Template-assisted electrodeposition of metals: A method for determining the fraction of active nanopores

Template-assisted electrodeposition is a versatile technique for preparing metal nanostructures, e.g. nanowires and nanotubes, in anodic aluminium oxide (AAO) templates with cylindrical channels. However, the fraction of pores in which the electrochemical process occurs is not known in advance, which makes coulometric control of the deposition process nontrivial. In this paper, we propose a simple method for determining the fraction of active nanopores, i.e., pores in which metal is deposited. This is based on the analysis of current transients registered during templated electrodeposition. The developed method makes it possible to estimate the density of deposited nanowires and their average length by coulometric control without using scanning electron microscopy.