Thermoelectric Properties of Mn-Doped Cu2SnSe3

We report the thermoelectric properties of Mn-doped Cu2Mn Sn1- Se-3 compound, with ranging from 0.005 to 0.1 at temperature ranging from 80 K to 723 K. All samples maintain cubic zincblende-like structure, and no impurity phase was detected. The electrical resistivity decreases rapidly when Mn4+ replaces Sn2+ in the matrix. The excess Mn impurities in the = 0.05 and = 0.1 samples also affect the Seebeck coefficient. The total thermal conductivity is increased for Mn-doped samples except for the = 0.005 sample. In all, both power factor and figure of merit are improved by Mn doping over the entire temperature range. The value of the = 0.02 sample reaches 0.035 at 300 K, and for = 0.01 reaches 0.41 at 716 K, which are comparable to the best thermoelectric performance for ternary Cu-based compounds.