CeO2-Bi2O3 nanocomposite: Two step synthesis, microstructure and photocatalytic activity

CeO₂-Bi₂O₃ composite was synthesized via a two-stage process. The precursors were prepared from Ce(NO₃)₃·6H₂O, Bi(NO₃)₃·5H₂O and CO(NH₂)₂ with different molar ratio through the hydrothermal process, and then was completed by carrying out the precursors for 4 h at 600 °C under flowing air atmosphere. Techniques of X-ray diffraction (XRD), transmission electron microscopic (TEM) and diffuse reflectance ultraviolet-vis spectra (UV-DRS) were employed to characterize the as-synthesized materials. The results showed that the microstructure and morphology of CeO₂-Bi₂O₃ composite were similar in spite of different inverse proportion. We also investigated improved photocatalytic activity in the case of CeO₂-Bi₂O₃ composite catalyst compared to the catalytic activity of pure Bi₂O₃ or CeO₂ powder. The suppression of charge recombination in the composite CeO₂-Bi₂O₃ catalyst led to higher catalytic activity for the degradation of RhB. The CeO₂ 10%/Bi₂O₃ photocatalyst exhibited maximum photocatalytic activity. The photocatalytic activity is in close relation with the inverse proportion between reactants.