Theoretical Study Of Non-covalent Interactions Between MOFs And Carbon Nanomaterials

As a new type of organic-inorganic hybrid porous material,MOFs materials have been applied in adsorption and separation,drug delivery,catalysis and other fields due to their structural diversity,high specific surface area,well-developed pores.Due to its unique properties and potential application value,fullerenes have attracted extensive attention in many fields such as chemistry,physics and materials.At present,there have been experimental studies on the adsorption of fullerenes on MOFs materials,because MOFs materials contain metals and have a large number of atoms,traditional density functional theory methods are used to conduct theoretical studies on the non-covalent interaction between MOFs materials and fullerenes,It poses severe challenges to theoretical methods and computer performance,so far,no systematic theoretical research work has been published.In this paper,using the GFN2-x TB method developed by Grimme in recent years,the initial structures constructed by IRMOF-1,IRMOF-8 and IRMOF-10 and fullerenes C₆₀,C₇₀and C₈₀are used for structural optimization and frequency calculation,the geometrical structure of the stable complex with minimal energy is obtained and the values of binding energy and thermodynamic function are calculated.By analyzing the thermodynamic function,it can be found that the formation of the complex is a spontaneous and exothermic process,the structure of fullerenes C₆₀,C₇₀and C₈₀only partially enters the IRMOF-1 and IRMOF-8 frameworks more stable than when they completely enter the framework,while they are more stable when in the IRMOF-10 frame and near the corner of the frame.We have successfully used the?B97M-V/def2-SV(P)method to perform the ALMO-EDA energy decomposition analysis of the stable complex.Through the analysis of the ALMO-EDA results,we found that the non-covalent interaction of the complex is dominated by the dispersion interaction,followed by electrostatic interaction.When the fullerenes C₆₀,C₇₀and C₈₀are located outside to inside of the IRMOF-1 and IRMOF-8 frames,the?...?interaction gradually increases,and the proportion of the dispersion interaction to the total attraction energy increases accordingly,the electrostatic interaction the proportion decreases accordingly;When the fullerenes C₆₀,C₇₀and C₈₀are located outside the IRMOF-10 frame to the inside of the frame,the proportion of dispersion interaction first increases and then decreases,and the proportion of electrostatic interaction first decreases and then increases,the possible reason is the interaction between the lone pair of electrons on the frame SBU oxygen and?leads to the decrease of the proportion of dispersion energy and the increases of the proportion of electrostatic energy.