℃～1300 ℃ temperature, the feeding ratio is 1: 5～1: 10 the hydrocarbon polymer and the gas mixture of Ar inert carrier gas, in the decomposition of activatory catalyst surface generation hydrocarbon polymer, spread and separate out, finish the growth of onion-like fullerene.

Wherein: described catalyzer is the catalyzer that is decomposed to form by cobaltous acetate, nickelous acetate; Described hydrocarbon polymer is C ₂H ₂, C ₂H ₄And C ₃H ₆

The CVD preparation method of onion-like fullerene follows these steps to carry out successively:

The first step, use the immersion process for preparing catalyst sample: the configuration cobaltous acetate aqueous solution adds Y-type zeolite then and evenly stirs after 24 hours 60 ℃ of oven dry in this solution;

Second step, the sample segment after the oven dry is put into inherent 450 ℃ of high temperature dispersing furnace, roasting is 4.5 hours in atmosphere.Its objective is that in order further to remove residual moisture content and to decompose cobaltous acetate be cobalt oxide, make that cobalt contents is 2.5% in the catalyst prepared sample;

The 3rd the step, sealed silica envelope leads to argon gas, be warming up to 700 ℃ after, feeding ratio again is 1: 8 the acetylene and the gas mixture of argon gas, reacts 15～30 minutes;

The 4th step, cut off source of the gas, under argon atmospher, be cooled to room temperature.

Advantage of the present invention is that this method is compared with arc discharge method with prior art laser evaporation method with positively effect, not only can collect the constant sample, and the influential parameter of generation onion-like fullerene only is carbon containing source of the gas, catalyzer, support of the catalyst kind, furnace temperature and gas flow ratio.Before reaction, just can determine that a need pilot-gas throughput ratio just can realize the artificial control to whole process in the reaction for preceding four.We select for use Y-shaped molecular sieve as the Co support of the catalyst, the onion-like fullerene that has not only synthesized the magnanimity level, but also do not contain the carbon black of unformed shape in the onion-like fullerene product of finding to generate with this kind CVD method, not only improved its productive rate but also simplified purification procedures, and the research that forms aspects such as mechanism, performance and application for it provides condition.This method prepares onion-like fullerene, and not only low than arc discharge method cost, process is easy to control, and the product that makes separates purification easily.Fig. 2 is the onion-like fullerene after purifying, and purity can reach 98%.

Description of drawings

Fig. 1 is the TEM onion-like fullerene figure under 100,000 times of the present invention's the cobalt catalyst effect

Fig. 2 is the TEM onion-like fullerene figure under 500,000 times of the present invention's the cobalt catalyst effect

Embodiment

Silica tube is lain in a horizontal plane in the resistance furnace, the quartz boat that is placed with catalyzer and carrier is pushed silica tube central authorities, after treating that high temperature dispersing furnace is heated to 500 ℃～1300 ℃ temperature, the feeding ratio is 1: 5～1: 10 the hydrocarbon polymer and the gas mixture of Ar inert carrier gas, in the decomposition of activatory catalyst surface generation hydrocarbon polymer, spread and separate out, finish the growth of onion-like fullerene.

Embodiment 1

The method steps of onion-like fullerene preparation is as follows:

1. be mixed with solution with 1 gram cobaltous acetate and 60ml distilled water.

2. in solution, add 10 gram Y-type zeolites, evenly stirred 24 hours, then 60 ℃ of oven dry.

3. get the gram of 1.5 in the above-mentioned oven dry thing and put into resistance heading furnace, at 450 ℃, roasting is 4.5 hours in the atmosphere.

4. the logical argon gas of sealed silica envelope, be warming up to 700 ℃ after, feeding ratio again is 1: 8 the 25ml/min acetylene and the gas mixture of 300ml/min argon gas, reacts 25 minutes.

5. cut off source of the gas then, under the 100ml/min argon atmospher, be cooled to room temperature.

Embodiment 2

Silica tube is placed in the resistance furnace, again the quartz boat that is placed with catalyzer and carrier is pushed silica tube central authorities, after treating the high temperature dispersing furnace heat temperature raising, feed hydrocarbon polymer and carrier gas, in the decomposition of activatory catalyst surface generation hydrocarbon polymer, spread and separate out, finish the growth of onion-like fullerene.1. be mixed with solution with 1 gram nickelous acetate and 60ml distilled water.

2. in solution, add 10 gram Y-type zeolites, evenly stirred 24 hours, then 60 ℃ of oven dry.

3. get the gram of 1.5 in the above-mentioned oven dry thing and put into resistance heading furnace, at 450 ℃, roasting is 4.5 hours in the atmosphere.

4. the logical argon gas of sealed silica envelope, be warming up to 700 ℃ after, feeding ratio again is 1: 8 the 25ml/min acetylene and the gas mixture of 300ml/min argon gas, reacts 25 minutes.

5. cut off source of the gas then, under the 100ml/min argon atmospher, be cooled to room temperature.

Embodiment 3

1. be mixed with solution with 1 gram cobaltous acetate and 60ml distilled water.

2. in solution, add 10 gram Y-type zeolites, evenly stirred 24 hours, then 60 ℃ of oven dry.

3. get the gram of 1.5 in the above-mentioned oven dry thing and put into resistance heading furnace, at 450 ℃, roasting is 4.5 hours in the atmosphere.

4. the logical argon gas of sealed silica envelope, be warming up to 700 ℃ after, feeding ratio again is 1: 8 the 25ml/min ethene and the gas mixture of 300ml/min argon gas, reacts 25 minutes.

5. cut off source of the gas then, under the 100ml argon atmospher, be cooled to room temperature.

Embodiment 4

1. be mixed with solution with 1 gram nickelous acetate and 60ml distilled water.

2. in solution, add 10 gram Y-type zeolites, evenly stirred 24 hours, then 60 ℃ of oven dry.

3. get the gram of 1.5 in the above-mentioned oven dry thing and put into resistance heading furnace, at 450 ℃, roasting is 4.5 hours in the atmosphere.

4. the logical argon gas of sealed silica envelope, be warming up to 700 ℃ after, feeding ratio again is 1: 8 the 25ml/min ethene and the gas mixture of 300ml/min argon gas, reacts 25 minutes.

5. cut off source of the gas then, under the 100ml argon atmospher, be cooled to room temperature.

Embodiment 5

1. be mixed with solution with 1 gram cobaltous acetate and 60ml distilled water.

2. in solution, add 10 gram Y-type zeolites, evenly stirred 24 hours, then 60 ℃ of oven dry.

3. get the gram of 1.5 in the above-mentioned oven dry thing and put into resistance heading furnace, at 450 ℃, roasting is 4.5 hours in the atmosphere.

4. the logical argon gas of sealed silica envelope, be warming up to 700 ℃ after, feeding ratio again is 1: 8 the 25ml/min propane and the gas mixture of 300ml/min argon gas, reacts 25 minutes.

5. cut off source of the gas then, under the 100ml argon atmospher, be cooled to room temperature.

Embodiment 6

1. be mixed with solution with 1 gram nickelous acetate and 60ml distilled water.

2. in solution, add 10 gram Y-type zeolites, evenly stirred 24 hours, then 60 ℃ of oven dry.

3. get the gram of 1.5 in the above-mentioned oven dry thing and put into resistance heading furnace, at 450 ℃, roasting is 4.5 hours in the atmosphere.

4. the logical argon gas of sealed silica envelope, be warming up to 700 ℃ after, feeding ratio again is 1: 8 the 25ml/min propane and the gas mixture of 300ml/min argon gas, reacts 25 minutes.

5. cut off source of the gas then, under the 100ml argon atmospher, be cooled to room temperature.

Claims (4)

1. the CVD preparation method of onion-like fullerene: it is characterized in that this method is that silica tube is lain in a horizontal plane in the high temperature dispersing furnace, the quartz boat that is placed with catalyzer and Y-type Zeolite support is pushed silica tube central authorities, after treating that resistance furnace is heated to 500 ℃～1300 ℃ temperature, the feeding ratio is 1: 5～1: 10 the hydrocarbon polymer and the gas mixture of Ar inert carrier gas, in the decomposition of activatory catalyst surface generation hydrocarbon polymer, spread and separate out, finish the growth of onion-like fullerene.

2. the CVD preparation method of onion-like fullerene according to claim 1 is characterized in that this catalyzer is the catalyzer that is decomposed to form by cobaltous acetate, nickelous acetate.

3. the CVD preparation method of onion-like fullerene according to claim 1 is characterized in that hydrocarbon polymer is C ₂H ₂, C ₂H ₄And C ₃H ₆

4. the CVD preparation method of onion-like fullerene according to claim 1 is characterized in that this method follows these steps to carry out successively:

The first step, use the immersion process for preparing catalyst sample: the configuration cobaltous acetate aqueous solution adds Y-type zeolite then and evenly stirs after 24 hours 60 ℃ of oven dry in this solution;

Second step, the sample segment after the oven dry is put into inherent 450 ℃ of high temperature dispersing furnace, roasting is 4.5 hours in atmosphere.Its objective is that in order further to remove residual moisture content and to decompose cobaltous acetate be cobalt oxide, make that cobalt contents is 2.5% in the catalyst prepared sample;

The 3rd the step, sealed silica envelope leads to argon gas, be warming up to 700 ℃ after, feeding ratio again is 1: 8 the acetylene and the gas mixture of argon gas, reacts 15～30 minutes;

The 4th step, cut off source of the gas, under argon atmospher, be cooled to room temperature.

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