Thermoelectric Figure of Merit, ZT, of Single Crystal Pentatellurides (MTe5-XSex: M = Hf, Zr and x = 0, 0.25)


The thermoelectric figure of merit, ZT = α2σT/λ, has been measured for pentatelluride single crystals of HfTe5, ZrTe5, as well as Se substituted pentatellurides. The parent materials, HfTe5 and ZrTe5, exhibit relatively large p- and n- type thermopower, ⋎a⋎ > 125 μV/K, and low resistivity, ρ ≤ 1 mΩ•cm. These values lead to a large power factor (α2σT) which is substantially increased with proper Se substitution on the Te sites. The thermal conductivity of these needle-like crystals has also been measured as a function of temperature from 10 K ≤ T ≤ 300 K. The room temperature figure of merit for these materials varies from ZT “0.1 for the parent materials to ZT ≈ 0.25 for Se substituted samples. These results as well as experimental procedures will be presented and discussed.

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Littleton, R.T., Tritt, T.M., Zawilski, B. et al. Thermoelectric Figure of Merit, ZT, of Single Crystal Pentatellurides (MTe5-XSex: M = Hf, Zr and x = 0, 0.25). MRS Online Proceedings Library 626, 31 (2000).

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