CN117431063A - Preparation method of graphene quantum dots - Google Patents
Preparation method of graphene quantum dots Download PDFInfo
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- CN117431063A CN117431063A CN202311193616.0A CN202311193616A CN117431063A CN 117431063 A CN117431063 A CN 117431063A CN 202311193616 A CN202311193616 A CN 202311193616A CN 117431063 A CN117431063 A CN 117431063A
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- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 title claims abstract description 47
- 238000002360 preparation method Methods 0.000 title claims abstract description 26
- 238000000034 method Methods 0.000 claims abstract description 31
- 238000005229 chemical vapour deposition Methods 0.000 claims abstract description 10
- 230000008569 process Effects 0.000 claims abstract description 7
- 229910052799 carbon Inorganic materials 0.000 claims abstract description 6
- 239000000758 substrate Substances 0.000 claims description 33
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims description 21
- 238000006243 chemical reaction Methods 0.000 claims description 17
- 229910021389 graphene Inorganic materials 0.000 claims description 16
- 239000002096 quantum dot Substances 0.000 claims description 11
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims description 9
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims description 8
- 230000035484 reaction time Effects 0.000 claims description 6
- 238000000137 annealing Methods 0.000 claims description 5
- 239000012535 impurity Substances 0.000 claims description 5
- 229910052814 silicon oxide Inorganic materials 0.000 claims description 5
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical group [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 claims description 4
- 229910052710 silicon Inorganic materials 0.000 claims description 4
- 239000010703 silicon Substances 0.000 claims description 4
- VGGSQFUCUMXWEO-UHFFFAOYSA-N Ethene Chemical compound C=C VGGSQFUCUMXWEO-UHFFFAOYSA-N 0.000 claims description 3
- 239000005977 Ethylene Substances 0.000 claims description 3
- 238000004140 cleaning Methods 0.000 claims description 3
- 238000001816 cooling Methods 0.000 claims description 3
- 239000012212 insulator Substances 0.000 claims description 3
- 238000010438 heat treatment Methods 0.000 claims description 2
- 235000012239 silicon dioxide Nutrition 0.000 claims description 2
- 239000000377 silicon dioxide Substances 0.000 claims description 2
- 239000007795 chemical reaction product Substances 0.000 claims 1
- 238000004519 manufacturing process Methods 0.000 abstract description 5
- 238000009826 distribution Methods 0.000 abstract description 4
- 125000004432 carbon atom Chemical group C* 0.000 abstract description 3
- 239000002245 particle Substances 0.000 abstract description 3
- 239000003054 catalyst Substances 0.000 abstract description 2
- 125000000524 functional group Chemical group 0.000 abstract description 2
- 230000004048 modification Effects 0.000 abstract description 2
- 238000012986 modification Methods 0.000 abstract description 2
- 238000003912 environmental pollution Methods 0.000 abstract 1
- 239000000523 sample Substances 0.000 description 21
- 239000007789 gas Substances 0.000 description 8
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 3
- 230000009471 action Effects 0.000 description 3
- 239000001257 hydrogen Substances 0.000 description 3
- 229910052739 hydrogen Inorganic materials 0.000 description 3
- 239000002243 precursor Substances 0.000 description 3
- 239000000126 substance Substances 0.000 description 3
- CSCPPACGZOOCGX-UHFFFAOYSA-N Acetone Chemical compound CC(C)=O CSCPPACGZOOCGX-UHFFFAOYSA-N 0.000 description 2
- 239000004215 Carbon black (E152) Substances 0.000 description 2
- KFZMGEQAYNKOFK-UHFFFAOYSA-N Isopropanol Chemical compound CC(C)O KFZMGEQAYNKOFK-UHFFFAOYSA-N 0.000 description 2
- 238000001069 Raman spectroscopy Methods 0.000 description 2
- 238000001237 Raman spectrum Methods 0.000 description 2
- 238000012512 characterization method Methods 0.000 description 2
- 238000005336 cracking Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 229930195733 hydrocarbon Natural products 0.000 description 2
- 150000002430 hydrocarbons Chemical class 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 238000001000 micrograph Methods 0.000 description 2
- 206010028980 Neoplasm Diseases 0.000 description 1
- 239000004793 Polystyrene Substances 0.000 description 1
- 239000002253 acid Substances 0.000 description 1
- 230000003213 activating effect Effects 0.000 description 1
- 230000004931 aggregating effect Effects 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 238000012984 biological imaging Methods 0.000 description 1
- 201000011510 cancer Diseases 0.000 description 1
- 238000003763 carbonization Methods 0.000 description 1
- 230000003749 cleanliness Effects 0.000 description 1
- 238000003776 cleavage reaction Methods 0.000 description 1
- 239000002178 crystalline material Substances 0.000 description 1
- 238000006210 cyclodehydration reaction Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000000151 deposition Methods 0.000 description 1
- 238000012377 drug delivery Methods 0.000 description 1
- 238000000609 electron-beam lithography Methods 0.000 description 1
- 238000006056 electrooxidation reaction Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- ZPDRQAVGXHVGTB-UHFFFAOYSA-N gallium;gadolinium(3+);oxygen(2-) Chemical compound [O-2].[O-2].[O-2].[Ga+3].[Gd+3] ZPDRQAVGXHVGTB-UHFFFAOYSA-N 0.000 description 1
- 238000001027 hydrothermal synthesis Methods 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 229920002223 polystyrene Polymers 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 230000007017 scission Effects 0.000 description 1
- 229910000859 α-Fe Inorganic materials 0.000 description 1
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B82—NANOTECHNOLOGY
- B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
- B82Y40/00—Manufacture or treatment of nanostructures
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B82—NANOTECHNOLOGY
- B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
- B82Y20/00—Nanooptics, e.g. quantum optics or photonic crystals
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B32/00—Carbon; Compounds thereof
- C01B32/15—Nano-sized carbon materials
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- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
- C09K11/00—Luminescent, e.g. electroluminescent, chemiluminescent materials
- C09K11/08—Luminescent, e.g. electroluminescent, chemiluminescent materials containing inorganic luminescent materials
- C09K11/65—Luminescent, e.g. electroluminescent, chemiluminescent materials containing inorganic luminescent materials containing carbon
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- Engineering & Computer Science (AREA)
- Nanotechnology (AREA)
- Organic Chemistry (AREA)
- Materials Engineering (AREA)
- Crystallography & Structural Chemistry (AREA)
- Inorganic Chemistry (AREA)
- Physics & Mathematics (AREA)
- Manufacturing & Machinery (AREA)
- General Physics & Mathematics (AREA)
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- Optics & Photonics (AREA)
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Abstract
The invention relates to the technical field of Graphene Quantum Dots (GQDs) preparation, in particular to a preparation method of graphene quantum dots. Therefore, the size precision control and the band gap control can be realized by controlling the growth environment, the size of a growth sample is limited by the plasma chemical vapor deposition cavity, complex process and high-cost equipment are not needed, and the industrialized mass production of GQDs can be realized. Compared with the bottom-up preparation method in the prior art, the method has the advantages of low growth temperature controlled at 580-730 ℃, no need of catalyst, no modification of other functional groups of the C atom of the sample, no environmental pollution, small particle size, low layer number, controllable distribution, low cost and the like.
Description
Technical Field
The invention relates to the technical field of preparation of Graphene Quantum Dots (GQDs), in particular to a preparation method of graphene quantum dots.
Background
Graphene is a two-dimensional crystalline material composed of closely packed carbon atoms, and has high electron mobility, good thermal conductivity, excellent chemical stability, and excellent mechanical strength. When the size of graphene is reduced below 100 nanometers, the graphene quantum dot is called as graphene quantum dot, has the properties of graphene and quantum dot, has larger specific surface area, and has unique optical, electronic, spin and photoelectric characteristics due to quantum confinement effect and edge effect, and the characteristics can be applied to biological imaging, cancer treatment, temperature sensing, drug delivery, LED (light-emitting diode) converters, photoelectric detectors, solar cells, photoluminescent materials and biosensor manufacturing.
At present, two main methods for preparing graphene quantum dots are mainly top-down and bottom-up. The top-down method comprises electron beam lithography, acid stripping, electrochemical oxidation, microwave assisted hydrothermal synthesis and the like, and a large-size graphene sheet is cut into small-size graphene quantum dots by a physical or chemical method, and the GQDs edge prepared by the method contains rich oxygen-containing groups and can be further chemically modified, but the growth equipment and the preparation conditions are harsh, the preparation process cannot be effectively controlled, and the size and the shape distribution are unstable. The bottom-up method comprises solution chemistry, cyclodehydration of polystyrene precursors, carbonization of specific organic precursors and cleavage of suitable precursors, and the like, and the method involves the participation of solutions, inevitably introduces impurities, and has complicated preparation steps and complex operation.
Therefore, the GQDs preparation method which has the advantages of small particle size, low layer number, controllable distribution, low cost and simple process is developed, and has positive significance for realizing the industrialized mass production of the GQDs.
Disclosure of Invention
The invention aims to provide a preparation method of graphene quantum dots, which is used for improving the quality and cleanliness of the graphene quantum dots.
In order to achieve the above purpose, the invention adopts the following technical scheme:
a preparation method of graphene quantum dots comprises the following steps:
step 1, providing an insulating substrate, cleaning the insulating substrate, and removing impurities and organic matters on the surface of the substrate;
step 2, adopting a plasma chemical vapor deposition method, taking gaseous molecules or steam containing carbon elements as a reaction source, taking the insulating substrate treated in the step 1 as a carrier for growing graphene quantum dots, and carrying out vacuum degree 10 under the plasma power range of 10-50W -3 ～10 -4 And (3) in the environment of the reaction temperature of 580-730 ℃ and the reaction source air pressure value of 16-29 Pa, the reaction time is 5-40 minutes, and then the graphene quantum dot loaded by the insulator is obtained after naturally cooling to room temperature and then taking out.
Further, the step 2 further includes performing an annealing process on the insulating substrate processed in the step 1 before the graphene quantum dots are deposited by plasma chemical vapor deposition, where the annealing process is as follows:
heating to 1000 deg.c, maintaining for 15-25 min, and cooling to growth temperature at 10 deg.c/min to control the temperature of the insulator substrate at 580-730 deg.c.
Further, the insulating substrate is silicon-based silicon oxide, silicon dioxide or a magnetic insulating substrate, preferably a magnetic insulating substrate.
Further, the pressure value of the reaction source in the step 2 is 16-19 Pa.
Further, the reaction source gas in the step 2 is methane, ethylene or ethanol.
The invention provides a preparation method of graphene quantum dots, which utilizes plasma gas-phase reinforced chemical vapor deposition equipment to manufacture graphene quantum dots on an insulating substrate, and the preparation method comprises the following steps: when the reaction source gas is heated to the growth temperature, the reaction source gas is decomposed into hydrocarbon-containing groups and hydrogen under the action of plasma, the hydrocarbon-containing groups and the hydrogen are diffused to a growth substrate area, and the substances are deposited on the surface of the substrate under the combined action of the plasma to form the graphene quantum dots.
Compared with the top-down manufacturing method in the prior art, the method has the advantages that the annealing process is carried out on the insulating substrate before the graphene quantum dots are deposited by the plasma chemical vapor deposition, so that the situation of the silicon wafer before each growth is in the same environment, and a single variable is ensured. Therefore, the size of a growth sample is limited by the plasma chemical vapor deposition cavity only, and the growth sample can directly grow on the surface of 4 inches of silicon oxide, and the preparation process is simpler, has low cost and is suitable for batch growth. Compared with the bottom-up preparation method in the prior art, the preparation method has the advantages that the growth temperature is controlled to be 580-730 ℃, the growth temperature is low, no catalyst is needed, the C atom of the sample is not modified by other functional groups, the preparation method is environment-friendly, the particle size is small, the number of layers is low, the distribution is controllable, the cost is low, and the like, and the quality of the graphene quantum dots is effectively improved.
Drawings
FIG. 1 is a scanning probe microscope image of two graphene quantum dot samples grown under two different conditions prepared in example 1; wherein a is sample one and b is sample two;
FIG. 2 is a Raman spectrum of two graphene quantum dot samples prepared in example 1, where a is sample one and b is sample two;
FIG. 3 is a scanning probe micrograph of graphene quantum dot sample three prepared in example 2;
fig. 4 is a raman spectrum of graphene quantum dot sample three prepared in example 2.
Detailed Description
The technical scheme of the invention is described in detail below with reference to the accompanying drawings and specific embodiments:
the preparation method of the graphene quantum dot provided by the embodiment comprises the following steps:
step 1, selecting an insulating substrate as a growth substrate, and cleaning the substrate in acetone, ethanol and isopropanol by using an ultrasonic method to remove impurities and organic matters on the surface of the substrate, so that the substrate is kept clean and dry.
Step 2, growing graphene quantum dots on an insulating substrate by adopting a deposition method of a plasma chemical vapor deposition method, wherein the specific operation method comprises the following steps:
placing the insulating substrate treated in the step 1 into a growth area of a cavity of plasma chemical vapor deposition equipment, and vacuumizing to 10 -3 ～10 -4 Handkerchief; then hydrogen is introduced, the temperature of the cavity is quickly raised to 1000 ℃ and kept for twenty minutes, and then the temperature is reduced to the growth temperature at a temperature reduction rate of 10 ℃ per minute and kept stable. When the temperature is reduced to the growth temperature and kept stable, introducing a reaction source gas, and controlling the gas pressure value of the gas to be between 16 and 29 Pa; and (3) turning on a plasma power supply, controlling the plasma power range to be between 10 and 50W, cracking the reaction source gas, enabling active groups containing carbon to react under the action of plasma, activating and cracking the active groups containing carbon to form active groups containing carbon, adsorbing, diffusing and aggregating the active groups on a silicon oxide substrate to nucleate, and finally generating the graphene quantum dots. The growth temperature is 580-730 ℃, the reaction source is methane, ethylene or ethanol, and the reaction time is 5-40 minutes.
Example 1
According to the above procedure, samples one and two were prepared using different conditions in this example. In the embodiment, the insulating substrates of the two samples are silicon-based silicon oxide substrates, and the introduced reaction gases are methane. Wherein the preparation conditions of the first sample are as follows: the growth temperature is 600 ℃, the reaction time is 30 minutes, the growth power is 20W, and the growth air pressure is 16 Pa; the preparation conditions of the first sample are as follows: the growth temperature was 610℃and the reaction time was 30 minutes, the growth power was 20W and the growth pressure was 16 Pa. The prepared sample I is shown in fig. 1 (a), the sample II is shown in fig. 1 (b), and the scales of fig. 1 (a) and 1 (b) are 500 nanometers.
Raman characterization was performed on sample one and sample two, respectively, as shown in fig. 2 (a) and fig. 2 (b), and both sample one and sample two can clearly see D, G and 2D peaks of graphene.
Example 2
Sample three was prepared in the same manner as described above, and methane was used as the reaction source in this example, unlike example 1, which uses gadolinium gallium garnet ferrite (GGG) as the insulating substrate, the temperature was controlled at 580-700 ℃, the plasma power was set at 20w, the vacuum was maintained at 10 pa or less, the reaction time was 15 minutes, and the grown graphene quantum dots were as shown in fig. 3.
(2) Raman characterization was performed on sample three, which clearly sees the D, G and 2D peaks of graphene, as shown in fig. 4.
The preparation method of the graphene quantum dot provided by the embodiment can be used for large-area preparation, is simple and easy to realize in preparation steps, and overcomes the defect of a solution method that impurities are more. The method has important significance for exploring the size-controllable growth technology of the graphene quantum dots, understanding the growth mechanism of the graphene quantum dots and exploring the practical application of the graphene quantum dots.
The foregoing is only illustrative of the preferred embodiments of the invention, and it will be appreciated by those skilled in the art that various changes in the features and embodiments may be made and equivalents may be substituted without departing from the spirit and scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed, but that the invention will include all embodiments falling within the scope of the appended claims.
Claims (5)
1. The preparation method of the graphene quantum dot is characterized by comprising the following steps of:
step 1, providing an insulating substrate, cleaning the insulating substrate, and removing impurities and organic matters on the surface of the substrate;
step 2, adopting a plasma chemical vapor deposition method, taking gaseous molecules or steam containing carbon elements as a reaction source, taking the insulating substrate treated in the step 1 as a carrier for growing graphene quantum dots, and carrying out vacuum degree 10 under the plasma power range of 10-50W -3 ～10 -4 The reaction time is 5-40 minutes under the conditions of the reaction temperature of 580-730 ℃ and the reaction source air pressure value of 16-29 Pa, and then the reaction product is naturally cooled to room temperature and taken out to obtainInsulator-supported graphene quantum dots.
2. The method for preparing the graphene quantum dots according to claim 1, wherein the method comprises the following steps:
the step 2 further comprises the step of performing an annealing process on the insulating substrate treated in the step 1 before the graphene quantum dots are deposited by plasma chemical vapor deposition, wherein the annealing process is as follows:
heating to 1000 deg.c, maintaining for 15-25 min, and cooling to growth temperature at 10 deg.c/min to control the temperature of the insulator substrate at 580-730 deg.c.
3. The method for preparing the graphene quantum dots according to claim 1, wherein the method comprises the following steps: the insulating substrate is silicon-based silicon oxide, silicon dioxide or a magnetic insulating substrate, preferably a magnetic insulating substrate.
4. The method for preparing the graphene quantum dots according to claim 1, wherein the method comprises the following steps: the pressure value of the reaction source in the step 2 is 16-19 Pa.
5. The method for preparing the graphene quantum dots according to any one of claims 1 to 4, wherein the method is characterized in that: and the reaction source gas in the step 2 is methane, ethylene or ethanol.
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| Application Number | Priority Date | Filing Date | Title |
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| CN202311193616.0A CN117431063A (en) | 2023-09-15 | 2023-09-15 | Preparation method of graphene quantum dots |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202311193616.0A CN117431063A (en) | 2023-09-15 | 2023-09-15 | Preparation method of graphene quantum dots |
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| CN117431063A true CN117431063A (en) | 2024-01-23 |
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| CN202311193616.0A Pending CN117431063A (en) | 2023-09-15 | 2023-09-15 | Preparation method of graphene quantum dots |
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2023
- 2023-09-15 CN CN202311193616.0A patent/CN117431063A/en active Pending
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