Neutron diffraction texture analysis and thermoelectric properties of BiCaCoO misfit compounds

Abstract

Sintered, textured and single crystal products of the layered misfit [Bi 0.81CaO 2] 2[CoO 2] 1.69 cobaltite have been successfully synthesized and characterized. Based on structure and texture models, the orientation distribution of the hot-forged sample was successfully analysed by neutron diffraction. The results gave a clear description of the fiber texture with c-axes of the plate-like grains aligned parallel to the hot-forging direction. In terms of transport properties, the decrease of the electrical resistivity according to the degree of alignment and crystallinity of the materials evidenced the important role of the texturation and the strong anisotropy existing in these misfit layered cobaltites.