| Because of their unique structural features,MOFs are a kind of novel materials that have been received much attention from the scientific community.MOFs have many advantages such as strong designability and easy functionality,making them promising applications in the fields of gas adsorption and separation.Although the appearance of MOFs is relatively later than other conventional materials,nearly twenty thousand kind of materials have been synthesized at the moment.Thus,it is important to conduct systematic analyses of them towards specific applications.Due to the large amounts of MOFs,it is difficult to investigate them only by experimental ways,which can be accomplished by efficient computational approaches.In light of the above considerations,a large database was built from the existing MOFs reported experimentally,and then molecular simulations were performed to study the performance of all these materials for the separations of hydrogen isotopes as well as methane/hydrogen system:1.A large structural database of MOFs was constructed which contains 18130 structures.Considering the experimentally reported structures often have many problems,such as missing atoms,symmetric duplications of atoms and containing solvent molecules,all of them were modified manually to have perfect crystalline structures.At the same time,the structural features of these MOFs were further analyzed,including the information of their pore sizes and free volumes.2.On the basis of the constructed database,a computational study was conducted to screen the good candidates for hydrogen isotopes separation.Using the validated the force fields,GCMC simulations were performed to calculate the separation selectivity of MOFs.The relationships between the materials separation performance and their intrinsic structural properties like porosity,pore volume and metal centers.Finally,we derived the optimal characteristics of high-performance MOFs for hydrogen isotopes separation.3.Using the built MOF database,a large computational screening study was carried out to find the best materials that can have a good separation properties for methane/hydrogen mixture.On the basis the validated force fields,GCMC simulations were performed to study the separation behaviors of these materials.The results indicated that MOFs are superior to conventional materials.The optimal structural features of MOFs were further extracted through systematic structure-property relationship analyses. |
