CN110255542A - A kind of grapheme tube and preparation method thereof - Google Patents

Abstract

A graphene tube of the present invention and a preparation method thereof are prepared from the following components in the graphene tube by mass ratio, millimeter-scale balls: powder material=(3-6): 1, and powder material is in a mass ratio of (490 ‑2000):1 micron-sized metal powder and graphene. The preparation method is as follows: prepare materials as needed, put graphene, micron-scale powder and millimeter-scale balls into a ball mill tank according to the proportion to mix, add a corresponding amount of solvent to the ball ink tank, vacuum the ball mill tank, control the ball milling time and The rotating speed is ball-milled, and after completion, the powder is dried to obtain a graphene tube. In the invention, the problem of graphene agglomeration is effectively improved by dispersing an anhydrous ethanol solution, the synergistic effect of large and small balls is matched with a semi-dry ball milling environment, and graphene can form a graphene tube, the conditions are controllable, the operation is simple, and the cost is low. Under the selected parameters, the graphene tube can be stably made, and the prepared graphene tube has good performance.

Description

A kind of graphene tube and preparation method thereof

Technical field:

The invention belongs to the technical field of nanomaterials, and in particular relates to a graphene tube and a preparation method thereof.

Background technique:

Graphene is a hexagonal honeycomb-like planar structure composed of densely arranged carbon atoms, and is a two-dimensional carbon nanomaterial with a thickness of only one carbon atom. A graphene tube is a nanoscale structure formed by rolling graphene. It can be used in composite materials, energy storage, microprobes, micromechanical components, microelectronics, microcircuits, military aerospace, armor protection and sensors. In recent years, the research momentum of nanomaterials has not diminished, graphene has attracted much attention, and graphene tubes have a bright future.

In the existing published patents, chemical methods are mainly used, and the chemical methods are affected by various factors such as the concentration ratio of chemical reagents, and the stability is poor. The method of the invention belongs to a physical method, and the graphene tube can be stably obtained under optimized parameters.

Invention content:

The object of the present invention is to overcome the deficiencies in the above-mentioned prior art, and to provide a graphene tube and a preparation method thereof, wherein the graphene is made into a graphene tube based on semi-dry ball milling and the synergistic effect of large and small balls.

To achieve the above object, the present invention adopts the following technical solutions:

A graphene tube is prepared from the following components in mass proportions. According to the mass ratio, millimeter-level balls: powder material=(3-6): 1, and the powder material is micron-level metal powder and graphene, By mass ratio, micron powder: graphene=(490-2000):1.

The diameter of the millimeter-grade ball is 2-5mm, and the material of the millimeter-grade ball is stainless steel ball, zirconia ball or agate ball.

The micron-level metal powder is one of cast aluminum powder, titanium powder or copper powder, and the particle size of the micron-level metal powder is 60-120 mesh.

The diameter of the graphene tube is 30-50nm.

The electrical conductivity of the graphene tube is 300-1400 S/cm, and the carbon-oxygen ratio is (1-12):1.

A preparation method of a graphene tube, comprising the following steps:

Step 1, preparation:

(1) prepare micron-level metal powder, and the particle size of the micron-level metal powder is 60-120 mesh;

(2) prepare solvent, wherein, described solvent is dehydrated alcohol or acetone;

(3) Graphene preparation:

Graphene is prepared by oxidation method, expansion method, CVD method or mechanical exfoliation method;

(4) Prepare millimeter-level balls, and the diameter of the millimeter-level balls is 2-5mm;

Step 2, graphene tube preparation:

(1) According to mass ratio, millimeter-scale ball: powder = (3-6): 1, the powder is micron-scale metal powder and graphene, according to mass ratio, micron-scale powder: graphene = (500- 2000): 1, put graphene, micron-scale powder and millimeter-scale ball into a ball mill tank to form a mixture, and add a solvent to the spherical ink tank, the ratio of the mixture to the solvent is 12: (1～2), and the unit is g:ml, after the ball mill jar is evacuated, put it into the ball mill, ball mill for 6h-12h, and the ball mill rotation speed is 250-500r/min;

(2) After the ball milling is stopped, the powder is dried to obtain a graphene tube.

In the step 1 (1), the metal powder is one of cast aluminum powder, titanium powder or copper powder.

In the step 1 (3), the prepared graphene is few-layer graphene.

In the described step 1 (3), the specific process of preparing graphene by oxidation method is:

Mix well with 23ml of concentrated sulfuric acid, 4g of potassium permanganate and 1g of graphite, react at 40°C for 30min, then add deionized water to dilute, add 5ml of 30% hydrogen peroxide to remove potassium permanganate, use 250ml of 10% mass concentration Wash with dilute hydrochloric acid, and finally blow dry at no higher than 30 degrees Celsius to obtain graphene.

In the described step 1 (3), the specific preparation process of the graphene prepared by the expansion method is:

The intercalated expandable graphite raw material is taken and expanded in a muffle furnace at 600-800° C. for 1-4 minutes to obtain graphene.

In the described step 1 (3), the expanded graphene raw material is the 1395 model intercalation expandable graphite raw material purchased in the United States.

In the step 1 (4), the material of the millimeter-scale ball is one of stainless steel ball, zirconia ball or agate ball.

In the described step 2 (1), the graphene is added with a solvent before use, and ultrasonically oscillated for 1h-2h, in order to make the multi-layer graphene form few-layer graphene in the solvent, and the solvent is anhydrous ethanol.

In the step 2(1), the millimeter-scale ball is added with a solvent before use, and ultrasonically oscillated for 20min-40min, and the solvent is anhydrous ethanol.

In the step 2(1), the spherical ink tank is evacuated to a degree of vacuum of 4.0×10 ⁻² Pa.

In the described step 2(1), during the ball milling, every 30min stops for 5-15min.

In the preparation process of the graphene tube of the present invention, the micron-scale powder is used as the main body, and the millimeter-scale ball is added as an auxiliary at the same time, and the graphene tube can be prepared by using the synergistic effect of the micron-scale powder and the millimeter-scale ball to grind graphene. At the same time, the selection of the amount of the ball milling solvent in the ball milling process is also a key condition for graphene to be made into graphene tubes.

Beneficial effects of the present invention:

The invention uses anhydrous ethanol solution to disperse graphene to effectively improve the graphene agglomeration problem, the synergistic effect of large and small balls and the semi-dry method of ball milling environmental graphene can form graphene tubes, the conditions are controllable, the operation is simple, and the cost is relatively low. low, graphene tubes can be stably fabricated under selected parameters.

Description of drawings:

Fig. 1 is the preparation method steps flow chart of the graphene tube of embodiment 1;

Fig. 2 is the SEM image under 500 times of scanning electron microscopes of the graphene tube prepared in Example 3;

Fig. 3 is the SEM image under 2K times scanning electron microscope of the graphene tube prepared in Example 3;

Fig. 4 is the SEM image under 10K times scanning electron microscope of the graphene tube prepared in Example 3;

FIG. 5 is a SEM image of the graphene tube prepared in Example 3 under a scanning electron microscope at a magnification of 20K.

6 is a 40000 times TEM image of the graphene tube obtained in Example 3;

Fig. 7 is the 5K times SEM image of the sheet graphene obtained in Comparative Example 2;

Fig. 8 is the 20K times SEM image of the sheet graphene obtained in Comparative Example 2;

9 is a 50K magnification SEM image of the sheet graphene obtained in Comparative Example 2.

Detailed ways:

The present invention will be further described in detail below in conjunction with the examples.

In the following examples:

The ultrasonic equipment model used is KQ3200B, and the ultrasonic frequency is 40KHZ;

The ball mill adopts high-energy planetary ball mill;

The specific process of preparing graphene by oxidation method is as follows:

Mix well with 23ml of concentrated sulfuric acid, 4g of potassium permanganate and 1g of graphite, react at 40°C for 30min, then add deionized water to dilute, add 5ml of 30% hydrogen peroxide to remove potassium permanganate, use 250ml of 10% mass concentration Wash with dilute hydrochloric acid, and finally blow dry at no higher than 30 degrees Celsius to obtain graphene.

The specific preparation process of graphene prepared by expansion method is as follows:

Take the 1395 type intercalated expandable graphite raw material purchased in the United States, and expand it in a muffle furnace at 600-800 ° C for 1 to 4 minutes to obtain graphene;

The graphene prepared by oxidation method is referred to as graphene oxide, and the graphene prepared by expansion method is referred to as expanded graphene; the resulting form of graphene oxide and expanded graphene are both few-layer graphene;

Before adding the millimeter ball into the ball mill, add absolute ethanol for ultrasonic vibration for 20 minutes, rinse and dry, and then add to the ball mill;

Before graphene is used, according to the ratio, graphene: anhydrous ethanol = 1:300, unit g:ml, add anhydrous ethanol for ultrasonic vibration for 1h, so that the multi-layer graphene is oscillated into few-layer graphene, and then add ball milling Can;

The millimeter balls used in Examples 1 to 3 and Comparative Examples 1 to 3 are stainless steel balls with a diameter of 3 mm;

The millimeter-level balls used in Examples 4 to 5 are zirconia balls with a diameter of 2 mm;

The millimeter-scale balls used in Example 6 were agate balls with a diameter of 2 mm.

Example 1

A method for preparing a graphene tube, the flow chart of the steps is shown in Figure 1, according to the mass ratio, millimeter-scale balls: (cast aluminum powder ZL114A: + expanded graphene) = 5:1, cast aluminum powder ZL114A: expanded graphene = 1999:1, put graphene, cast aluminum powder ZL114A and millimeter-scale balls into the ball mill tank to form a mixture, and add absolute ethanol to the spherical ink tank, the ratio of the mixture to absolute ethanol is 600:60, unit as g:ml. The ball mill jar was evacuated, the vacuum degree was 4.0×10 ^-2 Pa, the ball mill jar was put into the ball mill, the ball milling time was 8h (stop for 15min every 30min), the ball milling speed was adjusted to 250r/min, and the ball mill was dried to obtain a graphene tube , the diameter is 42-45nm, the conductivity is 1000-1200S/cm, and the carbon-oxygen ratio is 10:1.

Example 2

A method for preparing a graphene tube, the flow chart of the steps is shown in Figure 1, according to the mass ratio, millimeter-scale ball: (titanium alloy TC4 powder+expanded graphene)=4:1, titanium alloy TC4 powder: expanded graphene= 1999:1, put graphene, titanium alloy TC4 powder and millimeter-scale balls into the ball mill tank to form a mixture, and add absolute ethanol to the spherical ink tank. The ratio of the mixture to absolute ethanol is 600:60, and the unit is g:ml. The ball mill jar was evacuated, the vacuum degree was 4.0×10 ^-2 Pa, the ball mill jar was put into the ball mill, the ball milling time was 8h (stop for 15min every 30min), the ball milling speed was adjusted to 250r/min, and the ball mill was dried to obtain a graphene tube , the diameter is 46-48nm, the conductivity is 1000-1200S/cm, and the carbon-oxygen ratio is 10:1.

Example 3

A method for preparing a graphene tube, the flow chart of the steps is shown in Figure 1, according to the mass ratio, millimeter-scale balls: (cast aluminum powder ZL114A+expanded graphene)=5:1, cast aluminum powder ZL114A: expanded graphene=499 : 1, put graphene, cast aluminum powder ZL114A and millimeter-grade balls into the ball mill tank to form a mixture, and add absolute ethanol to the spherical ink tank, the ratio of the mixture to absolute ethanol is 600:60, the unit is g :ml. The ball mill jar was evacuated, the vacuum degree was 4.0×10 ^-2 Pa, the ball mill jar was put into the ball mill, the ball milling time was 8h (stop for 15min every 30min), the ball milling speed was adjusted to 250r/min, and the ball mill was dried to obtain a graphene tube , the diameter is 30-34nm, the conductivity is 1360-1400S/cm, and the carbon-to-oxygen ratio is 12:1. The SEM image of the graphene tube under 500 times scanning electron microscope is shown in Figure 2, the SEM image under 2K times scanning electron microscope is shown in Figure 3, the SEM image under 10K times scanning electron microscope is shown in Figure 4, and the 20K times scanning electron microscope is shown in Figure 4 The SEM image under the SEM image is shown in Figure 5, and the TEM image under the 40000x transmission electron microscope is shown in Figure 6.

Comparative Example 1: The applicant found through research that: Graphene tubes could not be produced by using millimeter-scale balls and graphene ball milling alone, and graphene tubes could not be produced by using micron-scale powders and graphene ball milling alone. The experiment is as follows: put millimeter-scale balls and expanded graphene in the ball mill. Under the same experimental conditions in Example 3, the expanded graphene still presents a lamellar non-tubular shape. Only micron-sized powder and expanded graphene were placed in the ball mill. Under the same experimental conditions in Example 3, the expanded graphene still showed a lamellar non-tubular shape.

Example 4

A method for preparing a graphene tube, the flow chart of the steps is shown in Figure 1, according to the mass ratio, millimeter-scale balls: (cast aluminum powder ZL114A+graphene oxide)=5:1, cast aluminum powder ZL114A: graphene oxide=1999 : 1, put graphene, cast aluminum powder ZL114A and millimeter-grade balls into the ball mill tank to form a mixture, and add absolute ethanol to the spherical ink tank, the ratio of the mixture to absolute ethanol is 600:80, the unit is g :ml. The ball mill jar was evacuated, the vacuum degree was 4.0×10 ^-2 Pa, the ball mill jar was put into the ball mill, the ball milling time was 10h (stop for 15min every 30min), the ball milling speed was adjusted to 250r/min, and the ball mill was dried to obtain a graphene tube , the diameter is 38-40nm, the conductivity is 900-1050S/cm, and the carbon-oxygen ratio is (8-10):1.

Example 5

A preparation method of a graphene tube, the flow chart of the steps is shown in Figure 1, according to the mass ratio, millimeter-scale balls: (cast aluminum powder ZL114A+graphene oxide)=5:1, cast aluminum powder ZL114A: graphene oxide=499 : 1, put graphene, cast aluminum powder ZL114A and millimeter-grade balls into the ball mill tank to form a mixture, and add absolute ethanol to the spherical ink tank, the ratio of the mixture to absolute ethanol is 600:80, the unit is g :ml. The ball mill jar was evacuated, the vacuum degree was 4.0×10 ^-2 Pa, the ball mill jar was put into the ball mill, the ball milling time was 8h (stop for 15min every 30min), the ball milling speed was adjusted to 250r/min, and the ball mill was dried to obtain a graphene tube , the diameter is 39-42nm, the conductivity is 800-1000S/cm, and the carbon-oxygen ratio is (6-9):1.

Example 6

A method for preparing a graphene tube, the flow chart of the steps is shown in Figure 1, according to the mass ratio, millimeter-scale balls: (titanium alloy TC4 powder+graphene oxide)=5:1, titanium alloy TC4 powder: graphene oxide= 1999:1, put graphene, titanium alloy TC4 powder and millimeter-scale balls into the ball mill tank to form a mixture, and add absolute ethanol to the spherical ink tank. The ratio of the mixture to absolute ethanol is 600:80, and the unit is g:ml. The ball mill jar was evacuated, the vacuum degree was 4.0×10 ^-2 Pa, the ball mill jar was put into the ball mill, the ball milling time was 10h (stop for 15min every 30min), the ball milling speed was adjusted to 250r/min, and the ball mill was dried to obtain a graphene tube , the diameter is 40-50nm, the conductivity is 300-600S/cm, and the carbon-oxygen ratio is (1-4):1.

Comparative Example 2

Wet ball milling, by mass ratio, millimeter-scale ball: (cast aluminum powder ZL114A + expanded graphene) = 5:1, cast aluminum powder ZL114A: expanded graphene = 499:1, graphene, cast aluminum powder ZL114A and millimeter-scale The balls are put into the ball mill tank to form a mixture, and absolute ethanol is added to the spherical ink tank. The ratio of the mixture to absolute ethanol is 600:160, and the unit is g:ml. The ball mill jar was evacuated, the vacuum degree was 4.0×10 ^-2 Pa, the ball mill jar was put into the ball mill, the ball milling time was 12h (stop for 15min every 30min), the ball milling speed was adjusted to 250r/min, and the graphene was dried after ball milling. It is still lamellar, the SEM image under 5K magnification scanning electron microscope is shown in Figure 7, the SEM image under 20K magnification scanning electron microscope is shown in Figure 8, and the SEM image under 50K magnification scanning electron microscope is shown in Figure 9.

Comparative Example 3

Dry ball milling, by mass ratio, millimeter ball: (cast aluminum powder ZL114A+) = 5:1, cast aluminum powder ZL114A: expanded graphene = 499:1, put graphene, cast aluminum powder ZL114A and millimeter ball into A mixture is formed in the ball mill jar, the ball mill jar is evacuated, the vacuum degree is 4.0×10 ^-2 Pa, the ball mill jar is put into the ball mill, the ball milling time is 12h (stop for 15min every 30min), the ball mill rotation speed is adjusted to 250r/min, and the ball mill is dried. When dry, graphene agglomerates obviously and forms agglomerates.

Claims (10)

1. a graphene tube, is characterized in that, comprises following mass proportioning components to prepare, by mass ratio, millimeter-level ball: powder material=(3-6): 1, and described powder material is micron level Metal powder and graphene, by mass ratio, micron powder: graphene = (490-2000): 1. 2. Graphene tube according to claim 1, is characterized in that, described millimeter-level ball diameter is 2-5mm, and described millimeter-level ball material is stainless steel ball, zirconia ball or agate ball. 3. graphene tube according to claim 1, is characterized in that, described micron-level metal powder is a kind of in cast aluminum powder, titanium powder or copper powder, and described micron-level metal powder granularity is 60- 120 mesh. 4. The graphene tube according to claim 1, wherein the graphene tube has a diameter of 30-50 nm. 5 . The graphene tube according to claim 1 , wherein the electrical conductivity of the graphene tube is 300-1400 S/cm, and the carbon-to-oxygen ratio is (1-12):1. 6 . 6. the preparation method of the graphene tube of claim 1, is characterized in that, comprises the following steps: Step 1, preparation: (1) prepare micron-level metal powder, and the particle size of the micron-level metal powder is 60-120 mesh; (2) prepare solvent, wherein, described solvent is dehydrated alcohol or acetone; (3) Graphene preparation: Graphene is prepared by oxidation method, expansion method, CVD method or mechanical exfoliation method; (4) Prepare millimeter-level balls, and the diameter of the millimeter-level balls is 2-5mm; Step 2, graphene tube preparation: (1) According to mass ratio, millimeter-scale ball: powder = (3-6): 1, the powder is micron-scale metal powder and graphene, according to mass ratio, micron-scale powder: graphene = (500- 2000): 1, put graphene, micron-scale powder and millimeter-scale ball into a ball mill tank to form a mixture, and add a solvent to the spherical ink tank, the ratio of the mixture to the solvent is 12: (1～2), and the unit is g:ml, after the ball mill jar is evacuated, put it into the ball mill, ball mill for 6h-12h, and the ball mill rotation speed is 250-500r/min; (2) After the ball milling is stopped, the powder is dried to obtain a graphene tube. 7. the preparation method of graphene tube according to claim 6, is characterized in that, in described step 2 (1), graphene adds solvent before use, ultrasonic vibration 1h-2h, and described solvent is no water ethanol. 8. the preparation method of graphene tube according to claim 6, is characterized in that, in described step 2 (1), millimeter ball adds solvent before use, ultrasonic vibration 20min-40min, and described solvent is Anhydrous ethanol. 9 . The method for preparing a graphene tube according to claim 6 , wherein in the step 2 (1), the spherical ink tank is evacuated to a degree of vacuum of 4.0×10 ⁻² Pa. 10 . 10. The method for preparing a graphene tube according to claim 6, wherein in the step 2(1), in the ball milling process, every 30min is stopped for 5-15min.