Thermoelectric properties of (Fe1−xCox)2VAl Heusler-type compounds

Single thermite-type combustion synthesis of Fe2VAl for thermoelectric applications from Fe, V2O5 and Al powders

“…One is to change its composition from stoichiometric to nonstoichiometric [3][4][5], and the other is to substitute a fourth element [6][7][8][9][10][11][12][13]. The methods proposed increase the absolute values of the Seebeck coefficient and reduce the electrical resistivity of Fe 2 VAl [3][4][5][6][7][8][9][10][11][12][13]. However, the thermal conductivity of Fe 2 VAl is comparatively large as a thermoelectric material; about 28 (Wm -1 K -1 ) at room temperature, resulting in the small ZT of Fe 2 VAl [14].…”

“…Three processes of Fe 2 VAl fabrication have been conventionally reported. The first one is melting method based on ingot metallurgy [3][4][5][6][8][9][10], the second one is mechanical alloying [11][12][13], and the third one is the combination of them [7]. All of the conventional processes require pure V as raw material to synthesize Fe 2 VAl, in which V has been industrially produced by a thermite reaction from V 2 O 5 and Al using strong exothermic reaction.…”

Thermoelectric properties of Heusler-type compound Fe2V1−xNbxAl

“…[8][9][10][11][12][13][14][15][16][17][18][19] In recent years, there has been considerable interest in the electrical resistivity, specific heat, and thermoelectric properties of Fe 2 VAl. Polycrystalline (Fe 1Àx Co x ) 2 VAl (0 x 0.5) alloys were synthesized through a combined process of arcmelting, annealing, and sintering by Lu et al 20 They investigated thermoelectric properties from 300 to 850 K. A Fe 2 VAl sintered alloy with fine microstructure was synthesized to evaluate the effect of grain size on thermoelectric properties by Mikami. 21 Kumar et al calculated the electronic and optical properties for Fe 3Àx V x Al (x ¼ 0-3) compounds with the aim of studying the effect of increasing the concentration of vanadium.…”

Chemical segregation and precipitation at anti-phase boundaries in thermoelectric Heusler-Fe2VAl

“…Although the power factor is high, its high thermal conductivity (κ) is the major limiting factor in its TE performances [8]. Different routes to enhance phonon scattering and decrease κ have been investigated, such as doping [10,[12][13][14], off-stoichiometry [15,16], introduction of defects and exploiting disorder in the structure [17][18][19][20].…”