Structure, Microstructure, and Magnetism of Electrodeposited Fe70Pd30 Nanowires

Fe-Pd nanowires for MSM applications are obtained by electrodeposition from a stable complexed Fe3+/Pd2+ electrolyte. By application of an alternating potential mode, a composition close to the intended Fe70Pd30 alloy can be achieved. In particular, the second pulse step potential E-2 is identified to be the key parameter for continuous, defect-free nanowires. The adjustment of E-2 to more positive values avoids the formation of Pd-rich segments as well as the blocking of pores by hydrogen bubbles. Detailed TEM and structural investigations reveal a bcc Fe-Pd structure and nanocrystalline deposits with grain sizes in the 5 nm range. The observed structural features are attributed to the electrochemical processes within the constraint geometry of the nanoporous template. The magnetic properties of these nanowires are controlled by shape anisotropy as well as magnetostatic interactions.