Hollow bowl-shaped nitrogen-doped cobalt/carbon composite material, preparation method and application

A technology of carbon composite materials and hollow bowls, applied in chemical instruments and methods, and other chemical processes, to achieve the effects of expanding the wave-absorbing frequency band, increasing electronic polarization, and improving conductivity

Active Publication Date: 2021-12-14
NORTHWESTERN POLYTECHNICAL UNIV +1
View PDF0 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, there are very few studies on the hollow bowl-shaped magnetic porous composites in the field of electromagnetic wave absorption.

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
  • Hollow bowl-shaped nitrogen-doped cobalt/carbon composite material, preparation method and application
  • Hollow bowl-shaped nitrogen-doped cobalt/carbon composite material, preparation method and application
  • Hollow bowl-shaped nitrogen-doped cobalt/carbon composite material, preparation method and application

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0038] A kind of preparation method of hollow bowl-shaped nitrogen-doped cobalt / carbon composite material, see figure 1 shown, including the following steps:

[0039] Preparation of hollow bowl-shaped sulfonated polystyrene microspheres (SPS)

[0040] Take an appropriate amount of hollow polystyrene microsphere suspension and place it in an open beaker, and place it in the air. Using the difference between the capillary force generated by the solvent volatilization and the internal and external stress, the surface of the polystyrene microsphere is gradually depressed into a bowl shape. After the solvent is all volatilized, white hollow bowl-shaped polystyrene microspheres are formed; the polystyrene microspheres and concentrated sulfuric acid with a mass ratio of 1:17 are placed in a round-bottomed flask, placed on a magnetic stirrer, and the set temperature is 40°C, the rotation speed is 900 rpm, the purpose is to sulfonate polystyrene microspheres, react for half an hour, c...

Embodiment 2

[0048] Same as Example 1, the difference is:

[0049] Preparation of hollow bowl-shaped nitrogen-doped cobalt / carbon composites

[0050] Take 0.5 g of the above-prepared precursor and place it in a muffle furnace, blow nitrogen into it, set the heating rate at 2°C per minute, keep it at 800°C for two hours, and then drop it to 400°C at a cooling rate of 5°C per minute After cooling down to room temperature naturally, a hollow bowl-shaped nitrogen-doped cobalt / carbon composite material (HBN-Co / C-800) is obtained.

Embodiment 3

[0052] Same as Example 1, the difference is:

[0053] Preparation of hollow bowl-shaped nitrogen-doped cobalt / carbon composites

[0054] Take 0.5 g of the above-prepared precursor and place it in a muffle furnace, blow nitrogen into it, set the heating rate at 2°C per minute, keep it at 900°C for two hours, and then drop it to 400°C at a cooling rate of 5°C per minute After cooling down to room temperature naturally, a hollow bowl-shaped nitrogen-doped cobalt / carbon composite material (HBN-Co / C-900) is obtained.

[0055] In order to illustrate the properties of the hollow bowl-shaped nitrogen-doped cobalt / carbon composite material prepared by the preparation method provided by the present invention, X-ray Diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Raman (Raman), specific surface area (BET), electromagnetic wave absorption performance and other instruments for testing and characterization, see Figure 2-6 .

[0056] When testing the electromagnetic parameters...

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 diameteraaaaaaaaaa
absorption bandwidthaaaaaaaaaa
absorption bandwidthaaaaaaaaaa
Login to view more

Abstract

The invention discloses a method for preparing a hollow bowl-shaped nitrogen-doped cobalt / carbon composite material, and relates to the technical field of electromagnetic absorption materials. The method comprises the following steps: providing hollow bowl-shaped sulfonated polystyrene microspheres; preparing cobalt salt methanol solution, the concentration of the cobalt salt methanol solution being 2-4 g / L; using hollow bowl-shaped sulfonated polystyrene microspheres and 2‑ Methylimidazole is used as a raw material, anhydrous methanol is used as a reaction solvent, and the cobalt salt methanol solution is added to the reaction solution at 65-80° C., and the reaction is continued for 0.5-1.5 hours to obtain a precursor; in a nitrogen atmosphere, the The obtained precursor is kept at 700-900° C. for 1.5-3 hours, and then cooled to obtain the composite material. The hollow bowl-shaped structure transition metal (Co) doped (N) hierarchical porous structure carbon composite material provided by the present invention utilizes the composition and microstructure adjustable properties of MOFs to adjust the dielectric constant of the composite material to the low frequency range, and at the same time the special The hollow bowl-shaped configuration strengthens multiple losses, expands the absorbing frequency band, and realizes broadband absorption of absorbing materials under a thin layer.

Description

technical field [0001] The invention relates to the technical field of electromagnetic absorption materials, in particular to a hollow bowl-shaped nitrogen-doped cobalt / carbon composite material, a preparation method and an application. Background technique [0002] Magnetoelectric recombination loss is one of the main loss mechanisms of electromagnetic waves in matter, which combines many loss characteristics of magnetic loss and electrical loss, such as resistive loss, hysteresis loss and damping loss. Usually, the magnetic loss absorbing materials are mostly ferromagnetic materials, including Co, Zn-based ferrite and their doping systems, etc. Electric loss absorbing materials are divided into resistive loss absorbing materials and dielectric loss absorbing materials, including carbon-based materials (graphite, carbon nanotubes, etc.), conductive polymers, and plasma materials. Ferromagnetic materials and carbon-based materials can be combined to form magnetoelectric com...

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 Patents(China)
IPC IPC(8): C09K3/00
CPCC09K3/00
Inventor 梁瑾孔杰周琳龚建刚赵金凤
Owner NORTHWESTERN POLYTECHNICAL UNIV
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