Anti-fouling ternary zwitterionic coating membrane with strong surface hydration and salt resistant for efficient long-term emulsion separation in high salinity marine environment

Membrane separation has been acknowledged as an advanced technology to handle the oil spills. However, most of the superhydrophilic/underwater superhydrophobic membranes currently applied for oil/water separation would lose their superwettability when exposed to salty marine environments, leading to serious membrane plugging and separation performance deterioration. Herein, inspired by seawater fish and mussels, a simple, green, and versatile one-step co-deposition strategy is proposed for fabricating a ternary zwitterionic coating with strong surface hydration on diverse membranes, showing excellent anti-fouling properties in high salinity environments, even in the saturated NaCl solution. Moreover, the modified membrane performs well in the long term when separating surfactant-stabilized oil-in-seawater emulsion and with impressive recyclability. The ternary zwitterionic coating membrane exhibits great potential in treating oily wastewater in marine.