Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


Researchers Create Semiconductor ‘Nano-Shish-Kebabs’ With Potential for 3-D Technologies

Researchers at North Carolina State University have developed a new type of nanoscale structure that resembles a “nano-shish-kebab,” consisting of multiple two-dimensional nanosheets that appear to be impaled upon a one-dimensional nanowire.

However, the nanowire and nanosheets are actually a single, three-dimensional structure consisting of a seamless series of germanium sulfide (GeS) crystals. The structure holds promise for use in the creation of new, three-dimensional (3-D) technologies.

The "shish-kebab" consists of two-dimensional nanosheets strung along a nanowire.

The researchers believe this is the first engineered nanomaterial to combine one-dimensional and two-dimensional structures in which all of the components have a shared crystalline structure.

Combining the nanowire and nanosheets into a single “heterostructure” creates a material with both a large surface area and – because GeS is a semiconductor – the ability to transfer electric charges efficiently. The nanosheets provide a very large surface area, and the nanowire acts as a channel that can transmit charges between the nanosheets or from the nanosheets to another surface. This combination of features means it could be used to develop 3-D devices, such as next-generation sensors, photodetectors or solar cells. This 3-D structure could also be useful for developing new energy storage technologies, such as next-generation supercapacitors.

“We think this approach could also be used to create heterostructures like these using other materials whose molecules form similar crystalline layers, such as molybdenum sulfide (MoS2),” says Dr. Linyou Cao, an assistant professor of materials science and engineering at NC State and co-author of a paper on the research. “And, while germanium sulfide has excellent photonic properties, MoS2 holds more promise for electronic applications.”

The process, Cao says, is also attractive because “it is inexpensive and could be scaled up for industrial processes.”

To create the nano-shish-kebabs, the researchers begin by creating a GeS nanowire approximately 100 nanometers in width. The nanowire is then exposed to air, creating nucleation sites on the wire surface through weak oxidation. The nanowire is then exposed to GeS vapor, which forms into two-dimensional nanosheets at each of the nucleation sites.

“Our next step is to see if we can create these heterostructures in other materials, such as MoS2,” Cao says. “We think we can, but we need to prove it.”

The paper, “Epitaxial Nanosheet–Nanowire Heterostructures,” was published online Feb. 18 in Nano Letters. The lead author is Dr. Chun Li, a former postdoctoral researcher at NC State. Co-authors are Yifei Yu, a Ph.D. student at NC State; Cao; and Dr. Miaofang Chi of Oak Ridge National Laboratory. The research was supported by the U.S. Army Research Office.


Note to Editors: The study abstract follows.

“Epitaxial Nanosheet–Nanowire Heterostructures”

Authors: Chun Li, Yifei Yu and Linyou Cao, North Carolina State University; Miaofang Chi, Oak Ridge National Laboratory

Published: online Feb. 18 in Nano Letters

Abstract: We demonstrate synthesis of a new type of heterostructures that comprise two-dimensional (2D) nanosheets (NSs) epitaxially grown at one-dimensional (1D) nanowires (NWs). The synthesis involves using materials with a graphite-like layered structure in which covalently bonded layers are held by weak van der Waals forces. GeS was used as a prototype material in this work. The synthesis also involves a seeded-growth process, where GeS NWs are grown first as seeds followed by a seeded growth of NSs at the pre-grown NWs. We observe that exposing the pre-grown NWs to air prior to the seeded growth is critical for the formation of NSs to yield NS?NW heterostructures. Our experimental results suggest that this might be due to a mild oxidation caused by the air exposure at the NW surface, which could subsequently facilitate the nucleation of NSs at the NWs. It also suggests that the surface oxidation needs to be controlled in a proper range in order to achieve optimized NS growths. We believe that this synthetic strategy may generally apply to the growth of NS?NW heterostructures of other layered chalcogenide materials.

NS?NW heterostructures provide capabilities to monolithically integrate the functionality of 1D NWs and 2D NSs into a 3D space. It holds great potential in applications that request complex nanomaterials with multiple functionality, high surface area, and efficient charge transport, such as energy storage, chemical sensing, solar energy conversion, and 3D electric and photonic devices.

Matt Shipman | EurekAlert!
Further information:

More articles from Power and Electrical Engineering:

nachricht 'Super yeast' has the power to improve economics of biofuels
18.10.2016 | University of Wisconsin-Madison

nachricht Engineers reveal fabrication process for revolutionary transparent sensors
14.10.2016 | University of Wisconsin-Madison

All articles from Power and Electrical Engineering >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: New 3-D wiring technique brings scalable quantum computers closer to reality

Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.

"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...

Im Focus: Scientists develop a semiconductor nanocomposite material that moves in response to light

In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.

A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...

Im Focus: Diamonds aren't forever: Sandia, Harvard team create first quantum computer bridge

By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.

"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...

Im Focus: New Products - Highlights of COMPAMED 2016

COMPAMED has become the leading international marketplace for suppliers of medical manufacturing. The trade fair, which takes place every November and is co-located to MEDICA in Dusseldorf, has been steadily growing over the past years and shows that medical technology remains a rapidly growing market.

In 2016, the joint pavilion by the IVAM Microtechnology Network, the Product Market “High-tech for Medical Devices”, will be located in Hall 8a again and will...

Im Focus: Ultra-thin ferroelectric material for next-generation electronics

'Ferroelectric' materials can switch between different states of electrical polarization in response to an external electric field. This flexibility means they show promise for many applications, for example in electronic devices and computer memory. Current ferroelectric materials are highly valued for their thermal and chemical stability and rapid electro-mechanical responses, but creating a material that is scalable down to the tiny sizes needed for technologies like silicon-based semiconductors (Si-based CMOS) has proven challenging.

Now, Hiroshi Funakubo and co-workers at the Tokyo Institute of Technology, in collaboration with researchers across Japan, have conducted experiments to...

All Focus news of the innovation-report >>>



Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

Agricultural Trade Developments and Potentials in Central Asia and the South Caucasus

14.10.2016 | Event News

World Health Summit – Day Three: A Call to Action

12.10.2016 | Event News

Latest News

Resolving the mystery of preeclampsia

21.10.2016 | Health and Medicine

Stanford researchers create new special-purpose computer that may someday save us billions

21.10.2016 | Information Technology

From ancient fossils to future cars

21.10.2016 | Materials Sciences

More VideoLinks >>>