Thermoelectric performance of graphene composited BiSbTe bulks by high pressure synthesis

A simple and rapid high-pressure-and-high-temperature (HPHT) method is introduced to synthesize Bi0.4Sb1.6Te3 bulks with various graphene content (0, 0.02, 0.05, and 0.1 wt%) in 30 min at 4 GPa. Multiple microstructures are generated by pressure-quenching, including nanograins and lattice structural disorders. The graphene addition exhibits inverse effect on the thermoelectric performances. A maximum ZT = 1.26 at 423 K is achieved for Bi0.4Sb1.6Te3 with 0.05 wt% graphene at 4 GPa.176