Characterization of nanocrystalline Ni-Cu thin films electrodeposited onto ITO coated glass substrates: effect of pretreatment current density

Abstract

In this work, Ni-Cu films were grown onto indium tin oxide coated glass substrates without and with galvanostatic pretreatment process at different current densities. In all cases, Ni-Cu films were electrodeposited at a constant deposition potential of -1,800 mV versus saturated calomel electrode. After that, the surface morphology and structural properties of electrodeposited Ni-Cu films in dependence of pretreatment current density were studied. X-ray diffraction analysis showed that all films have face-centered cubic structure and consist of segregated two Ni-rich and Cu-rich phases regardless of pretreatment current density. The compositional analysis carried out by energy dispersive X-ray spectroscopy revealed that all films contain almost 90 wt% Ni and 10 wt% Cu. The average crystallite size decreased with decreasing pretreatment current density towards more negative values without inducing significant changes in the composition of the films. It was found that the preferred orientation of all films is in the [111] direction regardless of pretreatment current density. The effect of galvanostatic pretreatment process on the surface morphology investigated using a scanning electron microscopy and an atomic force microcopy were also discussed by means of obtained results.