  Materials design based on first-principles electronic calculations has proven
a fruitful strategy to identify new thermoelectric materials with a favorable
figure of merit. Recent electronic structure calculations predict that in
cobalt-based half-Heusler systems a power factor higher than in CoTiSb can be
achieved upon p-type doping of CoVSn, CoNbSn, CoTaSn, CoMoIn, and CoWIn. Here,
using a first-principles approach and semi-classical Boltzmann transport
theory, we investigate the electrical and thermal transport properties of these
materials. The calculated thermal conductivity at room temperature of all the
systems is lower than that of CoTiSb, with CoMoIn and CoWIn having an almost
3-fold lower thermal conductivity than CoTiSb. We also provide conservative
estimates of the figure of merit for these systems which all turn out to be
higher than in CoTiSb and to have a maximum value for CoWIn.
