Electrodeposited magnetic nanowires: arrays, field-induced assembly, and surface functionalization

Electrodeposition into nanoporous templates provides a means of fabricating large quantities of magnetic nanowires with diameters in the range 5 nm-10 mum, and lengths up to 60 mum. Several recent developments in nanoporous templates and Ni nanowires are described. Templates formed by alpha-particle irradiation of single-crystal mica are shown to contain diamond-shaped nanopores with uniform size and orientation. Ni prisms deposited in these templates show anisotropic magnetic properties along all three axes of the prisms. The manipulation of isolated Ni nanowires in a variety of suspensions, and a quantitative analysis of the dynamics of the self-assembly of these nanowires under the control of external magnetic fields is described. Surface functionalization with porphyrin molecules yields fluorescent Ni nanowires that have potential for use in biotechnology and other applications. (C) 2002 Elsevier Science B.V. All rights reserved.