Fabrication of Fe_3O_4/CuO@C composite from MOF-based materials as an efficient and magnetically separable photocatalyst for degradation of ciprofloxacin antibiotic

摘要

In this work, a novel ternary Fe3O4/CuO@C composite was fabricated using iron-doped copper 1,4-benzenedicarboxylate metal-organic frameworks as a self-sacrificing template. The morphological, structural, and optical properties of the prepared composite were determined by various techniques, and its photocatalytic behavior was investigated for degradation of ciprofloxacin under visible light irradiation. The Fe3O4/CuO@C material presented a porous structure with a rough surface of about 4-20 mu m, and was composed of the Fe(3)O4/CuO nanocomposite uniformly distributed on a carbon support. The band gap energy of the obtained composite was found to be 2.0 eV, which was nearly two times lower than that of Fe3O4@C and CuO@C. As a result, Fe3O4/CuO@C exhibited high photocatalytic activity, achieving a degradation efficiency of 98.5% after 120 min irradiation at the optimum conditions (a catalyst dosage of 0.5 g L-1, pH of 7, CIP concentration of 15 mg L-1). The mechanism of ciprofloxacin degradation by Fe3O4/CuO@C was elucidated with the main contribution of center dot O-2 and center dot OH reactive radicals. The new composite catalyst could easily be recovered from the treated solution using an external magnetic field due to its superparamagnetic nature. Fe3O4 /CuO@C also showed good reusability and stability. The overall results indicated that the synthesized composite has significant application potential for controlling the risk of antibiotics in wastewater. (C) 2020 Elsevier Ltd. All rights reserved.