Formation of porous Mg₂(SiSn) by nanoparticle alloying and its thermoelectric properties

Thermoelectric materials and devices are regarded as promising alternatives for addressing global warming challenges. This study demonstrates the fabrication and thermoelectric properties of porous Mg₂(Si_0.4Sn_0.6). The composition inhomogeneity enhances the Seebeck coefficient, and the porous structure results in low thermal conductivity. Mg₂Si and Mg₂Sn powders are synthesized and subsequently used to create the Mg₂(Si_0.4Sn_0.6) alloy. The experimental findings reveal that via nano-engineering of earth-abundant elements, an increase in the Seebeck coefficient and a decrease in thermal conductivity can be achieved. This approach illustrates a feasible alternative to the traditional hot-pressing and spark plasma sintering processes for synthesizing porous Mg₂(Si_0.4Sn_0.6). Furthermore, this study demonstrates that porous Mg₂(Si_0.4Sn_0.6) has high performance/cost value and is a promising candidate for environmentally friendly waste-heat energy conversion.