Thermoelectric properties of Cr₃S₄-type selenides

Several compounds with the Cr₃S₄ structure type have been studied for their thermoelectric properties. All exhibit low lattice thermal conductivity of about 15 mW/cmK, independent of temperature. Many of the compounds, such as Co₃Se₄, Ni₃Se₄, Fe₃Se₄, Ti₃Se₄, FeNi₂Se₄, and FeCo₂Se₄, are metals with relatively low electrical resistivity and Seebeck coefficient. The Cr containing compounds, such as Cr₃Se₄, NiCr₂Se₄, CoCr₂Se₄, and FeCr₂Se₄, have the largest Seebeck coefficients and highest resistivity. The most promising of these materials for thermoelectric applications is FeCr₂Se₄.