Ewa Brancewicz

Electrochemical Preparation of Magnetic Nanowires

Electrochemistry is a method, which can be used for creation of nanomaterials. This method has big advantage such as no restriction for shape and size of the sample and do not need to involve expensive equipment for the sample preparation. In the paper the preparation of Fe nanowires as well as Co and Ni are presented. The diameter and length of obtained nanowires can be tuned by properties of the template porous material and time of deposition, respectively. The quality of the nanowires depends also from deposition mode (AC - alternating current or DC - constant current) and pH of the solution. The anodization conducted in oxalic acid allows us to obtain anodic alumina oxide (AAO) with the smallest pore diameter of about 40 nm. Usage of phosphoric acid results in largest pores with diameter around 120 nm. The deposited material inside the pores has diameter of the templates. The length can be as large as the thickness of the oxide and reach up to around 1 μm. The wires shows magnetization direction along main axis. The morphology of wires were studied by atomic force microscopy (AFM) and scanning electron microscopy (SEM). The magnetic characterization of the structures was done by magnetic force microscopy (MFM) and Mössbauer spectroscopy.

Magnetic Nanotubes as an Element in Biocomposites

In this work magnetic nanorods have been synthesized by electrodeposition inside the nanotubes fixed to anodic alumina oxide (AAO). The used templates have the pore diameter of 120 nm. In the first step different combinations of 3d elements oxide nanotubes such as: CoO, NiO, NiFe2O4, CoFe2O4 and Fe3O4, have been successfully fabricated inside the nanopores by wetting chemical deposition followed by thermal decomposition. Oxide/Fe, wires were obtained in the next step by electrodeposition The morphology of obtained structures were studied by atomic force microscopy (AFM) and scanning electron microscopy (SEM). The magnetic properties of the nanostructures were determined on the base of behavior of the structures in external magnetic field. Local magnetic moment orientation is not strictly determined up to now. The potential biological application as an enzyme carrier was tested.