Synergistically improving thermoelectric and mechanical properties of Ge0.94Bi0.06Te through dispersing nano-SiC. (1st July 2020) - Jin, Yang
Abstract: In this paper, Ge0.94 Bi0.06 Te was firstly fabricated by mechanical alloying. Compared with the Ge0.94 Bi0.06 Te sample prepared by the melting process, the maximum ZT achieved an improvement from 1.4 to 1.8. The thermoelectric performance of Ge0.94 Bi0.06 Te can be improved through suppressing Ge vacancies and refining grains via mechanical alloying. Further introducing nano-SiC into the matrix of Ge0.94 Bi0.06 Te improves thermoelectric performance by increasing Seebeck coefficient and reducing thermal conductivity. Meanwhile, the mechanical properties including the microhardness and Young's modulus are also enhanced by dispersing nano-SiC. Consequently, a maximum ZT ~ 2.1 at 723 K was achieved in GeTe-based materials. Graphical abstract: Ge0.94 Bi0.06 Te bulk materials dispersed with nano-SiC exhibit superior thermoelectric and mechanical properties. A maximum ZT ~ 2.1 at 723 K and a maximum microhardness ~ 1.98 GPa at room temperature were achieved in GeTe-based thermoelectric materials. Image, graphical abstract