Capillarity assisted interfacial reaction fabrication of spatially separated site-specific AgI/Fe3O4/Ag3PO4@GF for efficient photocatalytic reaction

High-efficient charge separation, excellent light absorption and sustainable recycling are critical for solar energy conversion over solid photocatalysts. Based on the capillarity assisted interfacial reaction, AgI and Ag3PO4 nanoparticles (NPs) were selectively deposited on diverse faces of Fe3O4 functionalized graphene film for fabrication of spatially separated site-specific Z-scheme silver iodide/ferroferric oxide/silver phosphate graphene film (AgI/Fe3O4/Ag3PO4@GF) composite. For the spatially separated site-specific photocatalyst, the Fe3O4@graphene film with planar structure is not only favorable to the light absorption of AgI and Ag3PO4 NPs on its surface but also facilitates its cyclic regeneration. The separated hetero-structure ensures well-steered transfer of photogenerated electrons from Ag3PO4 and holes from AgI to the Fe3O4 medium with concerted efforts from Z-scheme construction, which effectively reduce the photogenerated charge recombination. Profiting from its unique function and structure, the obtained AgI/Fe3O4/Ag3PO4@GF exhibits distinguished photocatalytic activity for methyl orange (99% removal rate in 30 min), bisphenol A (93% removal rate in 30 min), ciprofloxacin (93% removal rate in 160 min), disinfection (100% Escherichia coli (E. coli) inactivation) and remarkable recycling stabilities.