One-pot construction of highly efficient TaON/BiO/S-BiOCl ternary photocatalysts: Simultaneously integrating type-Ⅰ with Z-scheme junctions for improved visible light-driven removal of organic pollutants.

Bismuth oxychloride (BiOCl) has appeared as a popular candidate in photocatalysis field but is plagued by its poor visible light harvesting and low carriers-flow steering inherited from wide band gap. Integration of doping and heterojunction engineering into the bulk has proven to be an optimal and generally applied method for enabling excellent photocatalytic activity. Nevertheless, the previous reported BiOCl-based photocatalysts fabricated by the above strategies are still suffered from harsh synthesis process, poor interface stability and narrow application area. Here, we introduce a facile one-pot hydrothermal strategy to achieve in-situ growth of TaON as a medium on the surface of BiO and S-doped BiOCl (denoted as S-BiOCl) for constructing ternary TaON/BiO/S-BiOCl heterostructures, which were obtained by the simultaneous coprecipitation and ripening process. Current investigation suggests that such a unique TaON/BiO/S-BiOCl exhibits a relatively much higher photocatalytic activity for visible light-driven removal of rhodamine B (RhB), tetracycline (TC) and tetracycline hydrochloride (TC-HCl) than those of hybrid BiO/S-BiOCl and pristine S-BiOCl. It is ascribed to the synergetic effect on the introduction of S dopant level in BiOCl lattice as well as the construction of intimate double heterointerfaces among BiO, TaON and S-BiOCl, which endows the TaON/BiO/S-BiOCl photocatalysts with considerable advantages for highly elevating photocatalytic performances, such as the intensive optical absorption, high redox potential as well as high-efficient photocharge separation originated from type-I and Z-scheme pathways. This work delivers novel insights for design and one-pot preparation of high-active BiOX (X = Cl, Br and I)-based photocatalysts towards organic dye and antibiotic removal in the future research.