Researchers at Penn State have created triangular single layers of tungsten disulfide that exhibit unusual photoluminescent properties and may have potential applications in optical technology.
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 are published online in the journal Nano Letters.
Terrones explained that creating monolayers — single, one-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
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.
Reference: “Extraordinary Room-Temperature Photoluminescence in Triangular WS2 Monolayers” by Humberto R. Gutiérrez, Nestor Perea-López, Ana Laura Elías, Ayse Berkdemir, Bei Wang, Ruitao Lv, Florentino López-Urías, Vincent H. Crespi, Humberto Terrones and Mauricio Terrones, 29 November 2013, Nano Letters.
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.
InfEneTy is a knowledge platform which showcases critical news, insights and features on contemporary and topical issues related to Infrastructure, Energy and Technology affecting the economy, industry sectors, business environment. The intent is to enable an association with the evolving scenario and be a catalyst for change. Help make InfEneTy better. Share your comments or connect with us at firstname.lastname@example.org