Structural properties of Co, Ni and Mo powders obtained by electrochemical deposition

Abstract

Magnetic thin films based on iron group elements (Fe, Co, Ni) are currently used in computer's hard disk drives and in MEMS, whereas electrodeposition is a suitable method to obtain these materials. The powders of metals and alloys were obtained by electrochemical deposition at constant current density using alkaline ammonium electrolyte which consist one, two or three different elements Co, Ni and Mo. Ni and Co are deposited anomalously. The Mo element cannot be obtained electrochemically from the aqueous solutions. Electrochemical deposition of this metal is induced by codeposited iron-group metals, Ni and Co, for instance. This study investigates the influence of electrochemical parameters on composition and properties of obtained powders. Based on the obtained experimental results, it could be concluded that the particle size of deposited powders and chemical composition are influenced by the chemical composition of the electrolyte, with changing the concentration ratio of ions of metallic salts as well as current density imposed. As a consequence, the changes in magnetic properties are obvious. The structure and morphology of powders were investigated by Scanning Electron Microscopy (SEM). For demonstration of mechanism of powder deposition Image ProPlus software for SEM microphotograph analysis was used. The values of individual objects as well as formed clusters of powders were measured by this technique. The chemical composition of the powders was determinate using Energy Dispersive X-ray (EDX) analysis. XRD results suggested that obtained powders were of amorphous structure.