Metal Displacement Deposition: a facile via to grow metal and metal oxide nanostructures

Nanostructured materials have received increasing attention because of their high chemical reactivity that allows an extensive use in many fields, like catalysis, electrosynthesis, sensors, and so on [1]. Taking into account that size plays a fundamental role for the properties of nanostructures, it is of relevant importance for their applications to develop a facile method of synthesis. In our previous works, we have described a template synthesis of metal nanowires through a simple novel route [2-4]. In particular, using a combination of template deposition and metal displacement reaction, we have fabricated pure metal nanowires with a well-defined morphology. This type of template synthesis is based on the galvanic contact between a sputtered metal film, covering the bottom of the template, and a less noble metal, partially exposed to the solution. This kind of deposition can be carried out at room temperature without using energy or specific equipments. Consequently, the present route for the preparation of metal nanowires is cheap and simple, and it can also be applied to the synthesis of other metallic nanostructures. Recently, we have successfully extended this technique to the fabrication of large arrays of free-standing oxide nanostructures. We will show that displacement reaction leads to the growth of nanotubes and nanowires of either amorphous or nanocrystalline oxides of different metals. A full characterization was performed by means of several techniques (EDS, SEM, RAMAN, XRD) both to study chemical composition and get structural information. References 1 L. Zhang, X. Fang, C. Ye, Controlled Growth of Nanomaterials, World Scientific, Hackensack, NJ, 2007. 2 R. Inguanta, S. Piazza, C. Sunseri, It. Pat. VI-2007-A000275, 2007. 3 R. Inguanta, S. Piazza, C. Sunseri, Electrochem. Commun. 10 (2008) 506. 4 R. Inguanta, S. Piazza, C. Sunseri, Electrochem. Commun. 11 (2009) 1385.