Blue-light and green-light lignin carbon quantum dots with high quantum yield as well as preparation method and application thereof

A plain carbon quantum and high quantum technology, which is applied in the field of lignin carbon quantum dots and its preparation, can solve the problems of harsh preparation conditions and low quantum yield, and achieve the effect of low price, wide sources, and improved quantum yield

Active Publication Date: 2021-06-25
GUANGDONG UNIV OF TECH
View PDF5 Cites 6 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0007] In order to overcome the disadvantages and deficiencies of the harsh preparation conditions of lignin carbon quantum dots in the prior art, only emitting blue or only green light and low quantum yield, The primary purpose of the present invention is to provide a preparation method of blue light and green light lignin carbon quantum dots with high quantum yield

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
  • Blue-light and green-light lignin carbon quantum dots with high quantum yield as well as preparation method and application thereof
  • Blue-light and green-light lignin carbon quantum dots with high quantum yield as well as preparation method and application thereof

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0035] Weigh 0.05g of modified lignin and 7.6852g of citric acid, disperse in 25ml of ultrapure water under magnetic stirring, add 1g of ethylenediamine, disperse with ultrasonic oscillation for 20min; , after natural cooling to room temperature, the crude lignin carbon quantum dot product was obtained; the crude product was centrifuged, the obtained supernatant was separated with a 0.22 μm filter membrane, and the filtrate was collected; Plain carbon quantum dot solution, its quantum yield is measured to be 43.26%. The lignin carbon quantum dot solution is rotatively evaporated at 30° C., and then freeze-dried to obtain the lignin carbon quantum dot solid powder.

[0036] The electron microscope picture (inset is the corresponding high-resolution TEM picture) of the lignin carbon quantum dot obtained in the present embodiment is as follows figure 1 As shown, transmission electron microscope observation shows that lignin carbon quantum dots are well dispersed, almost spherica...

Embodiment 2

[0039] Weigh 1g of modified lignin and 3.8426g of citric acid, disperse in 50ml of ultrapure water under magnetic stirring, add 0.5g of o-phenylenediamine, disperse with ultrasonic oscillation for 5min; Take it out, cool it down to room temperature naturally, and get the crude product of lignin carbon quantum dots; centrifuge the crude product, separate the obtained supernatant with a 0.22 μm membrane filter, and collect the filtrate; after the filtrate is dialyzed and purified with a 3500Da specification dialysis bag, you can get The lignin carbon quantum dot solution has a measured quantum yield of 53.46%. The lignin carbon quantum dot solution is rotatively evaporated at 50° C., and then freeze-dried to obtain the lignin carbon quantum dot solid powder.

Embodiment 3

[0041] Weigh 0.5g of modified lignin and 11.5278g of citric acid, disperse in 30ml of ultrapure water under magnetic stirring, add 1g of urea, disperse with ultrasonic oscillation for 30min; After cooling to room temperature, the crude lignin carbon quantum dot product is obtained; the crude product is centrifuged, the obtained supernatant is separated with a 0.22 μm filter membrane, and the filtrate is collected; the filtrate is dialyzed and purified with a 1000Da dialysis bag to obtain lignin carbon The quantum dot solution has a measured quantum yield of 43.46%. The lignin carbon quantum dot solution is rotatively evaporated at 70° C., and then freeze-dried to obtain the lignin carbon quantum dot solid powder.

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 belongs to the field of biomass fluorescent nano materials, and particularly relates to a blue-light and green-light lignin carbon quantum dot with high quantum yield as well as a preparation method and application thereof. According to the method, modified lignin and citric acid are subjected to dehydration, polymerization and carbonization to form lignin carbon quantum dots, and the lignin carbon quantum dots are protonated or deprotonated by adjusting the pH value, so that the fluorescent carbon quantum dots emitting blue and green light are obtained. The non-radiative transition process is reduced through heteroatom doping, so that the lignin carbon quantum dots with high quantum yield are obtained, and the absolute quantum yield can reach 59.3% at most. Compared with other non-biomass precursors such as polycyclic aromatic hydrocarbon, lignin is renewable, wide in source, low in price, non-toxic and harmless; Compared with other biomass-based compounds such as cellulose, hemicellulose and lignin, the carbon content is higher, and the biomass-based compound is the only natural polymer containing a large number of conjugated aromatic structures in nature, so that the carbon quantum dots are easier to obtain theoretically.

Description

technical field [0001] The invention belongs to the field of biomass fluorescent nanomaterials, in particular to a blue-light and green-light lignin carbon quantum dot with high quantum yield and its preparation method and application. Background technique [0002] Due to its unique structure, carbon quantum dots have many excellent properties, and the most common application is fluorescence properties. At present, there are two main explanations for the fluorescence emission mechanism of carbon quantum dots: the first is considered to be the fluorescence emission caused by different surface defects of carbon quantum dots; the other is the quantum confinement effect, and the difference in particle size is caused by different fluorescent colors. s reason. The in-depth study of the fluorescence emission mechanism is of great significance to the efficient preparation and application of carbon quantum dots. [0003] Since carbon quantum dots have a graphite-like lattice struct...

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
Patent Type & Authority Applications(China)
IPC IPC(8): C09K11/65B82Y20/00B82Y40/00B82Y30/00
CPCC09K11/65B82Y20/00B82Y40/00B82Y30/00
Inventor 秦延林袁慢景徐少杰胡玉彬林绪亮李宇亮张文礼王铁军
Owner GUANGDONG UNIV OF TECH
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