Tailoring Vanadium-Based Magnetic Catalyst by In Situ Encapsulation of Tungsten Disulfide and Applications in Abatement of Multiple Pollutants

Abstract

A magnetic nanocomposite of tungsten and vanadium was employed as a catalyst for the mitigation of water contaminants, including a carcinogenic dye (Congo red, CR), a widely used pesticide (glyphosate), and the bacterial strain Escherichia coli . Additionally, it was subjected to several characterization techniques. X-ray diffraction spectroscopy examination validated the synthesized nanoparticles’ crystalline nature, and scanning electron microscopy and energy-dispersive X-ray analysis were employed to examine the morphology and elemental composition of the catalyst. The use of thermogravimetric analysis enabled the elaboration of the thermal behavior of tungsten sulfide–vanadium decorated with Fe 2 O 3 nanoparticles. The experiments were conducted under visible light conditions. The highest levels of photodegradation of 96.24 ± 2.5% for CR and 98 ± 1.8% for glyphosate were observed following a 180 min exposure to visible light at pH values of 6 and 8, respectively. The quantum yields for CR and Gly were calculated to be 9.2 × 10 –3 and 4.9 × 10 –4 molecules photon –1 , respectively. The findings from the scavenger analysis suggest the involvement of hydroxyl radicals in the degradation mechanism. The study evaluated the inhibition of E. coli growth when exposed to a concentration of 0.1 g/10 mL of the photocatalyst, utilizing a 1 mL sample of the bacterial strain. The successful elimination of CR and glyphosate from water-based solutions, along with the subsequent antibacterial experiments, has substantiated the efficacy of the photocatalyst in the field of environmental remediation.