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

Small but heading for the big time: Nanobiotix half year results for the six months ended 30 June 2015, in line with expectations: Major clinical achievements and corporate developments August 28th, 2015

A new technique to make drugs more soluble August 28th, 2015

Nanocatalysts improve processes for the petrochemical industry August 28th, 2015

Nanolab Technologies LEAPS Forward with High-Performance Analysis Services to the World: Nanolab Orders Advanced Local Electrode Atom Probe (LEAP®) Microscope from CAMECA Unit of AMETEK Materials Analysis Division August 27th, 2015

Chemistry

A new technique to make drugs more soluble August 28th, 2015

Nanocatalysts improve processes for the petrochemical industry August 28th, 2015

Govt.-Legislation/Regulation/Funding/Policy

These microscopic fish are 3-D-printed to do more than swim: Researchers demonstrate a novel method to build microscopic robots with complex shapes and functionalities August 26th, 2015

Glitter from silver lights up Alzheimer's dark secrets August 25th, 2015

Southampton scientists find new way to detect ortho-para conversion in water August 25th, 2015

Industrial Nanotech, Inc. Provides Update On Hospital Project, PCAOB Audit, and New Heat Shield™ Line August 24th, 2015

Possible Futures

Sediment dwelling creatures at risk from nanoparticles in common household products August 13th, 2015

Harris & Harris Group Reports Financial Statements as of June 30, 2015, and Announces a Stock Repurchase Program August 10th, 2015

Molecular trick alters rules of attraction for non-magnetic metals August 5th, 2015

Global Carbon Nanotubes Industry 2015: Acute Market Reports August 4th, 2015

Nanotubes/Buckyballs/Fullerenes

Developing Component Scale Composites Using Nanocarbons August 26th, 2015

Southampton scientists find new way to detect ortho-para conversion in water August 25th, 2015

Revolutionary MIT-Developed Nanotechnology Company Showcases at CAMX in Dallas August 20th, 2015

Engineering a better 'Do: Purdue researchers are learning how August 4th, 2015

Announcements

Small but heading for the big time: Nanobiotix half year results for the six months ended 30 June 2015, in line with expectations: Major clinical achievements and corporate developments August 28th, 2015

A new technique to make drugs more soluble August 28th, 2015

Nanocatalysts improve processes for the petrochemical industry August 28th, 2015

Nanolab Technologies LEAPS Forward with High-Performance Analysis Services to the World: Nanolab Orders Advanced Local Electrode Atom Probe (LEAP®) Microscope from CAMECA Unit of AMETEK Materials Analysis Division August 27th, 2015

Energy

Nanocatalysts improve processes for the petrochemical industry August 28th, 2015

Nanotechnology that will impact the Security & Defense sectors to be discussed at NanoSD2015 conference August 25th, 2015

Industrial Nanotech, Inc. Provides Update On Hospital Project, PCAOB Audit, and New Heat Shield™ Line August 24th, 2015

Novel nanostructures for efficient long-range energy transport August 21st, 2015

Solar/Photovoltaic

CWRU researchers efficiently charge a lithium-ion battery with solar cell: Coupling with perovskite solar cell holds potential for cleaner cars and more August 27th, 2015

Novel nanostructures for efficient long-range energy transport August 21st, 2015

Charge transport in hybrid silicon solar cells August 17th, 2015

Nano Electrolyte Additives Increase Efficiency of Solar Cells August 10th, 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







Car Brands
Buy website traffic