Preparation of highly efficient thermoelectric Bi-doped Mg2Si0.55-xSn0.4Gex (x = 0 and 0.05) materials with a scalable mechanical alloying method

Thermoelectric properties of half-Heusler alloys

“…Currently, a high κ is the primary limitation for further improving ZT in HHs. To determine the lower limit for regulating κ, Cahill and Pohl derived the κ minimum using equation (10). 115,116 κ min = 1 2…”

“…To realize mutual conversion between thermal and electric energies based on thermoelectric effects, a variety of potential thermoelectric materials of various types and temperature ranges, such as GeTe, 6 SnSe, [7][8][9] perovskite-type SrTiO 3, 9 silicide, 9,10 Zintl phase, 9 clathrate, 9 oxide, and half-Heusler alloys (HHs), 11,12 have been developed. Owing to their excellent mechanical properties and thermal stability, 13 (V, Nb)FeSb (P-type), [14][15][16] (Ti, Zr, and Hf)CoSb (N-and P-type), [17][18][19][20] and (Ti, Zr, and Hf)NiSn (N-type) -based HHs [21][22][23] have attracted significant interests.…”

High Thermoelectric Performance of Bi-Doped Mg2Si0.4Sn0.6 and Mg2Si0.6Sn0.4 based on Recyclable Si Kerf Derived from PV Manufacturing

“…% Mg was added to the nominal compositions to compensate for the Mg loss during synthesis. 42 The milling vial was sealed under Argon atmosphere to avoid contamination. The milling process was interrupted every 8 h to manually strip off the agglomerated powder from the wall.…”

“…40,45 The substitution of Si by small amounts of Bi or Sb (2−3 at. %) has been shown to be the most efficient doping method, optimizing the electrical transport properties and providing high improvements in power factor (PF) and ZT 37,42,43,46,47 while remarkable increases in TE properties have also been reported by adding appropriate dopants such as Cr or Al at the Mg 8c (1/4 1/4 1/4) site. 48−51 A record high ZT of 1.7 has been reported by double doping with Bi and Cr.…”

“…52,54,55 Regarding the synthesis method of those materials, mechanical alloying followed by hot pressing can be deemed as a very promising and scalable technique for fabricating high-efficiency Mg 2 X-based compounds. 42 In addition to the need for waste heat recovery, other parameters are already critical for establishing a more sustainable future. The proper use of materials throughout their supply chain as well as the possible reuse/recycling of expensive waste materials from several industries are main priorities.…”