In this study, ahybrid Molecular Dynamics – Grand Canonical Monte Carlo simulation is carried outto investigate the storage capacity of methane in a new nanostructure adsorbent called pillared graphene.This new nanostructure is composed of graphene sheets in parallel with vertical carbon nanotubes (CNTs), which act as their holders. The adsorption ability of this new structure is compared tographene sheets to evaluate its potential for methane storage. The results show that in a specific adsorbent volume, applying pillared graphene increases the number of adsorbed methane up to 22 percent in comparison to graphene sheets.Given the application of various isotherm models such as Langmuir, Freundlich, Sips and Toth andcalculation oftheir parameters, it is predicted that methane adsorption on pillared graphene displaysa heterogeneous behavior. Furthermore, the effects of geometry parameters such as CNTs diameter, the number of CNTs and graphene sheets layer spacing on the methane uptake are investigated. The results show that the pillared graphene containing 1 CNT per 30 nm2 graphene sheet areas providesthe best configuration for methane adsorption. This optimum structure is characterized bya small diameter of about0.938 nm and an optimal layer spacing of about 1.2 nm.Finally, our results show that this kind of pillared structure can be suitable for methane storage.

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