A promising inorganic-organic Z-scheme photocatalyst Ag3PO4/PDI supermolecule with enhanced photoactivity and photostability for environmental remediation

Silver orthophosphate (Ag 3 PO 4 ) based semiconductor photocatalysis have been widely investigated for environmental purification due to its strong oxidation ability. Yet, its poor photostability and low photoactivity hamper its extensive applications. Here, an inorganic-organic Z-scheme photocatalytic system for antibiotic degradation demonstrated high photoactivity and stability through the use of Ag 3 PO 4 /Perylene diimide organic supermolecule (PDIsm). The apparent rate constant of tetracycline hydrochloride (TC-H) degradation with Ag 3 PO 4 /PDIsm was 1.5 times that of Ag 3 PO 4 and 8 times that of PDIsm. The photocatalytic activity of Ag 3 PO 4 /PDIsm toward TC-H still kept 65 % after four reuses, while pure Ag 3 PO 4 only kept 22 %. We revealed that this high photoactivity and photostability arisen from the efficient carriers separation and the formation of direct Z-scheme junction. Importantly, this Z-scheme electron transfer pathway was confirmed by thorough experimental study and density functional theory (DFT) calculation. This work demonstrated the significant potential of Ag 3 PO 4 -based inorganic-organic Z-scheme photocatalyst in environmental remediation.