Engineering surface chemistry to precisely control interfacial interactions is crucial for fabricating superior antifouling coatings and separation membranes. Here, we present a hydrophobic chain engineering strategy to regulate membrane surface at a molecular scale. Hydrophilic phytic acid and hydrophobic perfluorocarboxylic acids are sequentially assembled on a graphene oxide membrane to form an amphiphilic surface. The surface energy is reduced by the introduction of the perfluoroalkyl chains while the surface hydration can be tuned by changing the hydrophobic chain length, thus synergistically optimizing both fouling-resistance and fouling-release properties. It is found that the surface hydration capacity changes nonlinearly as the perfluoroalkyl chain length increases from C4 to C10, reaching the highest at C6 as a result of the more uniform water orientation as demonstrated by molecular dynamics simulations. The as-prepared membrane exhibits superior antifouling efficacy (flux decline ratio <10%, flux recovery ratio ~100%) even at high permeance (~620 L m−2 h−1 bar−1) for oil-water separation.

Electro-Fenton is a widely used electrochemical advanced oxidation process for the treatment of refractory organic pollutants, in which O 2 input is required to generate hydrogen peroxide. The aeration mode directly affects the dissolution and stability of O 2 bubbles in the solution, thus the rate of degradation. Herein, membrane aeration was introduced to the electro-Fenton degradation of ciprofloxacin in which O 2 was dispersed into the liquid phase in the form of microbubbles through the ceramic membrane. Microbubbles can greatly improve the gas−liquid mass transfer efficiency of unit volume O 2 to obtain an ultrahigh concentration of dissolved O 2 up to 46 mg/L, thus improving the reaction rate. The effects of aeration mode, applied current, membrane aperture, aeration rate, and ciprofloxacin concentration on degradation rate were studied. Compared with the conventional electro-Fenton process using plastic pipe aeration, the membrane aeration-enhanced electro-Fenton (MAEF) system achieved a significant improvement in the degradation rate, and the reaction time required to achieve a 97% degradation ratio was remarkably reduced from 4 h to 10 min. Membrane aeration is an efficient approach to facilitating heterogeneous catalysis reactions involving the gas phase.

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