Contribution à l’etude structurale et physico-chimique des oxydes mixtes type pérovskite et ruddlesden-popper sur les applications photo-catalytiques

Abstract

This thesis addresses the issue of water pollution caused by dyes, focusing on methylene blue, a common but challenging pollutant to remove. A simple, low-cost sol-gel process using citrate was developed to produce mixed perovskite (AFeO3, with A = La, Sr) and Ruddlesden-Popper (Sr2FeO4, Sr2-xMxFeO4 with M = Ni, Ce, La and x = 0.2). These materials were evaluated as for the of methylene blue under visible light, following calcination at 650°C, 850°C, and °C. The powder structure was identified using X-ray diffraction (XRD), revealing that the resulting materials exhibit a Ruddlesden-Popper phase. Molecular structures and vibrational bands were analyzed using -transform infrared spectroscopy (FTIR), and the band gap energy of the compounds was found to be 2.7 ± 0.2 eV. Powder morphology was using scanning electron (SEM). The effect of various on the efficiency of methylene blue removal was . The photocatalytic kinetics followed a pseudo-second-order model. These results highlight the of iron-based , which are cost-effective and readily accessible, for the degradation of water pollutants under natural light.