Synthesis and Characterization of Nanoporous Alumina Membranes

Porous alumina forms on the surface of aluminum in a self organized manner when anodized in an acid under specific conditions. Such templates have recently emerged as an important self-assembly method for nanofabrication.They can be used in different ways to synthesize self-assembled arrays of nanowires and nanodots of a variety of materials, such as metals, alloys, binary compounds, and multilayers. Characterization of these materials can easily be achieved by releasing the nanowires from the template. Magnetic, electric, transport, and optical measurements all contribute toward the exploration of the fundamental properties of nanostructured materials and point toward their technological potential. Alumina templates have high porosities. They can easily be prepared in the laboratory with good control over the size (length and diameter) of the pores. Under certain conditions, very good periodicity of the pore arrangement can also be obtained. Porous alumina templates can also withstand high temperatures, which may be necessary in some cases to anneal the deposited material.