2001/08/29 by I. Terasaki
Physics and Astronomy · #cond-mat.str-el #cond-mat.mtrl-sci
published as Proc. of the 19th International Conference on Thermoelectrics (ICT 2000), p.182 · PDF only
arxiv created 2001/08/29 · arxiv updated 2009/11/30
We prepared polycrystalline samples of NaCo2-xMxO4 substituted for the Co site by other 3d or 4d elements (M=Mn,Cu, Zn, Ru, Rh, and Pd). While some of the elements (M=Mn,Ru and Rh) act as a strong scatterer to give rise to a rapid increase in resistivity, the others (M=Cu, Zn and Pd) do not deteriorate the electric conduction of the host. Most unusually, the Cu substitution significantly enhances the thermopower, which increases the figure of merit by several times at 100 K.