范德华S型异质结赋予快速电荷转移助力光催化活性提升OA

The rational design of efficient step-scheme(S-scheme)heterojunctions is a significant breakthrough in photocatalysis,holding great potential to enhance eco-friendly environmental restoration and energy conversion technologies.However,conventional S-scheme heterojunctions frequently suffer from lattice mismatch issues,which severely compromise the efficacy of built-in electric fields in charge separation.To address this limitation,we developed an innovative in situ deposition strategy to construct van der Waals S-scheme heterojunctions within Bi2O2S-BiOBr composites.This approach effectively mitigates lattice mismatch and ensures intimate interfacial contact,enabling the formation of a strong internal electric field that facilitates efficient carrier migration.The Bi2O2S-BiOBr composites exhibit an extended light absorption range exceeding 700 nm,allowing for broad-spectrum photocatalytic activity.Under Xenon lamp irradiation,the Bi2O2S-BiOBr composites demonstrated outstanding photocatalytic efficiency in the degradation of ciprofloxacin(CIP).Notably,the 20%Bi2O2S-BiOBr composite achieved 93%CIP removal within 15 min,outperforming all other tested composites.The notable enhancement in performance stems from the van der Waals S-scheme heterojunction,which facilitates highly efficient separation of photogenerated carriers.This work provides valuable insights for the strategic design of advanced van der Waals heterostructures with S-scheme charge transfer mechanisms.