High density p-type Bi0.5Sb1.5Te3nanowires by electrochemical templating through ion-track lithography

Abstract

High density p-type Bi_0.5Sb_1.5Te₃nanowire arrays are produced by a combination of electrodeposition and ion-track lithography technology. Initially, the electrodeposition of p-type Bi_0.5Sb_1.5Te₃ films is investigated to find out the optimal conditions for the deposition of nanowires. Polyimide-based Kapton foils are chosen as a polymer for ion track irradiation and nanotemplating Bi_0.5Sb_1.5Te₃nanowires. The obtained nanowires have average diameters of 80 nm and lengths of 20 μm, which are equivalent to the pore size and thickness of Kapton foils. The nanowires exhibit a preferential orientation along the {110} plane with a composition of 11.26 at.% Bi, 26.23 at.% Sb, and 62.51 at.% Te. Temperature dependence studies of the electrical resistance show the semiconducting nature of the nanowires with a negative temperature coefficient of resistance and band gap energy of 0.089 ± 0.006 eV.