Silicon quantum dot aqueous phase preparation method

A technology for the preparation of silicon quantum dots and water phase, which is applied in chemical instruments and methods, nanotechnology, nano-optics, etc., can solve problems such as low quantum yield, and achieve the effects of simple synthesis operation, easy availability of raw materials, and cheap raw materials

Inactive Publication Date: 2016-09-28
SOUTH CENTRAL UNIVERSITY FOR NATIONALITIES
View PDF2 Cites 12 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0004] The technical problem to be solved in the present invention is that the existing method prepares silicon quantum dots, and the quantum yield is low

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Silicon quantum dot aqueous phase preparation method
  • Silicon quantum dot aqueous phase preparation method
  • Silicon quantum dot aqueous phase preparation method

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0035] The method for synthesizing water-soluble silicon quantum dots by hydrothermal method with 3-aminopropyltrimethoxysilane as silicon source, its specific steps are as follows:

[0036] (1) Dissolve citric acid and sodium borohydride in deionized water under the protection of nitrogen, and then add 3-aminopropyltrimethoxysilane as a silicon source to control the silicon source: the molar ratio of citric acid: sodium borohydride = 1:0.2:0.2, wherein the concentration of 3-aminopropyltrimethoxysilane in water is 44mmol / L, the concentration of citric acid in water is 8.8mmol / L, and the concentration of sodium borohydride in water is 8.8mmol / L .

[0037] (2) Transfer the mixed solution into a high-pressure reactor and heat it to 140° C., and react for 3.5 hours to obtain a silicon quantum dot solution.

[0038] (3) Mix the prepared silicon quantum dot solution with methanol at a volume ratio of 1:3, centrifuge at 8000r / min for 10min, remove the supernatant, and freeze-dry th...

Embodiment 2

[0052] Using 3-aminopropyltrimethoxysilane as the method for silicon source hydrothermal synthesis of water-soluble silicon quantum dots, its preparation method is the same as in Example 1, the concentration of 3-aminopropyltrimethoxysilane in water is 44mmol / L , the difference lies in the different concentrations of the reducing agent citric acid and sodium borohydride. The molar ratio of 3-aminopropyltrimethoxysilane:citric acid:sodium borohydride is 1:0.2:0.2~1. After measurement, the fluorescence intensity of silicon quantum dots prepared under different ratios is shown in image 3 .

[0053] For each ratio, the quantum yield is shown in the table below:

[0054] Molar ratio of 3-aminopropyltrimethoxysilane:citric acid:sodium borohydride

1:0.2:0.2

1:0.2:0.4

1:0.2:0.6

1:0.2:0.8

1:0.2:1

quantum yield

32%

57%

67%

49%

45%

[0055] It has been determined that the quantum dots prepared in this embodiment have good pH stabilit...

Embodiment 3

[0058] The method for synthesizing water-soluble silicon quantum dots by hydrothermal method with 3-aminopropyltriethoxysilane as silicon source, its specific steps are as follows:

[0059] (1) Dissolve 3-aminopropyltriethoxysilane in deionized water under the protection of argon, the concentration of 3-aminopropyltrimethoxysilane in water is 44mmol / L, then add sodium borohydride and Sodium sulfite, control silicon source: sodium borohydride: sodium sulfite molar ratio=1:1:0.5.

[0060] (2) Transfer the stirred and evenly mixed solution into an autoclave and heat it to 170° C., and react for 2 hours to obtain a silicon quantum dot solution.

[0061] (3) Mix the obtained silicon quantum dot solution with ethanol evenly at the ratio of quantum dots:ethanol=1:2. Centrifuge at 8000r / min for 15min, remove the supernatant, and vacuum-dry the resulting precipitate to obtain solid silicon quantum dots.

[0062] The quantum yield of this embodiment is 50%.

[0063] It has been deter...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

PropertyMeasurementUnit
Particle sizeaaaaaaaaaa
Login to view more

Abstract

The invention discloses a water-phase preparation method of silicon quantum dots, comprising the following steps: (1) taking a reducing agent and a silane coupling agent and dissolving them in water under the protection of an inert gas, and the molar ratio of the silane coupling agent to the reducing agent is: 1:0.2~10; (2) Transfer the mixed solution obtained in step (1) into a high-pressure reactor and heat it to 140-220°C, and the silicon quantum dot solution can be obtained after the reaction; or the mixed solution obtained in step (1) The solution is transferred to a microwave reactor and heated to 140-220°C, and the silicon quantum dot solution can be obtained after the reaction; (3) the silicon quantum dot solution obtained in step (2) is mixed with an organic solvent, centrifuged, and the supernatant is removed. dry to obtain solid silicon quantum dots; wherein the reducing agent is citric acid, sodium sulfite, sodium borohydride, sodium citrate, ascorbic acid, urea, thiourea, hydrazine hydrate, L-cysteine, bovine serum albumin or Mixture of two or more in denatured bovine serum albumin.

Description

technical field [0001] The invention belongs to the technical field of preparation methods of nanomaterials, and specifically discloses a preparation method for water-phase synthesis of water-soluble fluorescent silicon quantum dots using a silane coupling agent as a silicon source and utilizing the synergistic effect of a reducing agent by using a hydrothermal method or a microwave method method. Background technique [0002] Quantum dots are quasi-zero-dimensional nanomaterials composed of II-VI or III-V elements with a diameter of 1 to 10 nm. Silicon is an indirect bandgap semiconductor. Traditional silicon nanomaterials emit very weak light, which limits their application in devices. However, when their size is continuously reduced, the quantum size effect enhances the fluorescence intensity of silicon quantum dots, exhibiting photophysical properties similar to those of direct bandgap semiconductors. In addition, compared with traditional II-VI or III-V quantum dots, ...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
IPC IPC(8): C09K11/59B82Y20/00B82Y40/00
CPCC09K11/59B82Y20/00B82Y40/00
Inventor 赵丹马诗瑶郝健
Owner SOUTH CENTRAL UNIVERSITY FOR NATIONALITIES
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products