Enhanced thermoelectric performance of Bi0.5Sb1.5Te3 alloys via amorphous glass particle integration

Enhancing thermoelectric performance requires optimizing both power factor and thermal conductivity, a key challenge addressed through innovative composite strategies. In this study, milled amorphous glass particles (GPs) produced by high-energy ball milling (wt%) were added to BiSbTe-based alloys, and composites were obtained by spark plasma sintering. The results indicate that as the GPs content increases, the thermal conductivity (k) decreases, which is 6% lower than the BiSbTe matrix owing to enhanced phonon scattering of particles as well as a combination of different scattering mechanisms, including point defects, grain boundaries, and dislocations. This can provide a platform for maximizing the reduction of lattice thermal conductivity through the scattering of a full spectrum of phonons from low to high frequencies. Electrical conductivity increased by 10% with higher GPs content, while the Seebeck coefficient remained nearly constant, indicating a promising way to reduce thermal conductivity while enhancing electrical performance.