Peculiarities of structural disorder in Zr- and Hf-containing Heusler and half-Heusler stannides

► The homogeneity regions were found for ZrNiSn, ZrNi2Sn and HfNiSn, HfNi2Sn compounds. ► The crystal structure of HfNiSn appeared to be disordered. ► The Ni doping of ZrNiSn and HfNiSn allows tuning up to 10% the thermoelectric power factor.