Preparation of Highly Conductive Gold−Poly(3,4-ethylenedioxythiophene) Nanocables and Their Conversion to Poly(3,4-ethylenedioxythiophene) Nanotubes

Gold^_poly(3,4-ethylenedioxythiophene) (Au-PEDOT) nanocables were synthesized at room temperature by one-step interfacial reaction of EDOT (in organic phase) and HAuCl₄ (in aqueous phase) without the assistance of a surfactant, a template, or a stabilizer. The coaxial nanocables have lengths of several micrometers, outer diameters around 50 nm, and central cores around 30 nm. The room-temperature conductivity of the as-prepared nanocable pallet was measured to be about 770 S cm^-1, and it changed from negative to positive temperature coefficient of resistivity (TCR) at around 50 K. The single Au-PEDOT nanocable exhibits as a semiconductor in the temperature range of 100−300 K with room-temperature conductivity as high as 2.3 × 10³ S cm^-1. Dissolution of the Au component from the nanocables using saturated I₂ solution resulted in the formation of hollow PEDOT nanotubes with diameters around 50 nm, and gold nanowires were also produced by oxygen plasma decomposition of the PEDOT skins of the nanocables.