Molecular Simulation of Graphene Growth Reactions at Various Temperatures Derived from Benzene in Coal Tar Aromatic Hydrocarbons

Coal tar, a by-product of the pyrolysis of coal, is rich in aromatic compounds that have the potential to facilitate the synthesis of graphene, a high-quality carbon material, via low-temperature chemical vapor deposition (CVD). This approach offers a promising avenue for the cost-effective and large-scale industrial production of graphene while minimizing energy consumption. Nevertheless, there is a paucity of research focused on the low-temperature synthesis mechanisms of graphene derived from aromatic compounds in the context of graphene growth. To achieve high-quality graphene synthesis from coal tar and its aromatic constituents at reduced temperatures, a comprehensive investigation into the reaction pathways of these aromatic compounds is essential. In this study, we meticulously simulate the pyrolysis of benzene, a key aromatic component of coal tar, across various temperature settings utilizing reactive force field (ReaxFF) methodology. Furthermore, we apply density functional theory (DFT) calculations, executed through the Vienna Ab initio Simulation Package (VASP), to assess the dehydrogenation energy associated with the adsorption of benzene on vapor-deposited copper foils. Our molecular dynamics simulations, enhanced by a mixed force field approach, revealed that the dehydrogenated benzene ring (C 6 intermediate) acts as a critical precursor for graphene synthesis. This research significantly elucidates the reaction pathways of aromatic benzene in coal tar through molecular simulations conducted at different temperatures, both in the gas phase and on solid copper foil substrates.