Matrices, based on nanostructured porous anodic alumina, for functional applications

Abstract

Two-step electrochemical anodization was used for obtaining matrices based on porous anodic alumina (MPAA). Three series of experimental samples were made: 1 – PAAM with thickness 1.3–2.5 μm and 70 nm diameter, 2 – 70.0 μm thickness and 50–75 nm diameter and 3 – 13.5–60.0 μm thickness and 100–200 nm diameter. The pore filling of MPAA was realized using electrochemical deposition. As a result Ni nanopillars, Ni and multilayered Cu/CoNi nanowires were formed. The scanning electron microscopy, vibrating magnetometry, voltammetry techniques and four-probe method were used for experimental samples investigations. The magnetic characteristics of Ni nanowires showed that nanowires in MPAA have ferromagnetic properties, since the coercitivity riches up to 750 kOe and squareness ratio up to 0.65. The study of the electrochemical behavior of the Ti/Al2O3/Ni nanocomposite material in the potential range from –450 to +450 mV in 0.9 % NaCl aqueous solution demonstrated its high corrosion resistance properties. The correlation of the GMR of multilayered Cu/CoNi nanowires to the topological parameters of MPAA, the number of layers, the MPAA and partial layers thickness, and chemical purity has been determined. Thus, it has been demonstrated the prospects of use of matrices based on porous anodic alumina as a base material for the template synthesis of functional ferromagnetic nanomaterials for various practical applications.