Researchers have found a way to improve thermoelectric materials.
The finding could improve solar panels, lead to a more energy-efficient method of cooling, and even create a device that could convert excess heat generated by power plants into electricity, a University of Colorado at Boulder news release reported.
The new technique builds an array of tiny pillars on top of thermoelectric material.
The thermoelectric effect is "the ability to generate an electric current from a temperature difference between one side of a material and the other," the news release reported. When electrical voltage is applied to the thermoelectric material it can cause one side to heat up while the other stays cool.
Devices that use thermoelectric material usually turn heat into electricity or cool instruments using electricity. The problem is when electricity is allowed through the device heat is as well. When a temperature difference is created the unwelcome heat dissipates the difference and weakens the current.
"Until 20 years ago, people were looking at the chemistry of the materials," Mahmoud Hussein, an assistant professor of aerospace engineering sciences said in the news release. "And then nanotechnology came into the picture and allowed researchers to engineer the materials for the properties they wanted."
Researchers created barriers that lessened heat flow more so than electricity using nanotechnology; this system still impeded electricity.
This new system involves tiny nanoscale pillars built on top of a thermodynamic material such as silicon.
"Heat is carried through the material as a series of vibrations, known as phonons," the news release reported. The researchers believe the vibrations effectively slowed down the heat flow without disturbing the electric current.
"If we can improve thermoelectric energy conversion significantly, there will be all kinds of important practical applications," Hussein said. These include recapturing the waste heat emitted by different types of equipment -- from laptops to cars to power plants -- and turning that heat into electricity. Better thermoelectrics also could vastly improve the efficiency of solar panels and refrigeration devices."
