Construction of dual-heterogeneous membrane surface via nanosphere-mediated surface segregation for oil-water separation

The rational design of chemical-physical/geometric structures of membrane surface is the key for fabricating antifouling oil-water separation membranes. Herein, we propose a nanosphere-mediated surface segregation strategy to construct dual-heterogeneous antifouling membranes. The casting solution employs Pluronic F127 covalently grafted with hexafluorobutyl methacrylate (F127-F) as the surface segregation agent, while TA-APTES nanospheres (TAP NPs) are introduced in the coagulation bath as the crosslinking agent. During the NIPS process, the hydrogen bonding interactions between TAP NPs and F127-F promote the in-situ self-assembly of a dual-heterogeneous surface with controllable physical topology and hydrophilic-low surface energy composition. The resulting oil-water separation membrane achieves a pure water permeance of 543.17 ​L ​m −2 ​h −1 bar −1 , along with an ultralow permeance decline ratio of 0.34 ​% and a 100 ​% flux recovery ratio. Besides, the membrane displays excellent self-cleaning capability against crude oil.