High-specific capacitance low-impedance graphene/carbon nanotube composite material preparation method

A technology of carbon nanotubes and composite materials, which is applied in the field of preparation of high specific capacitance and low impedance graphene/carbon nanotube composite materials, which can solve the problems of low synthesis yield, complicated process and high cost

Inactive Publication Date: 2018-06-19
HUAQIAO UNIVERSITY
View PDF1 Cites 4 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0004] Although graphene / carbon nanotube composites have many excellent properties, the key to restricting their industrialization lies in the complex process, low synthesis yield, and high cost.

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
  • High-specific capacitance low-impedance graphene/carbon nanotube composite material preparation method
  • High-specific capacitance low-impedance graphene/carbon nanotube composite material preparation method
  • High-specific capacitance low-impedance graphene/carbon nanotube composite material preparation method

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0032] A preparation method of high specific capacitance and low impedance graphene / carbon nanotube composite material, comprising the steps of:

[0033] (1) Dissolve 0.03g graphene oxide in 18mL distilled water and sonicate for 30min to form a brown-yellow suspension;

[0034] (2) Use 5% sodium carbonate to adjust the pH of the suspension to 9-10, add sodium borohydride, sonicate for 10 minutes, stir magnetically at 80°C for 2 hours, and the mass ratio of graphene oxide to sodium borohydride is 1:8;

[0035] (3) Mix 75mL of concentrated sulfuric acid and 25mL of concentrated nitric acid; dissolve 0.2g of carbon nanotubes in the above mixed acid, ultrasonicate for 30min, filter, wash, freeze-dry, and fully grind for later use; weigh 0.004g of acidified carbon nanotubes Dissolve in 42mL distilled water and sonicate for 20min;

[0036] (4) Mix the material obtained in step (2) with the material obtained in step (3) and disperse uniformly by ultrasonic for 5 minutes, put it into...

Embodiment 2

[0041] The difference between this example and Example 1 is that the volume of the solvent for the hydrothermal reaction is changed to 50mL, and other conditions remain unchanged to obtain a graphene / carbon nanotube composite material. Please see Figure 5 , Test the specific capacitance of the present embodiment sample with electrochemical workstation (CHI660E), as shown in the figure, calculate with formula Cm=I Δt / m Δv, specific capacitance is 305F / g when 0.5A / g. Under the same current density, compared with the specific capacitance in Example 1, the analysis reason may be that an appropriate increase in the amount of solvent helps the uniform dispersion of graphene and carbon nanotubes, thereby improving the specific capacitance of the material.

Embodiment 3

[0043] The difference between this example and Example 1 is that the graphene / carbon nanotube composite material is obtained by changing the reduction temperature of graphene oxide in step (2) to 70° C. and keeping other conditions unchanged. Please see Image 6 , with the electrochemical workstation (CHI660E) to test the specific capacitance of the sample of this embodiment, as shown in the figure, calculated with the formula Cm=I Δt / m.Δv, the specific capacitance is 233.07F / g at 0.5A / g . Under the same current density, compared with the specific capacitance in Example 1, the analysis reason may be that the conductivity of graphene oxide is poor, and the conditions in Example 1 are more conducive to the reduction of graphene oxide, thereby improving the composite material. specific capacitance.

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
electrical resistanceaaaaaaaaaa
diameteraaaaaaaaaa
lengthaaaaaaaaaa
Login to view more

Abstract

The invention discloses a high-specific capacitance low-impedance graphene/carbon nanotube composite material preparation method. The method comprises the following steps: (1) graphene oxide is dissolved in a solvent for ultrasonic processing for 20 to 180 min, and a tan suspension with a concentration of 0.2 to 2 g/L is formed; (2) the above tan suspension and a reductant are mixed to be subjected to magnetic stirring for 1 to 6 h under 50 to 120 DEG C; (3) carbon nanotubes are dissolved in a mixed solution of concentrated sulfuric acid and concentrated nitric acid with a volume ratio of 2-4to 1 for ultrasonic processing for 20 to 180 min, and through sequentially filtering, washing, freezing and drying, the mixed solution is reserved; and (4) the material obtained in the second step andthe material obtained in the third step are mixed and are then subjected to ultrasonic dispersion uniformity, the mixture is then put to a closed reactor for reaction for 1 to 8 h under 150 to 300 DEG C, the mixture is then cooled to room temperature, and through sequentially filtering, washing, drying and grinding, a nano-scale graphene/carbon nanotube composite material is obtained. The specific capacitance value of the prepared graphene/carbon nanotube composite material can reach 200 to 800 F/g, and the charge transfer resistance is 5 to 100 omega.

Description

technical field [0001] The invention belongs to the technical field of graphene composite materials, in particular to a method for preparing a graphene / carbon nanotube composite material with high specific capacitance and low impedance. Background technique [0002] With the continuous development of social economy, the ecological environment and energy issues have attracted more and more attention. As a new type of energy storage device, supercapacitors are widely used by people due to their long service life, short charging time, energy saving and environmental protection. widespread attention. Graphene has a large specific surface area and good electrical conductivity, making it an ideal material for preparing supercapacitors. [0003] Graphene is a carbon atom with sp 2 The hexagonal honeycomb lattice composed of hybrid orbitals is a planar film. Carbon nanotubes have a special quasi-one-dimensional hollow tubular structure, in which carbon atoms are sp 2 hybridizati...

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): H01G11/24H01G11/32H01G11/36H01G11/44H01G11/86
CPCY02E60/13H01G11/24H01G11/32H01G11/36H01G11/44H01G11/86
Inventor 李东旭黄艳珍
Owner HUAQIAO UNIVERSITY
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

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap