Catalytic activity of graphene and hydroxy graphene nanosheets in the pyrolysis of CL-20 by ReaxFF-MD simulation

ReaxFF-MD were employed to study the thermal decomposition of the composite structure of CL-20 with graphene and its derivatives. The analysis of the consumption rate of CL-20 shows that the catalytic activity of graphene and its derivatives is related to density and temperature. The increase in reaction temperature accelerates the thermal decomposition of CL-20, while the increase of density inhibits the initial decomposition. The addition of graphene did not alter the main decomposition pathway of CL-20. The main decomposition products of CL-20 are N₂, H₂O, and CO₂, among which N₂ is the most abundant and its generation rate depends on the density. The order of N₂ formation rate at different densities is N_N2 (0.8 V₀) > N_N2 (0.9 V₀) > N_N2 (V₀). The formation of sp³ carbon atoms at the peaks and valleys on graphene have a significant catalytic effect. The increase in temperature and compression density led to the appearance of additional pores on the wrinkled GR, GR(p), and G-OH sheets, forming dangling sp² carbon atoms. The formation of these defect structures enhanced the adsorption of intermediates and free radicals on graphene sheets and accelerated the interatomic exchange between active groups. However, atomic exchange hardly damages the integrity of the graphene layer.