Electronic structure and thermoelectric properties of narrow-band-gap intermetallic compound Al2Fe3Si3

Phase stability and thermoelectric properties of semiconductor-like tetragonal FeAl2

“…As shown in the inset of Figure 8(d), the temperature dependence of κ ph from 150 K to 300 K was proportional to 1/T, which suggested that Umklapp scattering played the main role in the decrease of κ ph . One can compare the thermoelectric properties of t-FeAl 2 with those of other intermetallic thermoelectrics, Fe 2 VAl [38][39][40][41][42] and Al 2 Fe 3 Si 3 [43][44][45][46]. The κ ph of t-FeAl 2 was several times larger than that of Al 2 Fe 3 Si 3 .…”

First-Principles Study on Lattice Dynamics and Thermal Conductivity of Thermoelectric Intermetallics Fe3Al2Si3

“…The temperature dependence shows a typical decay behavior, κ ph ∝ T −1 . Three experimental values of stoichiometric and non-stoichiometric polycrystalline samples from References [2,3] are also shown in Figure 5. All the experimental values significantly deviate from the calculated results.…”

“…κ can be considered as the sum of two portions: the electronic (κ el ) and lattice (κ ph ) thermal conductivity. Recently, an Fe-Al-Si ternary intermetallic compound Fe 3 Al 2 Si 3 has been considered as a promising candidate of a novel practical thermoelectric material for lowtemperature applications [2][3][4][5][6][7]. Although the ZT value of Fe 3 Al 2 Si 3 is much lower than any other practical thermoelectric materials, it has some significant advantages: (1) lowcost and non-toxic, (2) high chemical and thermal stabilities, (3) an excellent oxidation resistance, and (4) a good balance of mechanical properties [6,7].…”

“…To further improve the thermoelectric performance of Fe 3 Al 2 Si 3 toward practical applications, we need to reduce the lattice thermal conductivity. The lattice thermal conductivity of undoped Fe 3 Al 2 Si 3 is 5-6 W m −1 K −1 at room temperature [2,3]. Shiota et al reported a significant reduction to 3.5-4.5 W m −1 K −1 by Co doping on Fe site [5].…”

Improvement of the Thermoelectric Performance of Pseudogap and Narrow-Gap Compounds via Theoretical Calculations

“…26) The recently characterized Al 2 Fe 3 Si 3 ternary alloy composed of only common and low-cost elements is attractive for low-temperature applications below 500 K. 27,28) The conduction type and power factor of this material can be simultaneously tuned by controlling the Al and Si content. At this stage, although the obtained S 2 · values of these Al-based ternary materials are lower than those of conventional thermoelectric materials, their non-toxic properties and the low-cost of the materials, in particular for the Al 2 Fe 3 Si 3 compound, are attractive for the fabrication of thermoelectric modules.…”