A Low-nanosized Broad Spectrum Photocatalyst for Treatment of Pharmaceutical and Industrial Pollutants: New Ce_0.97Fe_0.03Zn_0.04O₂ Composition

Nanostructured Fe/Zn codoped CeO₂ photocatalyst revealed high visible light mineralization efficiencies for removal of pharmaceutical ciprofloxacin and industrial reactive yellow 145 dye. Nanocrystalline pure and Fe/Zn codoped CeO₂ (Ce_0.93Fe_0.03Zn_0.04O₂) powders have been synthesized by a simple coprecipitation manner. The X-ray crystal structure analysis proved the formation of face-centered cubic CeO₂ phase with low nano-crystallite sizes (7–9 nm). The transmission electron microscope (TEM) images of the two samples illustrated that the powders are composed of very small nano-sized particles have approximately spherical view. All particles of both powders have nearly homogenous size and shape. The Kubelka–Munk plot demonstrated that the energy band gap of the synthesized CeO₂ nanopowder was 3.18 eV. The modification of CeO₂ nanopowder by Fe/Zn ions improved the visible light absorption and also reduced its band gap energy to 2.52 eV. Environmentally, 98% and 96% removal efficiencies for reactive yellow 145 dye and medical ciprofloxacin antibiotic were realized by Fe/Zn codoped CeO₂ nanocatalyst. The perfect mineralization, good reusability and high elimination of different concentrations (10–30 ppm) encourages the use of this nanocatalyst for wastewater treatment. The radical trapping tests verified that the superoxide and hydroxyl radicals are the energetic species during the photodegradation reaction of pharmaceutical ciprofloxacin and industrial reactive yellow 145 dye.