Biogenic synthesis of ferric oxide nanoparticles using the leaf extract of Peltophorum pterocarpum and their catalytic dye degradation potential

Plant-mediated green synthesis of nanoparticles is an eco-friendly and cheap method since it makes use of phyto-compounds present in various plant parts as reducing and stabilizing agents. Herein, magnetic, ferric oxide nanoparticles (FONPs) were prepared by utilizing the leaf extract of Peltophorum pterocarpum for the first time. Rod-like FONPs with agglomerations were witnessed in FE-SEM images. Sharp peaks for elemental oxygen and iron were witnessed in EDS spectrum. XRD spectrum ascertained the crystallinity of the FONPs and showed both γ and α–Fe₂O₃ phases. The average crystallite size was 16.99 nm. A large specific surface area (66.44 m²/g) was found in BET analysis and the FONPs were mesoporous (pore diameter = 7.92 nm). TGA results showed a 20% weight loss during heating up to 800 °C. FTIR spectrum showed significant bands for various phyto-compounds and Fe–O. The Fenton-like catalytic efficiency of FONPs was studied for the methylene blue dye degradation during which 90% removal was noticed within 220min. The experimental results were satisfactorily fitted into a second-order model with a degradation constant of 0.0987 L/mg min. Also, the catalytic activity of the FONPs was assessed for the removal of MB dye with the reducing agent NaBH₄. A remarkable dye degradation (92%) was attained within 27min, and the results were best suited for a first-order model with a kinetic degradation constant of 0.0856min⁻¹. Therefore, the green-synthesized FONPs obtained here could be used in the degradation of dyes as nanocatalysts for the remediation of wastewater.