Spark plasma sintering on the thermoelectric sulfide Ta2PdS6

We have prepared a dense ceramic sample of a novel thermoelectric sulfide Ta2PdS6 by means of spark plasma sintering technique under a uniaxial pressure. The Rietveld analyses of the X-ray diffraction patterns have clarified occurrence of weak preferred orientation in the sintering process. Resistivity, thermopower, and Hall resistivity measurements on the ceramic sample have indicated that it shows higher carrier density and lower carrier mobility than a single crystal. The inferior carrier mobility in the ceramic sample may partly come from increased point-defect and/or grain-boundary scattering, to which poor power factor is attributed.