n- and p- Type behaviour of the gold-substituted type-I clathrate, Ba8AuxSi46-x (x = 5.4 and 5.9)
Language
en
Article de revue
This item was published in
Comptes Rendus. Chimie. 2005, vol. 8, n° 1, p. 39-46
Académie des sciences (Paris)
English Abstract
Two samples of the gold-substituted silicon clathrate, Ba8AuxSi46–x, have been synthesized from the elements at high temperature, one without subsequent treatment (so-called AG for as-grown) and the other after annealing ...Read more >
Two samples of the gold-substituted silicon clathrate, Ba8AuxSi46–x, have been synthesized from the elements at high temperature, one without subsequent treatment (so-called AG for as-grown) and the other after annealing in a silica tube (so-called A for annealed). A structure analysis on single crystal of both samples shows that the x Au content for the AG and A sample is 5.4 and 5.9, respectively. Both samples have been characterized by Seebeck coefficient and electrical conductivity measurements, as well as by 29Si MAS NMR spectroscopy. The AG sample is an n-type semi conductor close to a metal, whereas the A one exhibits a p-type metallic behaviour. The NMR spectra are consistent with a high contribution to the conductivity of the Si(3s) orbitals at the Fermi levelRead less <
English Keywords
Thermoelectrics
Clathrates
Structures
Seebeck
Conductivity
NMR
Origin
Hal imported