Facile Solid-State Synthesis Of Heterojunction Ceo2/Tio2 Nanocomposite As An Efficient Photocatalyst For The Degradation Of Organic Pollutants

In this study, CeO2/TiO2 nanocomposites (NCs) were synthesized by adopting a straightforward two steps method comprising, first, the synthesis of CeO2 and TiO2 nanoparticles by wet chemical precipitation method and second, the heterostructure CeO2/TiO2 NCs by solid-state reaction process. The CeO2/TiO2 NCs were characterized by X-ray diffraction, N-2 adsorption-desorption isotherm analysis, field emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, and UV-vis diffuse reflectance spectroscopy. Regardless of CeO2 content, the bandgap energies of CeO2/TiO2 NCs were lower than that of pure TiO2. Photocatalytic activity of the synthesized photocatalysts was assessed by degrading a model dye methylene blue under the illumination of UV light. The CeO2/TiO2 NCs containing 2 wt% CeO2 exhibited higher photocatalytic degradation efficiency compared to reference TiO2 (P25), pure TiO2, and CeO2/TiO2 NCs containing CeO2 other than 2 wt%. The alkaline environment was favorable for photocatalytic decomposition of cationic dye methylene blue (MB). The enhanced degradation efficiency of CeO2/TiO2 NCs was substantiated in terms of vectorial charge separation and the reduction of photogenerated charge carriers owing to the band offsets existing at the interface between CeO2 and TiO2 NPs. Finally, no significant change in the degradation efficiency of CeO2/TiO2 NCs after successive uses evidenced the stability and reusability of the photocatalysts. Therefore, it can be concluded that the synthesized CeO2/TiO2 heterostructure photocatalyst would be a promising candidate for application in wastewater treatment.