Featured Research

from universities, journals, and other organizations

Diamond plates create nanostructures through pressure, not chemistry

Date:
June 27, 2014
Source:
Sandia National Laboratories
Summary:
Mechanical force -- about the same that raises the numerals on credit cards -- proves to be a much more varied and ecological creator of nanostructures than the current method of choice, chemistry, with its unvarying results and harmful chemical processes.

Sandia National Laboratories researcher Hongyou Fan, center, points out a nanoscience result to Sandia paper co-authors Paul Clem, left, and Binsong Li.
Credit: Photo by Randy Montoya, Sandia National Laboratories

You wouldn't think that mechanical force -- the simple kind used to eject unruly patrons from bars, shoe a horse or emboss the raised numerals on credit cards -- could process nanoparticles more subtly than the most advanced chemistry.

Yet, in a current paper in Nature Communications, Sandia National Laboratories researcher Hongyou Fan and colleagues appear to have achieved a start toward that end.

Their newly patented and original method uses simple pressure -- a kind of high-tech embossing -- to produce finer and cleaner results in forming silver nanostructures than do chemical methods, which are not only inflexible in their results but leave harmful byproducts to dispose of.

Fan calls his approach "a simple stress-based fabrication method" that, when applied to nanoparticle arrays, forms new nanostructures with tunable properties.

"There is a great potential market for this technology," he said. "It can be readily and directly integrated into current industrial manufacturing lines without creating new expensive and specialized equipment."

Said Sandia co-author Paul Clem, "This is a foundational method that should enable a variety of devices, including flexible electronics such as antennas, chemical sensors and strain detectors." It also would produce transparent electrodes for solar cells and organic light-emitting diodes, Clem said.

The method was inspired by industrial embossing processes in which a patterned mask is applied with high external pressure to create patterns in the substrate, Fan said. "In our technology, two diamond anvils were used to sandwich nanoparticulate thin films. This external stress manually induced transitions in the film that synthesized new materials," he said.

The pressure, delivered by two diamond plates tightened by four screws to any controlled setting, shepherds silver nanospheres into any desired volume. Propinquity creates conditions that produce nanorods, nanowires and nanosheets at chosen thicknesses and lengths rather than the one-size-fits-all output of a chemical process, with no environmentally harmful residues.

While experiments reported in the paper were performed with silver -- the most desirable metal because it is the most conductive, stable and optically interesting and becomes transparent at certain pressures -- the method also has been shown to work with gold, platinum and other metallic nanoparticles

Clem said the researchers are now starting to work with semiconductors.

Bill Hammetter, manager of Sandia's Advanced Materials Laboratory, said, "Hongyou has discovered a way to build one structure into another structure -- a capability we don't have now at the nanolevel. Eight or nine gigapascal -- the amount of pressure at which phase change and new materials occur -- are not difficult to reach. Any industry that has embossing equipment could lay a film of silver on a piece of paper, build a conductive pattern, then remove the extraneous material and be left with the pattern. A coating of nanoparticles that can build into another structure has a certain functionality we don't have right now. It's a discovery that hasn't been commercialized, but could be done today with the same equipment used by anyone who makes credit cards."

The method can be used to configure new types of materials. For example, under pressure, the dimensions of ordered three-dimensional nanoparticle arrays shrink. By fabricating a structure in which the sandwiching walls permanently provide that pressure, the nanoparticle array will remain at a constant state, able to transmit light and electricity with specific characteristics. This pressure-regulated fine-tuning of particle separation enables controlled investigation of distance-dependent optical and electrical phenomena.

At even higher pressures, nanoparticles are forced to sinter, or bond, forming new classes of chemically and mechanically stable nanostructures that no longer need restraining surfaces. These cannot be manufactured using current chemical methods.

Depending on the size, composition and phase orientation of the initial nanoparticle arrays, a variety of nanostructures or nanocomposites and 3-D interconnected networks are achievable.

The stress-induced synthesis processes are simple and clean. No thermal processing or further purification is needed to remove reaction byproducts.

This work was funded by the Department of Energy's Office of Science. Other authors of the paper are from Cornell University and Los Alamos National Laboratory.

Sandia National Laboratories is a multi-program laboratory operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corp., for the U.S. Department of Energy's National Nuclear Security Administration. With main facilities in Albuquerque, N.M., and Livermore, Calif., Sandia has major R&D responsibilities in national security, energy and environmental technologies and economic competitiveness.


Story Source:

The above story is based on materials provided by Sandia National Laboratories. Note: Materials may be edited for content and length.


Journal Reference:

  1. Binsong Li, Xiaodong Wen, Ruipeng Li, Zhongwu Wang, Paul G. Clem, Hongyou Fan. Stress-induced phase transformation and optical coupling of silver nanoparticle superlattices into mechanically stable nanowires. Nature Communications, 2014; 5 DOI: 10.1038/ncomms5179

Cite This Page:

Sandia National Laboratories. "Diamond plates create nanostructures through pressure, not chemistry." ScienceDaily. ScienceDaily, 27 June 2014. <www.sciencedaily.com/releases/2014/06/140627133105.htm>.
Sandia National Laboratories. (2014, June 27). Diamond plates create nanostructures through pressure, not chemistry. ScienceDaily. Retrieved July 28, 2014 from www.sciencedaily.com/releases/2014/06/140627133105.htm
Sandia National Laboratories. "Diamond plates create nanostructures through pressure, not chemistry." ScienceDaily. www.sciencedaily.com/releases/2014/06/140627133105.htm (accessed July 28, 2014).

Share This




More Matter & Energy News

Monday, July 28, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

The Carbon Trap: US Exports Global Warming

The Carbon Trap: US Exports Global Warming

AP (July 28, 2014) AP Investigation: As the Obama administration weans the country off dirty fuels, energy companies are ramping-up overseas coal exports at a heavy price. (July 28) Video provided by AP
Powered by NewsLook.com
Shipping Crates Get New 'lease' On Life

Shipping Crates Get New 'lease' On Life

Reuters - Business Video Online (July 25, 2014) Shipping containers have been piling up as America imports more than it exports. Some university students in Washington D.C. are set to get a first-hand lesson in recycling. Their housing is being built using refashioned shipping containers. Lily Jamali reports. Video provided by Reuters
Powered by NewsLook.com
Europe's Highest Train Turns 80 in French Pyrenees

Europe's Highest Train Turns 80 in French Pyrenees

AFP (July 25, 2014) Europe's highest train, the little train of Artouste in the French Pyrenees, celebrates its 80th birthday. Duration: 01:05 Video provided by AFP
Powered by NewsLook.com
TSA Administrator on Politics and Flight Bans

TSA Administrator on Politics and Flight Bans

AP (July 24, 2014) TSA administrator, John Pistole's took part in the Aspen Security Forum 2014, where he answered questions on lifting of the ban on flights into Israel's Tel Aviv airport and whether politics played a role in lifting the ban. (July 24) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins