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[Display omitted] • Rapid co-deposition of dopamine and APTS was used to construct superhydrophilic membranes. • Superhydrophilic membrane had an effective oil repellency with underwater oil contact angle of ∼163.5°. • Superhydrophilic membrane has a fast gravity-driven filtration for oil-in-water emulsions with a separation efficiency of >99.9 % • Incorporation of Cu NPs and polydopamine enables the membranes with complete antibacterial activity. Substantial discharge of industrial oily wastewater calls for an efficient and sustainable treatment for resource recovery. Superwetting membranes offer a feasible approach to fractionate oil species and water from oily wastewater for addressing this technical challenge. In this study, we proposed a useful strategy for constructing a superhydrophilic membrane with superior antibacterial properties through rapid co-deposition of dopamine and 3-aminopropyltriethoxysilane (APTS) initiated by ammonium persulfate on the Cu nanoparticles-loaded porous PVDF substrate. The resultant superhydrophilic membrane yielded an underwater oil contact angle of 163.5°, enabling a fast and robust gravity-driven filtration for various oil-in-water emulsions with a separation efficiency of >99.9 %. Additionally, incorporating of Cu nanoparticles and polydopamine endowed the superhydrophilic membrane with superior antibacterial activity (100 % inhibition efficiency against Escherichia coli), and thereby remarkably enhancing the anti-biofouling performance. This study provides a viable approach to design high-performance membranes for separation of oil-in-water emulsions, with promising applications in the industrial and environmental sectors. [ABSTRACT FROM AUTHOR]

• Superhydrophobic PVDF membrane was fabricated by spray-coating of fluorinated SiO 2 NPs. • Superhydrophobic PVDF membrane had a water contact angle of 171.8 ± 1.1° and sliding angle of 1.69 ± 0.13°. • The modified PVDF membrane maintained stable superhydrophobicity under harsh conditions. • The prepared membrane has consistent separation efficiencies up to 99.88 ± 0.03% in water-in-oil emulsions over 40 cycles. • Scale-up fabrication of superhydrophobic PVDF membrane was successfully performed. Hydrophobic anti-wetting membranes have many applications, such as oily wastewater treatment via oil/water separation, desalination via membrane distillation, and carbon capture via gas-liquid membrane contactors. Herein, we used a simple and scalable method to fabricate robust superhydrophobic polyvinylidene fluoride (PVDF) based membranes by one-step spray-coating of fluorinated SiO 2 nanoparticles. The prepared PVDF membrane was systematically characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, X-ray photoelectron spectroscopy and contact angle measurements. The modified PVDF membrane had excellent superhydrophobicity with an extremely high water contact angle up to 171.8 ± 1.1° and a low sliding angle of 1.69 ± 0.13°, due to the fluorinated close-packed hydrophobic SiO 2 nanoparticles on the surface. The modified PVDF membrane maintained its relatively stable superhydrophobicity under various harsh conditions, i.e., exposure in hot water, NaOH and HCl, ultrasonication and high-speed flushing, indicating the superior robustness and stability. The prepared membrane also exhibited consistent separation efficiencies up to 99.88 ± 0.03% in water-in-oil emulsions, and superior recyclability and durability over 40 cycles. In addition, spray-coating showed its great promise in engineering various superhydrophobic surfaces on different substrates and excellent scalability in fabricating large-size membranes. This study demonstrates a facilely scalable spray-coating method for engineering robust superhydrophobic surfaces and membranes that can be potentially used for various gas, vapor and water/oil separations. [ABSTRACT FROM AUTHOR]