Ceria Nanoparticles Decorated on Nanostructured Silica as Photocatalysts for the Remediation of Dye in Wastewater

We report the design and synthesis of ceria nanoparticles decorated on nanostructured bicontinuous concentric lamellar (bcl) silica as a photocatalyst for the remediation of dye in wastewater. The influence of the silica form (as-synthesized vs calcined bcl silica) and the addition of polyvinylpyrrolidone (PVP) were systematically investigated to optimize the ceria loading. Subsequently, the ceria content was varied to tailor the morphological, structural, and optical properties of the resulting composites. PVP acted as a stabilizing and coordinating agent, enhancing the interaction between cerium ions and the silica surface and enabling uniform ceria dispersion across the nanostructured lamellar architecture. Structural characterization confirmed successful ceria integration and the high purity of the catalyst, while spectroscopic analyses revealed improved light-harvesting capabilities. The photocatalytic degradation of Rhodamine B was monitored in situ via time-dependent photoluminescence spectroscopy, providing detailed insights into reaction kinetics. The results demonstrate that the synergy between the nanostructured bcl silica framework and ceria nanoparticles enhances photochemical activity relative to pristine ceria, underscoring the promise of this nanostructured hybrid for wastewater treatment applications.