Fabrication and investigation of magnetic properties of CoCrSn nanowire by alternating electrodeposition method: the role of pH

Ordered 30-nm CoCrSn nanowire arrays have been prepared by co-electrodeposition of Co, Cr and Sn into pores of homemade anodized aluminum oxide (AAO). The magnetic properties of the CoxCrySn1-x-y nanowires are presented as a function of Sn and Cr contents and electrolyte pH. The result of energy-dispersive x-ray spectroscopy (EDX) showed anomalous co-deposition for Co, Cr and Sn. The nanowires have uniaxial magnetic anisotropy with easy magnetization direction along the nanowire axis due to the large shape anisotropy. As-deposited and annealed alloy nanowires, determined by x-ray diffraction (XRD), have amorphous phase. The obtained data show that the nanowires electrodeposited at different pH have significantly different magnetic properties. Magnetization measurement showed that variation in magnetic properties of the nanowire arrays rooted in surface formation of Co(OH)2 and Sn(OH)2 in upper pH. The XRD patterns of nanowire alloys obtained at pH=3, 4, 5, 6 obviously illustrated that pH affects the crystal structure of electrodeposited nanowires but has no effect on alloy nanowires. The considerable enhanced coercivity has been measured at pH=4 in changing of pH which increases the coercivity from 1333 to 1918 Orsted.