In order to improve the visible light catalytic degradation efficiency of monomer BiOI

the three-dimensional floral structure of CeO2 was prepared by calcination at different temperatures. Then

CeO2 was added to BiOI precursor solution and BiOI/ CeO2 composite photocatalysts with different composite ratios were prepared by solvothermal method. X-ray powder diffraction ( XRD)

scanning electron microscope ( SEM)

ultraviolet-visible diffuse reflectance spectroscopy ( UV-Vis DRS) and electrochemistry were used to characterize the prepared samples

and the effects of CeO2 calcination temperatures and different mass ratios on the photocatalytic degradation efficiency were evaluated by the degradation experiments of rhodamine B ( RhB) .The photocatalytic mechanism of the composites was analyzed by radical trapping experiments. The results showed that when the mass ratio of BiOI to CeO2 (400℃ ) was 1∶ 1

the degradation rate of RhB was the best

which was about 38. 1%. Compared with BiOI ( about 24% ) and CeO2 ( about 23% )

the degradation rate was improved. This may be attributed to the heterojunction structure formed at the interface after the composite of the two materials

which effectively inhibits the photoelectron-hole recombination rate and improves the photocatalytic performance.