Nanotube thermopower: Efforts to store energy in carbon nanotubes described

Oct 20, 2010

When weighing options for energy storage, different factors can be important, such as energy density or power density, depending on the circumstances. Generally batteries -- which store energy by separating chemicals -- are better for delivering lots of energy, while capacitors -- which store energy by separating electrical charges -- are better for delivering lots of power (energy per time). It would be nice, of course, to have both.

Today at the AVS 57th International Symposium & Exhibition, which takes place this week at the Albuquerque Convention Center in New Mexico, Michael Strano and his colleagues at MIT will report on efforts to store energy in thin carbon nanotubes by adding fuel along the length of the tube, chemical energy, which can later be turned into electricity by heating one end of the nanotubes. This thermopower process works as follows: the heat sets up a chain reaction, and a wave of conversion travels down the nanotubes at a speed of about 10 m/s.

"Carbon nanotubes continue to teach us new things -- thermopower waves as a first discovery open a new space of power generation and reactive wave physics," Strano says.

A typical lithium ion battery has a power density of 1 kW/kg. Although the MIT researchers have yet to scale up their nanotube materials, they obtain discharge pulses with power densities around 7 kW/kg.

Strano will also be reporting new results on experiments exploiting carbon nanopores of unprecedented size, 1.7 nm in diameter and 500 microns long.

"Carbon nanopores," he says, "allow us to trap and detect single molecules and count them one by one," the first time this has been done. And this was at room temperature.

The single molecules under study can move across the nanotubes one at a time in a process called coherence resonance. "This has never been shown before for any inorganic system to date," says Strano, "but it underpins the workings of biological ion channels."

Explore further: Understanding the source of extra-large capacities in promising Li-ion battery electrodes

More information: The presentation, "New Concepts in Molecular and Energy Transport Within Carbon Nanotubes: Thermopower Waves and Stochastically Resonant Ion Channels" is at 4:40 p.m. on Tuesday, October 19, 2010. ABSTRACT:… PaperNumber=NS-TuA-9

Provided by American Institute of Physics

3 /5 (1 vote)
add to favorites email to friend print save as pdf

Related Stories

Researchers develop a way to funnel solar energy

Sep 12, 2010

( -- Using carbon nanotubes (hollow tubes of carbon atoms), MIT chemical engineers have found a way to concentrate solar energy 100 times more than a regular photovoltaic cell. Such nanotubes could ...

Recommended for you

Tough foam from tiny sheets

3 hours ago

Tough, ultralight foam of atom-thick sheets can be made to any size and shape through a chemical process invented at Rice University.

Graphene surfaces on photonic racetracks

Jul 28, 2014

In an article published in Optics Express, scientists from The University of Manchester describe how graphene can be wrapped around a silicon wire, or waveguide, and modify the transmission of light through it.

Simulating the invisible

Jul 28, 2014

Panagiotis Grammatikopoulos in the OIST Nanoparticles by Design Unit simulates the interactions of particles that are too small to see, and too complicated to visualize. In order to study the particles' behavior, he uses ...

Building 'invisible' materials with light

Jul 28, 2014

A new method of building materials using light, developed by researchers at the University of Cambridge, could one day enable technologies that are often considered the realm of science fiction, such as invisibility ...

User comments : 0