Reticular nickel microwires with assembled nanostructures: Synthesis, magnetism and catalysis for the growth of carbon nanotubes

Reticular nickel microwires assembled from different-shaped building blocks are fabricated by a simple, one-pot method in the absence of any surfactants or external magnetic field. The synthetic process involves the chemical reduction of a nickel complex with hydrazine under controlled reaction conditions. Our strategy focuses on the modulation of the reaction rate to control the shape of the subunits and their spontaneous assembly behavior, which avoids the need for surfactants or an external force. The nickel wires can be reproducibly created with the assistance of various complexants, such as citrate, tartrate, lactate, ethylenediamine, triethanolamine and diethanolamine, which proves the generality of this method. These nickel wires show variable magnetic properties and catalysis for the growth of carbon nanotubes in pyrolyzing acetone due to the nature of their microstructures. ((c) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)