Metallic nanowires are synthesized by electrochemical growth in nanopores of either track-etched polycarbonate membranes or anodized aluminum films. The potentiostatic growth is systematically investigated for track-etched membranes with nominal pore diameters dN between 10 and 80 nm. For this model system, the cross-section of the metallic wires is found to vary: the wire diameter, which is argued to directly reflect the pore diameter, is observed to be substantially larger in the middle than at both ends. Therefore, the pores are not cylindrical with constant cross-section, but appear to be `cigar-like'. Inside the membranes, the pores are wider by up to a factor 3. The aluminum oxide template has successfully been used to prepare a colloidal suspension of gold needles (anisotropic metallic colloid) by growing Au wires in the pores, dissolving the aluminum oxide and finally stabilizing and dispersing the `nano-rods' in water. Visible near-infrared absorption spectroscopy reveal two absorption maxima caused by the anisotropy of these scatterers. The maxima can be assigned to a longitudinal and transversal plasma resonance.
|Number of pages||7|
|Journal||Materials Research Society Symposium - Proceedings|
|Publication status||Published - 1 Jan 1997|
|Event||Proceedings of the 1996 MRS Fall Meeting - Boston, MA, USA|
Duration: 2 Dec 1996 → 5 Dec 1996