Morphology, structure, and magnetic properties of electrodeposited Ni films obtained from different pH solutions

Nanocrystalline nickel (Ni) films were obtained by electrodeposition from chloride aqueous solution with different pH values. The influence of electrolyte pH on the morphological, structural, and magnetic properties is studied, using scanning electron microscopy (SEM), X-ray diffraction (XRD), and alternating gradient force magnetometry (AGFM) techniques. SEM studies revealed a granular and compact structure of the surface of the electrodeposited Ni layers, and the variation of film roughness with bath pH is established. XRD analysis gives evidence of strongly textured Ni films along the (111) direction, with the face-centered cubic (fcc) structure for all baths pH. Magnetic properties such as coercivity, remanence, saturation magnetization, and squareness showed strong dependence on the baths pH and crystallite size. High coercivity was attributed to the presence of the small crystallite size of deposits. The properties of the deposit are greatly influenced by the solution pH.