Nanotechnology Now

Our NanoNews Digest Sponsors





Heifer International

Wikipedia Affiliate Button


DHgate

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

Transparent, electrically conductive network of encapsulated silver nanowires: A novel electrode for optoelectronics August 1st, 2015

Harris & Harris Group Portfolio Company, HZO, Announces Partnerships with Dell and Motorola August 1st, 2015

Advances and Applications in Biosensing, Sensor Power, and Sensor R&D to be Covered at Sensors Global Summit August 1st, 2015

Kalam: versatility personified August 1st, 2015

Chemistry

March 2016; 6th Int'l Conference on Nanostructures in Iran July 29th, 2015

Meet the high-performance single-molecule diode: Major milestone in molecular electronics scored by Berkeley Lab and Columbia University team July 29th, 2015

'Seeing' molecular interactions could give boost to organic electronics July 28th, 2015

Display technology/LEDs/SS Lighting/OLEDs

Controlling phase changes in solids: Controlling phase changes in solids July 29th, 2015

Liquipel Debuts Eyesight-Saving ION-Glass Blue Light Protection for iPhones and Androids at RadioShack Stores Nationwide: Liquipel's Unique Protective Screen, Available at RadioShack, Cuts Harmful Blue Light Implicated in Macular Degeneration by 10x July 28th, 2015

'Seeing' molecular interactions could give boost to organic electronics July 28th, 2015

Govt.-Legislation/Regulation/Funding/Policy

Self-assembling, biomimetic membranes may aid water filtration August 1st, 2015

Kalam: versatility personified August 1st, 2015

Heating and cooling with light leads to ultrafast DNA diagnostics July 31st, 2015

Theoretical Physicists at Freie Universität Berlin Develop New Insights into Interface between Classical and Quantum Worlds July 31st, 2015

Discoveries

Gold-diamond nanodevice for hyperlocalised cancer therapy: Gold nanorods can be used as remote controlled nanoheaters delivering the right amount of thermal treatment to cancer cells, thanks to diamond nanocrystals used as temperature sensors August 1st, 2015

Shaping the hilly landscapes of a semi-conductor nanoworld August 1st, 2015

Solid state physics: Quantum matter stuck in unrest August 1st, 2015

Self-assembling, biomimetic membranes may aid water filtration August 1st, 2015

Announcements

Self-assembling, biomimetic membranes may aid water filtration August 1st, 2015

Transparent, electrically conductive network of encapsulated silver nanowires: A novel electrode for optoelectronics August 1st, 2015

Harris & Harris Group Portfolio Company, HZO, Announces Partnerships with Dell and Motorola August 1st, 2015

Advances and Applications in Biosensing, Sensor Power, and Sensor R&D to be Covered at Sensors Global Summit August 1st, 2015

Tools

Heating and cooling with light leads to ultrafast DNA diagnostics July 31st, 2015

Take a trip through the brain July 30th, 2015

Publication on Atomic Force Microscopy based nanoscale IR Spectroscopy (AFM-IR) persists as a 2015 top downloaded paper July 29th, 2015

Nanometrics Announces Upcoming Investor Events July 28th, 2015

Military

Self-assembling, biomimetic membranes may aid water filtration August 1st, 2015

Take a trip through the brain July 30th, 2015

Sol-gel capacitor dielectric offers record-high energy storage July 30th, 2015

Reshaping the solar spectrum to turn light to electricity: UC Riverside researchers find a way to use the infrared region of the sun's spectrum to make solar cells more efficient July 27th, 2015

Photonics/Optics/Lasers

Heating and cooling with light leads to ultrafast DNA diagnostics July 31st, 2015

IEEE Photonics Society Applauds Rochester on Integrated Photonics Institute Win July 30th, 2015

March 2016; 6th Int'l Conference on Nanostructures in Iran July 29th, 2015

Controlling phase changes in solids: Controlling phase changes in solids July 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