Navigation Links
Rice scientists build battery in a nanowire
Date:7/29/2011

The world at large runs on lithium ion batteries. New research at Rice University shows that tiny worlds may soon do the same.

The Rice lab of Professor Pulickel Ajayan has packed an entire lithium ion energy storage device into a single nanowire, as reported this month in the American Chemical Society journal Nano Letters. The researchers believe their creation is as small as such devices can possibly get, and could be valuable as a rechargeable power source for new generations of nanoelectronics.

In their paper, researchers described testing two versions of their battery/supercapacitor hybrid. The first is a sandwich with nickel/tin anode, polyethylene oxide (PEO) electrolyte and polyaniline cathode layers; it was built as proof that lithium ions would move efficiently through the anode to the electrolyte and then to the supercapacitor-like cathode, which stores the ions in bulk and gives the device the ability to charge and discharge quickly.

The second packs the same capabilities into a single nanowire. The researchers built centimeter-scale arrays containing thousands of nanowire devices, each about 150 nanometers wide. A nanometer is a billionth of a meter, thousands of times smaller than a human hair.

Ajayan's team has been inching toward single-nanowire devices for years. The researchers first reported the creation of three-dimensional nanobatteries last December. In that project, they encased vertical arrays of nickel-tin nanowires in PMMA, a widely used polymer best known as Plexiglas, which served as an electrolyte and insulator. They grew the nanowires via electrodeposition in an anodized alumina template atop a copper substrate. They widened the template's pores with a simple chemical etching technique that created a gap between the wires and the alumina, and then drop-coated PMMA to encase the wires in a smooth, consistent sheath. A chemical wash removed the template and left a forest of electrolyte-encased nanowires.

In that battery, the encased nickel-tin was the anode, but the cathode had to be attached on the outside.

The new process tucks the cathode inside the nanowires, said Ajayan, a professor of mechanical engineering and materials science. In this feat of nanoengineering, the researchers used PEO as the gel-like electrolyte that stores lithium ions and also serves as an electrical insulator between nanowires in an array.

After much trial and error, they settled on an easily synthesized polymer known as polyaniline (PANI) as their cathode. Drop-coating the widened alumina pores with PEO coats the insides, encases the anodes and leaves tubes at the top into which PANI cathodes could also be drop-coated. An aluminum current collector placed on top of the array completes the circuit.

"The idea here is to fabricate nanowire energy storage devices with ultrathin separation between the electrodes," said Arava Leela Mohana Reddy, a research scientist at Rice and co-author of the paper. "This affects the electrochemical behavior of the device. Our devices could be a very useful tool to probe nanoscale phenomenon."

The team's experimental batteries are about 50 microns tall -- about the diameter of a human hair and almost invisible when viewed edge-on, Reddy said. Theoretically, the nanowire energy storage devices can be as long and wide as the templates allow, which makes them scalable.

The nanowire devices show good capacity; the researchers are fine-tuning the materials to increase their ability to repeatedly charge and discharge, which now drops off after a about 20 cycles.

"There's a lot to be done to optimize the devices in terms of performance," said the paper's lead author, Sanketh Gowda, a chemical engineering graduate student at Rice. "Optimization of the polymer separator and its thickness and an exploration of different electrode systems could lead to improvements."

Rice graduate student Xiaobo Zhan is a co-author of the paper.


'/>"/>

Contact: David Ruth
druth@rice.edu
713-348-6327
Rice University
Source:Eurekalert

Related biology technology :

1. Comprendia and New England Biolabs Connect Epigenetics Scientists with New Social Media Application
2. Scientists shed light on the private lives of electrons
3. Scientists hope to get glimpse of adolescent universe from revolutionary instrument-on-a-chip
4. Berkeley scientists pioneer nanoscale nuclear materials testing capability
5. N.C. Scientists Plant Plants to be Manufacturing Plants
6. Northern Illinois University scientists find simple way to produce graphene
7. 22 of Americas Most Promising Scientists Selected as 2011 Pew Scholars in the Biomedical Sciences
8. Scientists Launch Vaccine Research Foundation
9. Scientists Discover Gene Regulator That Helps Hearts Through Exercise
10. New findings by UCR scientists hold big promise for fight against mosquito-borne diseases
11. Led by Advances in Chemical Synthesis, Scripps Research Scientists Discover that a Rare Natural Product Has Potent Pain-Killing Properties
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:6/26/2017)... ... , ... The Workgroup for Electronic Data Interchange (WEDI) , the nation’s ... information exchange and a statutory advisor to the U.S. Department of Health and Human ... the National Coordinator for Health Information Technology, will deliver the keynote at its 2017 ...
(Date:6/23/2017)... ... June 23, 2017 , ... RURO, Inc., ... version of LimitLIS®, its rapidly growing Laboratory Information System. , LimitLIS® version 3 ... installation integrity, and provide more customization options. Each of these has been “under ...
(Date:6/23/2017)... ... 2017 , ... The Academy of Model Aeronautics (AMA), the ... (UAA), the unifying voice for collegiate aviation education, are launching a joint UAS ... success through a STEM-based education platform. , Much like the program currently available ...
(Date:6/22/2017)... ... ... Building on the success of the inaugural RAADfest last year, RAADfest 2017 ... in radical life extension. RAADfest combines cutting edge science presented for a lay audience, ... making it the largest most comprehensive and inclusive super longevity event in the world. ...
Breaking Biology Technology:
(Date:3/23/2017)... Research and Markets has announced the addition ... - Industry Forecast to 2025" report to their offering. ... The Global Vehicle ... around 8.8% over the next decade to reach approximately $14.21 billion ... estimates and forecasts for all the given segments on global as ...
(Date:3/22/2017)... 21, 2017 Vigilant Solutions , a ... enforcement agencies, announced today the appointment of retired FBI ... public safety business development. Mr. Sheridan brings ... including a focus on the aviation transportation sector, to ... position, Mr. Sheridan served as the Aviation Liaison Agent ...
(Date:3/16/2017)... , March 16, 2017 CeBIT 2017 - Against identity fraud ... Continue Reading ... Used combined in one project, multi-biometric solutions provide a ... Used combined ... ...
Breaking Biology News(10 mins):