Thermoelectric Properties of n-type Full-Heusler Fe2−2xCo2xTiSn Prepared by an Ultra-fast Synthesis Process

Full-Heusler alloy Fe2TiSn was predicted to be a potential thermoelectric material with high mechanical properties and stability. Fe2TiSn was usually prepared by arc-melting followed by annealing for 2 weeks, which takes a long time and consumes a large amount of energy. In this paper, Fe2TiSn was prepared by an ultra-fast method, self-propagating high-temperature synthesis (SHS) combined with spark plasma sintering. The bulk materials with uniform element distribution, well controlled composition and relative densities of over 97.5% were prepared. The undoped Fe2TiSn samples show p-type transport behavior. Co was heavily doped at the Fe site to prepare n-type Fe2−2xCo2xTiSn samples. The thermoelectric properties measurements carried out on the Co-doped samples show a highest ZT = 0.02 at 300 K, which is about tripe the performance of the pristine Fe2TiSn. This study provides a new approach for the rapid and low-cost preparation of full-Heusler thermoelectric materials.