Efficient photocatalytic degradation of azo dyes using Achyranthes aspera-mediated magnetic iron oxide nanoparticles: A green synthesis approach

Abstract

Environmental pollution, particularly from industrial effluents, has become a warning to human well-being owing to its hazardous effects. The discharge of harmful organic dyes, chlorinated organic pollutants, and toxic heavy metals into water bodies demands efficient and sustainable remediation solutions. In this context, one promising solution is to explore biologically synthesized magnetic nanoparticles, which provide an eco-friendly, cost-economical, and ease of significant production alternative for wastewater treatment. In the current study, iron nanoparticles oxide (AaIONPs) with remarkable magnetic properties were successfully produced by exploring a bio-reduction technique, utilizing an aqueous leaf extract of Achyranthes aspera (Apamarg) serving as a natural reducing and capping agent. The phytosynthesized AaIONPs were characterized through X-ray diffraction spectroscopy (XRD), Fourier transform infrared spectroscopy (FTIR), Scanning electron microscopy (SEM), Zeta analysis, Energy dispersive X-ray spectroscopy and Nanoparticle Tracking Analysis (NTA) to observe various properties of nanoparticles. The average diameter varied from 5 nm and 60 nm. The photocatalytic dye degradation efficiency was assessed using UV Vis absorption spectroscopy. For five retrieval cycles, the magnetic AaIONPs showed 90 % and 95 % decolorization efficiency against Methylene Blue (MB) and Crystal Violet (CV). Altogether, these findings highlight that green synthesized AaIONPs using A. aspera leaf extract are not only effective in the degradation of toxic organic pollutants but also reusable, making these nanoparticles a sustainable candidate for wastewater treatment, which in turn controls environmental pollution.