Zirconium-based mixed ligand metal–organic framework for efficient adsorption of organic dyes

Due to the rapid advancement in civilization and industrialization, there is an increase in the contamination of water due to dumping or accumulation of waste and harmful products in water resources. As a result, freshwater scarcity has become a major concern worldwide and needs to be addressed by finding ways to avoid, remove, or degrade these harmful contaminants in water. Metal–organic frameworks (MOFs) act as a potential and promising candidate for removing and degrading harmful organic dyes from wastewater. In this study, we successfully synthesized a new Zirconium-based MOF (Zr-MOF) by the solvothermal method using melamine and trimesic acid as organic moieties. The synthesized Zr-MOF particles are monodispersed in nature with an average hydrodynamic diameter of 200 nm as demonstrated by dynamic light scattering (DLS) measurements. Its formation and stability were confirmed by spectroscopic techniques including FTIR and XRD methods. The formed MOF displayed tremendous capability in degrading cationic as well as anionic dyes. It shows a surface area of 795.64 m²/g. The Zr-MOF shows adsorption percentages of 97.2% and 80.3% for Congo Red (CR) and Toluidine Blue (TB) respectively. Owing to a positively charged surface, the Zr-MOF showed more potential for adsorption of anionic dye because of electrostatic interactions. These MOFs showed 96.4% and 57.9% reusability in the second cycle for CR and TB, respectively, indicating their strong affinity towards anionic dye (CR). We have also reported the adsorption kinetics, stability, and reusability of Zr-MOF in the efficient removal of pollutants from water in this manuscript. Hence, with recent advancements and developments, this study may offer new inspirations for tuning and designing the membrane with superior dye removal which can be extended to laboratory and industrial usage.