| Abstract
| - A general method is described for the electrodeposition of long (>500 μm) nanowires composed of noble orcoinage metals including nickel, copper, silver, and gold. Nanowires of these metals, with diameters in therange from 60 to 750 nm, were obtained by electrochemical step edge decoration (ESED), the selectiveelectrodeposition of metal at step edges. Nanowire growth by ESED was accomplished on highly orientedpyrolytic graphite surfaces by applying three voltage pulses in succession: An oxidizing “activation” pulse,a large amplitude, reducing “nucleation” pulse, and a small amplitude reducing “growth” pulse. The activationpulse potential was optimized to oxidize step edges on the graphite surface just prior to deposition. Thenucleation pulse had an overpotential for metal deposition of between −150 and −500 mV and a duration of5−100 ms. The growth pulse had a small deposition overpotential of less than −100 mV. Nanowire growthwas characterized by a time-independent deposition current, and consequently, the nanowire radius wasproportional to the square root of the deposition time in accordance with the expected growth law.
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