Enhanced Visible-Light-Responsive Photocatalytic Degradation of Ciprofloxacin by the Cu(x)O/Metal-Organic Framework Hybrid Nanocomposite

Ciprofloxacin (CIP) is a commonly used antibiotic, however, once in the environment, it is highly toxic with a poor biodegradability. Given these attributes, an effective strategy for the removal of CIP is urgently needed for the protection of water resources. Herein, a novel copper metal-organic framework (Cu(x)O/MOF) multifunctional material has been produced, in this work, by the calcination of Cu-MOF urea at 300 °C, in the presence of a 5% H(2) atmosphere. The morphological, structural, and thermal properties of the prepared Cu(x)O/MOF were determined through various techniques, and its photocatalytic behavior was investigated for the degradation of CIP under visible-light irradiation. The prepared Cu(x)O/MOF bifunctional material is presented as a graphitic carbon-layered structure with a particle size of 9.2 ± 2.1 nm. The existence of CuO-Cu(2)O-C, which was found on the Cu(x)O/MOF surface, enhanced the adsorption efficiency and increased the photosensitivity of Cu(x)O/MOF, towards the degradation of CIP in aqueous solutions. The tailored Cu(x)O/MOF, not only shows an excellent CIP degradation efficiency of up to 92% with a constant kinetic rate (k(obs)) of 0.048 min(−1) under visible light, but it can also retain the stable photodegradation efficiency of >85%, for at least six cycles. In addition, Cu(x)O/MOF has an excellent adsorption capacity at pH 6.0 of the maximum Langmuir adsorption capacity of 34.5 mg g(−1) for CIP. The results obtained in this study demonstrate that Cu(x)O/MOF is a reliable integrated material and serves as an adsorbent and photocatalyst, which can open a new pathway for the preparation of visible-light-responsive photocatalysts, for the removal of antibiotics and other emerging pollutants.