Surfactant-Assisted Electrodeposition of CoFe-Barium Hexaferrite Nanocomposite Thin Films

Abstract

The influences of anionic sodium dodecylsulfate (SDS) and cationic Hexadecyltrimethylammonium bromide (HTAB) surfactants on the incorporation and distribution of barium hexaferrite nanoparticles in the electrodeposited CoFe-BaFe₁₂O₁₉ composite thin films were studied. Sulphate bathes with natural pH containing 0 to 2 g/L surfactants were used for electroplating at room temperature. Field emission scanning electron microscopy (FE-SEM) and energy dispersive spectroscopy (EDS) from the surface of the deposited films, together with X-ray diffraction analysis were applied to confirm codeposition of the iron and cobalt, as well as incorporation of the nanoparticles. The results showed that the amounts of hexaferrite particles in the deposits were initially increased by increasing the concentrations of both surfactants in the electrolyte and reduced by further additions of the surfactants. The optimum values of surfactants were 1 and 0.5 g/L for SDS and HTAB, respectively. The highest amount of the barium hexaferrite in the deposits was 12 wt% which was achieved by using an electrolyte containing 0.5 g/L HTAB surfactant. Composition of the film's matrix was also changed by varying the amounts of the surfactants. The variation of the iron content of the film's matrix appeared to follow a trend similar to that of the amount of the particle's incorporation. The films deposited from electrolytes containing HTAB showed coarser morphologies compared to those obtained from bathes without surfactant or containing SDS.