Ultrathin gold nanowires - chemistry, electrical characterization and application to sense cellular biology

The recent advances in the field of nanoscience and nanotechnology have motivated and challenged the fabrication of nanomaterials that can be assembled into functional networks. Based on this, ultrathin metal nanowires are considered essential building blocks that can be used to construct nanoelectronic devices for applications in sensors, photonics, and waveguides. In this thesis, we have endeavored to produce and understand the synthesis of ultrathin gold (Au) nanowires with diameter of ≈ 2 nm and lengths of up to 8 μm (aspect ratio of about 4,000). The nanowires could be synthesized employing a simple wet chemical approach using the organic molecule cis-oleylamine and AuCl as a metal precursor. Cis-oleylamine acted simultaneously as a surfactant, stabilizing and reducing agent of Au(I) ions, avoiding in this case the addition of further chemicals into the reaction. The influence of relativistic effects in the liquid phase solution of Au ions in an oxidation state +1 was investigated and demonstrated that these Au(I) species can form complexes with oleylamine. These complexes, which are believed to be formed through aurophilic interactions can induce as demonstrated from a series of spectroscopic techniques, the formation of such ultrathin nanowires.