One-step synthesis of phosphorus/oxygen co-doped g-C3N4/anatase TiO2 Z-scheme photocatalyst for significantly enhanced visible-light photocatalysis degradation of enrofloxacin.

Anatase TiO2 nanoparticles coated with P and O co-doped g-C3N4 were prepared via a single-step procedure. The resulting POCN/anatase TiO2 demonstrated remarkable performance in the degradation of enrofloxacin (ENFX). The photocatalytic activity of this heterojunction was 28.9 and 3.71 times better than that of the CN and anatase TiO2, respectively. The microtopography of the POCN/anatase TiO2 was revealed in this study. Co-doping with P and O increased the visible light adsorption capacity of the g-C3N4, whereas the anatase TiO2 nanoparticles enhanced the adsorption properties of the ENFX and the separation of the photoinduced carriers of the POCN/anatase TiO2. The O2·- and h+ were the main reactive oxidative species in the photocatalytic degradation of ENFX. The results of the detection of H2O2 and ESR confirmed that POCN/anatase TiO2 was a type Z-scheme photocatalyst. Finally, the ENFX degradation pathways were estimated through the detection of by-products.