Visible-Light Induced Simultaneous Oxidation of Methyl Orange and Reduction of Cr(VI) with Fe(III)-Grafted K₂Ti₆O₁₃ Photocatalyst

The broad absorption of visible light and efficient separation of photogenerated electron-hole pair with high redox ability are important for enhancing the photocatalytic process. Herein, visible light sensitive Fe(III)-grafted K₂Ti₆O₁₃ NBs were successfully synthesized by molten salt cum-impregnation method. Different analytical techniques such as XRD, UV-Vis-DRS, SEM-EDS, TEM, EPR and BET analyses were employed to characterize the structure, morphology, and surface elemental composition of the prepared samples. The surface grafting of amorphous form of Fe(III) nanocluster was confirmed by TEM and EPR analyses. The visible-light-driven photocatalytic removal of individual and binary mixture of Methyl orange and Cr(VI) was tested with prepared samples and the results indicated that simultaneous removal is more efficient in the presence of Fe(III)-grafted K₂Ti₆O₁₃. Particularly, 0.1 Fe(III)-K₂Ti₆O₁₃ has shown the best activity when compared with pure K₂Ti₆O₁₃ and Degussa P25. Efficient absorption of visible light and effective separation of charge carriers are the key factors for enhanced photocatalytic activity.