A new d2 /do type tetragonal thermoelectric material hfsisb, a half–heusler compound: A fp–lapw method

Abstract

We have studied the electronic and thermoelectric properties of HfSiSb using first principle Density Functional Theory (DFT) within a Full Potential Linearized Augmented Plane Wave method (FP–LAPW). The electronic structure is a key in determining the thermoelectric properties. A most common generalized gradient approximation (GGA) is taken into consideration for electron exchange. The thermoelectric properties like Seebeck coefficient, electronic thermal conductivity and electrical conductivity are calculated. In addition, we have also included a lattice thermal conductivity (κp) to obtain the total thermal conductivity. The presence of total thermal conductivity gives us an exact understanding of material thermodynamics and its efficiency (ZT). HfSiSb possesses a tetragonal structure, the thermoelectric parameters are calculated along perpendicular and parallel direction. The low value of lattice thermal conductivity (below 10 W/Km) and sharp variation of ZT in the range (300 – 400) K predicts that this system is a potential thermoelectric material at room temperature. Bible 15, Fig. 5, Table 1.