Synthesis and electrical transport properties of p-type Ba8Ga16CdxGe30−x type-I clathrates

Author

Deng, Shukang ; Tang, Xinfeng ; Li, Han ; Yan, Yonggao ; Zhang, Qingjie

Author_Institution

State Key Lab. of Adv. Technol. for Mater. Synthesis & Process., Wuhan Univ. of Technol., Wuhan

fYear

2007

fDate

3-7 June 2007

Firstpage

230

Lastpage

233

Abstract

P-type Ba₈Ga₁₆Cd_xGe_30-x (x=0.95, 1.00, 1.05, 1.10) type-I clathrates with different Cd contents were synthesized by combining melt method with spark plasma sintering (SPS). The effects of Cd content on electrical transport properties have been investigated. The results show that all samples exhibit p-type conduction. The Seebeck coefficient alpha and room temperature carrier mobility mu_H decrease with the increasing Cd content. The electrical conductivity sigma and the room temperature carrier concentration N_p increase with the increase of Cd content. In the low temperature range (T<150 K), the carrier scattering mechanism is mainly ionized impurity mechanism, and gradually changes to an acoustical mechanism with the rising temperature. The maximum power factor value of 0.35times10^-3 Wm^-1K^-2 is obtained at 550 K for Ba₈Ga₁₆Cd_1.00Ge_29.00.

Keywords

Seebeck effect; barium alloys; cadmium alloys; carrier density; carrier mobility; electrical conductivity; gallium alloys; germanium alloys; sintering; Ba₈Ga₁₆Cd_xGe_30-x; Seebeck coefficient; acoustical mechanism; carrier scattering mechanism; electrical conductivity; electrical transport properties; ionized impurity mechanism; melt method; p-type conduction; room temperature carrier concentration; room temperature carrier mobility; spark plasma sintering; temperature 293 K to 298 K; temperature 550 K; type-I clathrates; Conducting materials; Inorganic materials; Plasma properties; Plasma temperature; Reactive power; Sparks; Temperature distribution; Thermal conductivity; Thermoelectricity; X-ray scattering; electrical transport property; p-type conduction; type-I clathrate;

fLanguage

English

Publisher

ieee

Conference_Titel

Thermoelectrics, 2007. ICT 2007. 26th International Conference on

Conference_Location

Jeju Island

ISSN

1094-2734

Print_ISBN

978-1-4244-2262-3

Electronic_ISBN

1094-2734

Type

conf

DOI

10.1109/ICT.2007.4569466

Filename

4569466