Fabrication and Characters of p-Type (Bi_1-0.85Sb_0.85)₂Te₃ and PbTe Two Segments Graded Thermoelectric Materials with Different Barriers

On the basis of analysis of developing background and theory of thermoelectric graded materials, p-type (Bi_1-0.85Sb_0.85)₂Te₃ and PbTe two segments thermoelectrical graded materials (TGM) with different barriers were fabricated by conventional hot-pressing process. Metals Fe, Ni and Mg were used as barriers between two segments.The thermoelectric properties were measured. The compositions of each layer and composition distributions in and between different layers were detected. It is demonstrated that better diffusion barriers materials were metal Fe.