Heterogeneous Fenton reactants: a study of the behavior of iron oxide nanoparticles obtained by the polymeric precursor method

Nanoparticles composed of iron oxides and iron salts were obtained from polymeric resins produced by polymerizing Fe²⁺-citrate and Fe³⁺-citrate complexes with ethylene glycol. The citric acid:Fe molar ratio was varied to obtain different synthesis conditions. The materials were treated at 450 °C for 2 h to obtain nanoparticles, which were characterized by XRD, Mössbauer spectroscopy, FEG, CHNS, atomic absorption and surface area through N₂ physisorption. Rhodamine B photo degradation in the presence of these nanoparticles and hydrogen peroxide was carried out to analyze the possible behavior of nanoparticles as heterogeneous Fenton reactants. UV–visible spectroscopy revealed that the catalytic activity in the presence of nanoparticles obtained with a citric acid:Fe molar ratio of 12:1 was the condition that provided the best results in this work.