Machines and electronic devices often generate waste heat that is difficult to utilize. If this could be used to generate electricity, it would offer a clean and sustainable approach to energy generation, ideal for energy-saving electronic applications.
Thermoelectric generators, i.e. machines that generate electricity by using temperature differences, already exist, but the efficiency of thermoelectric conversion is low and they have to be cooled down to temperatures just above absolute zero. However, efficiency can be significantly improved by exploiting quantum effects.
EMPA researchers are using graphene nanoribbons for this purpose, which are still stable even at significantly higher temperatures. The aim is to integrate them into a quantum heat engine and make it run at room temperature. As the quantum dots are only a few nanometers in size, special manufacturing techniques must be developed for the electrical contacting. Customized measuring systems are also needed to determine the efficiency of the energy conversion. If all goes well, Perrin could develop a tiny heat engine on a chip in the next few years. This could not only generate electricity from waste heat, but would also be suitable for efficient cooling by reversing the operating principle.
