We report on the temperature dependence of the electrical resistivity and the Seebeck coefficient for the p-type Fe
2(V
1-x-yTi
xTa
y)Al alloys with compositions 0≤
x≤0.10 and 0≤
y≤0.10, in addition to the composition dependence of the thermal conductivity at room temperature. While Fe
2VAl (
x=0,
y=0) exhibits a semiconductor-like behavior in the electrical resistivity, a slight doping of Ti and Ta causes a significant decrease in the resistivity at low temperature and a large enhancement in the Seebeck coefficient, reaching 90 μV/K for
x=0.03 and
y=0.10. The power factor is found to be substantially larger than that for the p-type Fe
2(V
1-xTi
x)Al alloys so far reported. Although the thermal conductivity for Fe
2(V
1-xTi
x)Al remains in the range of 24∼28 W/mK for 0≤
x≤0.10, it decreases significantly with the Ta substitution, reaching 11∼12 W/mK for 0≤
x≤0.10 and
y=0.10. We conclude that doping of heavier atoms such as Ta reduces more effectively the lattice thermal conductivity.
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