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 & BULL; and 1O2 are demonstrated to be the main active species, which synergistically contribute to the PMS-driven organic degradation.

Automated summary

Membrane catalysis using two-dimensional materials has shown significant progress in peroxymonosulfate-based processes. In this study, large-scale 2D blade-shaped CoFe Prussian blue analog (PBA) sheets were fabricated using a bottom-up strategy. These sheets were then assembled into a free-standing 2D membrane, which exhibited excellent wetting properties and superior catalytic performance for norfloxacin degradation. The main active species were identified as SO4• and 1O2, which contributed synergistically to the PMS-driven organic degradation.