Enhanced photocatalytic degradation of reactive dyes over FeTi[O.sub.3]/Ti[O.sub.2] heterojunction in the presence of [H.sub.2[O.sub.2]

In this work, photocatalytic degradation of two reactive dyes, Reactive Yellow 84 (RY 84) and Reactive Black 5(RB 5),on FeTi[O.sub.3]/Ti[O.sub.2] heterojunction in the presence of UV-visible radiation and [H.sub.2][O.sub.2] has been reported. FeTi[O.sub.3]/Ti[O.sub.2] heterojunction has been prepared from ilmenite FeTi[O.sub.3] and anatase Ti[O.sub.2] by employing oxalic acid as an organic linker. FeTi[O.sub.3]/Ti[O.sub.2] ratios have been varied from 1 to 5 wt.%, and the materials were characterized by X-ray diffraction, scanning electron microscope and diffused reflectance UV-visible spectroscopic analysis. The photocatalytic activity of FeTi[O.sub.3]/Ti[O.sub.2] heterojunction for the degradation of the organic dyes RY 84 and RB 5 in the presence of UV-visible light was found to be higher than that of pure Ti[O.sub.2]. The addition of [H.sub.2][O.sub.2] increases the rate of degradation of both dyes on FeTi[O.sub.3]/Ti[O.sub.2] heterojunction. It facilitates the fast degradation of dye solutions even when their concentration was above 100 mg/l, which is otherwise very slow due to the low transmittance of light by the dye solution. The extent of mineralisation of the reactive dye during photocatalytic degradation was estimated from chemical oxygen demand analysis. FeTi[O.sub.3]/Ti[O.sub.2] heterojunction photocatalyst was also found to have good photostability; the material retains almost 97 % of its initial activity even in the fifth cycle. Keywords Heterojunction * Photocatalyst * Reusability * Reactive dyes * UV-visible light