Synergistic effect of FeO and CeO co-modified titanate nanosheet heterojunction on enhanced photocatalytic degradation.

CeO and FeO co-modified titanate nanosheet (FeO/CeO@TNS) was prepared by one-pot hydrothermal method; the photocatalyst exhibited large surface area with CeO and FeO particles well dispersed on the surface. The results of XRD, BET, and Raman proved that the CeO and FeO introduced in the TNS influenced its structure evolution from 3D to 2D. The modification resulted in a shift of the absorption edge toward a longer wavelength and the band gap reduced to 2.87 eV. The three-component systems performed excellent photocatalytic activity and cycle stability on phenol and methyl blue (MB) solution under sunlight; nearly total phenol and MB were degraded in dozens of minutes. And the reaction rate constant ( K) of FeO/CeO@TNS on phenol degradation was 1.77, 3.25, 4.88, and 13-fold of FeO@TNS, CeO@TNS, bare TNS, and P25, respectively. The enhanced photocatalytic activity could be ascribed to the efficient separation of photogenerated pairs through the formation of tandem n-n-n heterojunction among the three-component systems. This work will be useful for the design of other tandem n-n-n heterojunction photocatalytic systems for application in energy conversion and environmental remediation. [ABSTRACT FROM AUTHOR]