Abstract:Via altering the melting time and temperature, the effect of the melt super-heat treatment on the solidification, microstructure and electrical transport property of P-type Bi0.5Sb1.5Te2.85Te0.05 was estimated. The results show that the start nucleation temperature and coagulation time decrease, and the microstructure is refined with the extension of melting time and the increase of melting temperature. Furthermore, the electrical resistance significantly decreases, leading to an enhanced power factor (PF). Therefore, the sample melted in 1373K for 4h exhibits the highest value of PF ~25.5μW cm-1 K-2 at 305K.
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