Effect of composition, electrolyte pH, annealing temperature and electrodeposition waveform on the magnetic properties of Co-Cu nanowire alloys

Arrays of Co0.2Cux, with 0<x<0.1, nanowires (NWs) have been synthesized. CoCu NWs have been grown into the AAO templates by ac electrodeposition. The anodic aluminum oxide template (AAO) were synthesized by a two-step anodization process of pure Al foils in sulfuric acid. The effect of small addition of Cu to Co NWs by varying the concentrations of Cu+2 ions in the electrolyte, as well as the effect of annealing on the magnetic properties of NWs was investigated. Eventually, the effect of changing waveforms applied to nanowire deposition was studied. The results showed that the coercivity of cobalt NWs decreased by adding copper impurity as a non-magnetic material from 1337 Oe to 660 Oe. By annealing of the alloy NWs up to 450 °C, the coercivity increases from 1140 Oe value for pure Co NWs up to 1541 Oe for CoCu NWs due to the removal of structural stresses of the nanowire.