Theoretical study of thermoelectric properties of $\textrm{CeIr}_\textrm{4} \textrm{P}_\textrm{12}$ filled skutterudite for energy conversion

Abstract

The structural, elastic, thermodynamic and thermoelectric characteristics of the $\textrm{CeIr}_\textrm{4} \textrm{P}_\textrm{12}$ skutterudite have been predicted for the first time by applying density functional theory and the semi-classical Boltzmann simulations. Firstly, the structural-magnetic stability was verified through ground-state energy calculations obtained from structural optimizations. The predicted single-crystal elastic constants (${C}_{ij}$) show that the title compound is mechanically stable. At the same time, it turns out to be dynamically stable where all the calculated phonon frequencies have positive values. The cohesive energy was calculated to verify the energy stability of the material considered. We also determined the variations of some macroscopic physical parameters as functions of temperature, namely the thermal expansion coefficient, the lattice thermal conductivity. Furthermore, we investigated the temperature dependencies of some thermoelectric coefficients such as electronic thermal conductivity, and figure of merit. Such encouraging results indicate that the compound is a potential candidate for thermoelectric devices.