Multifunctional nanofibrous membranes for highly efficient harsh environmental air filtration and oil–water separation

With the acceleration of the global industrialization process, the treatment of corrosive waste gas and oily wastewater in pharmaceutical, petrochemical and smelting fields still remains tremendous challenges. Herein, a robust polysulfonamide/polyacrylonitril@silica (PSA/PAN@SiO2) nanofibrous membrane with a hierarchical structure was successfully developed to deal with air filtration and oil–water separation under practical complex environments. In the process of air purification, the synergistic effect of multiple components could effectively surmount the conflict between pollution particle removal efficiency and pressure resistance. The air cleaning efficiency (PM0.3) of the PSA/PAN@SiO2 composite membranes could reach 99.05 ± 0.13 % at a low pressure drop of 30 ± 2 Pa. Due to the outstanding stability of PSA and SiO2, the composite membranes still possessed stable filtration performance in complex environments (strong acid, strong alkali and high temperature). Furthermore, PSA/PAN@SiO2 composite membranes with unique wettability (under oil superhydrophobicity and underwater superoleophobicity) could efficiently separate oil–water mixtures and emulsions. This multifunctional filtration membrane provides enormous application potential for the field of individual protection and environmental governance, even in complex environments.