Progress and prospect of theoretical simulation of microporous materials

Abstract

Microporous materials, which refers to the porous materials with pores of less than 2 nm, have been widely used for heterogeneous catalysis, adsorption, separation, gas storage and other numbers of advanced applications. Their high-profile application is mainly focused in the field of energy and environment research, such as the storage and separation of hydrogen, carbon dioxide and methane. According to the compositions and structures, common microporous materials include molecular sieves, porous carbon materials, metal-organic framework compounds (MOF) and microporous organic polymer (MOP). Due to the diversity of element components and structure characteristics, the number of the microporous materials, which can be synthesized in principle, is considerably large. It is impossible to study these materials only by means of experimental methods. With the rapid development of computing power and numerical methods, the theoretical methods used in the studies of microporous materials not only provide the material properties at the molecular level, but also reveal the micro-scale experimental mechanism. Therefore, it is beneficial for establishing the corresponding relationship between the material structures and their properties, leading to promoting the design and development of novel microporous materials. Currently, the accurate theoretical simulations firstly calculate the intermolecular interactions between the key moiety originated from the microporous material and the target molecule through the computational method of quantum chemistry, thereby acquired the potential energy curve of the system. Then the van der Waals interaction parameters of the force field were fitted. Based on the force field, the processes of gas adsorption in the porous materials were simulated by Grand-Canonical Monte-Carlo (GCMC) method. Good agreements between GCMC simulation results and experimental data for adsorption isotherms and heats of adsorption have been observed in many studies. This paper reviews the theoretical methods recently used in the study of the various microporous materials and the latest theoretical research findings. Moreover, the main problems, development prospects and the direction for future research in the study of microporous materials are pointed out.