Electric field manipulation for deposition control in near-field electrospinning

Electrospinning is recognized as an efficient and versatile technique that has been widely used in nanoscale fiber fabrication. Electric field manipulation is one of the efficient ways to precisely control an electrospinning jet. While there have been several studies of the electric field manipulation effect on nanofiber deposition control, these works are limited to the control of a far-field electrospinning (FFES) jet to deposit in one dimension or to suppress the chaotic whipping mode to some extent. Few work has been done to control a near-field electrospinning (NFES) jet for deposition of complex patterns using electric field manipulation. To this end, we propose a novel design by adding a moving sharp-pin electrode beneath the plane collector. The sharp pin electrode is charged with a positive voltage and moved to redistribute the electric field for jet trajectory control, while the plane collector is kept stationary. The focusing of the electric field and the guiding effect of the jet trajectory due to the additional sharp-pin electrode are studied and demonstrated. Various parameters (voltage, electrode translation speed, and collection mechanism) are analyzed to experimentally study their effects on the fiber deposition control. It is demonstrated in the current work the feasibility of controlling a single fiber for deposition of complex patterns in near-field electrospinning by manipulating the electric field distribution.