| Abstract
| - Nanocables with a radial metal−semiconductor heterostructure have recently been prepared by electrochemicaldeposition inside metal nanotubes. First, a bare nanoporous polycarbonate track-etched membrane is coateduniformly with a metal film by electroless deposition. The film forms a working electrode for further depositionof a semiconductor layer that grows radially inside the nanopore when the deposition rate is slow. We proposea new physical model for the nanocable synthesis and study the effects of the deposited species concentration,potential-dependent reaction rate, and nanopore dimensions on the electrochemical deposition. The probleminvolves both axial diffusion through the nanopore and radial transport to the nanopore surface, with a surfacereaction rate that depends on the axial position and the time. This is so because the radial potential dropacross the deposited semiconductor layer changes with the layer thickness through the nanopore. Since axiallyuniform nanocables are needed for most applications, we consider the relative role of reaction and axialdiffusion rates on the deposition process. However, in those cases where partial, empty-core deposition shouldbe desirable (e.g., for producing conical nanopores to be used in single nanoparticle detection), we giveconditions where asymmetric geometries can be experimentally realized.
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