Featured Research

from universities, journals, and other organizations

Unzipped nanotubes unlock potential for batteries

Date:
June 13, 2013
Source:
Rice University
Summary:
Graphene nanoribbons and tin oxide make an effective anode for lithium ion batteries, as discovered in early tests.

Graphene nanoribbons split from nanotubes in a process created at Rice University are now being used to improve the performance of lithium ion batteries. The nanoribbons in a solution with tin oxide have more than double the capacity for lithium than standard graphene anodes in current commercial batteries.
Credit: Tour Group/Rice University

Researchers at Rice University have come up with a new way to boost the efficiency of the ubiquitous lithium ion (LI) battery by employing ribbons of graphene that start as carbon nanotubes.

Related Articles


Proof-of-concept anodes -- the part of the battery that stores lithium ions -- built with graphene nanoribbons (GNRs) and tin oxide showed an initial capacity better than the theoretical capacity of tin oxide alone, according to Rice chemist James Tour. After 50 charge-discharge cycles, the test units retained a capacity that was still more than double that of the graphite currently used for LI battery anodes.

The research appeared this week in the American Chemical Society journal ACS Nano­­.

Better batteries are greatly desired by everyone who carries a cellphone or computer or drives an electric car. The Rice team sees the potential for GNRs to contribute to their development.

Tour and his colleagues developed a method for unzipping nanotubes into GNRs, revealed in a 2009 cover story in Nature. Since then, the researchers have figured out how to make graphene nanoribbons in bulk and are moving toward commercial applications. One area ripe for improvement is the humble battery. In an increasingly mobile world, battery capacity is becoming a bottleneck that generally limits devices to less than a day's worth of use.

In the new experiments, the Rice lab mixed graphene nanoribbons and tin oxide particles about 10 nanometers wide in a slurry with a cellulose gum binder and a bit of water, spread it on a current collector and encased it in a button-style battery. GNRs are a single atom thick and thousands of times longer than they are wide. The GNRs not only separate and support the tin oxide but also help deliver lithium ions to the nanoparticles.

Lab tests showed initial charge capacities of more than 1,520 milliamp hours per gram (mAh/g). Over repeated charge-discharge cycles, the material settled into a solid 825 mAh/g. "It took about two months to go through 50 cycles," said lead author Jian Lin, a postdoctoral researcher at Rice, who believes it could handle many more without losing significant capacity.

GNRs could also help overcome a prime difficulty with LI battery development. Lithium ions tend to expand the material they inhabit, and the material contracts when they're pulled away. Over time, materials like silicon, which shows extraordinary capacity for lithium, break down and lose their ability to store ions. Other labs at Rice have made breakthroughs that help solve the expansion problem by breaking treated silicon into a powder, achieving great capacity and many cycles.

GNRs take a different approach by giving batteries a degree of flexibility, Tour said. "Graphene nanoribbons make a terrific framework that keeps the tin oxide nanoparticles dispersed and keeps them from fragmenting during cycling," he said. "Since the tin oxide particles are only a few nanometers in size and permitted to remain that way by being dispersed on GNR surfaces, the volume changes in the nanoparticles are not dramatic. GNRs also provide a lightweight, conductive framework, with their high aspect ratios and extreme thinness."

The researchers pointed out the work is a "starting point for exploring the composites made from GNRs and other transition metal oxides for lithium storage applications." Lin said the lab plans to build batteries with other metallic nanoparticles to test their cycling and storage capacities.

Co-authors of the paper are Rice graduate students Zhiwei Peng, Changsheng Xiang, Gedeng Ruan and Zheng Yan and Douglas Natelson, a Rice professor of physics and astronomy and of electrical and computer engineering. Tour is the T.T. and W.F. Chao Chair in Chemistry as well as a professor of mechanical engineering and materials science and of computer science at Rice.

Boeing, the Air Force Office of Scientific Research, Sandia National Laboratory and the Office of Naval Research supported the research.


Story Source:

The above story is based on materials provided by Rice University. Note: Materials may be edited for content and length.


Journal Reference:

  1. Jian Lin, Zhiwei Peng, Changsheng Xiang, Gedeng Ruan, Zheng Yan, Douglas Natelson, James M. Tour. Graphene Nanoribbon and Nanostructured SnO2Composite Anodes for Lithium Ion Batteries. ACS Nano, 2013; 130611113043009 DOI: 10.1021/nn4016899

Cite This Page:

Rice University. "Unzipped nanotubes unlock potential for batteries." ScienceDaily. ScienceDaily, 13 June 2013. <www.sciencedaily.com/releases/2013/06/130613153345.htm>.
Rice University. (2013, June 13). Unzipped nanotubes unlock potential for batteries. ScienceDaily. Retrieved November 26, 2014 from www.sciencedaily.com/releases/2013/06/130613153345.htm
Rice University. "Unzipped nanotubes unlock potential for batteries." ScienceDaily. www.sciencedaily.com/releases/2013/06/130613153345.htm (accessed November 26, 2014).

Share This


More From ScienceDaily



More Matter & Energy News

Wednesday, November 26, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

NASA's First 3-D Printer In Space Creates Its First Object

NASA's First 3-D Printer In Space Creates Its First Object

Newsy (Nov. 26, 2014) — The International Space Station is now using a proof-of-concept 3D printer to test additive printing in a weightless, isolated environment. Video provided by Newsy
Powered by NewsLook.com
Bolivian Recycling Initiative Turns Plastic Waste Into School Furniture

Bolivian Recycling Initiative Turns Plastic Waste Into School Furniture

Reuters - Innovations Video Online (Nov. 26, 2014) — Innovative recycling project in La Paz separates city waste and converts plastic garbage into school furniture made from 'plastiwood'. Tara Cleary reports. Video provided by Reuters
Powered by NewsLook.com
Who Will Failed Nuclear Talks Hurt Most?

Who Will Failed Nuclear Talks Hurt Most?

Reuters - Business Video Online (Nov. 25, 2014) — With no immediate prospect of sanctions relief for Iran, and no solid progress in negotiations with the West over the country's nuclear programme, Ciara Lee asks why talks have still not produced results and what a resolution would mean for both parties. Video provided by Reuters
Powered by NewsLook.com
Flying Enthusiast Converts Real-Life Aircraft Cockpit Into Simulator

Flying Enthusiast Converts Real-Life Aircraft Cockpit Into Simulator

Reuters - Innovations Video Online (Nov. 25, 2014) — A virtual flying enthusiast converts parts of a written-off Airbus aircraft into a working flight simulator in his northern Slovenian home. Jim Drury reports. Video provided by Reuters
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