Anti-oil fouling poly(vinylidene fluoride) membrane with excellent underwater superoleophobicity and high-efficient photo-Fenton oxidation for oily water purification

Oil fouling makes serious trouble to the membranes for oil-in-water emulsion separation and purification. Here, an anti-oil fouling membrane was designed and constructed by loading 8-FeOOH nanorods and carbon quantum dots (CQDs) on the poly(vinylidene fluoride)/poly(2-hydroxyethyl methacrylate) blend membrane. The fabricated BM@(& beta;-FeOOH/CQDs) membrane can efficiently separate various oil-in-water emulsions. Furthermore, BM@(& beta;-FeOOH/CQDs) exhibits stable underwater superoleophobicity with an underwater oil contact angle (UWOCA) of 152.5 & PLUSMN; 1.1 degrees and a sliding angle (SA) of 2.2 & PLUSMN; 0.2 degrees, which is beneficial to prevent oil droplets from contacting and adhering to the separation porous surface. Moreover, BM@(& beta;-FeOOH/CQDs) has excellent photoFenton oxidation efficiency, which can photo-activate H2O2 to degrade oil droplets on the separation membrane. The flux recovery ratio of the membrane increases by 1.8 times when the photo-Fenton reaction was activated. This work provides an effective strategy for the engineering of anti-oil fouling membranes to purify oily wastewater.