Hydrogen abstraction/addition reactions in soot surface growth

Abstract

The surface diffusion-induced reaction accounts for the unexpected high reaction rates in the cases of soot formation.

Molecular Dynamics Study on the Condensation of PAH Molecules on Quasi Soot Surfaces

“…The C/H ratio of this PAH cluster is 2.0 and it falls within the range of nascent soot particles. 42 As shown in Figure 1, the initial distances between coronene molecules are optimized (L = 10.2 Å and d = 3.3 Å, according to ref 41), to ensure the minimum potential energy of the initial configuration of the quasi soot surface. Combining with the periodic boundary conditions (PBCs) in x and y directions, the surface would be extended to infinite.…”

“…On the other hand, because a gas-phase PAH molecule is much smaller than an over 10 nm PAH cluster, it may be reasonable to approximate the surface of the cluster as an infinite plane. Therefore, in this work, coronene (C 24 H 12 ) molecules are stacked at the bottom of the simulation box to represent the surface of an over 10 nm PAH cluster, similar to the model in ref . The C/H ratio of this PAH cluster is 2.0 and it falls within the range of nascent soot particles .…”

“…In order to prevent the evaporation of stacked coronene molecules at high temperatures, atoms located at the lowest layer are frozen. This method was often used in previous MD research. ,, For example, Chu et al employed this infinite stacked coronene plane to investigate the surface hydrogen abstraction/addition reactions and found that the bottom restraint had little influence on the kinetic energy transfer between the surface and the incident object. Further, the validity of the approximation of an infinite surface will be discussed later.…”

“…C/H/O ReaxFF has achieved popularity for the research related to hydrocarbon combustion, such as syngas combustion, graphene oxidation, soot inception, , and carbon-based material synthesis for electrical energy storage . Hence, we use the force field that has been validated in Chu et al, Mao et al, and Mao . According to Mao et al and Mao, the ReaxFF can well predict both the energy barriers of the H abstraction reactions of coronene molecules with H/OH radicals and the dimerization energy of coronene molecules.…”

Nanopartículas de fuligem isoladas agindo como uma fonte eficiente de oxigênio singleto: efeitos da agregação molecular e sua estrutura energética

“…16,36 Sua formação ocorre dentro da "chama", no processo de combustão através da adição de acetileno e abstração de hidrogênio (HACA). 37 As moléculas de HPA são consideradas cancerígenas quando avaliadas individualmente, e sua caracterização óptica já é bem definida, utilizada inclusive, para verificar quais moléculas estariam presentes na fase gasosa da formação da fuligem utilizando a técnica de fluorescência induzida a laser (do inglês -Laser Induced Fluorescence -LIF). [38][39] Neste trabalho, destaca-se o estudo da agregação das moléculas de HPA, forma primária das partículas de fuligem.…”