Structure and thermoelectric performance of Ti-filled and Te-doped skutterudite TixCo4Sb11.5Te0.5 bulks fabricated by combination of microwave synthesis and spark plasma sintering

In the present wok, a series of Ti-filled and Te-doped skutterudite compounds TixCo4Sb11.5Te0.5 (x = 0.2, 0.3, 0.5) were successful fabricated by combination of microwave synthesis and spark plasma sintering technique. The microstructure and thermoelectric properties of TixCo4Sb11.5Te0.5 bulks have been investigated systematically. The experimental results show that nearly single phase skutterudite were obtained by 5 min microwave synthesis. The Ti0.3Co4Sb11.5Te0.5 bulk has smallest and uniform grain size of about 2 μm. The influences of Ti concentration on thermoelectric properties were discussed. A highest ZT of 0.60 for Ti0.3Co4Sb11.5Te0.5 was achieved at 773 K along with a total thermal conductivity of 3.72 W m−1 K−1, one might obtain higher values at a higher temperature.