| Abstract Scope |
Interest in metallic thermoelectrics is experiencing a renaissance lately, partly due to the discovery of the exceptionally good thermoelectric properties of the Ni-Au alloy [Garmroudi et al, Science
Advances 2023], which has a record-high power factor of 30 mWm-1K-2, superior to any known bulk material, and a ZT of ~0.5, exceeding any current metallic systems. These exceptional properties originate from the resonant scattering of electrons, similar to what occurs in semiconducting thermoelectrics containing resonant impurities (PbTe:Tl, SnTe:In), which also have exceptionally good thermoelectric properties.
We present the results of electronic structure and transport properties calculations (KKR-CPA method, Kubo formalism) for Ni-Au. We explain the source of its exceptionally good thermoelectric properties, why it is a better thermoelectric material than the Cu-Ni alloy (constantan), which has been in use for decades, and contrast the resonant effects in metallic alloys and semiconductors, showing their similarities and differences. |