Thermoelectric Properties of Mo and Ge co-substituted CrSi2

The thermoelectric properties of Mo and Ge co-substituted CrSi2 have been investigated. Polycrystalline samples of (Cr1−xMox)Si2 (x = 0, 0.02, 0.04, 0.06, 0.08, and 0.10) and (Cr0.92Mo0.08)(Si1−yGey)2 (y = 0, 0.01, and 0.02) were prepared by the two-step arc-melting method followed by spark plasma sintering and annealing. Powder X-ray diffraction confirmed that single-phase (Cr1−xMox)(Si1−yGey)2 samples were obtained. Mo and Ge co-substitution in CrSi2 resulted in both an increase in the power factor and a large decrease in the thermal conductivity, which resulted in a high figure-of-merit (zT) value for the (Cr0.92Mo0.08)(Si0.99Ge0.01)2 sample (zT = 0.29 at 700 K). This zT value is the highest reported value for CrSi2-based thermoelectric materials.