Cation substituted (Ca2CoO3)xCoO2 films and their thermoelectric properties

Abstract

We have controlled in-plane stress in the CoO2 sublattice of (Ca2CoO3)xCoO2 by cationic substitution of alkaline earth metals at the Ca site. The effects of the magnitude of the stress on thermoelectric properties have been investigated by using highly grain-oriented polycrystalline thin films. The in-plane compressive stress is released by the partial substitution of Sr for Ca. With increasing in-plane stress, the magnitude of thermoelectric power and resistivity increased.