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.