Photoconductive CdSe Nanowire Arrays, Serpentines, and Loops Formed by Electrodeposition on Self-Organized Carbon Nanotubes

Abstract

Semiconducting nanowires frequently have enhanced properties and unique functionality compared to their bulk counterparts. Controlling the geometry of nanowires is crucial for their integration into nanoscale devices because the shape of a device component can dictate its functionality, such as in the case of a mechanical spring or an antenna. We demonstrate a novel synthetic method for making polycrystalline CdSe nanowires with controlled geometries by using self-organized single-walled carbon nanotubes as a template for the selective electrodeposition of nanowires. Nanowires of up to hundreds of micrometers in length are formed as high-density straight arrays, as well as in the shape of serpentines and loops. These nanowires exhibit significant photoluminescence and photoconductivity applicable to photodetectors and respond to illumination up to 2 orders of magnitude faster than single crystalline CdSe.