[17a-Z17-1~11] 9.4 Thermoelectric conversion

[17a-Z17-8] Development high-performance, p-type, Si-Ge-based thermoelectric materials

〇(B)Yuki Ohta¹, Iori Masaoka², Omprakash Muthusamy², Naoto Kubo², Masahiro Tahashi¹, Hideo Goto¹, Tsunehiro Takeuchi², Masaharu Matsunami² (1.Chubu Univ., 2.Toyota Tech Inst.)

Keywords:Thermoelectric material, Si-Ge system p-type thermoelectric material, Dimensionless figure of merit

High performance p-type thermoelectric materials are developed using Si-Ge based materials. We selected Ni and B as small amount impurity elements of electronic structure modification and doping, respectively. The nano-structure bulk samples were prepared using high-energy planetary-type ball milling and low-temperature & high-pressure sintering technique. We obtained a large power factor of 2.3 mWm^-1K^-2 at 1000 K for Si_0.62Ge_0.32B_0.03Ni_0.03, and rather small thermal conductivity ranging from 1.3 to 1.5mWm^-1K^-1 lead to a rathe large magnitude of ZT exceeding 1.5.