Transport properties of Bi43Se4Te53 thermoelectric alloy fabricated by mechanical grinding and pulse discharge sintering

摘要

Mechanical grinding followed by pulse discharge sintering was applied to fabricate n-type Bi43Se4Te53 thermoelectric materials. Calorimetric measurements demonstrated that a Se-rich phase was developed from Bi2(Se, Te)3 phase after 10h of milling. However, when the milling time was extended to 25 h or longer, a Te-rich phase was formed. Hall measurements showed that the development of the Se/Te-rich phase considerably increased the carrier concentration but decreased the carrier mobility. The oxygen contamination in the smashed powders was also an important consideration for the degeneration of the figure of merit of the sintered samples.