Nanotechnology Now

Our NanoNews Digest Sponsors





Heifer International

Wikipedia Affiliate Button


android tablet pc

Home > Press > Straintronics: Engineers create piezoelectric graphene

This illustration shows lithium atoms (red) adhered to a graphene lattice that will produce electricity when bent, squeezed or twisted. Conversely, the graphene will deform when an electric field is applied, opening new possibilities in nanotechnology. Illustration: Mitchell Ong, Stanford School of Engineering
This illustration shows lithium atoms (red) adhered to a graphene lattice that will produce electricity when bent, squeezed or twisted. Conversely, the graphene will deform when an electric field is applied, opening new possibilities in nanotechnology. Illustration: Mitchell Ong, Stanford School of Engineering

Abstract:
By depositing atoms on one side of a grid of the "miracle material" graphene, researchers at Stanford have engineered piezoelectricity into a nanoscale material for the first time. The implications could yield dramatic degree of control in nanotechnology.

Straintronics: Engineers create piezoelectric graphene

Stanford, CA | Posted on March 21st, 2012

By Andrew Myers

In what became known as the ‘Scotch tape technique," researchers first extracted graphene with a piece of adhesive in 2004. Graphene is a single layer of carbon atoms arranged in a honeycomb, hexagonal pattern. It looks like chicken wire.

Graphene is a wonder material. It is a one-hundred-times-better conductor of electricity than silicon. It is stronger than diamond. And, at just one atom thick, it is so thin as to be essentially a two-dimensional material. Such promising physics have made graphene the most studied substance of the last decade, particularly in nanotechnology. In 2010, the researchers who first isolated it shared the Nobel Prize.

Yet, while graphene is many things, it is not piezoelectric. Piezoelectricity is the property of some materials to produce electric charge when bent, squeezed or twisted. Perhaps more importantly, piezoelectricity is reversible. When an electric field is applied, piezoelectric materials change shape, yielding a remarkable level of engineering control.

Piezoelectrics have found application in countless devices from watches, radios and ultrasound to the push-button starters on propane grills, but these uses all require relatively large, three-dimensional quantities of piezoelectric materials.

Now, in a paper published in the journal ACS Nano, two materials engineers at Stanford have described how they have engineered piezoelectrics into graphene, extending for the first time such fine physical control to the nanoscale.
Straintronics

"The physical deformations we can create are directly proportional to the electrical field applied. This represents a fundamentally new way to control electronics at the nanoscale," said Evan Reed, head of the Materials Computation and Theory Group at Stanford and senior author of the study.

This phenomenon brings new dimension to the concept of ‘straintronics,' he said, because of the way the electrical field strains—or deforms—the lattice of carbon, causing it to change shape in predictable ways.

"Piezoelectric graphene could provide an unparalleled degree of electrical, optical or mechanical control for applications ranging from touchscreens to nanoscale transistors," said Mitchell Ong, a post-doctoral scholar in Reed's lab and first author of the paper.

Using a sophisticated modeling application running on high-performance supercomputers, the engineers simulated the deposition of atoms on one side of a graphene lattice — a process known as doping — and measured the piezoelectric effect.

They modeled graphene doped with lithium, hydrogen, potassium and fluorine, as well as combinations of hydrogen and fluorine and lithium and fluorine on either side of the lattice. Doping just one side of the graphene, or doping both sides with different atoms, is key to the process as it breaks graphene's perfect physical symmetry, which otherwise cancels the piezoelectric effect.

The results surprised both engineers.

"We thought the piezoelectric effect would be present, but relatively small. Yet, we were able to achieve piezoelectric levels comparable to traditional three-dimensional materials," said Reed. "It was pretty significant."
Designer piezoelectricity

The researchers were further able to fine tune the effect by pattern doping the graphene—selectively placing atoms in specific sections and not others.

"We call it designer piezoelectricity because it allows us to strategically control where, when and how much the graphene is deformed by an applied electrical field with promising implications for engineering," said Ong.

While the results in creating piezoelectric graphene are encouraging, the researchers believe that their technique might further be used to engineer piezoelectricity in nanotubes and other nanomaterials with applications ranging from electronics, photonics, and energy harvesting to chemical sensing and high-frequency acoustics.

"We're already looking at new piezoelectric devices based on other 2D and low-dimensional materials, hoping they might open new and dramatic possibilities in nanotechnology," said Reed.

The Army High Performance Computing Research Center at Stanford University and the National Energy Research Scientific Computing Center (NERSC) at the Lawrence Berkeley National Laboratory supported this research.

Listen to Reed and Ong talk about their work with ACS Nano: /www.stanford.edu/group/evanreed/media/ancac3-0212.mp3

Andrew Myers is the associate director of communications for the Stanford University School of Engineering.

####

For more information, please click here

Contacts:
Andrew Myers
Associate Director of Communications
650.736.2245


Jamie Beckett
Director of Communications and Alumni Relations
650.736.2241

Copyright © Stanford School of Engineering

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

East China University of Science and Technology Purchases Nanonex Advanced Nanoimprint Tool NX-B200 July 30th, 2014

Watching Schrödinger's cat die (or come to life): Steering quantum evolution & using probes to conduct continuous error correction in quantum computers July 30th, 2014

From Narrow to Broad July 30th, 2014

FLAG-ERA and TNT2014 join efforts: Graphene Networking at its higher level in Barcelona: Encourage the participation in a joint transnational call July 30th, 2014

New Objective Focusing Nanopositioner from nPoint July 30th, 2014

Graphene

FLAG-ERA and TNT2014 join efforts: Graphene Networking at its higher level in Barcelona: Encourage the participation in a joint transnational call July 30th, 2014

Tough foam from tiny sheets: Rice University lab uses atom-thick materials to make ultralight foam July 29th, 2014

Silicene Labs Announces the Launch of Patent-Pending, 2D Materials Composite Index™ : The Initial 2D Materials Composite Index™ for Q2 2014 Is: 857.3; Founders Include World-Renowned Physicist and Seasoned Business and IP Professionals July 24th, 2014

Penn Study: Understanding Graphene’s Electrical Properties on an Atomic Level July 22nd, 2014

Laboratories

Stanford team achieves 'holy grail' of battery design: A stable lithium anode - Engineers use carbon nanospheres to protect lithium from the reactive and expansive problems that have restricted its use as an anode July 27th, 2014

NIST shows ultrasonically propelled nanorods spin dizzyingly fast July 22nd, 2014

Govt.-Legislation/Regulation/Funding/Policy

New imaging agent provides better picture of the gut July 30th, 2014

Watching Schrödinger's cat die (or come to life): Steering quantum evolution & using probes to conduct continuous error correction in quantum computers July 30th, 2014

Nature inspires a greener way to make colorful plastics July 30th, 2014

Tough foam from tiny sheets: Rice University lab uses atom-thick materials to make ultralight foam July 29th, 2014

Nanotubes/Buckyballs

SouthWest NanoTechnologies Names NanoSperse as A SWeNT Certified Compounder July 29th, 2014

A new way to make microstructured surfaces: Method can produce strong, lightweight materials with specific surface properties July 29th, 2014

UCF Nanotech Spinout Developing Revolutionary Battery Technology: Power the Next Generation of Electronics with Carbon July 23rd, 2014

University of Houston researchers create new method to draw molecules from live cells: Technique using magnetic nanomaterials offers promise for diagnosis, gene therapy July 17th, 2014

Discoveries

New imaging agent provides better picture of the gut July 30th, 2014

Watching Schrödinger's cat die (or come to life): Steering quantum evolution & using probes to conduct continuous error correction in quantum computers July 30th, 2014

From Narrow to Broad July 30th, 2014

A new way to make microstructured surfaces: Method can produce strong, lightweight materials with specific surface properties July 29th, 2014

Announcements

University of Manchester selects Anasys AFM-IR for coatings and corrosion research July 30th, 2014

Nature inspires a greener way to make colorful plastics July 30th, 2014

Analytical solutions from Malvern Instruments support University of Wisconsin-Milwaukee researchers in understanding environmental effects of nanomaterials July 30th, 2014

FEI Unveils New Solutions for Faster Time-to-Analysis in Metals Research July 30th, 2014

Military

New imaging agent provides better picture of the gut July 30th, 2014

Watching Schrödinger's cat die (or come to life): Steering quantum evolution & using probes to conduct continuous error correction in quantum computers July 30th, 2014

Tough foam from tiny sheets: Rice University lab uses atom-thick materials to make ultralight foam July 29th, 2014

A new way to make microstructured surfaces: Method can produce strong, lightweight materials with specific surface properties July 29th, 2014

Battery Technology/Capacitors/Generators/Piezoelectrics/Thermoelectrics

Tough foam from tiny sheets: Rice University lab uses atom-thick materials to make ultralight foam July 29th, 2014

Stanford team achieves 'holy grail' of battery design: A stable lithium anode - Engineers use carbon nanospheres to protect lithium from the reactive and expansive problems that have restricted its use as an anode July 27th, 2014

Nano-supercapacitors for electric cars July 25th, 2014

Compact Vibration Harvester Power Supply with Highest Efficiency Opens Door to “Fix-and-Forget” Sensor Nodes July 23rd, 2014

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 1999-2014 7th Wave, Inc. All Rights Reserved PRIVACY POLICY :: CONTACT US :: STATS :: SITE MAP :: ADVERTISE