Thermoelectric properties of nanocomposite heavy fermion CeCu6

We report on the thermoelectric performance of the heavy fermion compound CeCu6 nanocomposite samples. Measurements of Seebeck coefficient, electrical resistivity and thermal conductivity are presented over the temperature range 5 < T < 350 K. The dimensionless figure-of-merit (ZT) was optimized by varying the sample hot-pressing temperature. Thermal conductivity measurements show that the lowest hot pressing temperature (450 °C) produces the lowest thermal conductivity. Electrical resistivity is strongly influenced by hot pressing temperature and drops by a factor of ∼3.4 as the hot pressing temperature is lowered from 800 to 450 °C. Seebeck coefficient shows a slight increase over other samples when hot pressed at 800 °C. Our ZT calculations show a broad peak with a maximum value of 0.024 at ∼60 K for the sample hot pressed at 800 °C.