CN213966465U

CN213966465U - Vacuum reactor for preparing graphene by electrifying carbon powder

Info

Publication number: CN213966465U
Application number: CN202022726359.0U
Authority: CN
Inventors: 吕海港; 张全福
Original assignee: Beijing Saiyintuopu Technology Co ltd
Current assignee: Lv Haigang; Taiyuan Saiyin New Materials Technology Co Ltd
Priority date: 2020-11-23
Filing date: 2020-11-23
Publication date: 2021-08-17
Anticipated expiration: 2030-11-23

Abstract

When the graphite alkene is prepared in the carbon powder circular telegram, in order to improve evacuation efficiency and the equipment automation of being convenient for, the utility model provides a carbon powder circular telegram preparation graphite alkene's vacuum reactor, it comprises vacuum chamber, the vacuum intracavity reaction tube of taking upper cover and lower cover and two electrodes from upper and lower cover insertion reaction tube. The reactor greatly reduces the volume of the vacuum cavity and improves the vacuum pumping efficiency; meanwhile, the feeding and discharging from the outside of the vacuum cavity are realized, and the automation of the equipment is convenient to realize.

Description

Vacuum reactor for preparing graphene by electrifying carbon powder

Technical Field

The utility model belongs to nano-material preparation field, concretely relates to vacuum reactor of graphite alkene is prepared in carbon dust circular telegram.

Background

Graphene is a two-dimensional nano material composed of single-layer honeycomb-shaped carbon atoms, is the thinnest, lightest, strongest and hardest material, has excellent electric conduction and heat conduction performance, and is called as the king of materials. The current large-scale production of graphene is primarily a graphite redox process. In view of the problems of complex process technology, waste liquid treatment and the like, the production cost of the graphene is very high, the price of the graphene powder in the market is high, and the large-scale application of the graphene is limited.

WO2020/051000 (Flash Joule Heating Synthesis Method and Compositions theory) discloses a Method for preparing graphene by electric power through a Joule Heating Flash evaporation Method, wherein carbon powder such as carbon black, coke or anthracite is put in a quartz tube, large current is applied for less than 1 second, the temperature is as high as about 3000 ℃, and the carbon powder is instantly changed into graphene. For the estimation of the power cost, only 2 degrees of electricity are needed for producing 1 kg of graphene, and the power cost is as low as 1 yuan. As the temperature of the reactor rises by 10 times within 1 second, the gas in the tube also expands by 10 times rapidly, carbon powder is ejected out of the reactor along with the gas, and the reaction can not be carried out normally. Therefore, the electric flash evaporation method needs to place the quartz tube in a vacuum environment, and avoids the ejection of carbon powder by reducing the gas in the quartz tube.

However, when the whole reaction device is placed in a vacuum environment, the volume of the vacuum cavity is quite large, and the vacuumizing time is long and the efficiency is low. In addition, the reaction device is arranged in the vacuum chamber, so that the feeding and discharging of the quartz tube are very complicated, and the automation of the machine is not facilitated. Therefore, a small vacuum reactor which is convenient for feeding and discharging needs to be designed to meet the requirement of equipment automation.

Disclosure of Invention

The utility model aims at providing a vacuum reactor for preparing graphene by electrifying carbon powder for reducing the size of a vacuum cavity and facilitating feeding and discharging when preparing graphene by electric flash evaporation.

In order to achieve the above object, the utility model adopts the following technical scheme:

a vacuum reactor for preparing graphene by electrifying carbon powder is a reactor which consists of a vacuum cavity with an upper cover and a lower cover, a reaction tube positioned between the upper cover and the lower cover and two electrodes respectively inserted into the reaction tube through the upper cover and the lower cover.

Furthermore, holes are formed in the upper cover and the lower cover of the vacuum cavity and are communicated with the reaction tube.

Further, the reaction tube is made of quartz, alumina ceramic, magnesia ceramic, boron nitride ceramic, Polytetrafluoroethylene (PTFE), polyparaphenylene (PPL), Polybenzimidazole (PBI), Polyetheretherketone (PEEK), Polyimide (PI), or Polyamideimide (PAI).

Furthermore, the tube wall of the reaction tube is provided with a vent hole, and the vacuum cavity and the inner cavity of the reaction tube are communicated at the upper electrode and the lower electrode.

Further, the electrode is copper, tungsten copper alloy, iron, stainless steel, or graphite.

Further, the electrode is provided with 1-5 sealing rings at the position of passing through the upper cover and the lower cover of the vacuum cavity.

The beneficial effects of the utility model reside in that: (1) the utility model discloses a reaction tube has only been placed to vacuum reactor's vacuum cavity, and the volume can dwindle greatly, and the very easy evacuation greatly improves the efficiency of evacuation. (2) The utility model discloses a vacuum reactor's reaction tube leads directly outside the vacuum cavity, can follow outside direct feeding and ejection of compact to the outside, and the equipment of being convenient for is automatic.

Drawings

Fig. 1 is a diagram of a vacuum reactor apparatus for preparing graphene by an electric flash evaporation method according to the present invention.

Fig. 2 is a scanning electron microscope image of the graphene preparation of the present invention.

Fig. 3 is a raman spectrum of the graphene prepared by the present invention.

Detailed Description

The invention is further described with reference to the following figures and examples.

The experimental methods described in the following examples are all conventional methods unless otherwise specified; the starting materials and materials used, if not specifically required, are commercially available. The power supply used was a 100 kilowatt dc power supply (maximum voltage 200V and maximum current 500A).

Example 1

As shown in fig. 1, the vacuum reactor for preparing graphene by electrifying carbon powder in this embodiment includes an insulating vacuum chamber, a quartz tube as a reaction tube, and two copper electrodes. The vacuum cavity is provided with an upper cover 1, a lower cover 2 and a cavity wall 3, and the upper cover is provided with a small vacuumizing hole 4. A quartz reaction tube 5 with the inner diameter of 8 mm is arranged in the vacuum cavity, and the upper part and the lower part of the reaction tube are respectively provided with a small hole 6 which is communicated with the vacuum cavity and the inner cavity of the reaction tube. Carbon powder 7 is placed in the middle of the reaction tube, and the upper and lower surfaces of the carbon powder are compressed by

copper electrodes

8 and 9 with the diameter of 8 mm. In order to ensure the sealing of the vacuum chamber, two sealing rings 10 are used for sealing the electrode and the upper cover and the lower cover of the vacuum chamber, so as to ensure that air leakage cannot occur.

The use method of the vacuum reactor comprises the following steps: the lower electrode 9 was inserted below the reaction tube, 0.1 g of conductive carbon black was poured from above the reactor, and the upper electrode 8 was inserted from above and pressed, and the resistance was measured to be about 1 ohm. Then, a vacuum was drawn from the vacuum port 4 of the vacuum chamber to 0.1 atmosphere. A discharging circuit is connected, a power supply is switched on, the voltage is selected to be 200V, discharging is carried out for 200 milliseconds, and strong light is emitted from the quartz tube. Cutting off power supply, introducing gas into the vacuum cavity, withdrawing the lower electrode, pushing the reacted carbon powder out from the lower opening by the upper electrode, and grinding to obtain black powder. Scanning electron microscopy of these black powders (fig. 2) revealed that a lamellar structure had been produced. The black powders were examined by laser raman spectroscopy to obtain a raman spectrum (fig. 3), in which the G peak indicates the vibration of the graphite sheet, the D peak indicates the size and defect of the graphene sheet, and the 2D peak indicates the number of layers of the graphene. The black powder can be analyzed from a Raman spectrum, and is a graphene nano material with less than 5 layers.

Therefore, the vacuum reactor is not only small, but also can be externally fed and discharged, the operation is very convenient, and the automation of equipment is easy to realize.

Example 2

Using the vacuum reactor of example 1, reaction tubes were fabricated using alumina ceramic, magnesia ceramic, boron nitride ceramic, Polytetrafluoroethylene (PTFE), polyparaphenylene (PPL), Polybenzimidazole (PBI), Polyetheretherketone (PEEK), Polyimide (PI), or Polyamideimide (PAI), respectively, and the inner diameter and wall thickness thereof were the same as those of the quartz tube of example 1, and 0.1 g of conductive carbon black was charged into each of the fabricated reaction tubes to perform an electric flash evaporation reaction. The obtained black powder is tested to obtain a scanning electron micrograph and a Raman spectrogram, the two drawings are basically the same as the embodiment 1, and the prepared graphene material with less than 5 layers is shown.

Therefore, alumina ceramics, magnesia ceramics, boron nitride ceramics, Polytetrafluoroethylene (PTFE), polyparaphenylene (PPL), Polybenzimidazole (PBI), Polyetheretherketone (PEEK), Polyimide (PI), or Polyamideimide (PAI) can be used as materials for reaction tubes for preparing graphene by electric flash evaporation.

Example 3

In example 1, 5 types of vacuum reactors for electric flash preparation were fabricated by attaching 1, 2, 3, 4, and 5 seal rings to the contact portions between the electrodes and the upper and lower covers, respectively. 0.1 g of conductive carbon black was placed in each case. When the reactor is vacuumized, the vacuum degree of the 5 reactors can reach 0.1 atmospheric pressure normally, and the scanning electron microscope image and the Raman spectrum image of the black powder obtained by discharging are the same as or similar to those of the example 1. Therefore, the sealing methods can realize the preparation of graphene by electric flash evaporation and generate the graphene.

Example 4

The copper electrode in example 1 was changed to tungsten, tungsten-copper alloy, iron, stainless steel, or graphite, and 5 vacuum reactors for preparing graphene by electric flash evaporation were respectively fabricated. 0.1 g of conductive carbon black is put into the reactor each time, and the graphene is prepared by electrifying. The scanning electron micrograph and the raman spectrum of the obtained black powder were identical to those of example 1.

Therefore, the upper and lower electrodes may be made of copper, tungsten-copper alloy, iron, stainless steel, or graphite.

The above is only the embodiment of the present invention, not limiting the scope of the present invention, all of which utilize the equivalent structure or equivalent flow transformation made by the content of the present invention, or directly or indirectly applied to other related technical fields, and all included in the same way in the protection scope of the present invention.

Claims

1. A vacuum reactor for preparing graphene by electrifying carbon powder is characterized in that: it is a reactor which is composed of a vacuum cavity with an upper cover and a lower cover, a reaction tube positioned between the upper cover and the lower cover and two electrodes respectively inserted into the reaction tube through the upper cover and the lower cover.

2. The vacuum reactor for preparing graphene by electrifying carbon powder as claimed in claim 1, wherein: the upper cover and the lower cover of the vacuum cavity are provided with holes which are communicated with the reaction tube.

3. The vacuum reactor for preparing graphene by electrifying carbon powder as claimed in claim 1, wherein: the reaction tube is made of quartz, alumina ceramic, magnesia ceramic, boron nitride ceramic, Polytetrafluoroethylene (PTFE), polyparaphenylene (PPL), Polybenzimidazole (PBI), Polyetheretherketone (PEEK), Polyimide (PI) or polyamide-imide (PAI).

4. The vacuum reactor for preparing graphene by electrifying carbon powder as claimed in claim 1, wherein: the tube wall of the reaction tube is provided with a vent hole, and the upper electrode and the lower electrode are communicated with the vacuum cavity and the inner cavity of the reaction tube.

5. The vacuum reactor for preparing graphene by electrifying carbon powder as claimed in claim 1, wherein: the electrode is copper, tungsten copper alloy, iron, stainless steel or graphite.

6. The vacuum reactor for preparing graphene by electrifying carbon powder as claimed in claim 1, wherein: the electrode is provided with 1-5 sealing rings at the position of penetrating through the upper cover and the lower cover of the vacuum cavity.