Ecofriendly magnetic nanocomposite (Fe₃O₄/SiO₂/Ag) fabrication for sustainable dye wastewater management: catalysis and SERS for a cleaner approach

Our study focuses on sustainable dye wastewater management through catalysis, scrutinized by surface-enhanced Raman spectroscopy (SERS) using an ecofriendly magnetic nanocomposite (Fe₃O₄/SiO₂/Ag (FSA)). To our knowledge, the use of green synthesis for fabricating nanocomposites from a single source, namely Nerium oleander leaves, has not been extensively explored. This poses a distinctive and challenging approach, differentiating it from conventional chemical methods. Analytical investigations confirm the nanocomposite morphology, featuring Fe₃O₄ cubic cores with SiO₂ spheres and silver nanoparticles (AgNPs) decoration. Efficient catalysis rapidly degrades unary and binary dye systems (MB, RhB, and MB + RhB), with high efficiency in short durations (MB: 96% in 10 min, RhB: 94% in 2 min, MB + RhB: 96% MB and 91% RhB in 9 min) and with elevated "k" values. SERS monitors water quality, revealing complete degradation and quenching of dye fingerprints with fabricated nanocomposite FSA. The nanocomposite exhibits reusability over four cycles by easy recovery of catalyst with external magnet. The nanocomposite achieved 89.7% degradation efficiency in real-time household wastewater treatment. The proposed research aligns with UN SDGs 6 and 15 and this approach holds promise for advancing industrial waste management.