Preparation and thermoelectric transport properties of high-performance p-type Bi2Te3 with layered nanostructure

High performance ${\mathrm{Bi}}_2{\mathrm{Te}}_3$ bulk materials with layered nanostructure have been prepared by combining melt spinning technique with spark plasma sintering, and their thermoelectric transport properties are investigated. The electrical conductivity increases greatly and the lattice thermal conductivity decreases significantly with the increase of the roller’s linear speed. These lead to a great improvement in the thermoelectric figure of merit $\left(ZT\right)$ . The maximum $ZT$ value of 1.35 is obtained at $300\mathrm{K}$ for the sample which is prepared by melt spinning with roller linear speed of $40\mathrm{m}∕\mathrm{s}$ . Compared with the zone melting sample, it increases by 73% at the same temperature.