Bio-inspired superhydrophobic fiber membrane for oil-water separation and non-destructive transport of liquids in corrosive environments.

Conventional polymer separation membranes or coatings suffer from poor separation performance and serious failure in highly corrosive environments, due to their low chemical and mechanical stability. Herein, a simple electrospraying and electrospinning strategy was used to prepare flexible superhydrophobic carbon fiber membranes (FSCFM). The wettability of FSCFM was improved by forming a lotus leaf-like hierarchical rough structure on its surface. The FSCFM exhibited an excellent permeation flux of immiscible oil-water mixtures (up to 15,800 L m−2 h−1) and water-in-oil emulsions (over 5500 L m−2 h−1), while the separation efficiencies were always kept at more than 99 % after 25 consecutive separations. Even in corrosive environments, its separation performance did not show any degradation. Notably, except for recovering floating oil under external driving forces with excellent cyclic stabilities, FSCFM was also able to transport various corrosive solutions with high efficiencies (99.9 %). After multiple mechanical damages and bending cycles, the FSCFM remained superhydrophobic. It could also maintain its repellency in strong acids/bases, high salt solutions and even under high-temperature environments (94.5 °C). These superior properties make it a strong candidate for oil-water mixture/emulsion separation and non-destructive transport of highly corrosive fluids. [Display omitted] • Flexible superhydrophobic carbon fiber with a lotus leaf structure. • Excellent separation capability of oil-water mixtures and emulsions. • The separation performance in highly corrosive environments remains unchanged. • Excellent mechanochemical robustness and multifunctionality were obtained. [ABSTRACT FROM AUTHOR]