Investigation of micro-indentation hardness of Bi2Te3 based composite thermoelectric materials

We have successfully synthesized Bi0.5Sb1.7Te3+x (x = 0, 0.12, 0.14) composite thermoelectric materials via solid state reaction followed by Spark Plasma Sintering (SPS). The structural characterization of these materials carried out by X-ray diffraction reveals to be composite phase consisting of Bi2Te3-type phase with small amount of Te and Sb phase. The micro-hardness performed on samples Bi0.5Sb1.7Te3+x(x =0, 0.12, 0.14) reveals the reduction of VHN with increasing Te concentration as compared to that of single phase state –of-the-art Bi0.5Sb1.5Te3 thermoelectric materials.