Clean and safe energy storage has received remarkable attention through recent years [1,2]. Because of the enormous resources and production of much less pollution than fossil fuels, methane (CH4) as an alternative fuel has been used, for several years. The current methods of storing of CH4 as compressed gas or in the liquid form do not meet the industrial requirements. Therefore, trying to find new ways of storage of CH4 is justified. For example, considerable experimental and theoretical efforts have been devoted to methane storage in nanostructure materials [3,4]. Single wall nanotubes present particular interest because of their great surface area to bulk ratio. It is revealed that, the substitutional doping of hetro atom, can impose considerable changes in the chemical reactivity and hence in the interactions of the nanotubes with foreign atoms or molecules. In this work, we report our study on pristine and Al-doped boron nitride nanotubes (BNNT) as a potential methane storage through density functional theory (DFT) calculations.
