Title :
Effect of carrier doping on the thermal conductivity of MNiSn based half-Heusler alloy
Author :
Muta, Hiroaki ; Kanemitsu, Takanori ; Kurosaki, Ken ; Yamanaka, Shinsuke
Author_Institution :
Div. of Sustainable Energy & Environ. Eng., Osaka Univ.
Abstract :
Thermal conductivity of doped MNiSn (M = Ti, Zr) half-Heusler alloys has been investigated from room temperature to 1000 K. Nonnegligible increase of thermal conductivity was observed for all the samples at high temperature. The temperature dependence appeared to the corresponding to the change of electrical properties and carrier concentration, indicating that the electron-hole pair generation caused the increase of thermal conductivity. The effect, called ambipolar diffusion effect, depends on a bandgap and a ratio of electron and hole conduction. In this study the bandgap was determined from electrical conductivity of yttrium doped of ZrNiSn and the temperature dependence of the ambipolar diffusion effect was quantitatively investigated
Keywords :
carrier density; diffusion; doping profiles; electron mobility; energy gap; hole mobility; nickel alloys; thermal conductivity; tin alloys; titanium alloys; yttrium alloys; zirconium alloys; 293 to 1000 K; TiNiSn; ZrNiSn:Y; ambipolar diffusion effect; bandgap; carrier concentration; carrier doping effects; doped half-Heusler alloys; electrical properties; electron conduction; electron-hole pair generation; half Heusler alloy thermal conductivity; hole conduction; yttrium doped ZrNiSn; Atmospheric measurements; Doping; Photonic band gap; Plasma temperature; Temperature dependence; Temperature measurement; Thermal conductivity; Thermal engineering; Thermoelectricity; Zirconium;
Conference_Titel :
Thermoelectrics, 2006. ICT '06. 25th International Conference on
Conference_Location :
Vienna
Print_ISBN :
1-4244-0811-3
Electronic_ISBN :
1094-2734
DOI :
10.1109/ICT.2006.331295
