Interfacial\nEngineering of Bi<sub>3</sub>O<sub>4</sub>Br/MXene Schottky Junctions\nfor Enhanced Adsorption Enrichment and\nPhotocatalytic Regeneration Active Sites for Water Decontamination

Photocatalytic technology still faces\nsignificant challenges\nin\nremoving trace concentrations of organic pollutants from wastewater.\nIn this study, we synthesized Bi<sub>3</sub>O<sub>4</sub>Br/MXene\n(BOB/M) with a Schottky junction structure, enhancing the continuous\nadsorption active site regeneration after visible light irradiation\nfor organic pollutant removal. Notably, the adsorption removal rate\nof tetracycline by BOB/M under light irradiation increased by 29.2%\ncompared to dark conditions, indicating that light exposure regenerates\nthe adsorption active sites. This improvement is mainly attributed\nto the introduction of MXene, which promotes the formation of reactive\nspecies, thereby accelerating the regeneration of the adsorption sites.\nThe composite exhibits superior adsorption performance for electropositive\npollutant molecules compared with neutral and negatively charged ones.\nMoreover, through a series of experiments and analytical characterizations,\nwe identified superoxide radicals as the primary reactive oxygen species\nresponsible for the degradation of tetracycline, facilitating the\nregeneration of adsorption sites. Furthermore, the BOB/M material\nexhibits excellent anti-interference capacities and stability. This\nstudy provides a novel approach for designing photocatalysts that\nare effective at targeting trace levels of contaminants.