Large-scale simulations of CO_(2) diffusion in metal-organic frameworks with open Cu sites  

作　　者：Tongan Yan Minman Tong Qingyuan Yang Dahuan Liu Yandong Guo Chongli Zhong 

机构地区：[1]State Key Laboratory of Organic-Inorganic Composites,Beijing University of Chemical Technology,Beijing 100029,China [2]School of Chemistry and Materials Science,Jiangsu Normal University,Xuzhou 221116,China [3]College of Mathematics Science,Bohai University,Jinzhou 121013,China [4]State Key Laboratory of Separation Membranes and Membrane Processes,Tiangong University,Tianjin 300387,China

出　　处：《Chinese Journal of Chemical Engineering》2022年第2期1-9,共9页中国化学工程学报（英文版）

基　　金：supported by National Key Research and Develop-ment Program of China(2016YFB0600901);the Natural Science Foundation of China(22038010,21878229,22078024 and 21978005).

摘　　要：Understanding CO_(2) diffusion behavior in functional nanoporous materials is beneficial for improving the CO_(2) adsorption,separation,and conversion performances.However,it is a great challenge for studying the diffusion process in experiments.Herein,CO_(2) diffusion in 962 metal–organic frameworks(MOFs)with open Cu sites was systematically investigated by theoretical methods in the combination of molecular dynamic simulations and density functional theory(DFT)calculations.A specific force field was derived from DFT-D2 method combined with Grimme’s dispersion-corrected(D2)density functional to well describe the interaction energies between Cu and CO_(2).It is observed that the suitable topology is conductive to CO_(2) diffusion,and 2D-MOFs are more flexible in tuning and balancing the CO_(2) adsorption and diffusion behaviors than 3D-MOFs.In addition,analysis of diffusive trajectories and the residence times on different positions indicate that CO_(2) diffusion is mainly along with the frameworks in these MOFs,jumping from one strong adsorption site to another.It is also influenced by the electrostatic interaction of the frameworks.Therefore,the obtained information may provide useful guidance for the rational design and synthesis of MOFs with enhanced CO_(2) diffusion performance for specific applications.

关 键 词：Metal-organic frameworks Open Cusites Molecular simulations Carbon dioxide DIFFUSION 

分 类 号：X701[环境科学与工程—环境工程]