Synergistic effects of sulfation and Fe-doping on the photocatalysis of titania

Abstract

Fe-doped sulfated titania photocatalysts were prepared by one-step thermal hydrolysis of industrial titanyl sulfate and characterized using XRD, FT-IR, UV-Vis DRS, and N 2 adsorption-desorption techniques. The effects of the volume ratio of pre-adding water to TiOSO 4 on the structure of the titania photocatalysts were investigated. The photocatalytic activities of Fe-doped sulfated titania samples were evaluated using the photooxidation of methylene blue in aqueous solutions under UV light irradiation. The results indicate that Fe-doping induces the red shift of the absorption edge to the visible light range. Meanwhile, sulfur species in the form of sulfate are incorporated into the network of Ti-O-Ti and coordinated to titania in bidentate models, which can effectively promote the separation of the photogenerated electrons and holes. Synergistic effects of both are beneficial for improving the photocatalytic activity of the Fe-doped sulfated titania photocatalysts.Photocatalysis has received considerable attention over the past two decades because of its promising applications such as in renewable energies and environmental protections [1, 2]. As an important semiconductor photocatalytic material, titania has attracted a great deal of research interest due to its good chemical stability, insolubility in water, non-toxicity and cost-effectiveness. However, the relatively high intrinsic band gap of titania (3.2 eV for the anatase) restricts its utilization of solar energy. On the other hand, the photogenerated electrons and holes can easily recombine, which induces the low quantum efficiency. Studies indicate that iron-doping can effectively extend the spectral

Photocatalytic degradation of methylene blue and phenol on Fe-doped sulfated titania

“…The more detailed procedure can be found in references [11,12]. In a typical synthesis, 150 mL TiOSO 4 solution and 34.5 mL pre-adding water were preheated to 96 ± 1°C, respectively.…”

“…The UV light source is a commercial 8-W black-light tube with a spectral peak at around 365 nm. The photocatalytic reactor used for UV light irradiation can be found in references [11,12].…”

“…Industrial titanyl sulfate solution containing abundant iron and sulfate, a low-cost industrial intermediate product in the titanium dioxide pigment production process, has been used as a raw material, and FST photocatalysts were successfully prepared by the simple one-step thermal hydrolysis method in the previous works of our group [11,12]. In addition, the effects of the volume ratio of pre-adding water to TiOSO 4 and the m(Fe)/m(TiO 2 ) on the structures and the photocatalytic activity of FST photocatalysts have also been studied.…”

Thermodynamic studies of methylene blue adsorption onto Fe-doped sulfated titania

“…In the previous work of our group, using low-cost industrial titanyl sulfate solution as raw material, which contains abundant iron and sulfate, Fe-doped sulfated titania (denoted as FST) photocatalysts were prepared by the one-step thermal hydrolysis method, and the effects of the volume ratio of pre-adding water to TiOSO 4 and the m(Fe)/m(TiO 2 ) on the structures and the photocatalytic activity of FST photocatalysts have been studied [11,12]. The aim of this work is to investigate the adsorption equilibrium of methylene blue onto FST photocatalysts at three different temperatures (298, 303 and 308 K).…”

Effects of Calcining Temperature on Photocatalytic Activity of Fe‐Doped Sulfated Titania

“…The more detailed procedure can be found in Yang et al. (21,22). In a typical synthesis, 150 mL TiOSO 4 solution and 34.5 mL preadding water were preheated to 96 ± 1°C, respectively.…”