Novel photocatalyst for fast treatment of ciprofloxacin and crystal violet pollutants: In³⁺-doped CuO/CuMn₂O₄ nanocomposite

Removal of organic pollutants by adsorption/visible light photocatalysis is a promising strategy for wastewater treatment. Pure and In-doped CuO/CuMn₂O₄ nanocomposites were prepared via a simple sol–gel method. The X-ray diffraction (XRD) analysis proved the formation of nanocrystalline CuO/CuMn₂O₄ nanocomposites without any impurities. The addition of In³⁺ ions to CuO/CuMn₂O₄ leads to formation of fine grains. Besides, the doping by In³⁺ ions enhances the harvesting of visible light energy of CuO/CuMn₂O₄ nanocomposite. In-doped CuO/CuMn₂O₄ sample exhibited a huge dielectric permittivity with estimated value of 43,306 at the lowest frequency. For environmental applications, In-doped CuO/CuMn₂O₄ catalyst revealed fast photodegradation efficiencies of 97 and 95% for crystal violet and ciprofloxacin contaminants after 25 min of solar irradiation, respectively. The total organic carbon (TOC) and chemical oxygen demand (COD) analyses confirmed the perfect mineralization of crystal violet and ciprofloxacin compounds to carbon dioxide (CO₂) and water (H₂O) molecules. The measured results demonstrated that the In-doped CuO/CuMn₂O₄ nanocomposite has multifunctional properties for electrical storage devices and treatment of organic wastewater.