Structural and thermoelectric characterizations of high pressure sintered nanocrystalline Bi2Te3 bulks

► Densified Bi2Te3 nanocrystalline bulks fabricated using high pressure sintering. ► Structural and thermoelectric properties are characterized. ► A preferential sintering pressure about 2 GPa is revealed. ► ZT larger than 0.8 for the 2 GPa HPS sample from 300 K to 460 K. ► A maximum ZT of 1.03 is achieved at 403 K for the 2 GPa sample.