Novel nanoarray structures formed by template based approach: Characterization and electrochemistry

Several different methods have been developed to form nanomaterials. The methods employed depend on the desired properties and applications. One of the broadest and important synthetic approaches for nanomaterials is based on templates. Templates provide a predetermined configuration or cast to guide the formation of nanomaterials with the desired morphology. They provide a very rich method to fabricate nanomaterials with a wide range of different morphologies and tunable sizes. After a materials formation reaction, the template can be sacrificially removed, leaving behind the final product that replicates the morphology of the original template. The synthetic methods based on templates overcome a weakness of other synthesis methods by providing good control of the final morphology of the produced nanomaterials. In addition, the methods are very general with respect to the types of materials that may be prepared.; The main focus in this thesis is to produce highly ordered novel structures and arrays at nano/micro scales that are of electrochemical interest with good control of size and shape. Template-based approaches were used here to fabricate nano/micro tubes, rods, wires and porous films. By this approach, we incorporated electroless deposition and electrodeposition reactions with various templates, so that once the template is removed, the desired structures are reveled. Among the templates that were used are: track etched polycarbonate membrane, anodized aluminum oxide membrane and silica colloidal sphere. Electroless deposition and electrodeposition within the template to form nanomaterials is very attractive approach because it can be carried out under conditions mild enough to avoid any damage of both the desired materials and the template used. This approach makes possible the formation of a wide range of nanomaterials that may be useful technologically for catalytic, electronic, and energy storage applications. Examples of the nanostructures that were made include polyvinylferrocene porous film, V2O5 nano wires, and arrays of metal nanotubes such as Pd, Ni and Pt.; With the aid of electrochemical techniques such as Cyclic Voltammetry and Galvanostatic measurements, nanomaterials fabricated in this thesis were used as hosts for hydrogen (fuel cell applications) and lithium (Li battery applications).