Overview

• The interfacial polymer cross-linking approach forms 3 μm-thick membranes with stable covalent networks.
• The membranes feature a quasi-ordered reticular structure with 1.8–5.4 Å cavities for angstrom-scale ion sieving.
• The design achieves high ion selectivity without sacrificing permeability, overcoming a long-standing performance trade-off.
• Adjustable cross-linking times and agent types allow precise tuning of membrane thickness and pore morphology.
• The fabrication method aligns with existing industrial processes for water purification and chemical separations.