One-Step Electrospinning To Produce Nonsolvent-Induced Macroporous Fibers with Ultrahigh Oil Adsorption Capability

The demand for an efficient method to clean spreading oil on water is increasingly urgent due to the frequent occurrence of oil spill accidents around the world. In this work, we used a simple one-step electrospinning technique without the requirement of post-treatments to fabricate polystyrene (PS) fibrous sorbents that show exceptional oil adsorption capability. This method involves the dissolution of PS in cosolvents composed of a good solvent, chlorobenzene, and a nonsolvent, DMSO, for electrospinning. The size of the PS fibers electrospun from the cosolvents is rather uniform, and more importantly, the nonsolvent induces a highly porous structure throughout the fibers during the drying process. The porous structure imparts superhydrophobic surface to the fibrous mats, and thus the fibers can selectively adsorb oils while repel water. Furthermore, both the capacity and the rate of oil adsorption are greatly enhanced for the sorbents made of the porous fibers, in contrast to pore-free ones. The oil adsorption capability is closely dependent on the fiber size and the porous morphology, which can be simply controlled by adjusting the compositions of polymer solutions.