Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Synthesis of ferromagnetic carbon nanometer tube

A technology of carbon nanotubes and synthesis methods, applied in nanotechnology, nanotechnology, nanostructure manufacturing, etc.

Inactive Publication Date: 2005-05-11
NANJING UNIV
View PDF0 Cites 4 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

So far, some organic ferromagnets with high Tc have been found, such as: highly oriented cracked graphite, graphite in meteorites, graphite irradiated by protons, C 60 Oxidation products, amorphous carbon, and carbon foams, among others, these findings challenge the understanding of ferromagnetism in carbon-based materials

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
  • Synthesis of ferromagnetic carbon nanometer tube
  • Synthesis of ferromagnetic carbon nanometer tube
  • Synthesis of ferromagnetic carbon nanometer tube

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0028] Put the porcelain boat loaded with 1g Zn powder into the quartz tube as the catalyst, and take another clean porcelain boat as the substrate, the distance between the two is 2cm. Introduce Ar gas (60sccm), at 10°C min -1 The rate starts to heat up, and when it reaches 460 °C, H 2 (20sccm), pass C at 500℃ 2 h 2 (20sccm); continue to heat up to 800°C, and keep at this temperature for 30min; finally at 8°Cmin -1 rate down to room temperature.

[0029] The product on the substrate was collected and split in two, one was treated with ultrapure concentrated HCl and the other was not. The content of metal impurities in the two samples was determined by ICP method, and their magnetic properties were tested on the SQUID instrument. The morphology and structure were observed by transmission electron microscope ( figure 1 ). M-T curve ( Figure 6a ) shows that there are two ferromagnetic phases with long-range order (Tc is about 500K and above 800K); the M-H curve ( Figu...

Embodiment 2

[0031] Put the porcelain boat loaded with 1g Zn powder into the quartz tube as a catalyst; take another clean porcelain boat as the substrate, and the distance between the two is 2cm. Introduce Ar gas (60sccm), at 10°C min -1 The temperature is raised at a rate of 500°C, and C 2 h 2 (20sccm); continue to heat up to 800°C, and keep at this temperature for 30min; stop feeding acetylene, then at 8°Cmin -1 rate down to room temperature.

[0032] Collect the products on the substrate, use SEM and TEM to observe its morphology and structure, then wrap it with 99.99% aluminum foil, and use SQUID to test its magnetic properties. TEM reveals having the same figure 1 Similar morphology and structure, M-H curve shows the existence of hysteresis loop, Ms is 0.22emu g -1 (300K), Hc is 145Oe (300K).

Embodiment 3

[0034] Put the porcelain boat loaded with 1g Zn powder into the quartz tube as the catalyst; take another clean quartz plate as the substrate, and the distance between the two is 4cm. Then pass Ar gas (60sccm) at 14°C min -1 The temperature is raised at a rate of 460 ° C, and H is introduced 2 (20sccm), switch the carrier flow to CH at 500°C 3 CH 2 OH vapor saturator, bubbled through CH 3 CH 2 After OH and Zn vapor are mixed, enter the reaction zone, continue to heat up to 850 ° C, and keep at this temperature for 30 minutes, stop feeding CH 3 CH 2 OH vapor, then at 10°C min -1 rate down to room temperature.

[0035] The product on the substrate was collected and treated with ultrapure concentrated HCl, and the yield was significantly reduced compared to Example 1. TEM reveals having the same figure 1 Similar morphology and structure, using VSM to test its magnetic properties, the M-H curve shows that there is hysteresis, and the Ms is 0.385emu g -1 (300K), Hc is 167...

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
Curie pointaaaaaaaaaa
Login to View More

Abstract

Synthesis of ferromagnetic carbon nanometer tube is disclosed. It includes 1) putting porcelain boat, quartz or single-crystal silicon slice into quartz tube as substrate and putting another porcelain boat with zinc powder into quartz tube as catalytic source; 2) inducing insert gas, inducing hydrogen at 450-550deg.C, inducing carbon source at 500-600deg.C, heating to 750-1000deg.C, and keeping temperature for 15-50 mins; 3) shutting carbon source, shutting hydrogen and insert gas until to room temperature, and collecting products on substrate. It achieves good stability and repeatability.

Description

1. Technical field [0001] The invention relates to a method for synthesizing ferromagnetic carbon nanotubes under the action of a nonmagnetic metal catalyst. 2. Background technology [0002] Scientists generally believe that only materials composed of elements containing 3d and 4f electrons can have long-range ordered ferromagnetic phases. There are doubts about whether pure organic materials can become ferromagnets, but organic ferromagnets have outstanding properties such as light weight. Advantages, therefore, the search for organic ferromagnets has not ceased. Since 1990, some organic ferromagnets have been discovered one after another, but due to reasons such as weak magnetism and low ferromagnetic transition temperature (Tc), they did not attract enough attention from the academic community until Makarova and his collaborators discovered the rhombohedral structure in 2001. C 60 The polymer has ferromagnetism and its Tc is as high as 500K, which has sparked a new rou...

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): B82B3/00C01B31/00
Inventor 徐正韩敏
Owner NANJING UNIV
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products

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

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com