Being astronauts during their missions hundreds of thousands or even millions of km away from Earth, it is not practical to gain energy in a conventional way such as exploiting coal or natural gas. Thus, new methods for harvesting energy need to be developed, methods possibly complementary to solar harvesting solution, to date possibly the safest and most effective in Space environments.
Among several possible scenarios, thermoelectric generators (TEGs) have been recognized as promising candidate for energy harvesting since they can recycle/harvest thermal energy using thermoelectric effect in a reliable, non-mechanical and sustainable way. However, the heat-electricity conversion efficiency has always been a serious limitation for this kind of device. In order to improve TEGs efficiency, in this project we suggest employing a metamaterials (MMs)-based approach, namely based on a new class of artificial materials, having the characteristic of carrying unique properties.
In particular, the highly customizable and readily tuneable features of MM technology is suitable for integration with thermoelectric materials/devices to boost conversion efficiency in a nonconventional way. Furthermore, the final product is expected to be readily scalable and adaptable for Space applications.
In general, the integration of MMs with a TEG can be envisioned following two routes (see Figure):
- Photonic MMs (PtMMs) can efficiently harvest the heat associated to the incoming photons through an effective photon-phonon conversion (heat generation, perfect absorber), therefore making this category of plasmonic MMs a perfect heat source to be coupled to TEG;
- Phononic MM (PnMMs) will be designed and fabricated following the vision of a structure capable to manipulate the phonon transportation inside the material so that low thermal conductivity and high electric conductivity can be achieved, conditions defining a good thermoelectric material.
