Methods for the preparation of long, dimensionally uniform, metallic
nanowires that are removable from the surface on which they are
synthesized. The methods include the selective electrodeposition of metal
nanowires at step edges present on a stepped surface, such as graphite,
from an aqueous solution containing a metal or metal oxide. Where a metal
oxide is first deposited, the metal oxide nanowires are reduced via a gas
phase reduction at elevated temperatures to metal nanowires.
Alternatively, beaded or hybrid nanowires comprising a metal A into which
nanoparticles of a metal B have been inserted may be prepared by first
electrodepositing nanoparticles of metal B selectively along step edges
of a stepped surface, capping these nanoparticles with a molecular layer
of an organic ligand, selectivley electrodepositing nanowire segments of
metal A between nanoparticles of metal B and then heating the surface of
the hybrid nanowire under reducing conditions to remove the ligand layer.
In all three methods, the nanowires may be removed from the stepped
surface by embedding the wires in a polymer film, and then peeling this
film containing the embedded wires off of the stepped surface.