Thermoelectric Properties of Sn-Containing Mg 2 Si Nanostructures

Hilal Balout (1) , Pascal Boulet (2) , Marie-Christine Record (3, 2)

1 MADIREL - Matériaux divisés, interfaces, réactivité, électrochimie
2 AMU - Aix Marseille Université
3 IM2NP - Institut des Matériaux, de Microélectronique et des Nanosciences de Provence

The thermoelectric performance of Mg2Si- containing nanomaterials are predicted based on density- functional and Boltzmann’s transport theories. The investigated materials are Mg2Si1−xSnx thin films with x = 0.125 and x = 0.625, and (Mg2Si)1−x (Mg2Sn)x (x = 0.4 and x = 0.6) in the form of either superlattices or assembled nanosticks. The calculated properties (Seebeck coefficient S, electrical con- ductivity σ, and power factor S2σ) are compared with those of bulk Mg2Si1−xSnx. It is shown that the thin films outperform the bulk materials at low temperature (350 K) as they exhibit a higher Seebeck coefficient and comparable electrical conductiv- ity. A low electrical conductivity at 900 K is responsible for the counter-performance of the films. Superlattices are attractive structures as p-doped materials at both low charge carrier concentration/high temperature and high charge carrier concentration/high temperature. The assembled nanosticks are interesting materials at low carrier concentration/low temperature only.

Domains: Chemical Sciences; Material chemistry; Chemical Sciences; Theoretical and/or physical chemistry

Hilal Balout, Pascal Boulet, Marie-Christine Record. Thermoelectric Properties of Sn-Containing Mg 2 Si Nanostructures. Journal of Physical Chemistry C, 2015, 119 (31), pp.17515 - 17521. ⟨10.1021/acs.jpcc.5b03351⟩. ⟨hal-01483322⟩