Atomistic scale investigation of PAH curvature effects on soot oxidation

摘要

Polycyclic Aromatic Hydrocarbons (PAH) form are the basic structure building blocks of a soot particle. The soot particle consists of a network of PAH molecules in a soot particle which may be planar or curved. The oxidation of soot is affected by a variety of factors, ranging from the presence of surface functional groups to the placement and structure of the PAH molecules. Recent studies [give a reference, if allowed] have shown that curved PAH molecules react with O_2 at a higher rate than plane PAH molecules. As such, in this study we try to understand the role, the structure of PAH has on the oxidation behavior of soot. For this purpose, we use atomistic-level molecular dynamics (MD) simulations with the ReaxFF force field to study the reactivity of Pyrene (representative of planar PAHs) and coroannulene (representative of curved PAHs) in the presence of 02 molecules. To highlight the role of PAH curvature on soot oxidation we compare reaction rates of the representative PAH and examine reaction pathways to understand the preferred favored pathways in the reaction mechanisms.