Catalytic membranes assembled by Co–Fe Prussian blue analogues functionalized graphene oxide nanosheets for rapid removal of contaminants

Abstract

The catalytic membrane, combining confinement effect with advanced oxidation processes, exhibits great potential as an efficient technology for removing contaminants and mitigating membrane fouling. Herein, the Prussian blue analogues (PBAs) functionalized graphene oxide (GO) membranes, referred as PGMs, was successfully fabricated. It exhibited a package-like confined structure where Co–Fe PBAs were encapsulated within interconnected GO nanosheets. The surface properties, internal structure as well as the catalytic performance of PGMs were controlled by adjusting the amount of Co–Fe PBAs anchored on GO nanosheets. The designed PGM as efficient peroxymonosulfate activator exhibited exceptional catalytic performance, achieving complete removal of bisphenol A (BPA) with a retention time of 31 ms. The corresponding first-order rate constant was 6000 min−1, which surpassed conventional batch system by four orders of magnitude (0.2194 min−1). Moreover, the redox cycle involving Fe2+ and Co3+, coupled with the effective suppression of ion leaching from Co–Fe PBAs nanoparticles (<10 μg/L) through GO protective layers, ensured the stable catalytic performance of PGM over 144 h. This study employs a novel approach to confine catalytic nanoparticles within two-dimensional nanosheets, demonstrating the potential applications of the resulting confined membrane in water treatment.