The study comes from Ohio State University and here researchers have developed a process to capture heat and then to convert this it into electricity. The experiments could lead to processes which create more efficient energy generation, drawing heat from a range of activities like running car exhausts to interplanetary space probes. However, the primary application could be from capturing heat from a range of industrial processes.
The new process is based on minute particles termed paramagnons. These are quasipaticles in magnetic materials which are in their high temperature, disordered (paramagnetic) phase. In crude terms, they are tiny particles that are not quite magnets, but which possess some magnetic flux.
As paramagnons are heated (undergoing ‘spin’) this generates a form of energy termed ‘magnon-drag thermoelectricity’. This is a process that could potentially be used to collect energy at room temperature.
From this effect, the scientists have been able to design thermoelectric semiconductors, which are materials that can convert heat to electricity. This is possible because paramagnons have been shown to be able to push electrons, for just a billionth of a millionth of a second, which remarkably is sufficient to enable paramagnets to function as powerful energy-harvesters.
Commenting on the implications of the research, principal scientist Joseph Heremans states: “Because of this discovery, we should be able to make more electrical energy out of heat than we do today. It’s something that, until now, nobody thought was possible.”
The development has been reported to the journal Science Advances. The research paper is titled “Paramagnon drag in high thermoelectric figure of merit Li-doped MnTe.”
