Sn-doped bismuth telluridenanowires with high conductivity

Abstract

Bismuth telluride (Bi₂Te₃) nanowires with sub-100 nm diameters were synthesized by Au–Sn co-catalyzed chemical vapor deposition. These Bi₂Te₃ nanowires were single crystals with a hexagonal lattice. The Sn catalyst played a key role in achieving the one-dimensional nanowire structures, while the absence of Sn resulted in other morphologies such as nanoplates, nanooctahedrons and nanospheres. Raman spectra revealed that compared to the Bi₂Te₃ bulk materials, the Bi₂Te₃ nanowires displayed an A_1u spectral peak, implying the breaking of symmetry. The temperature-dependent electrical measurement indicated that these Sn-doped Bi₂Te₃ nanowires were metallic, with a high conductivity of 1.6 × 10⁵ S m⁻¹ at 300 K.