Collagen‐Derived Nanoconfined Catalytic Membranes for Highly Efficient Water Remediation

Nanoconfined catalytic membranes (NCMs) are promising for advanced water treatment but often face trade-offs between permeability, stability, and catalytic efficiency. Here, the hierarchical architecture of collagen fiber networks (CFNs) is exploited to develop robust, efficient, and sustainable collagen-derived NCMs. Mechanical nanofibrillation and tannic acid (TA) functionalization generate highly dispersed fibrils and interconnected nanochannels that enhance water transport and active-site accessibility. TA further directs mineralization of Fe₃O₄ nanocatalysts and accelerates H₂O₂ activation, while the hierarchical porous structure promotes efficient utilization of reactive oxygen species. The resulting TA/Fe@CFN membranes exhibit high water permeance (2274.8 LMH bar^-1) and achieve 98.2% tetracycline removal under flow-through conditions, along with efficient removal of antibiotic-resistant bacteria and genes in real medical wastewater. Mechanistic studies reveal that nanoconfinement is vital to the accelerated catalytic kinetics and enhanced Fenton activity. Life cycle and economic analyses further demonstrate that TA/Fe@CFN is a green and cost-effective alternative to conventional polymeric membranes. This work establishes a high-performance, environmentally compatible platform for wastewater purification and highlights the broad potential of upcycling animal byproducts into multifunctional materials for circular water technologies.