Thermoelectric and mechanical characterization of the utilization of FeTe as an electrode for iodine-doped PbTe

In addition to the thermal and electrical characteristics of the thermoelectric material , the energy conversion efficiency of TE devices is influenced by other factors including the interface resistance, which in turn is affected by chemical changes or mechanical failure. We have investigated the use of FeTe as an electrode for iodine-doped PbTe. The telluride of iron has CTE and work function values that match well with those of PbTe. The FeTe/PbTe contact was determined as ohmic in nature with low resistance. Contact resistance and shear strength values were determined over aging times of up to 400 h at 573 K and were found to be nearly unchanged. In contrast, samples in which Fe was used as electrode showed significant decrease in shear strength and a significant increase in joint resistivity over the same aging conditions. From the electrical and thermal characterization, the conversion efficiency of the FeTe/Pb 1.0004 Te 0.997 I 0.003 /FeTe single leg was determined as 4.678% for T h = 673 K and T c = 300 K.