A system for synthesizing nanostructures using chemical vapor deposition (CVD) is provided. The system includes a housing, a porous substrate within the housing, and on a downstream surface of the substrate, a plurality of catalyst particles from which nanostructures can be synthesized upon interaction with a reaction gas moving through the porous substrate. Electrodes may be provided to generate an electric field to support the nanostructures during growth. A method for synthesizing extended length nanostructures is also provided. The nanostructures are useful as heat conductors, heat sinks, windings for electric motors, solenoid, transformers, for making fabric, protective armor, as well as other applications.