Modulation of polymorphic structure of Ag/Ce–MOFs materials and its adsorption mechanism of Minocycline in water

Abstract

Minocycline (MNC), as a second-generation semi-synthetic derivative of tetracycline, poses a potential carcinogenic threat to organisms in water, therefore high efficient removal of MNC is becoming a crucial key for water quality safety. This study has been successfully synthesized Ag/Ce bimetallic–doped MOF materials with diverse morphological characteristics by using microwave digestion and solvothermal methods, and it was demonstrated a significant adsorption potential in MNC from aqueous solutions. The characterization results were revealed that Ce exhibits oxygen vacancy enrichment as the central metal in MOFs, while Ag was distributed on carbon framework in the form of Ag⁰ NPs, both of morphological features were provided more active sites for adsorption. The Ag/Ce–MOFs was achieved 98.26 % exceptional MNC adsorption efficiency at pH 9, which was followed a multilayer exothermic chemisorption mechanism. The results were shown that the maximum adsorption capacity of Ag/Ce-MOFs was 476.2 mg/g in Langmuir model, which was much more substantially surpassed than Ce–MOFs. In addition, the adsorption process was primarily mediated through hydrogen bonding, ligand interactions and amidation reactions. Furthermore, the Ag/Ce–MOFs exhibited the excellent regeneration performance and broad applicability, which was shown remarkable adsorption potential in removing various other pharmaceutical contaminants in water. In summarization, the synthesized Ag/Ce–MOFs by microwave digestion and solvothermal technology, were demonstrated the board promising prospects in efficient MNC removal in water treatment applications.