Improving Electrospinning Technique for Better Alignment of Carbon Nanofibers
- Giulia Canton, Graduate Student, University of California Irvine
- Swati Sharma, Graduate Student, University of California Irvine
- Lawrence Kulinsky, Senior Researcher , University of California Irvine
- Marc Madou, Professor of Mechanical and Aerospace Engineering, University of California Irvine
Carbon nanofibers are quasi 1-D structures with a thickness in the order of nanometer (10-9m) and mainly composed of glassy carbon. They are characterized by a high surface to volume ratio, which is a great advantage for highly sensitive sensors applications. Commonly, carbon nanofibers are fabricated via Electrospinning of a polymer precursor and the subsequent pyrolysis of the produced fibers. Electrospinning is an effective yet simple and inexpesive way to form the nanofibers. Two setup of electrospinning techniques were investigated: the more traditional Far-Field Electrospinning (FFES) and the newly developed Near-Field Electrospinning (NFES). In FFES a strong electric field is applied to a polymer solution, which induces the formation of a continuous nanofiber jet. This technique enables an high fibers throughput, however, as the name said, the distance between the polymer source and the target is “far” (~10 cm), leading to a random deposition. One of the most recent efforts to align the fibers is by investigating the magnetic field effect on electrospinning (Hall Effect). Even if many efforts has been done, it is still hard to control FFES fiber deposition. Recently, NFES setup is used to overcome this issue, by reducing the distance of the needle to the target (~0.5 mm). Through NFES alignment of fibers are obtained. As the objective for aligned fibers have been achieved, several parameters (e.g. voltage, polymer ink properties, nozzle diameter, magnetic field interaction) are investigated for the NFES to get thinner fibers.