Boosting the photocatalytic performance of Bi2Fe4O9 through formation of Z-scheme heterostructure with In2S3: Applications towards water decontamination. (November 2022) - Das, Krishnendu
Abstract: Design of biocompatible nano-heterostructure photocatalyst with broad UV–visible spectrum response and strong redox ability is a promising approach with potential application in micropollutant degradation and pathogen deactivation from aqueous sources. Herein, we have reported the facile fabrication of In2 S3 /Bi2 Fe4 O9 (ISxBFO) binary heterostructure by hydrothermally depositing In2 S3 nanoparticles (20–40 nm) over Bi2 Fe4 O9 nanocuboids/nanoplates prepared by combustion synthesis route. In depth characterization study revealed broad spectrum UV–Vis absorption, large interfacial contact, improved charge carrier separation and mobility and a longer excited state life time (4.7 ns) for the ISxBFO heterostructure materials. The integration of In2 S3 with Bi2 Fe4 O9 strongly boosts the optoelectrical and photocatalytic property of pristine Bi2 Fe4 O9 . The ISxBFO heterostructure material exhibited enhanced photocatalytic efficiency for aqueous phase degradation of sulfamethoxazole antibiotics (kapp = 0.06 min −1 ) and phenyl urea herbicides (kapp = 0.028 min −1 ) with reaction rates 3–8 times higher than the pure BFO component. The MTT assay experiments confirmed non-cytotoxic nature of treated sulfamethoxazole and diuron solutions. The composite materials also displayed convincing antibacterial behavior towards toxigenic Vibrio cholerae pathogen. Haemagglutination assay study revealed excellent biocompatibility of the binary composite up to 200 mg L −1 . Radical trapping study suggested expeditious generation of OH and O2 − radicals over the ISxBFO surface which is nearly 3.8 and 2.3 times higher than pure BFO and In2 S3 respectively. The occurrence of a direct Z-scheme mechanism is inferred from radical trapping and XPS study which accounted for the improved photocatalytic activity and strong radical generation property of the ISxBFO heterostructure material. Graphical abstract: Image 1 Highlights: A broad spectrum visible light active Z-scheme In2 S3 /Bi2 Fe4 O9 composite fabricated. Composite exhibited better photoelectrochemical feature and excited state life time. Enhanced activity for sulfamethoxazole and phenyl urea herbicide photodegradation. Convincing photocatalytic antibacterial property for toxigenic Vibrio cholera. Haemagglutination assay study revealed biocompatible nature of the composite.