An eco‐responsible approach to the synthesis of <scp> AgFeO ₂ </scp> nanocomposite via <i>Portulaca oleracea</i> : Towards improved chlorpyrifos photocatalysis and antibacterial properties

Abstract This study reports the eco‐friendly synthesis of AgFeO 2 nanocomposite (NC) using Portulaca oleracea L. leaf extract as a natural reducing and stabilizing agent. The NCs, characterized by UV–Vis spectroscopy, FTIR, XRD, and SEM, exhibited a rhombohedral crystal structure (JCPDS Card No. 01‐075‐2147) with high phase purity, a crystallite size of 24.46 ± 3.74 nm, and spherical to quasi‐spherical particles (30–100 nm, mean 55–60 nm). Optical analysis revealed a direct bandgap of 1.53 eV and strong absorption at 440 nm, underscoring their photocatalytic potential. The NCs achieved 99.5% degradation of chlorpyrifos (80) within 90 min under solar irradiation, following pseudo‐first‐order kinetics (k = 0.051 min −1 ) driven by reactive oxygen species. Antibacterial assays demonstrated dose‐dependent inhibition against Staphylococcus aureus , Pseudomonas aeruginosa , Bacillus subtilis , Klebsiella pneumoniae , and Escherichia coli , with inhibition zones of 8.5 ± 0.70 mm to 18.5 ± 0.70 mm at 250–1000 μg·mL −1 , rivaling ciprofloxacin. FTIR confirmed the removal of organic residues post‐calcination, ensuring structural integrity. These findings position the AgFeO 2 NC as a versatile, sustainable platform for photocatalytic pollutant degradation and microbial control in environmental and biomedical applications.