Highly efficient capturing and adsorption of cesium and strontium ions from aqueous solution by porous organic cage: A combined experimental and theoretical study

Abstract In recent years, porous organic cages (POCs) have attracted considerable interests due to their nanoscale cavities and high surface area. In this study, the combined computational and experimental investigations were performed on POCs to examine their potential capabilities for the removal of Cs+ and Sr2+ ions from aqueous solution. CC3-R with interconnected tetrahedral pores is permeable to water. It has the ability to extract 1.86 mmol g−1 Cs+ (two ions per cage) and 2.77 mmol g−1 Sr2+ (three ions per cage) with distribution coefficients of 1.1 × 104 ml g−1 and 2.4 × 104 ml g−1, respectively. We have used computational methods to calculate the binding energies, strain energies and free energy perturbation (FEP). Effects of contact time and metal ion concentration on the removal of these ions, and extraction capacity of CC3-R for metal ions were examined in detail. Our simulation results are in reasonable agreement with the experimental reports. Thus, our simulation results plays an important role in the proper evaluation of solid phase extraction (SPE) with CC3-R cage.