SPR effect and internal electric field in Pt@BiOBr/(001)-TiO2 S-scheme heterojunction for visible-light-driven photocatalytic degradation of tetracycline hydrochloride and dyes

The photocatalytic destruction of contaminants in water, such as antibiotics and dyes, has emerged as a hot topic in environmental treatment. The 2D/2D BiOBr/(001)-TiO 2 S-scheme heterojunction , decorated with Pt, was fabricated through in-situ construction and photochemical deposition techniques and utilized to effectively eliminate tetracycline hydrochloride , rhodamine B , and methyl orange. 0.3 wt% has the highest degradation activity when exposed to visible light , and all TC-HCL degradation can be accomplished in 5 min. The photodegradation rate constants of BiOBr and BiOBr/(001)-TiO 2 are 15.3 and 6.3 times higher, respectively. Its satisfactory photocatalytic performance can be attributed to efficient interfacial charge separation, surface plasmon resonance (SPR) effect-induced broadening of the light absorption range, and enhanced migration and separation of photogenerated electron-hole pairs, as well as the formation of an S-scheme heterojunction with strong redox ability. Meanwhile, the larger heterogeneous interface of 2D/2D nanostructures offers efficient charge transfer channels and more reactive sites. Experiments involving electron spin resonance (ESR) and free radical capture demonstrated the generation of not only h + and O 2 − , but also more potent OH radicals. Furthermore, an effective S-scheme heterojunction carrier migration and degradation pathway was proposed based on the experimental results. This study proposes a novel concept for the production of S-scheme heterojunctions photocatalysts that are effective for wastewater pollutant degradation.