Nanotechnology Now

Our NanoNews Digest Sponsors





Heifer International

Wikipedia Affiliate Button


DHgate

Home > Press > Crystal Defect Shown to be Key to Making Hollow Nanotubes

Spiraling pine tree-like nanowires created by University of Wisconsin-Madison chemistry professor Song Jin and graduate student Matthew Bierman are evidence of an entirely different way of growing the tiny wires, one that could be harnessed to make better nanowires for applications such as high performance integrated circuits, LEDs and lasers, biosensors, and solar cells. The rapid elongation of the trunks is driven by a spiral defect within them called "screw dislocation," which causes them to twist as they grow and their branches to spiral. Photo by: courtesy Song Jin
Spiraling pine tree-like nanowires created by University of Wisconsin-Madison chemistry professor Song Jin and graduate student Matthew Bierman are evidence of an entirely different way of growing the tiny wires, one that could be harnessed to make better nanowires for applications such as high performance integrated circuits, LEDs and lasers, biosensors, and solar cells. The rapid elongation of the trunks is driven by a spiral defect within them called "screw dislocation," which causes them to twist as they grow and their branches to spiral. Photo by: courtesy Song Jin

Abstract:
Scientists have no problem making a menagerie of nanometer-sized objects - wires, tubes, belts, and even tree-like structures. What they sometimes have been unable to do is explain precisely how those objects form in the vapor and liquid cauldrons in which they are made.

Crystal Defect Shown to be Key to Making Hollow Nanotubes

Madison, WI | Posted on April 24th, 2010

Now a team led by University of Wisconsin-Madison chemist Song Jin, writing this week (April 23, 2010) in the journal Science, shows that a simple crystal defect known as a "screw dislocation" drives the growth of hollow zinc oxide nanotubes just a few millionths of a centimeter thick.

The finding is important because it provides new insight into the processes that guide the formation of the smallest manufactured structures, a significant challenge in nanoscience and nanotechnology. "We think that this work provides a general theoretical framework for controlling nanowire or nanotube growth without using metal catalysts that can be generally applicable to many materials," says Jin, a UW-Madison professor of chemistry.

Such materials and the Lilliputian structures scientists sculpt have already found broad applications in such things as electronics, solar power, battery and laser technology, and chemical and biological sensing. By further expanding the theory of how the tiny structures form, it should now be possible for scientists to develop new methods to mass produce nano-sized objects using a variety of different materials.

The method described by Jin and his colleagues depends on what scientists call a screw dislocation. Dislocations are fundamental to the growth and characteristics of all crystalline materials. As their name implies, these defects prompt the creation of spiral steps on an otherwise flawless crystal face. As atoms alight on the crystal surface, they form a structure strikingly similar in appearance to the spiral ramps of multistory parking structures. In earlier work, Jin and his research group showed that screw dislocations drive the growth of one-dimensional nanowire structures that looked like tiny pine trees. That, says Jin, was a critical clue to understanding the kinetics of spontaneous nanotube growth.

The key to understanding how to harness the defect to make nanostructures in a rational way, Jin explains, is knowing that as atoms collect on a surface of a dislocation spiral, strain associated with screw dislocations builds up in the tiny structures they create.

It turns out that "making the structure hollow and making it twist are two good ways of relieving such strain and stress," Jin explains. "In some cases, the large screw dislocation strain energy contained within the nanomaterial dictates that the material hollow out its center around the dislocation, thus resulting in the spontaneous formation of nanotubes."

The phenomenon described in the new Wisconsin work differs in significant ways from traditional mechanisms of making hollow nanostructures. Scientists now use templates to "mold" nanotubes or, alternatively, a diffusion process to convert one material into another with a hollow core. Carbon nanotubes are made, essentially, by rolling up a single honeycomb-patterned layer of carbon atoms.

The phenomena described by the Wisconsin team, Jin adds, should apply to materials beyond zinc oxide: "The understanding of the formation of nanotubes will certainly help us to understand related phenomena in other materials."

Refined, the new knowledge could ultimately be turned to the large scale, low cost production of nanomaterials for a wide range of applications. Most promising, says Jin, is the area of renewable energy where large amounts of such materials can be deployed to convert sunlight to electricity, and provide new raw materials for battery electrodes and thermoelectric devices.

The new work in Jin's lab was carried out by graduate students Stephen A. Morin and Matthew J. Bierman, with assistance from a former undergraduate student Jonathan Tong, all of UW-Madison. The work was funded primarily by National Science Foundation.

####

For more information, please click here

Contacts:
Terry Devitt
(608) 262-8282

Copyright © University of Wisconsin-Madison

If you have a comment, please Contact us.

Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

Bookmark:
Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related News Press

News and information

Quantum states in a nano-object manipulated using a mechanical system August 3rd, 2015

Nanoparticles used to breach mucus barrier in lungs: Proof-of-concept study conducted in mice a key step toward better treatments for lung diseases August 3rd, 2015

Promising Step Taken in Iran towards Treatment of Spinal Cord Injury August 3rd, 2015

Diagnosis of Salmonella Bacterium-Caused Food Poisoning by Biosensors August 3rd, 2015

Chemistry

March 2016; 6th Int'l Conference on Nanostructures in Iran July 29th, 2015

Meet the high-performance single-molecule diode: Major milestone in molecular electronics scored by Berkeley Lab and Columbia University team July 29th, 2015

'Seeing' molecular interactions could give boost to organic electronics July 28th, 2015

Quantum networks: Back and forth are not equal distances! July 28th, 2015

Govt.-Legislation/Regulation/Funding/Policy

Small tilt in magnets makes them viable memory chips August 3rd, 2015

Vaccine with virus-like nanoparticles effective treatment for RSV, study finds August 3rd, 2015

MIPT researchers clear the way for fast plasmonic chips August 3rd, 2015

Nanoparticles used to breach mucus barrier in lungs: Proof-of-concept study conducted in mice a key step toward better treatments for lung diseases August 3rd, 2015

Possible Futures

Nanofiltration Membrane Market 2015 - Global Industry Survey, Analysis, Size, Share, Outlook and Forecast to 2020 July 31st, 2015

Nanozirconia Market 2015 - Global Industry Survey, Analysis, Size, Share, Outlook and Forecast to 2020 July 31st, 2015

Self-Healing Nano Anti-rust Coatings Market 2015 - Global Industry Survey, Analysis, Size, Share, Outlook and Forecast to 2020 July 31st, 2015

Nano Spray Instrument Market 2015 - Global Industry Survey, Analysis, Size, Share, Outlook and Forecast to 2020 July 31st, 2015

Nanotubes/Buckyballs/Fullerenes

Better together: Graphene-nanotube hybrid switches August 3rd, 2015

Self-assembling, biomimetic membranes may aid water filtration August 1st, 2015

Controlling Dynamic Behavior of Carbon Nanosheets in Structures Made Possible July 30th, 2015

March 2016; 6th Int'l Conference on Nanostructures in Iran July 29th, 2015

Announcements

Quantum states in a nano-object manipulated using a mechanical system August 3rd, 2015

Nanoparticles used to breach mucus barrier in lungs: Proof-of-concept study conducted in mice a key step toward better treatments for lung diseases August 3rd, 2015

Promising Step Taken in Iran towards Treatment of Spinal Cord Injury August 3rd, 2015

Diagnosis of Salmonella Bacterium-Caused Food Poisoning by Biosensors August 3rd, 2015

Energy

Transparent, electrically conductive network of encapsulated silver nanowires: A novel electrode for optoelectronics August 1st, 2015

Springer and Tsinghua University Press present the second Nano Research Award: Paul Alivisatos of the University of California Berkeley receives the honor for outstanding contributions in nanoscience July 30th, 2015

Controlling Dynamic Behavior of Carbon Nanosheets in Structures Made Possible July 30th, 2015

March 2016; 6th Int'l Conference on Nanostructures in Iran July 29th, 2015

Solar/Photovoltaic

Transparent, electrically conductive network of encapsulated silver nanowires: A novel electrode for optoelectronics August 1st, 2015

Springer and Tsinghua University Press present the second Nano Research Award: Paul Alivisatos of the University of California Berkeley receives the honor for outstanding contributions in nanoscience July 30th, 2015

Reshaping the solar spectrum to turn light to electricity: UC Riverside researchers find a way to use the infrared region of the sun's spectrum to make solar cells more efficient July 27th, 2015

Rice University finding could lead to cheap, efficient metal-based solar cells: Plasmonics study suggests how to maximize production of 'hot electrons' July 22nd, 2015

NanoNews-Digest
The latest news from around the world, FREE



  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoTech-Transfer
University Technology Transfer & Patents
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More











ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project