Thermoelectric properties of individual electrodeposited bismuth telluride nanowires

Abstract

For an electrodeposited bismuth telluride $\left({\mathrm{Bi}}_x{\mathrm{Te}}_{1-x}\right)$ nanowire from one batch with $x$ found to be about 0.46, the Seebeck coefficient $\left(S\right)$ was measured to be 15%–60% larger than the bulk values at temperature $300\mathrm{K}$ . For four other nanowires from a different batch with $x\approx 0.54$ , $S$ was much smaller than the bulk values. The electrical conductivity of the nanowires showed unusually weak temperature dependence and the values at $300\mathrm{K}$ were close to the bulk values. Below $300\mathrm{K}$ , phonon-boundary scattering dominated phonon-phonon Umklapp scattering in the nanowires, reducing the lattice thermal conductivity.