The Effect Of Eu Substitution On Thermoelectric Properties Of Srti0.8nb0.2o3

Herein we demonstrate that Eu2+ substitution of SrTi0.8Nb0.2O3 is effective in reducing the thermal conductivity, with no reduction in the thermoelectric power factor (S-2 sigma; S, Seebeck coefficient; sigma, electrical conductivity). We prepared cubic (Sr,Eu)Ti0.8Nb0.2O3 crystals having the same lattice parameter (a=0.395 nm) over the whole composition range. Although no dependence upon the Eu content was observed for the electron transport properties, including the density of states effective mass and carrier relaxation time for (Sr,Eu)Ti0.8Nb0.2O3, the mean free path of the phonon was reduced similar to 12% at room temperature when half of the Sr2+ was substituted by Eu2+. (C) 2007 American Institute of Physics.