UC Irvine

Carbon nanofiber has been gaining traction due to its broad application. Nanofibers have been successfully produced by various fabrication method, such as extrusion or hot-wire drawing. Shortcomings of these methods, such as low-efficient and, high-cost, preventing it from becoming a scalable manufacture process. Alternatively, electrospinning is a low-cost and high-efficient technique capable of manufacturing larger quantities of fibers in a relatively short period. Even though, the conventional electrospinning method, far-field electrospinning has become commercialized for production of large bundles of nanofiber, it is incapable of producing ordered and orientated fibers. Unfortunately, many need the precise control of the fiber deposition which is difficult with the far-field electrospinning. This limitation was resolved using near-field electrospinning, which could fabricate the fibers in a controllable, economical and rapid way.

Before this research, various near-field electrospinning apparatuses were developed to enhance the controllability of the fiber deposition. For example, our lab (UCI Bio-MEMS Lab) has developed a new electromechanical spinning (EMS) technology. Compared with the previous electrospinning method, the precise deposition of single suspended fibers has been achieved, but scalability and throughput still need to be improved.

Therefore, we built a novel new electrospinning system inspired by the existing EMS and conventional far-field electrospinning system. The system has successfully produced the aligned nanofibers with a diameter on the magnitude of nanometer and micrometer. More importantly, this new approach could generate hundreds of nanofibers in less than a minute. The process parameters of this new system, including the applied voltage, stage speed of the needle, working distance between the needle and collector and the rotation speed of the drum, on fiber diameter and fiber alignment are reported in this thesis. This new method of near-field electrospinning has outperformed the existing electrospinning techniques as a potential for scalable nanofiber manufacturing.