An international team of scientists hailing from Ohio State University, North Carolina State University and the Chinese Academy of Sciences has found a way to capture heat and transform it into electricity using magnet particles.
The research, which was published in journal Science Advances, has the potential to create more efficient ways to generate heat from car exhausts, industrial processes and even space missions.
Paramagnets can capture heat, turn it into electricity
The researchers focused their work on paramagnons, which are tiny bits that carry magnetic flux but are not magnets themselves. Magnets, when heated, lose their magnetic forces and become paramagnetic. At that stage, they cant be used to collect energy according to conventional wisdom.
But the scientists turned that on its head, finding that once a paramagnet is heated up it can capture heat and turn it into electricity.
"The conventional wisdom was once that, if you have a paramagnet and you heat it up, nothing happens," said study co-author Joseph Heremans, professor of mechanical and aerospace engineering and Ohio Eminent Scholar in Nanotechnology at The Ohio State University in a press release announcing the research findings. "And we found that that is not true. What we found is a new way of designing thermoelectric semiconductors--materials that convert heat to electricity. Conventional thermoelectrics that we've had over the last 20 years or so are too inefficient and give us too little energy, so they are not really in widespread use. This changes that understanding."
More energy can be made from heat
There are limitations to the researchers' findings. They discovered that paramagnons can push electrons but only for a billionth of a millionth of a second. Still, the researchers said its enough to make paramagnets energy harvesters. "Because of this discovery, we should be able to make more electrical energy out of heat than we do today," said Heremans. "It's something that, until now, nobody thought was possible."