Freestanding catalytic membranes assembled from blade-shaped Prussian blue analog sheets for flow-through degradation of antibiotic pollutants

Membrane catalysis is a frontier technology for effectively removing organic containments, and burgeoning membranes assembled from two-dimensional (2D) materials have significantly flourished in peroxymonosulfate (PMS)-based catalytic membrane processes. Here, a bottom-up strategy based on restricting CoFe Prussian blue analog (PBA) crystal growth in one direction is used to fabricate large-scale 2D blade-shaped PBA sheets, whose radial size and thickness can be adjusted by the precursor ion ratio (CoII/FeII). The stripe CoFe PBA sheets can directly serve as building blocks and are simply assembled into a free-standing 2D membrane by interweaving assembly. The assembled CoFe PBA catalytic membrane possesses excellent wetting properties, guaranteeing an unimpeded mass transfer process, which leads to a superior instantaneous catalytic performance for the antibiotic norfloxacin during the continuous and flow-through membrane catalytic process. SO4•− and 1O2 are demonstrated to be the main active species, which synergistically contribute to the PMS-driven organic degradation.