Biomimetic hydrophilization engineering on membrane surface for highly-efficient water purification

The polymeric membrane has been widely used for wastewater remediation due to its low energy consumption and benign mechanical properties . Its inherent hydrophobicity leads to non-ideal performances during energy-/environmental-related processes, the surface manipulation strategies towards much hydrophilicity are urgently to be developed for practical usages. Herein, a biomimetic coating is realized on porous membrane surface for surface hydrophilization via facilely combining mussel-inspired chemistry with polyphenol-based surface engineering. The as-deposited eco-friendly biomimetic coating greatly enhanced membrane hydrophilicity, infiltration , and antifouling potential via one-step co-depositing dopamine and plant-derived tannic acid. As a demonstration, water remediations of oil-in-water emulsion and simulated protein wastewater were conducted, leading to highly-efficient separation performances and antifouling potential. The initial flux of modified microfiltration membrane for the cycling oil-in-water emulsion separation could reach ca. 2100 L m −2  h −1 with oil rejection of >99.6%; the corresponding ultrafiltration membrane exhibited benign protein interception performance (BSA rejection of 93% with water flux of 490 L m −2  h −1 ) and antifouling ability (80% enhancement). Most importantly, the novel modified membrane demonstrates the ultra-stability under harsh bending and leaching tests. The facile biomimetic surface hydrophilization engineering will greatly power the membrane-based water environment remediation and stimulate the rapid advances in control release, anti-corrosion coating and other fields highly depending on surface properties.