Efficiently synthesized n-type CoSb₃ thermoelectric alloys under TGZM effect

Skutterudite compounds, the structure of “phonon glass electron crystal” (PGEC), possess excellent thermoelectric properties. Here, temperature gradient zone melting combined with hot pressing technique (TGZM-HP) was employed to synthesize n-type skutterudite Ce_xNi_1.5Co_2.5Sb₁₂ thermoelectric material. By doping element Ce, the carrier concentration of the alloy was optimized efficiently and the total thermal conductivity declined. For the TGZM-HP Ce_0.6Ni_1.5Co_2.5Sb₁₂ alloy, the power factor PF reaches to 1350 μW/(mK²), and the lattice thermal conductivity is dropped to 1.62 Wm⁻¹K¹ at 850 K, corresponding to an improved figure of merit ZT of 0.45. Importantly, compared with the traditional synthesis methods, this technique can precisely control the formation of thermometric phase and the preparation time is reduced remarkably.