High performance p-type half-Heusler thermoelectric materials

Half-Heusler (HH) compounds are important high temperature thermoelectric (TE) materials having attracted considerable attention in the recent years. High figure of merit zT values of 0.8~1.0 have been obtained in n-type... [ view full abstract ]

Half-Heusler (HH) compounds are important high temperature thermoelectric (TE) materials having attracted considerable attention in the recent years. High figure of merit zT values of 0.8~1.0 have been obtained in n-type ZrNiSn based HH compounds. However, developing high performance p-type HH compounds with low cost is a big challenge. we show a high zT of 1.1 at 1100K can be achieved for p-type FeNb_1-xTi_xSb HH alloys and the Hf doped FeNbSb exhibits a record high zT of 1.5 at 1200K due to simultaneously optimized electrical power factors and reduced lattice thermal conductivity. In view of abundantly available elements, good stability and high zT, FeNb_1-xTi_xSb alloys can be great promising for high temperature power generation.