Nanotechnology Now







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

Videos/Movies

Los Alamos Develops New Technique for Growing High-Efficiency Perovskite Solar Cells: Researchersí crystal-production insights resolve manufacturing difficulty January 29th, 2015

News and information

Advantest to Exhibit at SEMICON Korea in Seoul, South Korea February 4-6 Showcasing Broad Portfolio of Semiconductor Products, Technologies and Solutions January 29th, 2015

Park Systems Announces Innovations in Bio Cell Analysis with the Launch of Park NX-Bio, the only 3-in-1 Imaging Nanoscale Tool Available for Life Science Researchers January 29th, 2015

2015 Nanonics Image Contest January 29th, 2015

Iranian Scientists Use MOFs to Eliminate Dye Pollutants January 29th, 2015

Self Assembly

Engineering self-assembling amyloid fibers January 26th, 2015

Revealed: How bacteria drill into our cells and kill them December 2nd, 2014

Live Images from the Nano-cosmos: Researchers watch layers of football molecules grow November 5th, 2014

Outsmarting Thermodynamics in Self-assembly of Nanostructures: Berkeley Lab reports method for symmetry-breaking in feedback-driven self-assembly of optical metamaterials November 4th, 2014

Sensors

Detection of Heavy Metals in Samples with Naked Eye January 26th, 2015

GS7 Graphene Sensor maybe Solution in Fight Against Cancer January 25th, 2015

Nanosensor Used for Simultaneous Determination of Effective Tea Components January 24th, 2015

Iranian Scientists Produce Graphene-Based Oxygen Sensor January 23rd, 2015

Discoveries

Creating new materials with quantum effects for electronics January 29th, 2015

Los Alamos Develops New Technique for Growing High-Efficiency Perovskite Solar Cells: Researchersí crystal-production insights resolve manufacturing difficulty January 29th, 2015

Iranian Scientists Use MOFs to Eliminate Dye Pollutants January 29th, 2015

Made-in-Singapore rapid test kit detects dengue antibodies from saliva: IBN's MedTech innovation simplifies diagnosis of infectious diseases January 29th, 2015

Announcements

Advantest to Exhibit at SEMICON Korea in Seoul, South Korea February 4-6 Showcasing Broad Portfolio of Semiconductor Products, Technologies and Solutions January 29th, 2015

Park Systems Announces Innovations in Bio Cell Analysis with the Launch of Park NX-Bio, the only 3-in-1 Imaging Nanoscale Tool Available for Life Science Researchers January 29th, 2015

2015 Nanonics Image Contest January 29th, 2015

Iranian Scientists Use MOFs to Eliminate Dye Pollutants January 29th, 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







© Copyright 1999-2015 7th Wave, Inc. All Rights Reserved PRIVACY POLICY :: CONTACT US :: STATS :: SITE MAP :: ADVERTISE