S型异质结Al6Si2O13/BiOBr通过增强电荷转移效应实现高效稳定光催化降解三唑磷和敌敌畏农药OA

Amidst growing concerns regarding pesticide contamination,particularly within the realms of food,grains,and meat products,the quest for highly efficient and stable photocatalysts for pollutant degradation has become an imperative area of research.In this study,a novel S-scheme heterojunction photocatalyst,Al6Si2O13/BiOBr(ASO/BO)nanocomposites,was successfully synthesized to enhance charge transfer and improve the photocatalytic degradation of Triazophos(TAP)and Dichlorvos(DDVP),prevalent agricultural pollutants.Performance evaluation revealed that the 60-ASO/BO nanocomposite(with 60%ASO loading ratio)achieved a remarkable degradation efficiency,reducing pesticide(TAP)concentration from 100%to 28.0%within 100 min,while retaining 94.7%of its initial activity after four cycles(400 min).In stark contrast,the degradation efficiencies of the individual ASO and BO were substantially lower,with ASO achieving 56.6%and BO merely 58.8%.For DDVP,the composite also exhibited excellent photocatalytic degradation activity,reducing its concentration from 100%to 32.3%within 100 min,far outperforming ASO(100%to 67.8%)and BO(100%to 47.9%).Enhanced charge migration within the S-scheme heterojunction accounts for the remarkable catalytic efficiency.The charge transfer pathway and mechanism were further validated using femtosecond transient absorption spectroscopy(fs-TAS),adsorption energy calculations,differential charge density analysis,Kelvin probe force microscopy(KPFM),and in situ X-ray photoelectron spectroscopy(XPS).The results emphasize that S-scheme charge migration is vital for enhancing photocatalytic performance.Consequently,the ASO/BO heterojunction based on the S-scheme provides a robust and reliable route for achieving durable and efficient photocatalytic removal of environmental contaminants,with broad application prospects in agriculture,food safety,and the preservation of grain and meat products.