Nanotechnology Now

Our NanoNews Digest Sponsors

Heifer International

Wikipedia Affiliate Button

Home > Press > 'Nanocable' could be big boon for energy storage: Rice University's coaxial nanocable outperforms previous microcapacitors

An artist's impression of Rice University's new coaxial nanocable, which is about a thousand times smaller than a human hair.
CREDIT: Zheng Liu/Rice University
An artist's impression of Rice University's new coaxial nanocable, which is about a thousand times smaller than a human hair.

CREDIT: Zheng Liu/Rice University

Abstract:
Thanks to a little serendipity, researchers at Rice University have created a tiny coaxial cable that is about a thousand times smaller than a human hair and has higher capacitance than previously reported microcapacitors.

'Nanocable' could be big boon for energy storage: Rice University's coaxial nanocable outperforms previous microcapacitors

Houston, TX | Posted on June 7th, 2012

The nanocable, which is described this week in Nature Communications, was produced with techniques pioneered in the nascent graphene research field and could be used to build next-generation energy-storage systems. It could also find use in wiring up components of lab-on-a-chip processors, but its discovery is owed partly to chance.

"We didn't expect to create this when we started," said study co-author Jun Lou, associate professor of mechanical engineering and materials science at Rice. "At the outset, we were just curious to see what would happen electrically and mechanically if we took small copper wires known as interconnects and covered them with a thin layer of carbon."

The tiny coaxial cable is remarkably similar in makeup to the ones that carry cable television signals into millions of homes and offices. The heart of the cable is a solid copper wire that is surrounded by a thin sheath of insulating copper oxide. A third layer, another conductor, surrounds that. In the case of TV cables, the third layer is copper again, but in the nanocable it is a thin layer of carbon measuring just a few atoms thick. The coax nanocable is about 100 nanometers, or 100 billionths of a meter, wide.

While the coaxial cable is a mainstay of broadband telecommunications, the three-layer, metal-insulator-metal structure can also be used to build energy-storage devices called capacitors. Unlike batteries, which rely on chemical reactions to both store and supply electricity, capacitors use electrical fields. A capacitor contains two electrical conductors, one negative and the other positive, that are separated by thin layer of insulation. Separating the oppositely charged conductors creates an electrical potential, and that potential increases as the separated charges increase and as the distance between them - occupied by the insulating layer -- decreases. The proportion between the charge density and the separating distance is known as capacitance, and it's the standard measure of efficiency of a capacitor.

The study reports that the capacitance of the nanocable is at least 10 times greater than what would be predicted with classical electrostatics.

"The increase is most likely due to quantum effects that arise because of the small size of the cable," said study co-author Pulickel Ajayan, Rice's Benjamin M. and Mary Greenwood Anderson Professor of Mechanical Engineering and Materials Science.

Lou's and Ajayan's laboratories each specialize in fabricating and studying nanoscale materials and nanodevices that exhibit these types of intriguing quantum effects, but Ajayan and Lou said there was an element of chance to the nanocable discovery.

When the project began 18 months ago, Rice postdoctoral researcher Zheng Liu, the lead co-author of the study, intended to make pure copper wires covered with carbon. The techniques for making the wires, which are just a few nanometers wide, are well-established because the wires are often used as "interconnects" in state-of-the-art electronics. Liu used a technique known as chemical vapor deposition (CVD) to cover the wires with a thin coating of carbon. The CVD technique is also used to grow sheets of single-atom-thick carbon called graphene on films of copper.

"When people make graphene, they usually want to study the graphene and they aren't very interested in the copper," Lou said. "It's just used a platform for making the graphene."

When Liu ran some electronic tests on his first few samples, the results were far from what he expected.

"We eventually found that a thin layer of copper oxide -- which is served as a dielectric layer -- was forming between the copper and the carbon," said Liu.

Upon examining other studies more closely, the team found that a few other scientists had made mention of oxidation occurring on the copper substrates during graphene production.

"It's fairly well-documented, but we couldn't find anyone who'd done a detailed examination of the electronic properties of such complex interfaces," Ajayan said.

The capacitance of the new nanocable is up to 143 microfarads per centimeter squared, better than the best previous results from microcapacitors.

Lou said it may be possible to build a large-scale energy-storage device by arranging millions of the tiny nanocables side by side in large arrays.

"The nanoscale cable might also be used as a transmission line for radio frequency signals at the nanoscale," Liu said. "This could be useful as a fundamental building block in micro- and nano-sized electromechanical systems like lab-on-a-chip devices."

The research was funded by the National Science Foundation, Rice University, the Office of Naval Research, the Welch Foundation, the Center for Exotic NanoCarbons at Shinshu University and the Japan Regional Innovation Strategy Program by the Excellence.

Co-authors include Lou, Ajayan, Liu, Yongjie Zhan, Gang Shi, Lulu Ma, Wei Gao and Robert Vajtai, all of Rice University; Pradeep Sharma and Mohamed Gharbi of the University of Houston; Simona Moldovan and Florian Banhart, both of Institut de Physique et Chimie des Matériaux in Strasbourg, France; Li Song of Shinshu University in Nagano, Japan; and Jiaqi Huang, formerly of Rice and currently at Tsinghua University in Beijing.

####

About Rice University
Located on a 300-acre forested campus in Houston, Rice University is consistently ranked among the nation's top 20 universities by U.S. News & World Report. Rice has highly respected schools of Architecture, Business, Continuing Studies, Engineering, Humanities, Music, Natural Sciences and Social Sciences and is known for its "unconventional wisdom." With 3,708 undergraduates and 2,374 graduate students, Rice's undergraduate student-to-faculty ratio is 6-to-1. Its residential college system builds close-knit communities and lifelong friendships, just one reason why Rice has been ranked No. 1 for best quality of life multiple times by the Princeton Review and No. 4 for "best value" among private universities by Kiplinger's Personal Finance. To read "What they're saying about Rice," go to www.rice.edu/nationalmedia/Rice.pdf.

For more information, please click here

Contacts:
David Ruth
713-348-6327


Jade Boyd
713-348-6778

Copyright © Rice University

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 Links

A copy of the Nature Communications paper is available at:

Related News Press

News and information

A big nano boost for solar cells: Kyoto University and Osaka Gas effort doubles current efficiencies January 21st, 2017

A toolkit for transformable materials: How to design materials with reprogrammable shape and function January 20th, 2017

Explaining how 2-D materials break at the atomic level January 20th, 2017

New research helps to meet the challenges of nanotechnology: Research helps to make the most of nanoscale catalytic effects for nanotechnology January 20th, 2017

Ultra-precise chip-scale sensor detects unprecedentedly small changes at the nanoscale January 20th, 2017

Lab-on-a-chip

New research helps to meet the challenges of nanotechnology: Research helps to make the most of nanoscale catalytic effects for nanotechnology January 20th, 2017

Ultra-precise chip-scale sensor detects unprecedentedly small changes at the nanoscale January 20th, 2017

New graphene-based system could help us see electrical signaling in heart and nerve cells: Berkeley-Stanford team creates a system to visualize faint electric fields December 19th, 2016

Graphene/ Graphite

Researchers design one of the strongest, lightest materials known: Porous, 3-D forms of graphene developed at MIT can be 10 times as strong as steel but much lighter January 7th, 2017

Nano-chimneys can cool circuits: Rice University scientists calculate tweaks to graphene would form phonon-friendly cones January 4th, 2017

First use of graphene to detect cancer cells: System able to detect activity level of single interfaced cell December 20th, 2016

NEMS

Leti Scientists Participating in Sessions on Med Tech, Automotive Technologies, MEMS, Si-photonics and Lithography at SEMICON Europa: Teams also Will Demonstrate Technology Advances in Telecom, Data Fusion, Energy, Silicon Photonics and 3D Integration October 18th, 2016

Integration of novel materials with silicon chips makes new 'smart' devices possible July 25th, 2016

Nano-photonics meets nano-mechanics: Controlling on-chip nano-optics by graphene nano-opto-mechanics January 22nd, 2016

Mechanical quanta see the light January 20th, 2016

Govt.-Legislation/Regulation/Funding/Policy

A toolkit for transformable materials: How to design materials with reprogrammable shape and function January 20th, 2017

'5-D protein fingerprinting' could give insights into Alzheimer's, Parkinson's January 19th, 2017

Strength of hair inspires new materials for body armor January 18th, 2017

Self-assembling particles brighten future of LED lighting January 18th, 2017

MEMS

Manufacturing platform makes intricate biocompatible micromachines January 7th, 2017

STMicroelectronics Peps Up Booming Social-Fitness Scene with Smart Motion Sensors for Better Accuracy, Longer Battery Life, and Faster Time to Market January 2nd, 2017

Movable microplatform floats on a sea of droplets: New technique offers precise, durable control over tiny mirrors or stages December 19th, 2016

Vesper a Finalist for Two ACE Awards: Ultimate Products and Innovator of the Year -- Industry’s first piezoelectric MEMS microphone and Vesper CTO Bobby Littrell recognized for prestigious electronics-industry awards November 10th, 2016

Discoveries

A big nano boost for solar cells: Kyoto University and Osaka Gas effort doubles current efficiencies January 21st, 2017

A toolkit for transformable materials: How to design materials with reprogrammable shape and function January 20th, 2017

Explaining how 2-D materials break at the atomic level January 20th, 2017

New research helps to meet the challenges of nanotechnology: Research helps to make the most of nanoscale catalytic effects for nanotechnology January 20th, 2017

Announcements

A big nano boost for solar cells: Kyoto University and Osaka Gas effort doubles current efficiencies January 21st, 2017

A toolkit for transformable materials: How to design materials with reprogrammable shape and function January 20th, 2017

New research helps to meet the challenges of nanotechnology: Research helps to make the most of nanoscale catalytic effects for nanotechnology January 20th, 2017

Ultra-precise chip-scale sensor detects unprecedentedly small changes at the nanoscale January 20th, 2017

Military

'5-D protein fingerprinting' could give insights into Alzheimer's, Parkinson's January 19th, 2017

Strength of hair inspires new materials for body armor January 18th, 2017

Self-assembling particles brighten future of LED lighting January 18th, 2017

Dressing a metal in various colors: DGIST research developed a technology to coat metal with several nanometers of semiconducting materials January 17th, 2017

Battery Technology/Capacitors/Generators/Piezoelectrics/Thermoelectrics/Energy storage

Chemists Cook up New Nanomaterial and Imaging Method: Nanomaterials can store all kinds of things, including energy, drugs and other cargo January 19th, 2017

Nanoscale view of energy storage January 16th, 2017

One step closer to reality: Devices that convert heat into electricity: Composite material yields 10 times -- or higher -- voltage output January 4th, 2017

STMicroelectronics Peps Up Booming Social-Fitness Scene with Smart Motion Sensors for Better Accuracy, Longer Battery Life, and Faster Time to Market January 2nd, 2017

Research partnerships

A big nano boost for solar cells: Kyoto University and Osaka Gas effort doubles current efficiencies January 21st, 2017

Chemists Cook up New Nanomaterial and Imaging Method: Nanomaterials can store all kinds of things, including energy, drugs and other cargo January 19th, 2017

Chemistry on the edge: Experiments at Berkeley Lab confirm that structural defects at the periphery are key in catalyst function January 13th, 2017

Recreating conditions inside stars with compact lasers: Scientists offer a new path to creating the extreme conditions found in stars, using ultra-short laser pulses irradiating nanowires January 12th, 2017

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