The preparation of nanoporous membranes (typically alumina) by anodization processes where long range hexagonal ordering is induced by self-assembling or nano-imprint. Anodic alumina membranes are subsequently employed as templates for the preparation of different ordered nanostructures.
Self-assembled nanopores are filled by electroplating with metallic elements to obtain highly-ordered hexagonal arrays of densely packed metallic single nanowires as FeNi, Fe, Co and multilayered nanowires as Co/Cu. Radial metallic nanowires are also obtained when electroplating is performed in anodic cylindrical porous alumina wires. Semiconductor ZnO-like nanowire arrays are also investigated.
Various replica/antireplica processes allow us the production of a broad spectrum of high-ordered magnetic nanocomposites reproducing the original ordering as nanohole or antidot arrays in metallic membranes (i.e., Ni, Py), mechanically hard nanostructures for imprinting (i.e., TiN), polymeric membranes with embedded magnetic nanoparticles (i.e., CoNi, FePt), or nanoparticle-like Co structures on polymeric surfaces.
Anodic alumina membranes are also employed as masks to reproduce ordering onto oxide and metallic surfaces by ion irradiation and implantation.