Alignment of Polymeric Nanofibers Using a Filtering Effect

One-dimensional nanostructures that play an important role as ideal building blocks for hierarchical assemblies, such as nanowires, nanofibers, and nanotubes, have attracted much attention because of their significance for fundamental investigations and their peculiar electrical, optical, and mechanical properties. In this work, by adding auxiliary parallel electrodes to a previously known electro-spinning process, we have developed an electro-spinning technology that can achieve the spatial alignment of nanofibers on various types of electrodes. The auxiliary electrodes played an important role as a filter, because any disordered nanofibers that can potentially disrupt the orientation were deposited on them. In addition to their filtering capability, the auxiliary parallel electrodes elongated any nonfiltered nanofibers into a long and straight configuration. Using our method, we have achieved better fiber alignment without the aid of elaborate controls for the flow rate or deposition time.