Herbicides represent a significant class of hazardous organic pollutants contributing to widespread environmental contamination, particularly in aquatic ecosystems. Among them, bentazone (BTZ), a widely used herbicide in agriculture, poses notable risks due to its high water solubility, resistance to hydrolysis, and mobility in soil, which can lead to groundwater and surface water pollution. The World Health Organization classifies BTZ as moderately hazardous (Class II), with a maximum acceptable concentration of 30 g L⁻¹ in drinking water. Its toxicological profile includes acute and chronic effects on humans, as well as toxicity to fish, birds, and mammals. Given these concerns, effective degradation technologies are urgently needed. Advanced oxidation processes (AOPs), particularly heterogeneous photocatalysis, have emerged as promising solutions due to their ability to generate highly reactive hydroxyl radicals (•OH) capable of mineralizing organic pollutants into CO₂ and H₂O.

This study investigates the synergistic effect of gold-silver (Au@Ag) bimetallic nanoparticles deposited on palygorskite (PAL) in combination with titanium dioxide (TiO₂) for enhanced photodegradation of bentazone under UV light. The synthesis of Ag and Au@Ag nanoparticles was carried out using sodium borohydride reduction in the presence of karaya gum as a stabilizer.DCX Antibody Technical Information Characterization via UV-Vis spectroscopy confirmed the formation of core@shell bimetallic structures, with characteristic plasmonic absorption peaks at 396 nm (AgNPs) and 397 nm (Au@AgNPs). Dynamic Light Scattering (DLS) and zeta potential measurements revealed average hydrodynamic diameters of 52.12 nm (AgNPs) and 76.34 nm (Au@AgNPs), with surface charges below -30 mV, indicating good colloidal stability. X-ray diffraction (XRD) analysis showed no distinct crystalline peaks for Ag or Au, suggesting low metal loading and strong interaction with the clay matrix. Scanning electron microscopy (SEM) images clearly displayed small spherical nanoparticles uniformly distributed along the fibrous PAL structure, confirming successful deposition.

Photocatalytic experiments demonstrated that neither pure TiO₂, nor PAL alone, nor individual nanoparticle composites (Ag-PAL or Au@Ag-PAL) achieved satisfactory BTZ degradation.540737-29-9 MedChemExpress However, when combined with TiO₂, both composite systems exhibited significantly enhanced performance.PMID:34383277 The Au@Ag-PAL+TiO₂ system achieved the highest degradation efficiency—65% after 240 minutes—outperforming Ag-PAL+TiO₂ (54%) and bare TiO₂ (34%). This improvement is attributed to the synergistic interplay between the bimetallic nanoparticles and TiO₂: Au@Ag nanoparticles act as efficient electron sinks, reducing electron-hole recombination in TiO₂; meanwhile, localized surface plasmon resonance (LSPR) enhances visible and UV light absorption, promoting charge separation and radical generation. Additionally, the use of palygorskite as a porous support improves dispersion, prevents nanoparticle aggregation, and facilitates catalyst recovery.

The photocatalyst maintained over 92% efficiency even after three reuse cycles, demonstrating excellent stability. Post-cycling XRD and SEM analyses confirmed minimal structural changes and consistent morphology, supporting the durability of the composite. Importantly, toxicity assessments using *Artemia salina* showed no significant mortality (>80% survival) following exposure to post-degradation solutions, indicating that the photoproducts were non-toxic. These findings confirm that the Au@Ag-PAL+TiO₂ system not only effectively degrades bentazone but also produces environmentally safe byproducts.

In conclusion, this work highlights the potential of bimetallic nanoparticle-clay-semiconductor hybrids in sustainable water treatment. The synergy between Au@Ag nanoparticles, palygorskite, and TiO₂ creates a highly efficient, stable, and eco-friendly photocatalytic system ideal for the remediation of persistent herbicides like bentazone.MedChemExpress (MCE) offers a wide range of high-quality research chemicals and biochemicals (novel life-science reagents, reference compounds and natural compounds) for scientific use. We have professionally experienced and friendly staff to meet your needs. We are a competent and trustworthy partner for your research and scientific projects.Related websites: https://www.medchemexpress.com