Grand Canonical Monte Carlo Simulation Of The Adsorption Of Harmful Gases In Nanoporous Materials

In recent years, the study of nanoporous materials such as metal organic framework and covalent organic framework, become a hot topic of researchers. Due to the excellent characteristics of the two materials such as large surface areas, adjustable pore sizes and controllable properties, as well as acceptable thermal stability, they are widely applied in gas storage, separation, catalyst and pharmacy, etc. Moreover, as a derivative product of graphene, graphene oxide (GO) has attracted resurgent interests. Owing to large amounts of oxygen groups on GO surface, transition metal atoms can be easily supported on the surface, and improve the capacity of GO.In this work, the first-principles computations and Grand Canonical Monte Carlo (GCMC) were performed to investigate the adsorption behaviors of nanoporous materials (MOFs and COFs) and the adsorption/separation capacities of CO in metal supported GO. The main contents are summarized as follows.1. The adsorption properties of CO, NO, and NO2 in several typical nanoporous materials (COF-105, COF-108, MOF-5 and MOF-177) at 298 K were investigated by Grand Canonical Monte Carlo (GCMC) simulations. The adsorption amounts of NO2 in these materials are higher than those of the other three gases because of the stronger gas-sorbent interaction. In particular, NOt adsorption amount in MOF-177 can reach as high as 10.7 mmol/g at 298 K and 10 bar. The interaction between the four gases (H2, CO, NO and NO2) and the COF/MOF adsorbents is further discussed in terms of the isosteric heat.2. The adsorption properties of selected gases (CO, N2, CO2 and CH4) on the Ti-decorated GO surface have been systematically studied by first-principles calculations and GCMC simulations. GCMC simulations of adsorption isotherms further demonstrate that the adsorption amount of CO can reach as high as 7.5 mmol/g at 10 bar and room temperature, the adsorption amount of CO is 2-6 times of the other gases (CO2, N2 and CH4). So the results show that the Ti-decorated GO materials can be ideal sorbents for CO capture and separation from mixtures with N2, CO2, and CH4. In addition to Ti, GO-based materials with other metal decoration may find potential applications for capture and separation of other gases.