Effect of structures on the adsorption performance of Cobalt Metal Organic Framework obtained by microwave-assisted ball milling

Highlights: • Co-MOFs were obtained by microwave assisted ball milling without organic solvents. • Two kinds of Co-MOFs with different structures and adsorption were obtained. • The maximum adsorption capacity of the Co-MOFs toward Congo red reached 4885.20 mg/g. • Co-MOFs show their potential application for removal of CR from aqueous solution. The Co-MOFs were efficiently and low-costly synthesized by microwave-assisted ball milling without organic solvents and the adsorption of Congo Red (CR) was studied in view of adsorption kinetic and isotherm. It's find that the formation of two different structures due to the change in the molar ratio of the raw material, which contribute to a larger difference of the adsorption. The maximum adsorption capacity of the Co-MOFs toward CR reached 4885.20 mg/g. Open active metal sites and π-π stacking interactions are thought to play an important role in the adsorption of CR onto the Co-MOFs.