Enhanced activity of iron oxide dispersed on bentonite for the catalytic degradation of organic dye under visible light

Natural clay-supported iron oxide was prepared by deposition method, and dried at 120 °C. It was found that under visible light in the presence of H2O2, this catalyst was highly active for degradation of cationic (malachite and fuchsin basic) and anionic dyes (orange II and X3B) in water at pH 6.5, as compared with bare iron oxide or the clay-supported iron oxide sintered at 350 °C. The excellent performance of the catalyst is correlated with its high sorption capacity toward both types of dyes, thus resulting in enhanced dye degradation via a photosensitization pathway. The catalyst was characterized by XRD, nitrogen adsorption, infrared, and UV–visible spectroscopy.