Transformation of CeO₂ into a mixed phase CeO₂/Ce₂O₃ nanohybrid by liquid phase pulsed laser ablation for enhanced photocatalytic activity through Z-scheme pattern

Cerium-based nanohybrids have attracted considerable attention in photocatalytic research owing to their remarkable potential in the photodegradation of environmental pollutants. However, the process of nanohybrid formation suffers from complex operations with specialized equipment, extreme conditions, long durations, and low yields, making it infeasible for efficient utilization. Considering the above obstacles, we herein describe the first pulsed laser ablation (PLA) for the synthesis of oxygen vacancy affluent CeO₂/Ce₂O₃ nanohybrids, as an alternative to hydrothermal and calcination methods. The microstructures and optical properties of the nanocomposites are characterized by TEM, XRD, XPS, and DRS analysis. The photocatalytic activity of the CeO₂/Ce₂O₃ nanohybrid showed an MB dye degradation rate superior to that of bare CeO₂ nanostructures. The enhanced performance of CeO₂/Ce₂O₃ was attributed to an oxygen-vacancy-driven Z-scheme mechanism, where efficient separation of the photogenerated charge carriers significantly contributed to photocatalytic enhancement. This was further evidenced by both PL and scavenger experiment results. Moreover, the synthesized CeO₂/Ce₂O₃ nanocomposites exhibit a strong blue emission, which could have potential applications in LED manufacturing.