Monte Carlo simulations of hydrogen adsorption in fullerene pillared graphene nanocomposites

Abstract

The objective of this study is to investigate the hydrogen storage performances of three-dimensional periodic fullerene pillared graphene nanocomposites (FPGNs) consisting of covalently bonded fullerene units between graphene layers. Different forms of fullerenes were used as pillars to adjust porosity and enhance the hydrogen storage capacities of the proposed structures. The gravimetric and volumetric hydrogen uptakes of FPGNs were investigated via grand canonical Monte Carlo calculations under both low- and high -pressure (i.e. 0.01-100 bars) and different thermal (i.e. 77 and 298 K) loading conditions. The simulation results showed that a considerable enhancement in hydrogen adsorption performance could be achieved with the appropriate selection of fullerene size and loading conditions. The simulation results revealed that the FPGNs could uptake 10.3 wt.% hydrogen at 77 K. In addition, the deliverable hydrogen storage capacity of FPGNs could overpass 7.8 wt.% for the charge at 77 K, 100 bar and discharge at 160 K, 5 bar conditions which emphasises the potential of the proposed structures as future ultra-lightweight hydrogen storage media.