Iron oxide nanoparticles synthesis through a benign approach and its catalytic application

Synthesis of iron oxide nanoparticles was carried out through an environmental benign route using tannic acid as reducing and capping agent. The TEM image shows the details of the poly-dispersity in size of the iron oxide nanoparticle and average diameter of the particles range in between 30 and 50 nm. XRD result rule out that iron oxide nanoparticle is a mixed phase constituted by Fe⁺² and Fe⁺³ ions. The average size of the particle determined from XRD data is 45.6 nm which is agreeable with the finding obtained from TEM images. This particle of iron oxide is used for the degradation of p-cresol and it successfully degraded p-cresol. Catalytic property of the iron oxide nanoparticle was also investigation using methylene blue as role model dye. Degradation of methylene blue dye was studied in presence of NaBH₄ and the degradation reaction followed first order kinetics with rate constant value of 1.6 × 10⁻³ min⁻¹. The rate constant of the reaction in absence of iron oxide nanoparticles is 4 × 10⁻⁴ min⁻¹, this result confirmed the catalytic nature of as such prepared iron oxide nanoparticles.