Realizing p -type NbCoSn half-Heusler compounds with enhanced thermoelectric performance via Sc substitution

摘要

N-type half-Heusler NbCoSn is a promising thermoelectric material due to favourable electronicproperties. It has attracted much attention for thermoelectric applications while the desiredp-type NbCoSn counterpart shows poor thermoelectric performance. In this work, p-typeNbCoSn has been obtained using Sc substitution at the Nb site, and their thermoelectricproperties were investigated. Of all samples, Nb0.95Sc0.05CoSn compound shows a maximumpower factor of 0.54 mW/mK2 which is the highest among the previously reported values ofp-type NbCoSn. With the suppression of thermal conductivity, p-type Nb0.95Sc0.05CoSn compound shows the highest measured figure of merit ZT = 0.13 at 879 K.