Development of hierarchical magnesium oxide anchored cerium oxide nanocomposites with improved magnetic properties and photocatalytic performance

Europium-doped cerium oxide nanoparticles: investigating oxygen vacancies and their role in enhanced photocatalytic and magnetic properties

In this study, pure and europium-doped (2%, 4%, 6%, and 8%) cerium oxide (CeO2) nanoparticles (NPs) were employed for efficient dye removal through photocatalytic approach. XRD and TEM confirmed the formation of pure CeO2 nanoparticles, while XPS and Raman spectroscopy were used to analyze the electronic properties and lattice defects, such as oxygen vacancies. The presence of lattice defects, which increased with the concentration of Eu, was found to be responsible for the enhanced degradation of Rose Bengal dye (82.4% for 8% Eu-doped sample) in 75 min. FTIR confirmed the chemical composition of the synthesized sample. The band at 617 cm-1, corresponding to the symmetrical stretching vibration mode of (Ce-O-Ce) or (Ce-O-Eu). The magnetic properties of synthesized samples were examined using VSM, revealing an increase from 4.48 to 11.0 emu/g in magnetization. This enhancement was attributed to F-center exchange mechanism (FCE), resulting from the presence of oxygen vacancies. These findings contribute to the development of advanced materials for sustainable wastewater treatment and spintronics.

Enhanced photocatalytic degradation of organic dye by CeO2/CNT/GO hybrid nanocomposites under UV light for wastewater treatment

Development of nanocomposites as efficient photocatalysts for the removal of hazardous organic pollutants is always in dire demand due to increase in water pollution. In this article, a facile sol-gel method has been used to synthesize cerium oxide (CeO2) nanoparticles followed by their decoration over multi-walled carbon nanotubes (CNTs) and graphene oxide (GO) to construct binary as well ternary hybrid nanocomposites using ultrasonic treatment. The oxygen vacancy defects have been depicted using X-ray photoelectron spectroscopy (XPS) that may result into improved photocatalytic efficiency. The ternary hybrid nanocomposites (CeO2/CNT/GO) showed excellent photocatalytic efficiency towards degradation of rose bengal (RB) dye up to 96.9% in 50 min. CNTs and GO provide the interfacial charge transfer which inhibits the electron-hole pair recombination. The results obtained here indicate that these composites can be effectively utilized as promising materials for the degradation of harmful organic pollutants for wastewater treatment.

A Review on Photocatalysis Used For Wastewater Treatment: Dye Degradation

Water pollution is a global issue as a consequence of rapid industrialization and urbanization. Organic compounds which are generated from various industries produce problematic pollutants in water. Recently, metal oxide (TiO2, SnO2, CeO2, ZrO2, WO3, and ZnO)-based semiconductors have been explored as excellent photocatalysts in order to degrade organic pollutants in wastewater. However, their photocatalytic performance is limited due to their high band gap (UV range) and recombination time of photogenerated electron-hole pairs. Strategies for improving the performance of these metal oxides in the fields of photocatalysis are discussed. To improve their photocatalytic activity, researchers have investigated the concept of doping, formation of nanocomposites and core-shell nanostructures of metal oxides. Rare-earth doped metal oxides have the advantage of interacting with functional groups quickly because of the 4f empty orbitals. More precisely, in this review, in-depth procedures for synthesizing rare earth doped metal oxides and nonocomposites, their efficiency towards organic pollutants degradation and sources have been discussed. The major goal of this review article is to propose high-performing, cost-effective combined tactics with prospective benefits for future industrial applications solutions.