Thermoelectric properties of partly Sb- and Zn-substituted Ba8Ga16Ge30 clathrates
Artikel i vetenskaplig tidskrift, 2010

The effects on the thermoelectric properties of n-Ba8Ga16Ge30 when substituting small amounts of the Ga or Ge with Sb or Zn have been investigated. A number of syntheses were prepared in quaternary systems of Ba8Ga16Ge30 substituted with either Sb or Zn but only three samples were found to yield single phase products with nominal compositions of Ba8Ga15Sb1Ge30, Ba8Ga15Zn1Ge30 and Ba8Ga16Ge28Zn2, respectively. When Ge was substituted for Zn the resulting sample remained n-type and an increase in thermopower and a decrease in thermal conductivity were achieved. These positive effects were accompanied with an increased electrical resistivity and thus the ZT was only somewhat improved up to about 400 °C. When substituting Ga with either Sb or Zn samples remained n-type but showed decreased thermopower and increased electrical resistivity and thermal conductivity. It is thus concluded that substitution of Ga with Zn or Sb is detrimental for the thermoelectric properties of Ba8Ga16Ge30, whereas substitution of Ge with Zn appears a potent method for improving its performance.

Författare

Daniel Cederkrantz

Chalmers, Kemi- och bioteknik, Teknisk ytkemi

Mats Nygren

Anders Palmqvist

Chalmers, Kemi- och bioteknik, Teknisk ytkemi

Journal of Applied Physics

0021-8979 (ISSN) 1089-7550 (eISSN)

Vol. 108 113711-

Ämneskategorier

Oorganisk kemi

Den kondenserade materiens fysik

Drivkrafter

Hållbar utveckling

Styrkeområden

Nanovetenskap och nanoteknik

Energi

Materialvetenskap

Fundament

Grundläggande vetenskaper

DOI

10.1063/1.3518043