A Louisiana Tech University professor, dr. Long Que, has designed and prototyped a composite material that converts heat into electricity by using simple physical mechanisms found in piezoelectric materials and carbon nanotubes.
The devices Que invented will be able to recover part of the energy gadgets lose through heat. His technology uses a cantilever made out of a piezoelectric material coated with a carbon nanotube film on one side. The piezoelectric material can convert even the slightest bends into electricity, while the carbon nanotubes have the role of absorbing heat.
When heat enters the carbon nanotubes, it causes the piezoelectric cantilever to bend back and forth and thus harvest the energy. “The greatest significance of this work is that it offers us a new option to continuously harvest both solar and thermal energy on a single chip, given the self-reciprocating characteristics of the device upon exposure to light and/or thermal radiation,” said Que. “This characteristic might enable us to make perpetual micro/nano devices and micro/nanosystems, and could significantly impact the wireless sensory network.”
“It is truly a hybrid energy-harvesting technology,” Que said. “My lab has been optimizing and making great progress on this technology in an effort to enhance its efficiency and overall performance, indicating great promise for this technology.”
Dr. Que’s work could easily be implemented in low-current applications such as biomedical devices and sensors. Where natural conditions are harsh and the energy needs to be consumed efficiently, such a thermoelectric device could find its place. If ported to a higher scale, thermoelectric devices could also recover the energy lost through heat in electric cars, increasing their efficiency and making the electric systems act more like a superconductor, where electricity isn’t lost through thermal effects.