FePt magnetic multilayers electrodeposited from non-aqueous liquids

FePt magnetic multilayers were pulse electrodeposited from the mixture of ammonium hexachloroplatinate and iron dichloride in ionic liquids based on glycol (EG) and 1-ethyl-3-methylimidazolium chloride (EMIC). The chelate effect and electrochemical behaviour of the EMIC with the ions were determined by ultraviolet-visible spectra and cyclic voltammetry respectively. The iron atomic content in the FePt films ranged from 0.4 to 81.0 at-% when deposition potentials changed from 1.0 to -2.0 V(Ag/AgCl) in electrodeposition system with the EG (50 mL), ammonium hexachloroplatinate (25 mM L-1), iron dichloride (175 mM L-1) and EMIC (25 mM L-1) at 393 K. Fe50Pt50 thin films with smooth surface (50 at-% iron layer in FePt film) and the multilayer cross-section were obtained. Fct structural FePt multilayer was obtained based on X-ray diffraction pattern. Magnetic hysteresis loops showed that the multilayer possessed a magnetic anisotropic behaviour.