Thermoelectric properties of Eu- and Na-substituted SnTe

Thermoelectric properties of spark-plasma-sintering prepared bulk materials EuxNay square zSn1-x-y-zTe above room temperature were investigated. The implementation of Eu and Na into the SnTe lattice was monitored by refinement of lattice parameters as well as energy dispersive X-ray spectroscopy (EDXS). The binary SnTe achieved the highest ZT value of 0.63 at 786 K, and showed a hole concentration of 4.6x10(19) cm(-3) at 300 K. In comparison with pristine SnTe, the samples containing Eu had lower carrier mobility but higher Hall carrier concentration. For Eu- and Na-substituted samples, the increased hole concentration was unfavorable for the improvement of thermoelectric properties.