Thermoelectric and Mechanical Properties of Environmentally Friendly Mg₂Si_0.3Sn_0.67Bi_0.03/SiC Composites

In this work, polycrystalline n-type Mg₂Si_0.30Sn_0.67Bi_0.03 dispersed with x wt % β-SiC nanoparticles (x = 0, 0.5, 1.0, 1.5, and 3.0) thermoelectric materials were fabricated by a solid-state reaction in a low-cost container, consolidated by hot-pressing. We obtained figure of merit values zT above 1.4 at 773 K along with enhanced mechanical properties by adding β-SiC into an Mg₂Si_0.30Sn_0.67Bi_0.03 matrix. Incorporation of SiC nanoparticles has thusly simultaneously increased toughness and, depending on the SiC content, thermoelectric performance. The peak figure of merit was improved from zT = 1.33 for Mg₂Si_0.30Sn_0.67Bi_0.03 to 1.45 for Mg₂Si_0.30Sn_0.67Bi_0.03 with 3 wt % at 773 K.