| Title |
Optimization of High Temperature Thermoelectric Properties of TiNiSn-Based Half-Heusler Compounds |
| Authors |
김성웅(Sung Wng Kim); 홍성길(Sung Kil Hong); 최답천(Dap Chun Choi); (Yoshisato Kimura); (Yoshinao Mishima) |
| ISSN |
1738-8228(ISSN), 2288-8241(eISSN) |
| Keywords |
TiNiSn half-Heusler; Powder metallurgy; Thermoelectric properties; Seebeck coefficient; Electrical resistivity; Thermal conductivity; Dimensionless figure of merit |
| Abstract |
The effect of Hf alloying on Ti site, and Sb doping on Sn site for the optimization of high temperature thermoelectric properties of TiNiSn-based compounds was studied. Also, to achieve a low thermal conductivity, a powder metallurgy technique is used for the fabrication of the compounds. It was found that Hf alloying on Ti site reduced the thermal conductivity significantly to a low value of 3.8 W/mK at room temperature. Also, Sb doping on Sn site led to a remarkable enhancement of power factor of 4.1 mW/mK2. Further reduction of thermal conductivity was achieved in hot pressed samples. In hot pressed Ti(0.95)Hf(0.05)NiSn(0.99)Sb(0.01) sample, the dimensionless figure of merit, ZT reaches 0.78 at 770 K. |