Effect of Fe3+ doping on the performance of TiO2 mechanocoated alumina bead photocatalysts

Abstract

Ferric ion was introduced to the commercial photocatalyst P25 (Degussa) by ultrasonic wet impregnation technique. The concentration of the dopant was varied from 0.0 to 3.0% Fe/Ti ratio. The doped TiO 2 was then loaded to alumina balls using mechanical coating technique and followed by calcination in air at 400, 450, 500 and 550 o C. The fabricated photocatalyst was characterized by X-ray diffraction, N 2 adsorption-desorption isotherms, scanning electron microscopy, UV-Vis diffuse reflectance spectroscopy, X-ray adsorption near edge structure and photoluminescence spectroscopy. The photocatalytic activity was tested by following the degradation of methylene blue (MB). It was found that the Fe 3+ doped TiO 2 /Al 2 O 3 has a combination of anatase and rutile phase and free of iron oxide phases. The optimum calcination temperature is 400 o C with 0.1% Fe 3+ concentration. The catalyst addresses the entrainment in photocatalytic reactors, eliminating the need for a post filtration process.

Synthesis, Structural Characterization and Photocatalytic Activity of Iron-Doped Titanium Dioxide Nanopowders

“…TiO 2 catalysts with iron doping showed a slightly higher photocatalytic activity for the discoloration of PNDA in the experiments performed with UV radiation. In agreement with previous reports [2,23] When visible radiation was used, the PNDA photocatalytic discoloration efficiency of iron doped TiO 2 was significantly higher than those observed for undoped TiO 2 . The improvement of the photoactivity could be explained by the smaller crystallite sizes of the catalysts but mainly by the large red-shift in the light absorption edge of TiO 2 towards the visible region of the electromagnetic spectrum, resulting from the presence of the iron ions into the lattice that increase their photoabsorptive properties.…”

Elucidation of Reaction Behaviors in Sonocatalytic Decolorization of Amaranth Dye in Water Using Zeolite Y Co-Incorporated with Fe and TiO<sub>2</sub>

“…In this case, as the wt% Fe was further increased, the e − -h + recombination rate would increase also due to the existence of excess amount of Fe which would act as a charge carrier to cause this reduction in the catalytic activity. Bajamundi et al [21] investigated the effect of Fe loading from 0 -3.0 wt% Fe on the activ-ity of TiO 2 /Al 2 O 3 and the higher degradation efficiency of methylene blue was at 0.1% Fe. As a conclusion it seems that increasing the concentration of Fe up to 0.4 wt% showed significant enhance in catalytic activity and the addition of higher concentration affected negatively on catalytic activity.…”

Manganese Loaded on Titania Surface by Impregnation Method for Photocatalytic Degradation of Reactive Red-3 Dye

“…However, the application of TiO 2 is limited to certain areas due to its rather high band gap energy (3.2 eV) that TiO 2 needs to be activated under UV irradiation for photocatalytic reaction process. Several researchers have already attempted to lower the band gap energy of TiO 2 and decreased the electron-hole recombination rate, which mainly includes doping with the transition metal ions such as Mn 2+ , V 3+ , and Fe 3+ [1][2][3][4][5][6][7][8]. The low amount of transition metals loaded on surface of TiO 2 was proposed to trap the charge carrier and make longer the lifetime of one or both of the charge carriers improving the efficiency of the photocatalyst [9].…”