Impact of CeO2 incorporation in electrodeposited Ni-Fe on structure and physical properties of multifunctional nanocomposites

Abstract

A new type of nanocomposite, Ni-Fe/CeO2 (∼40 nm) was prepared by cathodic co-deposition at several current densities (1.0–5.0 A dm−2) from an ethylene glycol bath. Coatings obtained from optimized bath were characterized by field emission scanning electron microscope (FESEM), energy dispersed X-ray analyzer (EDAX), X-ray diffraction (XRD), transmission electron microscopy (TEM) and atomic force microscopy (AFM). Electrochemical and physical properties of the coatings were studied as a function of variation in current density and in CeO2 particle content. Compared to Ni-Fe alloy, these nanocomposites exhibited finer grains, higher microhardness, better electrical conductivity, improved corrosion resistance and enhanced soft magnetic properties. The effect of annealing temperature on surface morphology, microstructure, texture and microhardness was also studied. CeO2 particles were found involved in managing textural evolution of Ni-Fe growth resulting in a shift in preferred orientation from (111) to (220) crystallographic plane with increasing current density. The incorporation of CeO2 particles (up to 5 wt%) also results in improvement in surface smoothness, and physical and electrochemical properties. Keywords: Ni-Fe/CeO2 nanocomposite, Corrosion, Electrical resistivity, Microhardness, Soft magnetic materials