Nanotechnology Now

Our NanoNews Digest Sponsors

Heifer International

Wikipedia Affiliate Button

Home > Press > Light-emitting triangles may have applications in optical technology

Triangular single layers of tungsten disulfide have been synthesized by Penn State researchers. The edges of the triangles exhibit extraordinary photoluminescence, while the interior area does not. The photoluminescent signal disappears as the number of layers increases. These triangular structures may have potential applications in optical technology; for example, for use in light detectors and lasers.

Credit: Terrones lab, Penn State Universtiy
Triangular single layers of tungsten disulfide have been synthesized by Penn State researchers. The edges of the triangles exhibit extraordinary photoluminescence, while the interior area does not. The photoluminescent signal disappears as the number of layers increases. These triangular structures may have potential applications in optical technology; for example, for use in light detectors and lasers.

Credit: Terrones lab, Penn State Universtiy

Abstract:
For the first time, scientists have created single layers of a naturally occurring rare mineral called tungstenite, or WS2. The resulting sheet of stacked sulfur and tungsten atoms forms a honeycomb pattern of triangles that have been shown to have unusual light-emitting, or photoluminescent, properties. According to team leader Mauricio Terrones, a professor of physics and of materials science and engineering at Penn State, the triangular structures have potential applications in optical technology; for example, for use in light detectors and lasers. The results of the research will be published in a print edition of the journal NANO Letters.

Light-emitting triangles may have applications in optical technology

University Park, PA | Posted on February 5th, 2013

Terrones explained that creating monolayers -- single, one-atom-thick layers -- is of special interest to scientists because the chemical properties of minerals and other substances are known to change depending on their atomic thickness, opening the door to potentially useful applications of multi-layered materials of various thicknesses. In previous research, scientists had accomplished the feat of making a monolayer of graphene -- a substance similar to the graphite found in pencil leads. "The technique these researchers used was tedious, but it worked," Terrones said. "They basically removed, or exfoliated, the graphene, layer by layer, with Scotch tape, until they got down to a single atom of thickness."

Now, for the first time, Terrones and his team have used a controlled thermal reduction-sulfurization method -- or chemical vapor deposition -- to accomplish the same feat with a rare mineral called tungstenite. The scientists began by depositing tiny crystals of tungsten oxide, which are less than one nanometer in height, and they then passed the crystals through sulfur vapor at 850 degrees Celsius. This process led to individual layers -- or sheets -- composed of one atom in thickness. The resulting structure -- called tungsten disulfide -- is a honeycomb pattern of triangles consisting of tungsten atoms bonded with sulfur atoms.

"One of the most exciting properties of the tungsten disulfide monolayer is its photoluminescence," Terrones said. Terrones explained that photoluminescence occurs when a substance absorbs light at one wavelength and re-emits that light at a different wavelength. The property of photoluminescence also occurs in certain bioluminescenent animals such as angler fish and fireflies. "One interesting discovery from our work is the fact that we see the strongest photoluminescence at the edges of the triangles, right where the chemistry of the atoms changes, with much less photoluminescence occurring in the center of the triangles," Terrones said. "We also have found that these new monolayers luminesce at room temperature. So no special temperature requirements are needed for the material to exhibit this property."

Co-author Vincent H. Crespi, Distinguished Professor of Physics, Chemistry, and Materials Science and Engineering at Penn State, added, "The images of the photoluminescence are beautiful; the triangles light up all around their edges like little holiday ornaments -- holiday ornaments with potentially transformative, long-term applications in nano-optics."

The research has many potential applications in the fields of optical light detection, the production of light-emitting diodes, and even laser technology. The researchers also plan to try the chemical-vapor-deposition technology to grow innovative monolayers using other layered materials with potentially useful applications.

In addition to Terrones and Crespi, other researchers who contributed to this study include Humberto R. Gutiérrez, an assistant professor at the University of Louisville; Nestor Perea-López and Ana Laura Elías, research associates at Penn State; Ayse Berkdemir and Ruitao Lv, posdoctoral fellows at Penn State; Bei Wang and Yuanxi Wang, graduate students at Penn State; and Florentino López-Urías and Humberto Terrones, visiting professors at Penn State.

Support for this research comes primarily from the U.S. Army Research Office and, in part, from the Penn State Center for Nanoscale Science.

[ Katrina Voss ]

GRANT NUMBERS: U.S. Army Research Office (MURI grant W911NF-11-1-0362), Penn State Center for Nanoscale Science (DMR-0820404)

####

For more information, please click here

Contacts:
Barbara Kennedy

814-863-4682

Mauricio Terrones:
814-865-0343


Vincent H. Crespi
814-863-0163

Copyright © Penn State

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

Chemists Cook up New Nanomaterial and Imaging Method: Nanomaterials can store all kinds of things, including energy, drugs and other cargo January 19th, 2017

National Space Society Congratulates SpaceX on the Falcon 9's Return to Flight January 19th, 2017

Eric Berger Wins the National Space Society's 2017 Space Pioneer Award for Mass Media January 19th, 2017

Nanometrics to Announce Fourth Quarter and Full Year Financial Results on February 7, 2017 January 19th, 2017

Display technology/LEDs/SS Lighting/OLEDs

Self-assembling particles brighten future of LED lighting January 18th, 2017

Dressing a metal in various colors: DGIST research developed a technology to coat metal with several nanometers of semiconducting materials January 17th, 2017

Miniscule amounts of impurities in vacuum greatly affecting OLED lifetime December 30th, 2016

Chemistry

Chemistry on the edge: Experiments at Berkeley Lab confirm that structural defects at the periphery are key in catalyst function January 13th, 2017

Researchers produced nitrogen doped bimodal cellular structure activated carbon December 29th, 2016

Safe and inexpensive hydrogen production as a future energy source: Osaka University researchers develop efficient 'green' hydrogen production system that operates at room temperature in air December 21st, 2016

Govt.-Legislation/Regulation/Funding/Policy

'5-D protein fingerprinting' could give insights into Alzheimer's, Parkinson's January 19th, 2017

Strength of hair inspires new materials for body armor January 18th, 2017

Self-assembling particles brighten future of LED lighting January 18th, 2017

Nanoscale view of energy storage January 16th, 2017

Discoveries

Chemists Cook up New Nanomaterial and Imaging Method: Nanomaterials can store all kinds of things, including energy, drugs and other cargo January 19th, 2017

'5-D protein fingerprinting' could give insights into Alzheimer's, Parkinson's January 19th, 2017

Strength of hair inspires new materials for body armor January 18th, 2017

Self-assembling particles brighten future of LED lighting January 18th, 2017

Announcements

Chemists Cook up New Nanomaterial and Imaging Method: Nanomaterials can store all kinds of things, including energy, drugs and other cargo January 19th, 2017

National Space Society Congratulates SpaceX on the Falcon 9's Return to Flight January 19th, 2017

Eric Berger Wins the National Space Society's 2017 Space Pioneer Award for Mass Media January 19th, 2017

Nanometrics to Announce Fourth Quarter and Full Year Financial Results on February 7, 2017 January 19th, 2017

Tools

Chemists Cook up New Nanomaterial and Imaging Method: Nanomaterials can store all kinds of things, including energy, drugs and other cargo January 19th, 2017

Nanometrics to Announce Fourth Quarter and Full Year Financial Results on February 7, 2017 January 19th, 2017

Distinguishing truth under the surface: electrostatic or mechanic December 31st, 2016

Nanomechanics Inc. Continues Growth in Revenue and Market Penetration: Leading nanoindentation company reports continued growth in revenues and distribution channels on national and international scales December 27th, 2016

Military

'5-D protein fingerprinting' could give insights into Alzheimer's, Parkinson's January 19th, 2017

Strength of hair inspires new materials for body armor January 18th, 2017

Self-assembling particles brighten future of LED lighting January 18th, 2017

Dressing a metal in various colors: DGIST research developed a technology to coat metal with several nanometers of semiconducting materials January 17th, 2017

Photonics/Optics/Lasers

Recreating conditions inside stars with compact lasers: Scientists offer a new path to creating the extreme conditions found in stars, using ultra-short laser pulses irradiating nanowires January 12th, 2017

New laser based on unusual physics phenomenon could improve telecommunications, computing January 12th, 2017

Researcher's discovery of new crystal structure holds promise for optoelectronic devices January 6th, 2017

The researchers created a tiny laser using nanoparticles January 5th, 2017

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