PREPARATION OF ACICULAR IRON NANOPARTICLES BY THE REDUCTION OF FERROUS SALT IN THE PRESENCE OF TUBULAR LECITHIN ASSEMBLIES

Ferromagnetic alpha-Fe particles were prepared by reduction of Fe2+ in the presence of tubular lecithin assemblies found in lecithin/cyclohe xane/water association colloids. The particles consisted of both large single- and multi-domain acicular rods, 0.25-5 mu m in length with a length to width ratio of at least 6:1, encapsulated in lecithin. The c oercivity depended on the reaction medium and ranged from 7 to 131 Oe. The highest coercivity particles were obtained in the cyclohexane-ric h region of the ternary phase diagram. (C) 1996 American Institute of Physics.