Estimates of the thermal conductivity and the thermoelectric properties of PbTiO₃ from first principles

The lattice thermal conductivity ($\kappa_{\rm L}$) of PbTiO$_3$ (PTO) is estimated using a combination of {\em ab initio} calculations and semiclassical Boltzmann transport equation. The computed $\kappa_{\rm L}$ is remarkably low, nearly comparable with the $\kappa_{\rm L}$ of good thermoelectric materials such as PbTe. In addition, a semiclassical analysis of the electronic transport quantities is presented, which suggests excellent thermoelectric properties, with a figure of merit $zT$ well over 1 for a wide range of temperature. For thermoelectric applications, the $\kappa_{\rm L}$ could be further reduced by utilizing different morphologies and compositions.