Onset of catalytic activity of graphene nanosheets in reaction with energetic materials evaluated by ReaxFF molecular dynamics simulation

A computational strategy based on ReaxFF reactive force field unravels details of the combustion of 1,3,5-trinitroperhydro-1,3,5-triazine/graphene (RDX/GR). This method allows us to resolve the evolution of species and structures, as well as the catalytic mechanism of GR. A comparative analysis of decay rate in RDX (pure RDX, RDX/GR, and RDX/porous GR) demonstrates that the catalytic activity of GR is dependent on the density and temperature. The wrinkled graphene formed by thermal fluctuation and extrusion in the initial stage has more significant catalytic activity. O, OH, and NO tend to bond to the dangling sp C atoms in the wrinkled graphene. In combustion catalysis, GR accelerates the interatomic exchanges between active groups on GR and RDX. However, the atomic exchange hardly damages the integrity of the carbon nanosheets. The density functional theory method further verified that the active groups are adsorbed on graphene. The sorption energy of NO attached to the convex of wrinkled GR is 2.79 kcal/mol higher than that on the flat GR. Our findings shed light on the complicated interplay between combustion catalysts and energetic materials.