CN117587424B - Carbon quantum dot and preparation method and application thereof - Google Patents
Carbon quantum dot and preparation method and application thereof Download PDFInfo
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- CN117587424B CN117587424B CN202410083690.5A CN202410083690A CN117587424B CN 117587424 B CN117587424 B CN 117587424B CN 202410083690 A CN202410083690 A CN 202410083690A CN 117587424 B CN117587424 B CN 117587424B
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- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 title claims abstract description 85
- 238000002360 preparation method Methods 0.000 title claims abstract description 27
- 239000003245 coal Substances 0.000 claims abstract description 72
- 238000000034 method Methods 0.000 claims abstract description 37
- 239000000203 mixture Substances 0.000 claims abstract description 25
- 238000005868 electrolysis reaction Methods 0.000 claims abstract description 23
- 239000002033 PVDF binder Substances 0.000 claims abstract description 18
- 229920002981 polyvinylidene fluoride Polymers 0.000 claims abstract description 18
- 238000002156 mixing Methods 0.000 claims abstract description 15
- 239000007788 liquid Substances 0.000 claims abstract description 9
- 239000012298 atmosphere Substances 0.000 claims abstract description 8
- 238000010000 carbonizing Methods 0.000 claims abstract description 8
- 238000003825 pressing Methods 0.000 claims abstract description 7
- 238000001914 filtration Methods 0.000 claims abstract description 6
- 238000003763 carbonization Methods 0.000 claims description 25
- KWYUFKZDYYNOTN-UHFFFAOYSA-M Potassium hydroxide Chemical compound [OH-].[K+] KWYUFKZDYYNOTN-UHFFFAOYSA-M 0.000 claims description 12
- 239000002802 bituminous coal Substances 0.000 claims description 10
- 238000001035 drying Methods 0.000 claims description 8
- 239000000843 powder Substances 0.000 claims description 8
- 238000004519 manufacturing process Methods 0.000 claims description 7
- 239000011261 inert gas Substances 0.000 claims description 4
- 238000000748 compression moulding Methods 0.000 claims description 3
- 238000000502 dialysis Methods 0.000 claims description 3
- 230000008569 process Effects 0.000 claims description 3
- 238000001704 evaporation Methods 0.000 claims description 2
- 238000004108 freeze drying Methods 0.000 claims description 2
- 230000000630 rising effect Effects 0.000 claims description 2
- 239000003792 electrolyte Substances 0.000 abstract description 9
- 239000002699 waste material Substances 0.000 abstract description 3
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 14
- 239000000243 solution Substances 0.000 description 14
- 229910052799 carbon Inorganic materials 0.000 description 11
- 239000002994 raw material Substances 0.000 description 11
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 8
- 239000007787 solid Substances 0.000 description 8
- 230000000052 comparative effect Effects 0.000 description 7
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 description 6
- 238000007254 oxidation reaction Methods 0.000 description 6
- 238000006243 chemical reaction Methods 0.000 description 5
- 239000002245 particle Substances 0.000 description 5
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 4
- 229910052757 nitrogen Inorganic materials 0.000 description 4
- 230000003647 oxidation Effects 0.000 description 4
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Chemical compound [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 description 4
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 4
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 3
- 230000009286 beneficial effect Effects 0.000 description 3
- 230000005540 biological transmission Effects 0.000 description 3
- 238000006056 electrooxidation reaction Methods 0.000 description 3
- 238000005516 engineering process Methods 0.000 description 3
- 239000000463 material Substances 0.000 description 3
- 238000003801 milling Methods 0.000 description 3
- 239000012299 nitrogen atmosphere Substances 0.000 description 3
- 239000000126 substance Substances 0.000 description 3
- NLXLAEXVIDQMFP-UHFFFAOYSA-N Ammonia chloride Chemical compound [NH4+].[Cl-] NLXLAEXVIDQMFP-UHFFFAOYSA-N 0.000 description 2
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- WCUXLLCKKVVCTQ-UHFFFAOYSA-M Potassium chloride Chemical compound [Cl-].[K+] WCUXLLCKKVVCTQ-UHFFFAOYSA-M 0.000 description 2
- 238000001069 Raman spectroscopy Methods 0.000 description 2
- WYURNTSHIVDZCO-UHFFFAOYSA-N Tetrahydrofuran Chemical compound C1CCOC1 WYURNTSHIVDZCO-UHFFFAOYSA-N 0.000 description 2
- 238000004833 X-ray photoelectron spectroscopy Methods 0.000 description 2
- 238000002835 absorbance Methods 0.000 description 2
- 238000004458 analytical method Methods 0.000 description 2
- 239000007864 aqueous solution Substances 0.000 description 2
- 238000012512 characterization method Methods 0.000 description 2
- KRKNYBCHXYNGOX-UHFFFAOYSA-N citric acid Chemical compound OC(=O)CC(O)(C(O)=O)CC(O)=O KRKNYBCHXYNGOX-UHFFFAOYSA-N 0.000 description 2
- 238000005520 cutting process Methods 0.000 description 2
- 238000009826 distribution Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000002848 electrochemical method Methods 0.000 description 2
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- 238000012986 modification Methods 0.000 description 2
- 239000002086 nanomaterial Substances 0.000 description 2
- 230000003287 optical effect Effects 0.000 description 2
- 229910052697 platinum Inorganic materials 0.000 description 2
- 239000011148 porous material Substances 0.000 description 2
- 230000002035 prolonged effect Effects 0.000 description 2
- 239000002096 quantum dot Substances 0.000 description 2
- 239000004065 semiconductor Substances 0.000 description 2
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- 238000001228 spectrum Methods 0.000 description 2
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- 238000000967 suction filtration Methods 0.000 description 2
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- 238000004627 transmission electron microscopy Methods 0.000 description 2
- 238000002211 ultraviolet spectrum Methods 0.000 description 2
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 description 1
- VEXZGXHMUGYJMC-UHFFFAOYSA-M Chloride anion Chemical compound [Cl-] VEXZGXHMUGYJMC-UHFFFAOYSA-M 0.000 description 1
- 238000005033 Fourier transform infrared spectroscopy Methods 0.000 description 1
- 238000004566 IR spectroscopy Methods 0.000 description 1
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 description 1
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 description 1
- PTFCDOFLOPIGGS-UHFFFAOYSA-N Zinc dication Chemical compound [Zn+2] PTFCDOFLOPIGGS-UHFFFAOYSA-N 0.000 description 1
- 235000019270 ammonium chloride Nutrition 0.000 description 1
- 229960004543 anhydrous citric acid Drugs 0.000 description 1
- 238000013459 approach Methods 0.000 description 1
- 239000011230 binding agent Substances 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 238000004061 bleaching Methods 0.000 description 1
- 239000003990 capacitor Substances 0.000 description 1
- 239000011852 carbon nanoparticle Substances 0.000 description 1
- 239000002041 carbon nanotube Substances 0.000 description 1
- 229910021393 carbon nanotube Inorganic materials 0.000 description 1
- 239000003575 carbonaceous material Substances 0.000 description 1
- 239000003054 catalyst Substances 0.000 description 1
- 238000006555 catalytic reaction Methods 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 239000011294 coal tar pitch Substances 0.000 description 1
- 238000002485 combustion reaction Methods 0.000 description 1
- 230000006835 compression Effects 0.000 description 1
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- 238000005265 energy consumption Methods 0.000 description 1
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- 238000003912 environmental pollution Methods 0.000 description 1
- 238000005530 etching Methods 0.000 description 1
- 230000002349 favourable effect Effects 0.000 description 1
- 238000012921 fluorescence analysis Methods 0.000 description 1
- 238000001506 fluorescence spectroscopy Methods 0.000 description 1
- 239000000295 fuel oil Substances 0.000 description 1
- 238000002309 gasification Methods 0.000 description 1
- 229910021389 graphene Inorganic materials 0.000 description 1
- 229910002804 graphite Inorganic materials 0.000 description 1
- 239000010439 graphite Substances 0.000 description 1
- 238000005087 graphitization Methods 0.000 description 1
- 238000000227 grinding Methods 0.000 description 1
- 125000000623 heterocyclic group Chemical group 0.000 description 1
- 238000011065 in-situ storage Methods 0.000 description 1
- 229910052500 inorganic mineral Inorganic materials 0.000 description 1
- 150000002500 ions Chemical class 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 239000012263 liquid product Substances 0.000 description 1
- 231100000053 low toxicity Toxicity 0.000 description 1
- 238000001000 micrograph Methods 0.000 description 1
- 238000000465 moulding Methods 0.000 description 1
- 229910000510 noble metal Inorganic materials 0.000 description 1
- 239000007800 oxidant agent Substances 0.000 description 1
- 230000001590 oxidative effect Effects 0.000 description 1
- 238000005424 photoluminescence Methods 0.000 description 1
- 238000006068 polycondensation reaction Methods 0.000 description 1
- 235000015497 potassium bicarbonate Nutrition 0.000 description 1
- 229910000028 potassium bicarbonate Inorganic materials 0.000 description 1
- 239000011736 potassium bicarbonate Substances 0.000 description 1
- 239000001103 potassium chloride Substances 0.000 description 1
- 235000011164 potassium chloride Nutrition 0.000 description 1
- TYJJADVDDVDEDZ-UHFFFAOYSA-M potassium hydrogencarbonate Chemical compound [K+].OC([O-])=O TYJJADVDDVDEDZ-UHFFFAOYSA-M 0.000 description 1
- JMTCDHVHZSGGJA-UHFFFAOYSA-M potassium hydrogenoxalate Chemical compound [K+].OC(=O)C([O-])=O JMTCDHVHZSGGJA-UHFFFAOYSA-M 0.000 description 1
- 239000002244 precipitate Substances 0.000 description 1
- 238000000197 pyrolysis Methods 0.000 description 1
- 230000035484 reaction time Effects 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 238000012216 screening Methods 0.000 description 1
- 238000007493 shaping process Methods 0.000 description 1
- 239000010117 shenhua Substances 0.000 description 1
- 238000007873 sieving Methods 0.000 description 1
- 238000010025 steaming Methods 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 229910052717 sulfur Inorganic materials 0.000 description 1
- 239000011593 sulfur Substances 0.000 description 1
- 238000010998 test method Methods 0.000 description 1
- YLQBMQCUIZJEEH-UHFFFAOYSA-N tetrahydrofuran Natural products C=1C=COC=1 YLQBMQCUIZJEEH-UHFFFAOYSA-N 0.000 description 1
- 239000002341 toxic gas Substances 0.000 description 1
- 238000000870 ultraviolet spectroscopy Methods 0.000 description 1
- 238000005406 washing Methods 0.000 description 1
- 229910052724 xenon Inorganic materials 0.000 description 1
- FHNFHKCVQCLJFQ-UHFFFAOYSA-N xenon atom Chemical compound [Xe] FHNFHKCVQCLJFQ-UHFFFAOYSA-N 0.000 description 1
- 239000011701 zinc Substances 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25B—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES FOR THE PRODUCTION OF COMPOUNDS OR NON-METALS; APPARATUS THEREFOR
- C25B1/00—Electrolytic production of inorganic compounds or non-metals
- C25B1/01—Products
- C25B1/135—Carbon
-
- 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
-
- 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
-
- 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
- C01B32/05—Preparation or purification of carbon not covered by groups C01B32/15, C01B32/20, C01B32/25, C01B32/30
-
- 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
-
- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25B—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES FOR THE PRODUCTION OF COMPOUNDS OR NON-METALS; APPARATUS THEREFOR
- C25B1/00—Electrolytic production of inorganic compounds or non-metals
- C25B1/50—Processes
-
- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25B—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES FOR THE PRODUCTION OF COMPOUNDS OR NON-METALS; APPARATUS THEREFOR
- C25B11/00—Electrodes; Manufacture thereof not otherwise provided for
- C25B11/04—Electrodes; Manufacture thereof not otherwise provided for characterised by the material
Abstract
The invention discloses a carbon quantum dot and a preparation method and application thereof. The preparation method of the carbon quantum dot comprises the following steps: (1) Carbonizing the screened coal liquefaction residues in inert atmosphere at 950-1500 ℃ to obtain carbonized coal liquefaction residues; (2) Mixing 0.9 to 3 parts by weight of carbonized coal liquefaction residues obtained in the step (1) with 0.09 to 0.3 part by weight of polyvinylidene fluoride to form a mixture; (3) Pressing and forming the mixture to obtain a coal-based electrode; (4) And (3) placing the coal-based electrode in alkaline electrolyte for electrolysis for 10-40 hours, collecting liquid, and filtering to obtain a carbon quantum dot solution. The method not only can prepare the carbon quantum dots with high added value, but also can realize the maximum utilization of the coal waste resources. Meanwhile, the preparation method has the characteristics of high preparation purity, simplicity, easiness in implementation, cleanness, no pollution and the like.
Description
Technical Field
The invention relates to a carbon quantum dot and a preparation method and application thereof.
Background
The carbon quantum dot is a novel sphere-like carbon nano particle with fluorescent property, the size of which is smaller than 10 nm, the light-emitting range of the small-size fluorescent material is adjustable, the light stability is good, besides the excellent photoluminescence performance of the traditional semiconductor quantum dot, the carbon quantum dot has the advantages of low toxicity, good biocompatibility, high chemical stability, strong light bleaching resistance, easiness in surface modification and the like, and the carbon quantum dot becomes an ideal substitute material of the traditional semiconductor quantum dot, and has wide application prospect in the fields of biomedical treatment, photoelectric materials, ion detection, photoelectric catalysis and the like.
In the direct coal liquefaction process, about 30% of liquefied residue is produced, and the main components of the liquefied residue are heavy oil, asphaltene, pre-asphaltene, unreacted coal (also called tetrahydrofuran insoluble matter), inorganic mineral substances and residual iron-based catalyst, which are substances with high carbon, high ash and high sulfur. Conventional coal liquefaction residue utilization approaches include, but are not limited to, gasification, combustion, etc., which fail to fully utilize the unique fused ring, heterocyclic structure and other large amounts of valuable organic carbon components in the liquefaction residue, and direct disposal can result in wasted resources and environmental pollution. From the viewpoints of the overall economy, resource utilization and environmental protection of direct coal liquefaction, the components are fully utilized to prepare the novel carbon material so as to realize the high-value conversion of coal liquefaction residues.
Currently, the preparation methods of carbon dots include bottom-up and top-down methods. The method adopts small molecular organic matters and the like as carbon sources from bottom to top, and the carbon quantum dots are finally synthesized by a series of changes such as polycondensation reaction and the like through reaction operations such as dehydration, carbonization and the like. The top-down method generally adopts graphite, graphene or carbon nano tube with a macromolecular structure as a carbon source, and the macromolecular structure of the carbon source is partially degraded or modified by means of oxidization, etching and the like, so that the carbon quantum dot is prepared.
CN116835570A discloses a preparation method of a carbon quantum dot nanomaterial. The method comprises the following steps: (1) Anhydrous citric acid and Na 2 SO 4 Mixing and pyrolyzing to obtain a brown-black solid; (2) Dissolving the brown-black solid in water, then dropwise adding NaOH solution, and adjusting the pH to 7 to obtain a mixed solution; (3) Adding ethanol into the mixed solution, stirring and mixing, standing, taking the black viscous liquid at the lower layer, adding water for dilution, adding ethanol and stirring and mixing, and dripping the black viscous liquid into methanol after repeated times to form brown precipitate; washing with methanol after suction filtration, repeating suction filtration for a plurality of times, and then drying the obtained solid in vacuum to obtain the carbon quantum dot nanomaterial. The method adopts a bottom-up method, and the strong oxidant has high use concentration and high risk; toxic gases may be generated during the preparation process, and the preparation process is relatively complex.
CN112095113a discloses a method for preparing carbon quantum dots by using coal as raw material. The method prepares coal powder and aqueous solution containing chloride ions into coal water slurry, and directly oxidizes the coal water slurry by adopting an electrochemical method to prepare the carbon quantum dots. Although the electrochemical method is adopted to prepare the carbon dots, noble metals are used as working electrodes, the cost is high, and the yield of the carbon quantum dots is low.
CN 116374996a discloses a preparation method of nitrogen-doped carbon quantum dots. The method comprises the steps of mixing coal tar pitch as a carbon source, potassium chloride as a template and a mixture of potassium hydrogen oxalate and potassium bicarbonate as a cutting agent in a solid state, utilizing ammonia gas generated by decomposing ammonium chloride as a nitrogen source, and preparing the nitrogen doped carbon quantum dot with the specific surface area of 966.9-1772.7m by utilizing an in-situ doping and limited-area cutting technology under the protection of inert gas 2 Per gram, total pore volume of 1.43-2.35cm 3 The nitrogen content per gram is 2.83-5.42%; zinc foil is used as negative electrode, 1mol/L Zn (ClO) 4 ) 2 When the solution is electrolyte and the zinc ion mixed capacitor is assembled, the capacity of the solution can reach 144.8mAh/g. The preparation process of the method is complex.
Disclosure of Invention
Accordingly, an object of the present invention is to provide a method for preparing carbon quantum dots, which not only can prepare carbon quantum dots with high added value, but also can obtain carbon quantum dots with high yield. In addition, the maximum utilization of the coal waste resources is realized. Another object of the present invention is to provide a carbon quantum dot. It is still another object of the present invention to provide an application of a coal-based electrode in preparing carbon quantum dots.
The technical aim is achieved through the following technical scheme.
In one aspect, the invention provides a method for preparing carbon quantum dots, comprising the following steps:
(1) Carbonizing the screened coal liquefaction residues in inert atmosphere at 950-1500 ℃ to obtain carbonized coal liquefaction residues;
(2) Mixing 0.9 to 3 parts by weight of carbonized coal liquefaction residues obtained in the step (1) with 0.09 to 0.3 part by weight of polyvinylidene fluoride to form a mixture;
(3) Pressing and forming the mixture to obtain a coal-based electrode;
(4) And (3) placing the coal-based electrode in alkaline electrolyte for electrolysis for 10-40 hours, collecting liquid, and filtering to obtain a carbon quantum dot solution.
According to the production method of the present invention, preferably, in the step (1), the carbonization temperature is 1000 to 1400 ℃.
According to the production method of the present invention, preferably, the flow rate of the inert gas is 100 to 300mL/min; the temperature rising rate from room temperature to carbonization temperature is 5-20 ℃/min.
According to the production method of the present invention, preferably, the carbonized coal liquefaction residue obtained in the step (1) including 0.9 to 3 parts by weight and 0.09 to 0.3 parts by weight of polyvinylidene fluoride are mixed and ground to form a mixture.
According to the production method of the present invention, preferably, in the step (3), the compression molding is performed on a tablet press, and the tablet strength is 15 to 25MPa.
According to the production method of the present invention, preferably, the alkaline electrolyte is a potassium hydroxide solution; the concentration of the potassium hydroxide solution is 1-3 mol/L.
The preparation method according to the present invention preferably further comprises the steps of:
and (3) dialyzing, spin-evaporating and drying the carbon quantum dot solution to obtain solid powder, wherein the powder is the carbon quantum dot.
According to the preparation method of the present invention, preferably, the dialysis time is 2 to 4 days; freeze drying is adopted for drying; the drying time is 20-30 h.
On the other hand, the invention provides the carbon quantum dot prepared by the method.
In still another aspect, the invention provides an application of a coal-based electrode in preparing carbon quantum dots, wherein the coal-based electrode is placed in alkaline electrolyte for electrolysis, and then liquid is collected and filtered to obtain carbon quantum dot solution; wherein, the coal-based electrode is prepared by the following steps:
(1) Carbonizing the screened coal liquefaction residues in inert atmosphere at 950-1500 ℃ to obtain carbonized coal liquefaction residues;
(2) Mixing 0.9 to 3 parts by weight of carbonized coal liquefaction residues obtained in the step (1) with 0.09 to 0.3 part by weight of polyvinylidene fluoride to form a mixture;
(3) And (3) pressing and forming the mixture to obtain the coal-based electrode.
Compared with the preparation method of the carbon quantum dots in the prior art, the preparation method has the following beneficial effects:
(1) According to the preparation method of the carbon quantum dots, residues after coal liquefaction, which are rich in coal reserves in China, are used as main raw materials to prepare the carbon quantum dots with high added value, and meanwhile, the maximum utilization of coal waste resources is realized.
(2) The electrode required for preparing the carbon dots is constructed by taking the coal liquefaction residues and PVDF as raw materials in proper proportion, and the carbon quantum dots are prepared by adopting an electrochemical oxidation method, so that the preparation method has the characteristics of high preparation purity, simplicity and easiness in operation, cleanness, no pollution and the like.
Drawings
Fig. 1 is a distribution histogram of solid yields of carbon quantum dots of examples 1 to 7 and comparative examples 1 to 2.
Fig. 2 is an ultraviolet spectrum of the carbon quantum dots of examples 1 to 3 and comparative examples 1 to 2.
FIG. 3 is a graph showing fluorescence spectra of carbon quantum dots of examples 1 to 3 and comparative examples 1 to 2.
Fig. 4 is an ultraviolet spectrum of the carbon quantum dots of examples 1 and 4 to 7.
FIG. 5 is a fluorescence spectrum of the carbon quantum dots of examples 1 and 4 to 7.
Fig. 6 (a) is a transmission electron microscope image of the carbon quantum dot of example 1; fig. 6 (b) is a particle size distribution histogram of the carbon quantum dots of example 1.
Detailed Description
The invention will be described in more detail below, but is not limited thereto.
< method for producing carbon Quantum dot >
The preparation method of the carbon quantum dot comprises the following steps: (1) a carbonization step; (2) a step of forming a mixture; (3) a molding step; (4) an electrolysis step. The following is a detailed description.
Carbonization step
Carbonizing the sieved liquefied residue, and improving the graphitization degree of the liquefied residue to obtain the raw material for preparing the electrode slice.
The carbonization treatment is performed in an inert atmosphere. Preferably, the inert atmosphere is a nitrogen atmosphere. The nitrogen atmosphere can still keep inert under the high temperature condition, is favorable for carbonization, and improves the durability of the electrode plate.
The carbonization temperature can be 950-1500 ℃; preferably 1000 to 1400 ℃; more preferably 1200 to 1300 ℃. Thus being beneficial to improving the carbonization degree of the electrode plate and the conductivity, and being more suitable for generating more carbon quantum dots by electrolytic oxidation.
The carbonization time can be 2-5 h; preferably 2.5 to 4.5 hours; more preferably 3 to 4 hours. Thus being beneficial to improving the carbonization degree of the electrode plate and being more suitable for generating more carbon quantum dots by electrolytic oxidation.
The temperature rise rate from the room temperature (e.g., 25 ℃) to the carbonization temperature (e.g., 950-1500 ℃) may be 5-20 ℃/min; preferably 8-18 ℃/min; more preferably 9 to 15 ℃/min.
The flow rate of the inert gas is 100-300 mL/min; preferably 150 to 250 mL/min; more preferably 180 to 220 mL/min.
Step of forming a mixture
The mixture is formed by the carbonized coal liquefaction residues and polyvinylidene fluoride raw materials. The invention takes carbonized coal liquefaction residues as raw materials, polyvinylidene fluoride (PVDF) as a binder, electrodes are obtained by pyrolysis and coforming, and liquid products are prepared by electrolytic oxidation.
In the invention, the dosage of the coal liquefaction residue after carbonization treatment is 0.9 to 3 parts by weight; preferably 1 to 2.5 parts by weight; more preferably 1 to 1.5 parts by weight. Thus, a sufficient carbon source can be provided, the progress of the oxidation reaction is ensured, and an electrode with proper pore structure and strength can be obtained, thereby reducing potential and energy consumption.
In the present invention, the coal liquefaction residue is preferably a residue after the bituminous coal liquefaction process. The particle size of the coal liquefaction residue may be 200 to 400 mesh. The coal liquefaction residue of such particle size is more advantageous for forming the desired coal-based electrode.
In the invention, the dosage of the polyvinylidene fluoride is 0.09 to 0.3 weight part; preferably 0.1 to 0.25 parts by weight; more preferably 0.1 to 0.15 parts by weight. This can provide the formed coal-based electrode with appropriate strength and improve the durability of the electrode.
In the present invention, the raw materials may be mixed by an aqueous solution mixing method, a milling mixing method, or a mechanical mixing method to form a mixture. Preferably, a milling mixing method is employed. Specifically, mixing coal liquefaction residues after carbonization and secondary screening with PVDF to obtain a mixture; the mixture was ground.
The milling time may be 5 to 10 minutes, preferably 5 to 8 minutes. This can make the raw materials mix more evenly.
Step of shaping
And (3) pressing and forming the mixture to obtain the coal-based electrode. Compression molding may be performed on a tablet press. The tablet press may be an infrared tablet press. The tabletting strength can be 15-25 MPa; preferably 18-23 MPa; more preferably 20 to 22MPa.
Electrolytic step
And (3) placing the coal-based electrode in alkaline electrolyte for electrolysis, collecting liquid, and filtering to obtain the carbon quantum dot solution.
In the invention, the prepared coal-based electrode is taken as an anode, a platinum electrode plate is taken as a cathode, KOH solution is taken as electrolyte, and the electrochemical oxidation is carried out to prepare the carbon quantum dot, wherein the voltage can be 1.80V.
In the present invention, alkaline conditions are important conditions for electrochemical oxidation to form carbon quantum dots. The alkaline electrolyte is preferably a potassium hydroxide solution. The concentration of the potassium hydroxide solution is preferably 1 to 3mol/L; more preferably 1.5 to 2.5mol/L. This is more advantageous for the formation of carbon quantum dots.
In the invention, the electrolysis time can be 10 to 50 hours; preferably 20 to 45 hours; more preferably 35 to 40 hours. With the progress of electrolysis, the electrolyte solution turns yellow gradually from colorless and finally turns yellow brown, which indicates that the carbon quantum dots are peeled off from the electrode, and the carbon quantum dots are formed. The yield of the carbon quantum dots can be improved under the electrolysis condition.
In the invention, the carbon quantum dot solution can be directly characterized by adopting an ultraviolet-visible spectrophotometry and a fluorescence spectrometry. The carbon quantum dot solution can be further dialyzed, steamed and dried to obtain solid powder for subsequent application. The solid powder is characterized by fourier infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), raman spectroscopy (Raman) or Transmission Electron Microscopy (TEM).
In the present invention, the dialysis time is preferably 2 to 4 days; more preferably 2.5 to 3.5 days. The spin steaming time is preferably 15-30 min; more preferably 15 to 25 minutes. The drying time is preferably 20 to 30 hours; more preferably 22 to 26 hours.
< coal-based electrode and application thereof >
The invention also provides application of the coal-based electrode in preparation of the carbon quantum dots. In the prior art, carbon dots are prepared by a bottom-up and top-down method, and details are detailed in the background art and are not repeated here. There are few technologies for preparing carbon quantum dots by an electrolytic method, and in particular, technologies for preparing carbon quantum dots by using a coal-based electrode as an electrode sheet. Further, there is no method for preparing an electrode that can be used for producing carbon quantum dots using residues after coal liquefaction as a raw material. The invention unexpectedly discovers that carbon quantum dots can be prepared by adopting a specific coal-based electrode, and the coal-based electrode is prepared by the following method:
(1) Carbonizing the screened coal liquefaction residues in inert atmosphere at 950-1500 ℃ to obtain carbonized coal liquefaction residues;
(2) Mixing 0.9 to 3 parts by weight of carbonized coal liquefaction residues obtained in the step (1) with 0.09 to 0.3 part by weight of polyvinylidene fluoride to form a mixture;
(3) And (3) pressing and forming the mixture to obtain the coal-based electrode.
The yield of the carbon quantum dots prepared by the coal-based electrode is not lower than 9.5 and mg; preferably, the yield is not lower than 12 mg; more preferably, the yield is not lower than 27 mg. According to a specific embodiment of the invention, the yield can be up to 68mg (i.e. 13.6% yield).
The following raw materials and test methods are presented:
raw materials
(1) Coal liquefaction residue: residue after the bituminous coal was liquefied was obtained from China's Shenhua energy Co., ltd.
(2) Polyvinylidene fluoride (PVDF): purchased from Shanghai Seiki Biotech Co.
Carbon quantum dot testing/characterization method
(1) Analysis of optical Properties: the optical characteristics of the carbon quantum dot solution were qualitatively detected using a UV-1800 UV-vis spectrometer produced in japan. The spectrum scanning range is 200-600nm, and the resolution is 0.1nm.
(2) Fluorescence analysis: the fluorescence properties of the carbon quantum dot solution were measured using an RF-6000 fluorescence spectrophotometer manufactured by japan. The test light source is a 150W xenon lamp, the detector PMT is selected to be Low, and the spectrum scanning range is 280-380nm.
(3) TEM analysis: the carbon quantum dots were analyzed using an F200X-type field emission transmission electron microscope manufactured by Talos.
(4) The yield of the carbon quantum dots is calculated according to the formula:
y—carbon quantum dot yield (%);
m-collecting the mass (g) of the carbon quantum dots;
m-coal-based electrode plate mass involved in the reaction (g).
Example 1
Grinding the coal liquefaction residues, and sieving by adopting a standard sieve with 200 meshes to obtain the sieved coal liquefaction residues with the particle size of less than or equal to 200 meshes. Carbonizing the sieved coal liquefaction residues for 3 hours under a nitrogen atmosphere with a nitrogen flow rate of 200mL/min and at a temperature of 1200 ℃ to obtain carbonized coal liquefaction residues.
The carbonized coal liquefaction residue 1 part by weight obtained above and polyvinylidene fluoride (PVDF) powder 0.1 part by weight were mixed and ground to form a mixture, and the mixture was compression molded with a tablet press at a tablet strength of 22MPa to obtain a coal-based electrode.
The prepared coal-based electrode is taken as an anode, a platinum electrode plate is taken as a cathode, and a KOH solution of 2mol/L is taken as electrolyte to construct an electrolytic oxidation preparation carbon dot system: the electrolytic tank is placed at room temperature, liquid is collected after electrolysis for 10 hours, and carbon quantum dot solution is obtained through filtration and is characterized. Wherein, during electrolysis, the voltage is 1.8V, and the coal-based electrode participating in the reaction is 0.5g.
Example 2
The procedure of example 1 was repeated except that the carbonization temperature was 1000 ℃.
Example 3
The procedure of example 1 was repeated except that the carbonization temperature was 1400 ℃.
Example 4
The procedure of example 1 was repeated except that the electrolysis time was set to 20 hours.
Example 5
The procedure of example 1 was repeated except that the electrolysis time was set to 30 hours.
Example 6
The procedure of example 1 was repeated except that the electrolysis time was 40 hours.
Example 7
The procedure of example 1 was repeated except that the electrolysis time was set to 50 hours.
Comparative example 1
The procedure of example 1 was repeated except that the carbonization temperature was set at 600 ℃.
Comparative example 2
The procedure of example 1 was repeated except that the carbonization temperature was set to 900 ℃.
The characterization results are shown in table 1.
TABLE 1
Sequence number | Carbonization temperature/. Degree.C | Electrolysis time | Yield/mg | Yield/% |
Example 1 | 1200 | 10 | 12.25 | 2.45 |
Example 2 | 1000 | 10 | 10.08 | 2.02 |
Example 3 | 1400 | 10 | 10.22 | 2.04 |
Example 4 | 1200 | 20 | 27.79 | 5.56 |
Example 5 | 1200 | 30 | 60.74 | 12.15 |
Example 6 | 1200 | 40 | 68.31 | 13.66 |
Example 7 | 1200 | 50 | 55.26 | 11.05 |
Comparative example 1 | 600 | 10 | 0 | 0 |
Comparative example 2 | 900 | 10 | 9.52 | 1.90 |
The carbonization temperature and the electrolysis time have obvious influence on the preparation of carbon points from the coal liquefaction residues. When the electrolysis time is the same, as can be seen from fig. 1, 2, 3 and table 1, the absorbance and fluorescence intensity both show a tendency to increase and decrease, and are basically strongest at the carbonization temperature of 1200 ℃, at which electrochemical activity and conductivity are relatively good, and the yield of the carbon dots is maximum under the relatively same conditions. In combination with the high carbonization temperature, 1200 ℃ is a relatively optimal condition. When the carbonization temperature is out of the range of the present invention, it is difficult to form carbon quantum dots or the yield of carbon quantum dots is low.
When the carbonization temperature was the same, as can be seen from fig. 1, 4, 5 and table 1, the absorbance and fluorescence intensity also tended to increase and decrease, and were basically strongest at an electrolysis time of 40h. With the increase of the reaction time, the yield of the carbon quantum dots is gradually increased, and reaches 68.31mg by 40h. If the electrolysis time is prolonged, the yield is reduced to a certain extent, the damage degree to the carbon structure of the liquefied residue is larger because 40h is the degree of complete reaction, and if the electrolysis time is prolonged, the damage to the carbon point part structure or the activity reduction of the electrode plate may exist, and the promotion of the electrolysis degree is limited.
The carbon quantum dot transmission electron microscope chart of example 1 is shown in fig. 6, and it can be found that the carbon quantum dots prepared by the preparation method of the invention are uniformly distributed, the particle size is narrower and is 0.5-4.5 nm, and the average diameter is 2.86nm.
The present invention is not limited to the above-described embodiments, and any modifications, improvements, substitutions, and the like, which may occur to those skilled in the art, fall within the scope of the present invention without departing from the spirit of the invention.
Claims (8)
1. The preparation method of the carbon quantum dot is characterized by comprising the following steps of:
(1) Carbonizing the sieved bituminous coal liquefaction residues in inert atmosphere at the temperature of 1000-1400 ℃ to obtain carbonized bituminous coal liquefaction residues;
(2) Mixing 0.9 to 3 parts by weight of carbonized bituminous coal liquefaction residues obtained in the step (1) with 0.09 to 0.3 part by weight of polyvinylidene fluoride to form a mixture;
(3) Pressing and forming the mixture to obtain a coal-based electrode;
(4) And (3) placing the coal-based electrode in a 1.5-2.5 mol/L potassium hydroxide solution for electrolysis for 10-40 hours, collecting liquid, and filtering to obtain a carbon quantum dot solution.
2. The method according to claim 1, wherein the flow rate of the inert gas is 100 to 300mL/min; the temperature rising rate from room temperature to carbonization temperature is 5-20 ℃/min.
3. The method according to claim 1, wherein the carbonized bituminous coal liquefaction residue obtained in step (1) comprising 0.9 to 3 parts by weight and 0.09 to 0.3 parts by weight of polyvinylidene fluoride are mixed and ground to form a mixture.
4. The process according to claim 1, wherein in the step (3), the compression molding is performed on a tablet press, and the tablet strength is 15 to 25MPa.
5. The preparation method of claim 1, further comprising dialyzing, spin-evaporating and drying the carbon quantum dot solution to obtain a powder, wherein the powder is the carbon quantum dot.
6. The method according to claim 5, wherein the dialysis time is 2 to 4 days; the freeze drying is adopted for drying, and the drying time is 20-30 hours.
7. A carbon quantum dot, characterized in that it is produced by the production method according to any one of claims 5 to 6.
8. The application of the bituminous coal liquefaction residues in preparing the carbon quantum dots is characterized by comprising the following steps:
(1) Carbonizing the sieved bituminous coal liquefaction residues in inert atmosphere at the temperature of 1000-1400 ℃ to obtain carbonized bituminous coal liquefaction residues;
(2) Mixing 0.9 to 3 parts by weight of carbonized bituminous coal liquefaction residues obtained in the step (1) with 0.09 to 0.3 part by weight of polyvinylidene fluoride to form a mixture;
(3) Pressing and forming the mixture to obtain a coal-based electrode;
(4) And (3) placing the coal-based electrode in a 1.5-2.5 mol/L potassium hydroxide solution for electrolysis for 10-40 hours, collecting liquid, and filtering to obtain a carbon quantum dot solution.
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CN105586036A (en) * | 2016-01-25 | 2016-05-18 | 大连理工大学 | Preparation method of nitrogen-doped fluorescent carbon dots |
KR20190016354A (en) * | 2017-08-08 | 2019-02-18 | 대구대학교 산학협력단 | Manufacturing method of carbon quantum dots by electrochemical method and manufacturing method of carbon quantum dots-silver nano particle using the same |
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KR20190016354A (en) * | 2017-08-08 | 2019-02-18 | 대구대학교 산학협력단 | Manufacturing method of carbon quantum dots by electrochemical method and manufacturing method of carbon quantum dots-silver nano particle using the same |
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