Development of electrospun fiber mat from silk fibroin for air pollution capturing

Air pollution raised by particulate matter (PM) has drawn considerable attention because it is a serious threat to the public health. To protect human from inhaling PM, electrospun nanofibers were developed to be used as air filters due to their high surface area, lightweight and high strength. However, the most conventional air filters are made from synthetic polymers with limitation in disposal because of their poor degradability. In addition, they become non-disposable wastes after use. In this study, silk fibroin (SF) nanofibers prepared by electrospinning technique was applied as filter because of its biodegradable and environmental sustainability. Besides, silk is natural material which can be naturally degraded after disposal. Furthermore, the electrospinning parameters affecting on morphology fibers, including spinning rate and applied voltage were also studied. It was found that the diameter of fiber was decreased with respect to an increasing spinning rate from 0.4 mL/h to 1.4mL/h. The fiber diameter was significantly decreased with an increasing voltage from 12 kV to 16 kV. Moreover, it was also found that the spinning rate of 1.4 mL/h and voltage of 12 kV yielded the smallest fiber diameter which was around 130.40 ± 53.66 nm. With this spinning parameter, electrospun fiber mat showed PM_2.5 removal efficiency as 95.45 ± 1.56%, with quality factor of 0.89. Thus, silk nanofiber can be potentially used as green air filters in the future.