Highly effectiveMg2Si1−xSnxthermoelectrics

Mg2Sn heterostructures on Si(111) substrate

“…In the Al-doped sample the Raman peak (520 cm -1 ) of crystalline Si also appears in the spectrum, indicating that the silicon is not fully covered by the Al-doped film, some oxide areas covers the silicon wafer, as it is proved by the image of the silicon related Raman line. This fact correlates with the high roughness measured by AFM in the samples [8]. The ratio of the Mg2Sn (peak at 220 cm -1 )…”

“…shown that the as grown films consist mainly of Mg2Sn phase and a small quantity of Mg2Si phase [8]. Far infrared (FIR) properties of grown Mg2Sn films have also proved the formation of Mg stannide with small quantity of Mg silicide.…”

“…The detailed study of Mg2Si and Mg2Sn compounds and their quasi-binary alloys [8] have shown that Mg2Si -Mg2Sn system is preferable for thermoelectrical applications due to combination of electrical properties and band structure. Since Si and Sn atoms posess large difference in atomic mass, the Mg2Si1-xSnx solid alloys exhibit small lattice thermal conductivity.…”

“…In the first time these silicides, stannides and their alloys [6][7][8] drew the attention as candidates of efficient thermoelectric materials due to their large Seebeck coefficient (), high electrical conductivity (), and low thermal conductivity (k). It is known that Mg2X compounds possess higher value of the power factor and thermoelectric figure of merit than GeSi alloys and -FeSi2 [9], so they are promising materials for production of high efficiency thermoelectric convertors.…”

Role of Structures on Thermal Conductivity in Thermoelectric Materials

“…Various substitutions have been tested and the best results have been obtained when the mass difference between elements is the highest, i.e., with Si and Sn [Fedorov 2003]. A ZT of 1.1 has then been found at 800K, a better value than with n-type Si-Ge [Zaitsev 2006]. …”