Promoting the photocatalytic removal rate of ciprofloxacin antibiotic over carbon fiber decorated tungsten trioxide/titanium dioxide catalysts

Abstract

This work aimed to enhance the photocatalytic degradation efficiency of WO₃/TiO₂ catalyst by decorating with carbon fibers (CF) which have excellent conductivity and uniform micropore size distribution. The carbon fiber based catalysts were prepared through a facile solvothermal technique and the as-synthesized samples were characterized by X-ray photoelectron spectroscopy (XPS), Scanning electron microscopy (SEM) and UV–Vis diffuse reflectance spectroscopy (UV-DRS), Raman and X-ray powder diffraction (XRD) techniques. The photocatalytic activities of carbocatalysts were investigated by degrading the selected antibiotic (ciprofloxacin) under day light illumination. When the amount of carbon fiber was increased from 2.5 wt.% to 9 wt.%, the photocatalytic degradation rate was almost doubled. The effects of different parameters such as carbon fiber amount, solution pH and water matrix on the catalytic performance were explored; and the effect of radical ions was investigated by adding trapping agents. The promoted activity for the carbocatalysts was assigned to the synergetic effect of adsorption/photocatalysis, electrical features of carbon fibers and reduced band gap energy.

Keywords:

• Carbon fiber
• ciprofloxacin
• pharmaceutical
• photocatalysis
• TiO₂
• WO₃