Thin films of metallic nickel with a thickness of the order of 20 nm have been prepared at the organic-aqueous interface at room temperature by the reaction of nickel cupferronate [Ni(C(6)H(5)N(2)O(2))(2)] in toluene medium and sodium borohydride (NaBH(4)) in aqueous medium. The films were characterized with transmission electron microscopy, scanning electron microscopy and atomic force microscopy. Thicker Ni films could be prepared by carrying out the reaction at the interface at 60 degrees C. The Ni nanofilms exhibit superparamagnetic behavior. (c) 2011 Elsevier Ltd. All rights reserved.