Iron incorporated porous cerium oxide nanoparticles as an efficient photocatalyst for different hazardous elimination

Porous ceria (CeO2) nanoparticles and iron-doped porous ceria with different iron contents (1 wt%, 2.5 wt%, 5 wt% and 10 wt%) were prepared using a one-pot simple process. Several characterization techniques were applied to characterize the prepared materials, including inductively coupled plasma (ICP) elemental analysis, X-ray diffraction (XRD), Fourier transform infrared (FTIR), N2 sorption measurements, scanning electron microscopy (SEM), high resolution-transmission electron microscopy (HR-TEM), and DR-UV-Vis. The obtained results confirm the incorporation of iron ions in the CeO2 lattice, with no evidence for the formation of iron oxide as a separate phase. More importantly, the light absorption property of Fe-doped porous ceria samples is found to be red-shifted and the calculated bandgap decreases from 3.08 to 2.66 eV for pure porous ceria and 10 wt% Fe-doped ceria, respectively. Under the illumination of visible light, the photocatalytic activity of Fe-doped porous ceria was investigated through the decolourization reaction of methyl green aqueous solution as a model contaminant in industrial wastewater. The obtained photocatalytic data show a remarkable increase in activity by almost 4.8 times higher compared to a pure ceria sample. Furthermore, the prepared Fe-doped ceria sample exhibits good reusability up to the fourth consecutive reaction without treatment. Moreover, the best-performing sample was further investigated in two additional photocatalytic reactions; the first is the elimination of phenol in an aqueous solution, while the second is the degradation of a gas mixture containing four short-chain hydrocarbon gases. The results of both reactions confirm the great improvement in the photocatalytic performance of Fe-doped porous ceria compared to a pure porous ceria sample.