Continuous surface Z-Scheme and Schottky heterojunction Au/La2Ti2O7/Ag3PO4 catalyst with boosted charge separation through dual channels for excellent photocatalysis: Highlight influence factors regulation and catalytic system applicability

The efficient separation and transmission of photogenerated charges is crucial for photocatalysis. In this paper, a novel continuous surface Z-Scheme and Schottky heterojunction composite Au/La2Ti2O7/Ag3PO4 with dual heterointerface channels was constructed for the steering separation and transport of charges. Excitedly, the composites exhibited outstanding photocatalytic activity under natural sunlight toward the organic photodegradation in contrast to the latest published researches because of the synergism of Z-Scheme and Schottky heterojunction. And the wide applicability of this photocatalytic system was well verified with various cations/anions, solution pH, reaction temperature, water quality, and peroxydisulfate (PDS) addition. Simultaneously, the rapid charge transport pathway and its induced active substances were deduced from the analysis of structural characteristics of the composite. Furthermore, the degradation mechanism was proposed based on the analysis of organic molecules’ reaction sites calculated by density functional theory (DFT) and the degradation intermediates detected by HPLC/MS. Additionally, the toxicity of degradation products was significantly diminished, which can secure the aquatic environment safety of receiving water body. This work not only affords a strategy for efficient separation of photogenerated carriers, but also provides an efficient photocatalytic system for environmental remediation of refractory organic polluted wastewater under natural sunlight irradiation.