Control of an electrospinning jet using electric focusing and jet-steering fields

Electrospinning can be used to deposit a wide variety of nanoscale polymeric fibers that have electrical, optical, or biological properties of interest. While there have been many studies of material properties, the typical deposited nanofibers are in the form of a randomly oriented mat. The authors are interested in forming functional devices utilizing the properties of the individual nanofibers. To this end they have used electric fields to both confine and steer an electrospun polymer jet for controlled deposition of functional materials. They have used an electrode between the electrospinning tip and grounded sample to suppress the chaotic whipping mode, thereby focusing the characteristic spot size of the deposited fibers to a smaller diameter. The same electrode setup was then modified to produce a time-varying steering field. Using this system, they have deposited isolated electrospun polymer fibers in a controlled fashion. They have also demonstrated that it is possible to terminate electrospun fibers using the modulated electric field. (c) 2006 American Vacuum Society.