Microstructure and magnetic properties in arrays of ac electrodeposited FexNi۱−x nanowires induced by the continuous and pulse electrodeposition

Abstract

FeNi nanowires were fabricated by ac and pulse electrodeposition into the alumina template matrix. The effects of continuous ac electrodeposition as well as pulse features on the structure and magnetic properties of the nanowire arrays were studied. The microstructures and magnetic properties of the FexNi1−x nanowires are seen to be independent of the deposition frequency and off-time between the pulses. The ac electrodeposited Ni nanowires were not formed at more than 400 Hz deposition frequency, while the FexNi1−x nanowires, containing a small amount of Fe, formed in the all frequencies. For x less than 50% the coercivity slowly increases but over 50% Fe added to the FeNi alloy increases the coercivity with a higher rate and maximum coercivity was seen for the Fe0.97Ni0.03. The Fe and FexNi1−x nanowires containing less than 30 at.% Ni was seen to have a bcc structures with (110) preferential direction while FexNi1−x nanowires with more than 30 at.% Ni showed (110) bcc (Fe) and/or (111) bcc (FeNi) plus (111) fcc (Ni). A preferential (111) fcc structure was obtained for the Ni nanowires.