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Thermoelectric properties of the layered Pd oxide R_2PdO_4 (R = La, Nd, Sm and Gd)

S. Shibasaki·I. Terasaki
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Abstract

We prepared polycrystalline samples of R$_2$PdO$_4$ (R = La, Nd, Sm and Gd) using a NaCl-flux technique. The measured resistivity is of the order of 10$^3-10^4$ $Ω$cm at room temperature, which is two orders of magnitude smaller than the values reported so far. We further studied the substitution effects of Ce for Nd in Nd$_{1.9}$Ce$_{0.1}$PdO$_4$, where the substituted Ce decreases the resistivity and the magnitude of the thermopower. The activation energy gap of 70-80 meV and the effective mass of 15 evaluated from the measured data are suitable for thermoelectric materials, but the mobility of 10$^{-6}$ cm$^2$/Vs is much lower than a typical value of 1-10 cm$^2$/Vs for other thermoelectric oxides.

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S. Shibasaki, I. Terasaki. 2005-11-10. Thermoelectric properties of the layered Pd oxide R_2PdO_4 (R = La, Nd, Sm and Gd). https://doi.org/10.1143/jpsj.75.024705

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