Preparation method of assembly of carbon quantum dots (CQDS)

A technology of carbon quantum dots and assemblies, applied in chemical instruments and methods, photosensitive devices, luminescent materials, etc., can solve the problems of increased binding constant, low hydrogen bond force, low strength, etc., and achieve the effect of high reaction yield

Inactive Publication Date: 2015-04-22
TIANJIN UNIV
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  • Claims
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Problems solved by technology

However, the strength of a single hydrogen bond is relatively small, and its bond energy is within 0-40kJ/mol, which is about one energy level lower than that of a covalent bond, and the hydrogen bond force is greatly affected by the solvent. If the polarity of the solvent i

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  • Preparation method of assembly of carbon quantum dots (CQDS)
  • Preparation method of assembly of carbon quantum dots (CQDS)
  • Preparation method of assembly of carbon quantum dots (CQDS)

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preparation example Construction

[0026] The preparation method of the CQDS assembly of embodiment comprises the following processes:

[0027] 1) Add 10-50μL of concentrated sulfuric acid as an ion catalyst to 5-20ml of 80% glycerol aqueous solution, ultrasonically treat the mixed solution for 3-5 minutes to make it evenly dispersed, and put it in a household microwave oven at high temperature. React for 5-10 minutes; after the reaction, cool the beaker to room temperature, add a small amount of deionized water for ultrasonication, and centrifuge to obtain a black-yellow solution; finally, dialyze and freeze-dry the solution to obtain CQDS solid powder;

[0028] 2) Weigh the quality of the above-mentioned solid powder, and weigh NaBH by 1-5 times the mass equivalent 4 ; Dissolve CQDS powder in NaBH 4 Put the solution into a polytetrafluoroethylene hydrothermal reaction kettle, cover and seal it, put the reaction kettle into a muffle furnace and raise the temperature to 160-220°C to react for 12-24h. After the...

Embodiment 1

[0032] Add 10 μL of concentrated sulfuric acid as an ion catalyst to 5 ml of a glycerol solution with a volume fraction of 80%, disperse it evenly by ultrasonication for 3 minutes, put it into a household microwave reactor and react for 5 minutes, wait to cool to room temperature, add 20 ml of deionized water for ultrasonication, The mixture was centrifuged at 5000r / min for 5min, and the bottom precipitate was removed to obtain a supernatant.

[0033] After concentrating the supernatant and lyophilizing, weigh 100 mg of powdered CQDS, and weigh 100 mg of NaBH 4 Solid; 2 solids were dissolved in water and placed in a 20ml polytetrafluoroethylene hydrothermal kettle, sealed and placed in a muffle furnace and heated to 160°C for 12 hours of reaction. After the end, the solution was dialyzed to neutrality and freeze-dried to obtain Reduced CQDS;

[0034] in N 2 Under protection, weigh 250mg of the small molecule compound UPy containing -NCO and 50mg of reduced lyophilized CQDS, ...

Embodiment 2

[0040] Add 50 μL of concentrated sulfuric acid as an ion catalyst to 15 ml of glucose solution with a volume fraction of 80%, disperse it evenly by ultrasonication for 4 minutes, put it into a household microwave reactor and react for 7 minutes, wait to cool to room temperature, add 20 ml of deionized water and ultrasonicate, and mix The solution was centrifuged at 5000r / min for 5min, and the bottom precipitate was removed to obtain the supernatant.

[0041] After concentrating the supernatant and lyophilizing, weigh 100 mg of powdered CQDS, and weigh 300 mg of NaBH 4 Solid; 2 solids were dissolved in water and placed in a 20ml polytetrafluoroethylene hydrothermal kettle, sealed and placed in a muffle furnace and heated to 190°C for 18 hours of reaction. After the end, the solution was dialyzed to neutrality and freeze-dried to obtain Reduced CQDS;

[0042] in N 2 Under protection, weigh 400 mg of the small molecule compound UPy containing -NCO and 50 mg of reduced-lyophiliz...

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Abstract

The invention provides a preparation method of an assembly of carbon quantum dots (CQDS). A micromolecule carbohydrate is used as a carbon source, and a one-step microwave method is carried out to synthesize the CQDS with sizes of few nanometers; sodium borohydride is used for treating the CQDS, and after epoxy groups and carbanyl groups of surfaces of the CQDS are reduced to hydroxyl groups, the hydroxyl groups are freeze-dried to obtain yellow powder; then, a micromolecule compound UPy containing -NCO groups reacts with the CQDS in anhydrous NMP, chloroform is used for precipitating a product, and the assembly of the carbon quantum dots is obtained after filtering and drying. The obtained CQDS are uniform in size distribution, the assembly is of a spherical structure, and the assembly of the CQDS has strong fluorescence under ultraviolet light. High temperature or high pressure or high vacuum conditions or specially-made reaction instruments are not needed in the whole process, and the reaction yield is high. The assembly overcomes the defect that monodisperse CQDS are small in size, has important significance in achieving large-scale applications of carbon nanomaterials and is expected to be applied to the fields of solar cells, photovoltaic devices, optoelectronic materials and the like.

Description

technical field [0001] The invention relates to a preparation method of a three-dimensional carbon quantum dot assembly, which can be used in dye-sensitized solar cells instead of organic dyes, and belongs to the technical field of carbon nanomaterials. Background technique [0002] With the global energy demand increasing year by year, the energy problem has become a major problem encountered by the global economic development. As a kind of green energy, solar energy is inexhaustible and inexhaustible. It is one of the new energy sources developed and utilized by scientists from all over the world. In 1954, the Bell Research Institute of the United States successfully developed silicon solar cells, creating a precedent for photoelectric conversion research. The follow-up research initially focused on inorganic solar cells, such as monocrystalline silicon and polycrystalline silicon cells. However, due to high cost, complex process, severe photocorrosion of narrow bandgap s...

Claims

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Application Information

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IPC IPC(8): C09K11/65C09K11/02H01G9/20
Inventor 封伟郝竞翔
Owner TIANJIN UNIV
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