A team of scientists at MIT has discovered a previously unknown phenomenon that can cause powerful waves of energy to shoot through minuscule wires known as carbon nanotubes, a discovery that could lead to a new way of producing electricity.
The phenomenon, described as thermopower waves, “opens up a new area of energy research, which is rare,” said Michael Strano, MIT’s Charles and Hilda Roddey Associate Professor of Chemical Engineering, who was the senior author of a paper describing the new findings.
Like a collection of flotsam propelled along the surface by waves traveling across the ocean, it turns out that a thermal wave — a moving pulse of heat — traveling along a microscopic wire can drive electrons along, creating an electrical current. The key ingredient in the recipe is carbon nanotubes — submicroscopic hollow tubes made of a chicken-wire-like lattice of carbon atoms.
In the new experiments, each of these electrically and thermally conductive nanotubes was coated with a layer of a highly reactive fuel that can produce heat by decomposing.
This fuel was then ignited at one end of the nanotube using either a laser beam or a high-voltage spark, and the result was a fast-moving thermal wave travelling along the length of the carbon nanotube like a flame speeding along the length of a lit fuse.
According to Strano, in the group’s initial experiments, when they wired up the carbon nanotubes with their fuel coating in order to study the reaction, “lo and behold, we were really surprised by the size of the resulting voltage peak” that propagated along the wire.
A team of scientists has discovered magnetic waves that fluctuate when exposed to certain conditions in a superconducting material.
