The effect of Sr and Sb co-doping on structural, morphological and thermoelectric properties of BaSnO3 perovskite material

Abstract

BaSnO3 (BSO) is one of the promising perovskite materials for high temperature thermoelectric applications. The pure BSO, Sr and Sb co-doped BSO materials were prepared by the polymerization complex method and annealed at 1473 K. The X-ray diffraction patterns confirmed the cubic structure of pure BSO and Sr-Sb co-doped BSO. The addition of Sr and Sb changed the morphology of BSO from microstructures to the layered and polygonal shaped nanostructure. The valence states of each elements of the samples were confirmed by the X-ray photoelectron spectroscopy. The addition of Sb5+ atom in Sn4+ site modified the electronic band structure thereby enhanced electrical conductivity. The highest power factor of 25.3 μW/(m K2) was achieved for the SrSb5(Sr: 5 mM and Sb: 5 mM in the polymerization complex method) at 578 K. The reduced thermal conductivity and increased power factor in SrSb5 resulted in the higher figure of merit of 2.1 × 10−3 at 578 K.