Prussian Blue/Cellulose Acetate Thin Film Composite Nanofiltration Membrane for Molecular Sieving and Catalytic Fouling Resistance

Nanofiltration (NF) membranes as high selective separators are appealing for molecular sieving, which still remains a great challenge for the mixed dyes with same charge. In this study, cellulose acetate (CA) membranes were firstly aminated by ethylene imine polymer (PEI), and then the thin film of metal organic frameworks (MOFs) were constructed onto aminated CA membrane through forward-diffusion, slow crystallization and in situ growth of FeCo-Prussian blue (FeCo-PB) crystallization layers. The designed PB@CA composite NF membrane shows an ideal rejection for Congo red (CR)/methyl orange (MO) mixture solution, with 99.7%±0.2% for CR and 33.5%±2% for MO. In addition, the composite NF membrane demonstrated good efficiency for photocatalytic degradation of organic fouling (permeability recovery ratio was up to 92%) due to the active FeCo-PB micro-cubes. Thus, this work provides a practical strategy to prepare MOFs mediated thin film composite nanofiltration membrane for precise molecular sieving and catalytic antifouling performances.