Self-assembly of C@FeO nanopillars on 2D-MOF for simultaneous removal of microplastic and dissolved contaminants from water

Environmental pollution is a significant contributor to diseases in living organisms, with water being crucial to humans, plants, and aquatic’s survival. However, removing both solid and dissolved contamination in water remains a significant challenge. Small size solids are most concerning due to the difficulty in detecting and removing them using current technologies. Therefore, developing an innovative and cost-effective method becomes a high priority. Herein, we developed a novel approach to remove solids and dissolved contaminants simultaneously using nanopillared structures composed of two-dimensional (2D) metal-organic framework (MOF) separated by carbon encapsulated iron oxide ([email protected]) nanopillars. The nanopillared structure features a high surface area (749.7 m2/g), abundant active sites, and magnetic properties for separation of pollutants. 2D [email protected]@FeO removed ∼100 % micro-plastic (MP) only in 60 minutes with high kinetics as quantified by dynamic light scattering, UV-vis, and thermogravimetric analysis. Further, in a binary system (solid and dissolved pollutants), 2D [email protected]@FeO successfully removed both MP and methylene blue (MB) in 60 minutes. Zeta potential, ex situ scanning electron microscopy, and x-ray photoelectron spectroscopy analysis and 2nd-order kinetics isotherm supported chemosorption mechanism of removal. 2D [email protected]@FeO showed 6 adsorption cycles reusability with 90% removal capacity. The stability and the pereservance of the structure of 2D [email protected]@FeO after six cycle was proved by ex situ transmission electron microscopy, Brunauer-Emmett-Teller, and Energy-dispersive x-ray spectroscopy. The results suggest a promising pathway to addressing the removal of mixed contaminants from water in a single process and highlighting its potential in resolving critical industrial and domestic wastewater treatment.