Exploring the potential of Si-decorated graphene for hydrogen storage form a theoretical perspective

Density functional theory (DFT) based calculations have been carried out to explore theadsorption of hydrogen molecule onto the surface of Si-decorated graphene monolayer at the GGA-PBE level of theory. Based on the obtained results, it was found that theinteraction of hydrogen molecule with Si-decorated graphene is accompanied by the release of notable amount of energy (-0.16 eV/H2) which is within the range of strong physisorption together with the transfer of considerable amount of electrons (0.13 e for eight hydrogen molecules) and short binding distance. Indeed, the substitution of Si atom with the carbon at the surface of graphene, makes the Si atom to act as the positive center which enhances the adsorption of hydrogen onto this modified monolayer. We found thatup to 8 H2 molecules can stably interact with Si atom on the graphene sheet with desirable adsorption energy which indicates that this Si-decorated monolayer facilitates the hydrogen storage at near ambient conditions for practical applications. This newly developed Si decorated graphene with its high hydrogen storage capacity would be an excellent candidate for hydrogen storage applications.

کلیدواژه ها:

Hydrogen ، Adsorption ، DFT ، Graphene ، Si-decorated