Enhanced photocatalytic performance of Hemin (chloro(protoporhyinato) iron(III)) anchored TiO2 photocatalyst for methyl orange degradation: A surface modification method

摘要

TiO2 was prepared by sol-gel method through the hydrolysis of TiCl4 and its surface derivatization was carried out with molecular catalyst like Hemin (chloro(protoporhyinato)iron(III)). Catalyst was characterized by various analytical techniques like UV-vis spectroscopy, FT-IR, FE-SEM and XRD. The anchoring of Hemin on titania surface is confirmed by FT-IR spectra through the linkage of OCOTi bond and also by TGA-DSC and elemental analysis. The photocatalytic activity of the surface modified catalyst is tested for the degradation of methyl orange (MO) as a model compound under UV light. The Hemin impregnated TiO2 (H-TiO2) in presence of H 2O2 shows an excellent photocatalytic activity compared to pristine TiO2, Hemin, H2O2, TiO 2/H2O2, and Hemin/H2O2 systems. The enhancement in the photocatalytic activity is attributed to the presence of iron (III) porphyrin ring on the TiO2 surface, which reduces the electron-hole recombination rate and also by acting as a mediator for continuous production of enriched concentration of hydroxyl radicals along with various other reactive free radicals. © 2013 Elsevier B.V. All rights reserved.