CN107686108A - The method that dielectric barrier discharge plasma prepares redox graphene - Google Patents
The method that dielectric barrier discharge plasma prepares redox graphene Download PDFInfo
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- CN107686108A CN107686108A CN201710855342.5A CN201710855342A CN107686108A CN 107686108 A CN107686108 A CN 107686108A CN 201710855342 A CN201710855342 A CN 201710855342A CN 107686108 A CN107686108 A CN 107686108A
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- dielectric barrier
- barrier discharge
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- C01B2204/00—Structure or properties of graphene
- C01B2204/02—Single layer graphene
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- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B2204/00—Structure or properties of graphene
- C01B2204/04—Specific amount of layers or specific thickness
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- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B2204/00—Structure or properties of graphene
- C01B2204/20—Graphene characterized by its properties
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- C01P2002/70—Crystal-structural characteristics defined by measured X-ray, neutron or electron diffraction data
- C01P2002/72—Crystal-structural characteristics defined by measured X-ray, neutron or electron diffraction data by d-values or two theta-values, e.g. as X-ray diagram
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2002/00—Crystal-structural characteristics
- C01P2002/80—Crystal-structural characteristics defined by measured data other than those specified in group C01P2002/70
- C01P2002/88—Crystal-structural characteristics defined by measured data other than those specified in group C01P2002/70 by thermal analysis data, e.g. TGA, DTA, DSC
Abstract
The present invention relates to a kind of method that dielectric barrier discharge plasma prepares redox graphene, comprise the following steps：(1) between two electrodes graphene oxide being placed in plasma device；(2) plasma discharge gas is passed through；(3) high voltage is applied on two electrodes, and device produces plasma, and finished product is obtained after handling a period of time.In the present invention, equipment is simple, easy to operate, energy consumption is low, pollution-free, and production efficiency is high, and carbon source conversion ratio reaches more than 90%, 100m of the specific surface area from heat treatment reducing process2/ g or so brings up to 400m2/ more than g, it is a kind of cost novel processing step that is low, easy to spread, being adapted to actual production.
Description
Technical field
The invention belongs to graphene manufacturing process technical field of improvement, more particularly, to a kind of dielectric barrier discharge plasma
The method that body prepares redox graphene.
Background technology
Graphene is with sp by carbon atom2The two-dimension nano materials that hybridized orbit is formed by honeycomb crystal lattice arrangement, have
Good intensity, pliability, electric conductivity, thermal conductivity, optical characteristics, it is considered to be microelectronic component of future generation, organic photoelectric material
The preferred material in the field such as material, high-efficiency energy-storage material, multifunctional composite and biological medicine.
At present, redox graphene method is considered as to prepare the most viable method of graphene, specifically including on a large scale
Learn reducing process, photo-reduction, electrochemical reducing and thermal reduction etc..Be present the defects of respective in above-mentioned each method, such as change
Learn the reducing agent that reducing process uses and high pollution, highly toxic shortcoming be present, and need to subsequently remove, complex operation；Photo catalytic reduction
Method is up to more than 5 hours and need to be difficult to the photochemical catalyst separated reaction time；Electrochemical reducing is in the low dense of 0.1~5mg/mL
Carried out in degree graphene oxide dispersion, treating capacity is low, and graphenic surface tension force is big, easily reunites, is unfavorable for shape
The reduced graphene less into the number of plies；Thermal reduction can be reduced directly to graphene oxide powder under an inert atmosphere,
But higher temperature is needed, operating difficulties, high energy consumption high to equipment requirement.
Retrieved by pertinent literature, there is the report that a small amount of plasma treatment carbon material prepares graphene, for example,
CN102153076A, CN104609408A, CN102781831A using plasma handle graphite, CN101993060A uses etc.
Gas ions handle graphene oxide, but use arc discharge hot plasma, and temperature reaches 4000~5000K high temperature, behaviour
Make difficult, high energy consumption high to equipment requirement；Using plasma polishing technology (CN103484889A) processing hot solution (60~
95 DEG C) in graphite prepare graphene solution, but the graphene of gained is easily agglomerated into particle, is unfavorable for applying, and gained produces
Thing needs the subsequent treatment such as dilution, ultrasound, washing, dry, and the cycle is up to 7 hours；Using microwave plasma
(CN102107870A), inductively coupled plasma (CN104085884A) or glow discharge plasma (CN103818899A)
Processing graphene oxide prepares graphene, and equipment is complicated, treating capacity is few.
In addition, plasma can efficient-decomposition methane, ethane, acetylene, ethanol, the carbon-source gas such as sucrose, can assist
Process for preparing graphenes by chemical vapour deposition, such as：CN105152165A, CN104773725A, CN103570006A,
CN103183334A and CN103708444A, but the method needs for substrate to be placed in 300~1000 DEG C of high-temperature region, 10~1000Pa
Low pressure, device is complicated, and the utilization rate of reactant is low, and yield is few.
The content of the invention
It is an object of the invention to overcome the deficiencies of the prior art and provide easy to operate, energy-saving consumption, environment-friendly and effect
The method that a kind of higher dielectric barrier discharge plasma of rate prepares redox graphene.
The present invention adopts the technical scheme that：
A kind of method that dielectric barrier discharge plasma prepares redox graphene, it is characterised in that：Including following
Step：
(1) between two electrodes graphene oxide being placed in plasma device；
(2) plasma discharge gas is passed through；
(3) high voltage is applied on two electrodes, and device produces plasma, and finished product is obtained after handling a period of time.
Moreover, step (1) the plasma device be point-board-like, board-to-board formula or tubular type dielectric barrier discharge device.
Moreover, step (1) the graphene oxide be single or multiple lift sheet or powdered.
Moreover, step (1) the graphene oxide by Brodie methods, Staudenmaier methods, Hummers methods,
Improved-Hummers methods or Improved methods are made.
Moreover, (2) the plasma discharge gas is one or more of mixing in air, argon gas or nitrogen to step
Thing.
Moreover, the condition of processing procedure is room temperature and normal pressure.
Moreover, (3) the high voltage is 400~1000 volts to step, operating current is 1~10 ampere.
Moreover, step (3) high-voltage discharge time be 3~60 minutes.
The advantages and positive effects of the present invention are：
1. in this method, the dielectric barrier discharge plasma of use prepares redox graphene, directly by raw material one
Footwork is made product, easy to operate, step is simple, compared with the other method of prior art, by processing time from 7 hours with
On shorten within only 1 hour, it is more efficient.
2. being not introduced into other chemical reagent in this method, in processing procedure, be not required to be heated at high temperature, with prior art other
Method is compared, relatively low in resource and energy resource consumption in processing procedure, environment-friendly.
3. in this method, the plasma formed in dielectric barrier discharge device contains a large amount of electronics, these electron attachments
Between every layer of redox graphene, the repulsion of electronics makes its stripping be single or multiple lift graphene, can effectively prevent
Graphene aggregation is grown up again, beneficial to the uniform two-dimensional structure graphene of formation.
4. in the present invention, equipment is simple, easy to operate, energy consumption is low, pollution-free, production efficiency is high, and carbon source conversion ratio reaches
To 90More than %, 100m of the specific surface area from heat treatment reducing process2/ g or so brings up to 400m2/ more than g, be a kind of cost it is low,
Novel processing step that is easy to spread, being adapted to actual production.
Brief description of the drawings
Fig. 1 is the X-ray powder diffraction spectrum of graphene oxide and dielectric barrier discharge redox graphene (DBD-rGO)
Figure；
Fig. 2 is the thermogravimetric curve figure of graphene oxide and dielectric barrier discharge redox graphene (DBD-rGO)；
Fig. 3 is the x-ray photoelectron power spectrum of graphene oxide and dielectric barrier discharge redox graphene (DBD-rGO)
Figure.
Embodiment
With reference to embodiment, the present invention is further described, and following embodiments are illustrative, be not it is limited,
Protection scope of the present invention can not be limited with following embodiments.
A kind of method that dielectric barrier discharge plasma prepares redox graphene, innovation of the invention are：Bag
Include following steps：
(1) between two electrodes graphene oxide being placed in plasma device；Plasma device is point-plate
The dielectric barrier discharge device of formula, board-to-board formula or tubular type, graphene oxide are the sheet or powdered of single or multiple lift, are aoxidized
Graphene is made by Brodie methods, Staudenmaier methods, Hummers methods, Improved-Hummers methods or Improved methods.
(2) plasma discharge gas is passed through；Plasma discharge gas is one kind or several in air, argon gas or nitrogen
The mixture of kind.
(3) high voltage is applied on two electrodes, and device produces plasma, and finished product is obtained after handling a period of time.High electricity
Press as 400~1000 volts, operating current is 1~10 ampere, and the time of high-voltage discharge is 3~60 minutes.
Above-mentioned placement graphene oxide is into the whole processing procedure of finished product, and temperature conditionss are room temperature, pressure condition
For normal pressure.
Above method prior art is completely different, is a kind of gas discharge that dielectric is placed in discharge space, can be
Under normal pressure produce with high electron energy nonequilibrium plasma, high energy electron bombard graphene oxide in the presence of and
Active particle occurs under redox reaction effect with the oxy radical on graphene oxide in electric field, and reduction-oxidation graphite is made
Alkene.
During reduction, the electron adsorption in plasma field is between every layer of redox graphene, electronics
Repulsion make its stripping be single or multiple lift graphene, preparation process can be completed directly at room temperature, without adding other examinations
Agent, it is simple to operate, and also manufacturing cycle is shorter.
Embodiment 1
Multilayer graphene oxide powder prepared by Improved methods is placed in two of board-to-board formula dielectric barrier discharge device
Between electrode, argon gas is passed through under room temperature (20~30 DEG C) as discharge gas, opens high voltage power supply, adjustment work voltage arrives
1000V, operating current to 1.0A, discharge process 3min, products therefrom use XRD, TG, XPS phenetic analysis at room temperature, it was demonstrated that oxygen
Graphite alkene is reduced.Preparation process carbon source conversion ratio 90%, specific surface area 410m2/g.Characterization result is respectively displayed on Fig. 1, and 2
In 3.
Embodiment 2
Multilayer graphene oxide sheet prepared by Staudenmaier methods is placed in the two of board-to-board formula dielectric barrier discharge device
Between individual electrode, nitrogen is passed through under room temperature (20~30 DEG C) as discharge gas, opens high voltage power supply, adjustment work voltage arrives
500V, operating current to 1.0A, discharge process 60min, products therefrom use XRD, TG phenetic analysis at room temperature, it was demonstrated that oxidation
Graphene is reduced.Preparation process carbon source conversion ratio 96%, specific surface area 467m2/g。
Embodiment 3
Single-layer graphene oxide powder prepared by Hummers methods is placed in two of point-board-like dielectric barrier discharge device
Between electrode, air is passed through under room temperature (20~30 DEG C) as discharge gas, opens high voltage power supply, adjustment work voltage arrives
1000V, operating current to 1.0A, discharge process 60min, products therefrom use XRD, TG phenetic analysis at room temperature, it was demonstrated that oxidation
Graphene is reduced.Preparation process carbon source conversion ratio 92%, specific surface area 489m2/g。
Embodiment 4
Single-layer graphene oxide powder prepared by Improved-Hummers methods is placed in tubular type dielectric barrier discharge device
Two electrodes between, be passed through argon gas as discharge gas in room temperature (20~30 DEG C), open high voltage power supply, adjustment work voltage
To 500V, operating current to 10A, discharge process 60min, products therefrom use the phenetic analysis such as XRD, TG at room temperature, it was demonstrated that oxygen
Graphite alkene is reduced.Preparation process carbon source conversion ratio 93%, specific surface area 595m2/g。
Embodiment 5
Single-layer graphene oxide powder prepared by Brodie methods is placed in two electrodes of tubular type dielectric barrier discharge device
Between, air is passed through under room temperature (20~30 DEG C) as discharge gas, opens high voltage power supply, adjustment work voltage to 1000V,
Operating current uses XRD, TG phenetic analysis to 5.0A, at room temperature discharge process 3min, products therefrom, it was demonstrated that graphene oxide quilt
Reduction.Preparation process carbon source conversion ratio 93%, specific surface area 643m2/g。
Embodiment 6
Multilayer graphene oxide sheet prepared by Improved methods is placed in two electrodes of tubular type dielectric barrier discharge device
Between, nitrogen is passed through under room temperature (20~30 DEG C) as discharge gas, opens high voltage power supply, adjustment work voltage to 500V,
Operating current uses XRD, TG phenetic analysis to 10A, at room temperature discharge process 3min, products therefrom, it was demonstrated that graphene oxide quilt
Reduction.Preparation process carbon source conversion ratio 95%, specific surface area 756m2/g。
It is as shown in Figure 1 graphene oxide, heat-treats the X ray of graphene and dielectric barrier discharge redox graphene
Powder diffractogram.Peak near 11 ° belongs to graphene oxide (001) crystal face, and this disappearance shows that graphene oxide is reduced.
X-ray powder diffraction spectrogram with heat-treating graphene oxide contrasts, it can be found that dielectric barrier discharge redox graphene
Peak near 11 ° is wholly absent, and the peak near 23 ° is substantially offset to the right and intensity is relatively low, and this shows through dielectric barrier discharge
After reduction, graphene oxide is reduced to graphene, and the graphene layer spacing that the method obtains is smaller, and reducing degree is higher.
It is illustrated in figure 2 the thermogravimetric of graphene oxide, thermal reduction graphene and dielectric barrier discharge redox graphene
Curve map.The weightlessness of thermal reduction graphene and dielectric barrier discharge redox graphene is significantly lower than graphene oxide, this table
Oxygen-containing functional group on bright redox graphene greatly reduces, and graphene oxide is reduced.
It is illustrated in figure 3 the X ray of graphene oxide, thermal reduction graphene and dielectric barrier discharge redox graphene
Photoelectron spectroscopy figure.For the graphene oxide of reduction, the peak between 286~289eV generally belongs to oxy radical.
In the x-ray photoelectron power spectrum of redox graphene prepared by dielectric barrier discharge method, the disappearance of characteristic peak 286.8eV at and
Characteristic peak at 248.5eV greatly enhances, and shows after dielectric barrier discharge reduces, and the oxygen-containing functional group in graphene oxide is anxious
Reduce sharply less, and reducing degree is more than thermal reduction graphene oxide.
Claims (9)
1. a kind of method that dielectric barrier discharge plasma prepares redox graphene, it is characterised in that：Including following step
Suddenly：
(1) between two electrodes graphene oxide being placed in plasma device；
(2) plasma discharge gas is passed through；
(3) high voltage is applied on two electrodes, and device produces plasma, and finished product is obtained after handling a period of time.
2. the method that dielectric barrier discharge plasma according to claim 1 prepares redox graphene, its feature
It is：Step (1) the plasma device be point-board-like, board-to-board formula or tubular type dielectric barrier discharge device.
3. the method that dielectric barrier discharge plasma according to claim 2 prepares redox graphene, its feature
It is：Step (1) the graphene oxide be single or multiple lift sheet or powdered.
4. the method that the dielectric barrier discharge plasma according to claim 1 or 2 or 3 prepares redox graphene,
It is characterized in that：Step (1) the graphene oxide by Brodie methods, Staudenmaier methods, Hummers methods, Improved-
Hummers methods or Improved methods are made.
5. the dielectric barrier discharge plasma according to claim 1 or 2 or 3 or 4 prepares the side of redox graphene
Method, it is characterised in that：(2) the plasma discharge gas is one or more of mixing in air, argon gas or nitrogen to step
Thing.
6. the method that dielectric barrier discharge plasma according to claim 4 prepares redox graphene, its feature
It is：The condition of processing procedure is room temperature and normal pressure.
7. the method that dielectric barrier discharge plasma according to claim 5 prepares redox graphene, its feature
It is：The condition of processing procedure is room temperature and normal pressure.
8. the dielectric barrier discharge plasma according to claim 1 or 2 or 3 or 6 or 7 prepares redox graphene
Method, it is characterised in that：(3) the high voltage is 400~1000 volts to step, and operating current is 1~10 ampere.
9. the dielectric barrier discharge plasma according to claim 1 or 2 or 3 or 6 or 7 prepares redox graphene
Method, it is characterised in that：Step (3) high-voltage discharge time be 3~60 minutes.
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109179374A (en) * | 2018-08-17 | 2019-01-11 | 山东重山光电材料股份有限公司 | A kind of method of low temperature preparation fluorinated carbon material |
| CN112391094A (en) * | 2020-11-13 | 2021-02-23 | 天长市京发铝业有限公司 | Aluminum-based plate surface wear-resistant coating and preparation method thereof |
| CN113003567A (en) * | 2021-05-06 | 2021-06-22 | 哈尔滨工程大学 | Device and method for reducing graphene oxide |
| CN114307912A (en) * | 2021-12-29 | 2022-04-12 | 上海大学 | Graphene oxide reduction equipment |
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| CN103147051A (en) * | 2013-03-08 | 2013-06-12 | 南京航空航天大学 | Preparation method of graphene iridium nanometer conductive catalytic film |
| CN106365158A (en) * | 2016-07-15 | 2017-02-01 | 内江师范学院 | Preparation method of graphene oxide, and preparation method of boron-doped reduced graphene oxide |
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Patent Citations (3)
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| CN102698741A (en) * | 2012-04-16 | 2012-10-03 | 中国科学院等离子体物理研究所 | Method for preparing grapheme platinum nanocomposite material by using argon plasma |
| CN103147051A (en) * | 2013-03-08 | 2013-06-12 | 南京航空航天大学 | Preparation method of graphene iridium nanometer conductive catalytic film |
| CN106365158A (en) * | 2016-07-15 | 2017-02-01 | 内江师范学院 | Preparation method of graphene oxide, and preparation method of boron-doped reduced graphene oxide |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109179374A (en) * | 2018-08-17 | 2019-01-11 | 山东重山光电材料股份有限公司 | A kind of method of low temperature preparation fluorinated carbon material |
| CN112391094A (en) * | 2020-11-13 | 2021-02-23 | 天长市京发铝业有限公司 | Aluminum-based plate surface wear-resistant coating and preparation method thereof |
| CN113003567A (en) * | 2021-05-06 | 2021-06-22 | 哈尔滨工程大学 | Device and method for reducing graphene oxide |
| CN113003567B (en) * | 2021-05-06 | 2022-12-13 | 哈尔滨工程大学 | Device and method for reducing graphene oxide |
| CN114307912A (en) * | 2021-12-29 | 2022-04-12 | 上海大学 | Graphene oxide reduction equipment |
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