Research & Development World

  • R&D World Home
  • Topics
    • Aerospace
    • Automotive
    • Biotech
    • Careers
    • Chemistry
    • Environment
    • Energy
    • Life Science
    • Material Science
    • R&D Management
    • Physics
  • Technology
    • 3D Printing
    • A.I./Robotics
    • Software
    • Battery Technology
    • Controlled Environments
      • Cleanrooms
      • Graphene
      • Lasers
      • Regulations/Standards
      • Sensors
    • Imaging
    • Nanotechnology
    • Scientific Computing
      • Big Data
      • HPC/Supercomputing
      • Informatics
      • Security
    • Semiconductors
  • R&D Market Pulse
  • R&D 100
    • Call for Nominations: The 2025 R&D 100 Awards
    • R&D 100 Awards Event
    • R&D 100 Submissions
    • Winner Archive
    • Explore the 2024 R&D 100 award winners and finalists
  • Resources
    • Research Reports
    • Digital Issues
    • R&D Index
    • Subscribe
    • Video
    • Webinars
  • Global Funding Forecast
  • Top Labs
  • Advertise
  • SUBSCRIBE

Nanotubes with two walls have singular qualities

By R&D Editors | April 15, 2015

Researchers at Rice Univ. are working to determine the electronic properties of double-walled carbon nanotubes. In this example, the team analyzed a nanotube with two zigzag components. The individual nanotubes have band gaps and are semiconductors, but when combined, the band gaps overlap and make the double-walled a semimetal. Image: Matías Soto Rice Univ. researchers have determined that two walls are better than one when turning carbon nanotubes into materials like strong, conductive fibers or transistors.

Rice materials scientist Enrique Barrera and his colleagues used atomic-level models of double-walled nanotubes to see how they might be tuned for applications that require particular properties. They knew from others’ work that double-walled nanotubes are stronger and stiffer than their single-walled cousins. But they found it may someday be possible to tune double-walled tubes for specific electronic properties by controlling their configuration, chiral angles and the distance between the walls.

The research was reported in Nanotechnology.

Carbon nanotubes, grown by various methods, come in two basic varieties: single-walled and multi-walled (those with two or more walls). But double-walled tubes hold a special place in the hierarchy because, the researchers wrote, they behave somewhat like single-walled tubes but are stronger and better able to survive extreme conditions.

The Rice team found there’s even more to them when they started looking at how the inner and outer walls match up using tubes with zigzag chirality. Because the electrical properties of single-walled tubes depend on their chirality—the angles of their hexagonal arrangement of atoms—the researchers thought it would be interesting to learn more about those properties in double-walled tubes.

“We saw that the interwall interaction could affect the electronic properties of double-walled carbon nanotubes and decided to study this effect in a more systematic way using computational simulations,” Soto said.

It turned out that both the distance between the walls—as small as a fraction of a nanometer—and the individual chirality of the tubes impact the double-walls’ electrical properties. In addition, the researchers found the diameter of the tube—especially the inner one, with its more pronounced curvature—has a small but significant impact on the structure’s semiconducting properties.

Breaking it down further, they determined that semiconducting nanotubes wrapped around metallic, highly conductive nanotubes could be the best candidates for tuning the band gap, the property that defines the value of a semiconductor.

“The most interesting thing we found was that when you combine a metallic with a semiconductor, the band gap depends on the distance between them,” Soto said.

It’s not yet possible to do so, but the ability to adjust the distance between walls may lead to nanotube transistors, he said.

Other nanotube configurations may be best for turning into macroscopic carbon nanotube conducting wires, particularly with metallic-metallic nanotubes, the researchers found.

Source: Rice Univ.

ENTRIES OPEN:
Establish your company as a technology leader. For 50 years, the R&D 100 Awards, widely recognized as the “Oscars of Invention,” have showcased products of technological significance. Learn more.

Related Articles Read More >

KIST carbon nanotube supercapacitor holds capacity after 100,000 cycles
A new wave of metalworking lets semiconductor crystals bend and stretch
LLNL deposits quantum dots on corrugated IR chips in a single step
KATRIN inauguration photo form 2018
Neutrinos pinned below 0.45 eV; KATRIN halves the particle’s mass ceiling
rd newsletter
EXPAND YOUR KNOWLEDGE AND STAY CONNECTED
Get the latest info on technologies, trends, and strategies in Research & Development.
RD 25 Power Index

R&D World Digital Issues

Fall 2024 issue

Browse the most current issue of R&D World and back issues in an easy to use high quality format. Clip, share and download with the leading R&D magazine today.

Research & Development World
  • Subscribe to R&D World Magazine
  • Enews Sign Up
  • Contact Us
  • About Us
  • Drug Discovery & Development
  • Pharmaceutical Processing
  • Global Funding Forecast

Copyright © 2025 WTWH Media LLC. All Rights Reserved. The material on this site may not be reproduced, distributed, transmitted, cached or otherwise used, except with the prior written permission of WTWH Media
Privacy Policy | Advertising | About Us

Search R&D World

  • R&D World Home
  • Topics
    • Aerospace
    • Automotive
    • Biotech
    • Careers
    • Chemistry
    • Environment
    • Energy
    • Life Science
    • Material Science
    • R&D Management
    • Physics
  • Technology
    • 3D Printing
    • A.I./Robotics
    • Software
    • Battery Technology
    • Controlled Environments
      • Cleanrooms
      • Graphene
      • Lasers
      • Regulations/Standards
      • Sensors
    • Imaging
    • Nanotechnology
    • Scientific Computing
      • Big Data
      • HPC/Supercomputing
      • Informatics
      • Security
    • Semiconductors
  • R&D Market Pulse
  • R&D 100
    • Call for Nominations: The 2025 R&D 100 Awards
    • R&D 100 Awards Event
    • R&D 100 Submissions
    • Winner Archive
    • Explore the 2024 R&D 100 award winners and finalists
  • Resources
    • Research Reports
    • Digital Issues
    • R&D Index
    • Subscribe
    • Video
    • Webinars
  • Global Funding Forecast
  • Top Labs
  • Advertise
  • SUBSCRIBE