Soot formation of n-decane pyrolysis: A mechanistic view from ReaxFF molecular dynamics simulation

[Display omitted] •The formation of the soot nanoparticle undergoes four processes.•Initial pyrolysis provides the reactant source for the formation of soot precursor.•The soot particle undergoes the surface growth and the morphological rearrangement.•Higher temperature can accelerate the formation of soot particle. The chemical-kinetic mechanism of soot formation for the n-decane pyrolysis was comprehensively investigated from theoretical perspective. We found the formation of carbonaceous nanoparticle with a multi-layer closed cylindrical structure needs four processes including initial rings formation, PAH growth, particle nucleation via coalescence of PAH and particle growth by coagulation or surface reactions. The mechanisms of HACA, CAHM and CHRCR play crucial roles in the processes of the formation and growth of PAH molecules. In addition, the temperature effect was discussed and found the higher temperature can accelerate the formation of soot particle, which is in agreement with the experiment findings.