Featured Research

from universities, journals, and other organizations

Making new materials an atomic layer at a time

Date:
April 16, 2014
Source:
Penn State Materials Research Institute
Summary:
Researchers have shown the ability to grow high quality, single-layer materials one on top of the other using chemical vapor deposition. This highly scalable technique, often used in the semiconductor industry, can produce new materials with unique properties that could be applied to solar cells, ultracapacitors for energy storage, or advanced transistors for energy efficient electronics, among many other applications.

A photosensor fabricated on the MoS2/graphene heterostructure.
Credit: Yu-Chuan Lin, Penn State

Researchers at Penn State's Center for 2-Dimensional and Layered Materials and the University of Texas at Dallas have shown the ability to grow high quality, single-layer materials one on top of the other using chemical vapor deposition. This highly scalable technique, often used in the semiconductor industry, can produce new materials with unique properties that could be applied to solar cells, ultracapacitors for energy storage, or advanced transistors for energy efficient electronics, among many other applications.

"People have been trying to stack these layered materials using the scotch tape method (an exfoliation method developed by Nobel laureates Novoselov and Geim to produce graphene), but that leaves residue on the layers and is not scalable," explains Joshua Robinson of Penn State, corresponding author on a recent article published online in ACS Nano. Other groups have utilized the chemical vapor deposition method to grow layered materials on a copper substrate, but this method requires some sophisticated techniques to transfer the layered material to a more functional substrate without causing tears or contamination.

Robinson and his colleagues employed a more direct method, using chemical vapor deposition to grow a layer of quasi-free-standing epitaxial graphene (QFEG) on a silicon carbide substrate, followed by a layer of molybdenum disulfide (MoS2), a metal dichalcogenide compound widely used as a lubricant. In order to test the quality of the MoS2 on graphene, the researchers used the material to build a photodetector device to measure the layered material's efficiency at converting photons to electrons. They found that the response of the MoS2/QFEG material was 100 times higher than MoS2 alone.

For devices, the QFEG method, which introduces a layer of hydrogen atoms between the substrate and the graphene and thereby decouples the graphene layer from the underlying silicon carbide, proved to be a better choice than the more standard as-grown graphene. Robinson says, "In general QFEG is more interesting, and from a device point of view, it's critical."

To see if quasi-free-standing graphene was a suitable template for the growth of other artificially stacked atomic layers, the team synthesized two other van der Waals solids: tungsten diselenide, and hexagonal boron nitride. (van der Waals solids have strong in-plane bonding but weak interlayer bonding.) They determined that epitaxial graphene was "an excellent candidate for building large-area vdW solids that will have extraordinary properties and performances."

Industry has already shown strong interest in 2D layered materials for RF applications, low-power and low-cost semiconductors, and for displays on flexible substrates. "This is the first step," Robinson says. "To truly control properties we will need to look at a variety of these systems that should turn out to have entirely new properties when stacked together."


Story Source:

The above story is based on materials provided by Penn State Materials Research Institute. Note: Materials may be edited for content and length.


Journal Reference:

  1. Yu-Chuan Lin, Ning Lu, Nestor Perea-Lopez, Jie Li, Zhong Lin, Xin Peng, Chia Hui Lee, Ce Sun, Lazaro Calderin, Paul N. Browning, Michael S. Bresnehan, Moon J. Kim, Theresa S. Mayer, Mauricio Terrones, Joshua A. Robinson. Direct Synthesis of van der Waals Solids. ACS Nano, 2014; 140327142021003 DOI: 10.1021/nn5003858

Cite This Page:

Penn State Materials Research Institute. "Making new materials an atomic layer at a time." ScienceDaily. ScienceDaily, 16 April 2014. <www.sciencedaily.com/releases/2014/04/140416112710.htm>.
Penn State Materials Research Institute. (2014, April 16). Making new materials an atomic layer at a time. ScienceDaily. Retrieved October 20, 2014 from www.sciencedaily.com/releases/2014/04/140416112710.htm
Penn State Materials Research Institute. "Making new materials an atomic layer at a time." ScienceDaily. www.sciencedaily.com/releases/2014/04/140416112710.htm (accessed October 20, 2014).

Share This



More Matter & Energy News

Monday, October 20, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

'Robotic Eyes' Helps Japan's Bipedal Bot Run Faster

'Robotic Eyes' Helps Japan's Bipedal Bot Run Faster

Reuters - Innovations Video Online (Oct. 16, 2014) Japanese researcher uses an eye-sensor camera to enable a bipedal robot to balance itself, while running on a treadmill. Jim Drury reports. Video provided by Reuters
Powered by NewsLook.com
Lockheed Martin's Fusion Concept Basically An Advertisement

Lockheed Martin's Fusion Concept Basically An Advertisement

Newsy (Oct. 15, 2014) Lockheed Martin announced plans to develop the first-ever compact nuclear fusion reactor. But some experts said the excitement is a little premature. Video provided by Newsy
Powered by NewsLook.com
First Confirmed Case Of Google Glass Addiction

First Confirmed Case Of Google Glass Addiction

Buzz60 (Oct. 15, 2014) A Google Glass user was treated for Internet Addiction Disorder caused from overuse of the device. Morgan Manousos (@MorganManousos) has the details on how many hours he spent wearing the glasses, and what his symptoms were. Video provided by Buzz60
Powered by NewsLook.com
Science Proves Why Pizza Is So Delicious

Science Proves Why Pizza Is So Delicious

Buzz60 (Oct. 15, 2014) The American Chemical Society’s latest video about chemistry in every day life breaks down pizza, and explains exactly why it's so delicious. Gillian Pensavalle (@GillianWithaG) has the video. Video provided by Buzz60
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Space & Time

Matter & Energy

Computers & Math

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins