  In this study, we examined the thermoelectric properties of the layered
bismuth-chalcogenide-based (BiCh2-based) compound LaOBiSSe, which is expected
to be a new candidate material for thermoelectric applications. Densified
samples were obtained with a hot-press method. The results of the X-ray
diffraction measurements showed that the samples obtained were weakly oriented.
This affected the resistivity (r) and Seebeck coefficient (S) of the samples
because they are dependent upon the orientation of the crystal structure. The
values obtained for the power factor (S2/r) when measured perpendicular to the
pressing direction (P1) were higher than that when measured parallel to the
pressing direction (P2). The thermal conductivity (k) of the samples was also
sensitive to the orientation. The values of k measured along P2 were lower than
that measured along P1. The highest figure-of-merit (approximately 0.36) was
obtained at around 650 K in both directions, i.e., P1 and P2.
