Tear-film-inspired interfacial polymerization engineering nanofiltration membrane architecture for highly efficient antibiotic desalination

The finely tuned architecture of nanofiltration (NF) membranes with confined transport/sieving channels is crucial for improving the separation capability for diverse molecular/ion applications. However, the fine microstructural regulation of NF membranes with facile fabrication conditions and low cost is still challenging. Herein, inspired by the homeostatic liquid phase of tear film maintained by phosphate hydrogen bonds, we report an inorganic phosphate-mediated interfacial polymerization strategy to regulate the microstructure of NF membranes, which is compatible with current commercial membrane manufacturing methods. Inorganic phosphate groups were verified to effectively control the diffusion of aqueous-phase monomers via hydrogen bonding. The synthesized NF membranes with a well-tuned architecture show excellent antibiotic desalination performance (rifamycin/NaCl selectivity of 117.2) with high water permeance, exceeding that of state-of-the-art nanofiltration membranes. Moreover, the tear film-inspired phosphate-mediated interfacial polymerization technique exhibited good universality in the fabrication of advanced membranes with different monomers.