Engineered SnO 2/BiOI fibers via electrospinning for robust visible-light/peroxymonosulfate -driven multipollutant mineralization
Engineered photocatalysts capable of operating under visible light and realistic water matrices are needed to address emerging pharmaceutical contaminants. Here, we fabricate SnO<sub>2</sub>/BiOI fibrous heterostructures by electrospinning SnO<sub>2</...
| Autores: | , , , , , , |
|---|---|
| Formato: | artículo |
| Estado: | Versión publicada |
| Fecha de publicación: | 2026 |
| País: | España |
| Recursos: | Universidad de Barcelona |
| Repositorio: | Dipòsit Digital de la UB |
| OAI Identifier: | oai:dnet:ubarcelona__::95d93dbbd8be7fadb49980e5644c240d |
| Acesso em linha: | https://hdl.handle.net/2445/229484 |
| Access Level: | acceso abierto |
| Palavra-chave: | Fotoelectroquímica Fotocatàlisi Absorció de la llum Photoelectrochemistry Photocatalysis Light absorption |
| Resumo: | Engineered photocatalysts capable of operating under visible light and realistic water matrices are needed to address emerging pharmaceutical contaminants. Here, we fabricate SnO<sub>2</sub>/BiOI fibrous heterostructures by electrospinning SnO<sub>2</sub> nanofibers decorated with solvothermally synthesized BiOI followed by calcination. The electrospun fibers provide a mechanically robust, high-surface-area scaffold, while BiOI incorporation enhances visible-light absorption and creates SnO<sub>2</sub>/BiOI heterointerfaces. Textural, optical, and spectroscopic analyses reveal progressive surface decoration, increased surface area, and defect-rich Bi environments as BiOI loading increases. Using tetracycline (TC) as a model contaminant at neutral pH, SnO<sub>2</sub>/BiOI composites markedly outperform pristine SnO<sub>2</sub> under visible light and/or peroxymonosulfate (PMS), with an optimal BiOI content (SBO2) under single-stimulus conditions and near-complete TC mineralization for the highest loading (SBO3) in the PMS + visible-light system. Radical scavenging indicates that SO<sub>4</sub><sup>•−</sup> and <sup>•</sup>OH are the dominant reactive species, with O<sub>2</sub><sup>•−</sup>, h<sup>+</sup> and e<sup>−</sup> playing secondary roles. A multipollutant mixture (TC, sulfamethoxazole, levofloxacin, lansoprazole) is mineralized by >80% in both Milli-Q and tap water, and SBO3 retains high activity over nine cycles with Bi and I leaching below 0.05% after 48 h. Density functional theory calculations, combined with XPS, support an S-scheme SnO<sub>2</sub>/BiOI heterojunction, enabling spatial separation of strongly reducing electrons in BiOI and oxidizing holes in SnO<sub>2</sub>. Although high PMS loadings can partially mask intrinsic catalyst differences, these results outline a practical design platform for heterogeneous (slurry), visible-responsive, PMS-assisted photocatalysts for pharmaceutical-laden effluents. |
|---|