CARBON DIOXIDE ADSORPTION ON [HKUST-1] METAL-ORGANIC FRAMEWORK DOPED WITH LITHIUM CATION USING MOLECULAR SIMULATION

Metal-organic frameworks (MOFs) have attracted much attention as adsorbents for the separation of CO2 from flue gas or natural gas. Grand canonical Monte Carlo (GCMC) simulations and density functional theory (DFT) calculations were performed to study the effect of Li-doping on carbon dioxide adsorption over copper-based metal–organic frameworks (MOFs). In this work, a new Li-doping structure, Cu-BTC-Li, was theoretically constructed by introducing Li above of the organic linkers in Cu-BTC. Compared to the original Cu-BTC, Cu-BTC-Li shows higher carbon dioxide capacity and more continuous adsorption behavior in the measured pressure range. It can be attributed to the new adsorption sites (Li-sites) created by Li cations. As a result, the GCMC simulations show that the presence of the Li caions significantly enhances the carbon dioxide storage capacity and this study suggests that Li doping is a possible way for making MOFs effective as carbon dioxide storage materials.