Navigation Links
3-dimensional view of 1-dimensional nanostructures
Date:1/6/2012

Just 100 nanometers in diameter, nanowires are often considered one-dimensional. But researchers at Northwestern University have recently reported that individual gallium nitride nanowires show strong piezoelectricity a type of charge-generation caused by mechanical stress in three dimensions.

The findings, led by Horacio Espinosa, James N. and Nancy J. Farley Professor in Manufacturing and Entrepreneurship at the McCormick School of Engineering and Applied Science, were published online Dec. 22 in Nano Letters.

Gallium nitride (GaN) is among the most technologically relevant semiconducting materials and is ubiquitous today in optoelectronic elements such as blue lasers (hence the blue-ray disc) and light-emitting-diodes (LEDs). More recently, nanogenerators based on GaN nanowires were demonstrated capable of converting mechanical energy (such as biomechanical motion) to electrical energy.

"Although nanowires are one-dimensional nanostructures, some properties such as piezoelectricity, the linear form of electro-mechanical coupling are three-dimensional in nature," Espinosa said. "We thought these nanowires should show piezoelectricity in 3D, and aimed at obtaining all the piezoelectric constants for individual nanowires, similar to the bulk material."

The findings revealed that individual GaN nanowires as small as 60 nanometers show piezoelectric behavior in 3D up to six times of their bulk counterpart. Since the generated charge scales linearly with piezoelectric constants, this finding implies that nanowires are up to six times more efficient in converting mechanical to electrical energy.

To obtain the measurements, researchers applied an electric field in different directions in single nanowire and measured small displacements, often in pico-meter (10-12 m) range. The group devised a method based on scanning probe microscopy leveraging high-precision displacement measurement capability of an atomic force microscope.

"The measurements were very challenging, since we needed to accurately measure displacements 100 times smaller than the size of the hydrogen atom," said Majid Minary, a postdoctoral fellow and the lead author of the study.

These results are exciting especially considering the recent demonstration of nanogenerators based on GaN nanowires, for powering of self-powered nanodevices.


'/>"/>
Contact: Megan Fellman
fellman@northwestern.edu
847-491-3115
Northwestern University
Source:Eurekalert  

Related biology technology :

1. Heated AFM tip allows direct fabrication of ferroelectric nanostructures on plastic
2. Intricate, curving 3-D nanostructures created using capillary action forces
3. High-speed filter uses electrified nanostructures to purify water at low cost
4. New security and medical sensor devices made possible by metallic nanostructures
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
3-dimensional view of 1-dimensional nanostructures
(Date:2/28/2017)... and REYKJAVIK, Iceland , Feb. 28, ... group company and the contract genomics organization enabling precision ... Hannes Smarason has been appointed as the company,s chief executive ... and Alex Fowkes have been named chief ... "WuXi NextCODE is executing on its vision to enable anyone ...
(Date:2/28/2017)... 2017  Xencor, Inc. (NASDAQ: XNCR), a clinical-stage biopharmaceutical ... of autoimmune diseases, asthma and allergic diseases and ... quarter and full year ended December 31, 2016 ... business and clinical highlights. "During 2016, ... pipeline by starting five clinical trials across our ...
(Date:2/28/2017)... ... February 28, 2017 , ... The ... well as to their processing and transport properties. With the Litesizerâ„¢ 100 ... of samples. The Litesizerâ„¢ 100 gives rapid and accurate insight into particle systems, ...
(Date:2/28/2017)... (PRWEB) , ... February 28, 2017 , ... ... trials, yet requires extensive coordination and expertise. Colpitts Clinical Trial Travel and ... 15 years of meeting this unique need within the biotechnology and pharmaceutical industries ...
Breaking Biology Technology:
(Date:2/16/2017)... , Feb. 16, 2017  Genos, a ... announced that it has received Laboratory Accreditation from ... Accreditation is presented to laboratories that meet stringent ... demonstrate scientifically rigorous processes. "Genos is ... in laboratory practices. We,re honored to be receiving ...
(Date:2/13/2017)...  RSA Conference -- RSA, a Dell Technologies business, ... enhance fraud detection and investigation across digital environments ... & Risk Intelligence Suite. The new platform is ... from internal and external sources as well as ... from targeted cybercrime attacks. "Fraudsters are ...
(Date:2/10/2017)... DUBLIN , Feb 10, 2017 ... PharmaBiotech,s new report "Personalized Medicine - Scientific and Commercial ... ... in personalized medicine. Diagnosis is integrated with therapy for selection ... emphasis on early detection and prevention of disease in modern ...
Breaking Biology News(10 mins):