The thermoelectric properties of ZrNiSn-based half-Heusler materials were hindered due to their high thermal conductivity. In order to reduce the lattice thermal conductivity, the high-entropy alloys ZrNiSn and Zr0.5Hf0.5Ni1-x PtxSn (x=0, 0.1, 0.15, 0.2, 0.25, 0.3) were prepared by levitation melting and spark plasma sintering. The configurational entropy of the alloys was manipulated by Hf substitution for Zr and Pt substitution for Ni. The effects of configuration entropy on the thermoelectric properties were investigated. In this work, the minimum sum of lattice thermal conductivity and bipolar thermal conductivity (κl+κb)= at 673 K for Zr0.5Hf0.5Ni0.7Pt0.3Sn was optimized (2.1 W• m -1 • K -1 ), which is significantl y reduced b y about 58 % when compared with ZrNiSn. This new finding proposes an effective strategy for reducing the lattice thermal conductivity of ZrNiSn-based alloy to offer great potential for further improvement of thermoelctrics.

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