Enhanced photocatalysis using side-glowing optical fibers coated with Fe-doped TiO2 nanocomposite thin films

Abstract

Abstract This study characterized and evaluated photocatalytic efficiency of Fe-doped TiO 2 (Fe–TiO 2 ) nanocomposite thin films coated on side-glowing optical fibers (SOFs) for organic contaminant degradation. For the first time Fe–TiO 2 thin films with mixed anatase and rutile phases were successfully grown on SOFs using polymer assisted hydrothermal deposition (PAHD) method. The photocatalyst films were characterized using transmission and scanning electron microscopes, energy-dispersive X-ray, X-ray diffraction, and X-ray photoelectron spectroscopes. The photocatalytic efficiencies of the catalysts coated SOFs were studied by the degradation of Rhodamine B as a representative organic contaminant. The results showed that 5% Fe–TiO 2 thin films (Fe:TiO 2 molar ratio), mixture of anatase and rutile phases, achieved the highest photocatalytic activity under the irradiation of ultraviolet (UV) and visible light. The coupled adsorption and photocatalytic oxidation of Rhodamine B by the SOFs coated with photocatalyst nanocomposite thin films followed the Langmuir–Hinshelwood kinetic model, and the apparent first-order rate constants achieved 0.50 h −1 and 0.33 h −1 under UV and visible light irradiation, respectively. Photocatalytic degradation efficiency was affected by pH and initial organic concentration. Reactivation and regeneration of the used catalysts, and long-term photoactivity testing of catalysts coated SOFs demonstrated the durability of synthesized photocatalysts for water treatment.