title: Improving the Photocatalytic Activity of Modified Anatase TiO2with Different Concentrations of Aluminum under Visible Light: Mechanistic Survey.
abstract: Visible light-driven Al-doped TiO2with different aluminum contents (2, 5 and 10 mol%) were synthesized via a facile sol-gel method. Fourier transform infrared (FTIR), UV-visible diffuse reflectance, energy dispersive X-ray (EDX) spectroscopy as well as X-ray diffraction (XRD), X-ray fluorescence (XRF) and scanning electron microscopy (SEM) methods were used for the characterization of the obtained nanoparticles. The photocatalytic performance of the samples was evaluated by the degradation of rhodamine B (RhB) under visible light irradiation. The yield of the degradation RhB was estimated to be 71%, 89%, 65% and 56%, for the bare TiO2, 2%, 5% and 10% Al-doped TiO2, respectively. It was found that 2 mol% of Al-doped TiO2shows the best photocatalytic performance. In low concentration of dopant, separation of photogenerated electron-hole pairs promoted, and subsequently, the degradation efficiency increased. It was proposed that the degradation of RhB by 2 mol% Al-doped TiO2photocatalyst follows both N-deethylation and chromophore cleavage mechanisms, while the N-deethylation still predominated over cleavage of dye chromophore structure. The key role of hydroxyl radicals in RhB degradation was verified by the effects of scavengers. In addition, the photocatalyst can be reused for three runs without any significant loss of its catalytic activity.
authors.affiliation: Department of Chemistry, Iran University of Science and Technology, Tehran, Iran.
authors.forename: Shahrara
authors.initials: S
authors.lastname: Afshar
authors.affiliation: Department of Chemistry, Iran University of Science and Technology, Tehran, Iran.
authors.forename: Shabnam
authors.initials: S
authors.lastname: Pordel
authors.affiliation: Chemistry and Biochemistry Department, Texas Tech University, Lubbock, TX.
authors.forename: Babak
authors.initials: B
authors.lastname: Tahmouresilerd
authors.affiliation: Department of Chemistry, Iran University of Science and Technology, Tehran, Iran.
authors.forename: Alireza
authors.initials: A
authors.lastname: Azad