Nanotechnology Now

Our NanoNews Digest Sponsors


Heifer International

Wikipedia Affiliate Button


DHgate

Home > Press > Creating nano-structures from the bottom up

This is a nano-structure.

Credit: Benjamin Yellen
This is a nano-structure.

Credit: Benjamin Yellen

Abstract:
Microscopic particles are being coaxed by Duke University engineers to assemble themselves into larger crystalline structures by the use of varying concentrations of microscopic particles and magnetic fields.

Creating nano-structures from the bottom up

Durham, NC | Posted on April 24th, 2012

These nano-scale crystal structures, which until now have been difficult and time-consuming to produce using current technologies, could be used as basic components for advanced optics, data storage and bioengineering, said the research team.

"Not only did we develop the theoretical underpinning for this new technique, but we demonstrated in the lab that we could create more than 20 different programmed structures," said Benjamin Yellen, assistant professor of mechanical engineering and materials science at Duke's Pratt School of Engineering and lead member of the research team. The results of the Duke experiments were published online in the journal Nature Communications.

"Despite the promise of creating new classes of man-made structures, current methods for creating these tiny structures in a reliable and cost-effective way remains a daunting challenge," Yellen said. "This new approach could open pathways for fabricating complex materials that cannot be produced by current techniques."

The research was supported by the Research Triangle Materials Research Science and Engineering Center, which is funded by the National Science Foundation.

The traditional method for creating man-made crystals is described as "top-down" by Yellen, which means they are fashioned by lithography or molding techniques, and can't be easily created in three dimensions.

"Our approach is much more 'bottom up,' in that we're starting at the level of a model 'atom' and working our way up," Yellen said.

By manipulating the magnetization within a liquid solution, the Duke researchers coaxed magnetic and non-magnetic particles to form intricate nano-structures, such as chains, rings and lattices.

The nano-structures are formed inside a liquid known as a ferrofluid, which is a solution consisting of suspensions of nanoparticles composed of iron-containing compounds. One of the unique properties of these fluids is that they become highly magnetized in the presence of external magnetic fields. The particles that are less magnetic than the ferrofluid behave similarly to negative charges, whereas the particles that are more magnetic than the ferrofluid act like positive charges. The opposite particles thus attract one another to form structures resembling salt crystals.

Since the magnetization of the fluid and the concentrations of the particles controls how the particles are attracted to or repelled by each other, the researchers were able to control the shapes and patterns of assembly. By appropriately "tuning" these interactions, the magnetic and non-magnetic particles form around each other much like a snowflake forms around a microscopic dust particle.

According to Yellen, researchers have long been able to create tiny structures made up of a single particle type, but the demonstration of sophisticated structures assembling in solutions containing multiple types of particles has been difficult to achieve. The structure of these nano-structures determines how they can ultimately be used.

Yellen foresees the use of these nano-structures in advanced optical devices, such as sensors, where different nano-structures could be designed to possess custom-made optical properties. Yellen also envisions that rings composed of metal particles could be used for antenna designs, and perhaps as one of the key components in the construction of materials that display artificial "optical magnetism" and negative magnetic permeability.

Other members of the team Duke's Karim Khalil, Amanda Sagategui, Mukarram Tahir, Joshua Socolar and Benjamin Wiley.

####

For more information, please click here

Contacts:
Richard Merritt

919-660-8414

Copyright © Duke University

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 Links

View video:

Related News Press

News and information

Light can 'heal' defects in new solar cell materials: Defects in some new electronic materials can be removed by making ions move under illumination May 24th, 2016

Attosecond physics: A switch for light-wave electronics May 24th, 2016

Supercrystals with new architecture can enhance drug synthesis May 24th, 2016

Nanoscale Trojan horses treat inflammation May 24th, 2016

Graphene: Progress, not quantum leaps May 23rd, 2016

Videos/Movies

Programmable materials find strength in molecular repetition May 23rd, 2016

Graphene makes rubber more rubbery May 23rd, 2016

ORNL demonstrates large-scale technique to produce quantum dots May 21st, 2016

Self Assembly

Searching for a nanotech self-organizing principle May 1st, 2016

Researchers create artificial protein to control assembly of buckyballs April 27th, 2016

Brookhaven's Oleg Gang Named a Battelle 'Inventor of the Year': Recognized for work using DNA to guide and regulate the self-assembly of nanoparticles into clusters and arrays with controllable properties April 25th, 2016

Researchers develop new semiconducting polymer for forthcoming flexible electronics April 21st, 2016

Sensors

Electronic device detects molecules linked to cancer, Alzheimer's and Parkinson's: An inexpensive portable biosensor has been developed by researchers at Brazil's National Nanotechnology Laboratory with FAPESP's support May 20th, 2016

Making organs transparent to improve nanomedicine (video) May 13th, 2016

Scientists take a major leap toward a 'perfect' quantum metamaterial: Berkeley Lab, UC Berkeley researchers lead study that uses trapped atoms in an artificial crystal of light May 13th, 2016

Quantum sensors for high-precision magnetometry of superconductors May 3rd, 2016

Discoveries

Light can 'heal' defects in new solar cell materials: Defects in some new electronic materials can be removed by making ions move under illumination May 24th, 2016

Attosecond physics: A switch for light-wave electronics May 24th, 2016

Supercrystals with new architecture can enhance drug synthesis May 24th, 2016

Nanoscale Trojan horses treat inflammation May 24th, 2016

Announcements

Light can 'heal' defects in new solar cell materials: Defects in some new electronic materials can be removed by making ions move under illumination May 24th, 2016

Attosecond physics: A switch for light-wave electronics May 24th, 2016

Supercrystals with new architecture can enhance drug synthesis May 24th, 2016

Nanoscale Trojan horses treat inflammation May 24th, 2016

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