Nanotechnology Now







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

'Atomic chicken-wire' is key to faster DNA sequencing March 30th, 2015

Nanoscale worms provide new route to nano-necklace structures March 29th, 2015

Solving molybdenum disulfide's 'thin' problem: Research team increases material's light emission by twelve times March 29th, 2015

A first glimpse inside a macroscopic quantum state March 28th, 2015

DFG to Establish One Clinical Research Unit and Five Research Units: New Projects to Investigate Complications in Pregnancy, Particle Physics, Nanoparticles, Implants and Transport Planning / Approximately 13 Million Euros in Funding for an Initial Three-Year Period March 28th, 2015

Display technology/LEDs/SS Lighting/OLEDs

Solving molybdenum disulfide's 'thin' problem: Research team increases material's light emission by twelve times March 29th, 2015

Haydale Announce Dedicated Graphene Inks Manufacturing Capability March 25th, 2015

Chemistry

Chemists make new silicon-based nanomaterials March 27th, 2015

First proof of isolated attosecond pulse generation at the carbon K-edge March 20th, 2015

Click! That's how modern chemistry bonds nanoparticles to a substrate March 19th, 2015

Govt.-Legislation/Regulation/Funding/Policy

Nanoscale worms provide new route to nano-necklace structures March 29th, 2015

UT Dallas engineers twist nanofibers to create structures tougher than bulletproof vests March 27th, 2015

Novel nanoparticle therapy promotes wound healing March 27th, 2015

Designer's toolkit for dynamic DNA nanomachines: Arm-waving nanorobot signals new flexibility in DNA origami March 27th, 2015

Discoveries

'Atomic chicken-wire' is key to faster DNA sequencing March 30th, 2015

Nanoscale worms provide new route to nano-necklace structures March 29th, 2015

Solving molybdenum disulfide's 'thin' problem: Research team increases material's light emission by twelve times March 29th, 2015

A first glimpse inside a macroscopic quantum state March 28th, 2015

Announcements

'Atomic chicken-wire' is key to faster DNA sequencing March 30th, 2015

Nanoscale worms provide new route to nano-necklace structures March 29th, 2015

Solving molybdenum disulfide's 'thin' problem: Research team increases material's light emission by twelve times March 29th, 2015

A first glimpse inside a macroscopic quantum state March 28th, 2015

Tools

'Atomic chicken-wire' is key to faster DNA sequencing March 30th, 2015

LAMDAMAP 2015 hosted by the University March 26th, 2015

FEI Technology Award of the German Neuroscience Society Goes to Benjamin Judkewitz of the University of Berlin: Bi-annual award honors excellence in brain research during the German Neuroscience Society’s Annual Meeting, held 18-21 March 2015 March 26th, 2015

Square ice filling for a graphene sandwich March 26th, 2015

Military

Nanoscale worms provide new route to nano-necklace structures March 29th, 2015

UT Dallas engineers twist nanofibers to create structures tougher than bulletproof vests March 27th, 2015

Novel nanoparticle therapy promotes wound healing March 27th, 2015

Thousands of atoms entangled with a single photon: Result could make atomic clocks more accurate March 26th, 2015

Photonics/Optics/Lasers

Solving molybdenum disulfide's 'thin' problem: Research team increases material's light emission by twelve times March 29th, 2015

A first glimpse inside a macroscopic quantum state March 28th, 2015

Chemists make new silicon-based nanomaterials March 27th, 2015

Bar-Ilan U. researchers identify 'tipping point' between quantum and classical worlds: Study sheds new light on 'spooky' quantum optics March 24th, 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