Numerical study on interactions of atmospheric plasmas and vegetable oils by reactive molecular dynamic simulations

Abstract

Plasma medicine is a rapidly growing multidisciplinary field. Recently, experimental observations have shown that plasma-activated oil (PAO) with high reactive activity can effectively promote wound healing. In this study, a reactive molecular dynamic (MD) simulation is performed to investigate the interactions of reactive oxygen species (ROS), such as O, OH, and O 3 produced in atmospheric plasmas, and fatty acids in vegetable oils with the ReaxFF field. The reaction processes of the chemical bond breaking and formation of fatty acids upon impact by the ROS are deeply explored. The simulation shows that the reactions typically start with the H

Influence of reactive oxygen species concentration and ambient temperature on the evolution of chemical bonds during plasma cleaning: a molecular dynamics simulation

“…The accuracy of ReaxFF in describing reactions between organic molecules and reactive species in plasma has been validated by abundant experiments and simulations. 35–39 In the ReaxFF, the energy of the system is calculated based on the bond order between pairs of atoms, which is divided into various components, as shown in eqn (1): E system = E bond + E under + E over + E val + E pen + E tors + E conj + E vdWaals + E Coulomb where E system is the total energy of the system. E bond denotes the bond order and bond energy.…”

“…This model is widely applied to simulate chemical reactions between plasma and organic molecules. 35–37…”

“…Although the plasma concentration exceeds the actual situation, 42 the setting of the reactive species concentrations is acceptable considering the chemical reaction efficiency. [36][37][38][39] Besides, according to the experimental temperature range of 298 K to 523 K, we performed isothermal plasma cleaning simulations at 300 K to 800 K to explore the inuence of temperature evolution on plasma cleaning characteristics. To speed up the chemical reaction process, relatively high temperatures were selected to study the reaction mechanism.…”

“…32,34 Reactive molecular dynamics (RMD) can accurately describe the chemical bond evolution of hydrocarbon compounds by reactive species in plasma, verified by experimental and simulational studies. 35 Cui et al 36 and Tian et al 37 adopted reactive molecular dynamics to elucidate the reaction pathway of the destruction of biomolecules and the formation of new radicals under the action of reactive oxygen species in the plasma. The simulation results illustrated that OH concentration had an essential effect on the destruction pathway and reaction rate of biomolecules.…”

“…38 The evolution of chemical bonds and the main products obtained by the ReaxFF data are consistent with the X-ray photoelectron spectroscopy (XPS) measurement results during plasma cleaning experiments. In addition, methods to explore chemical reaction pathways using ReaxFF have been reported, including degradation of pesticides, 35 medicine, 37 sterilization, 39 etc. The microscopic mechanism of interaction between organic molecules and reactive species is revealed by RMD, which provides the theoretical basis for applying low-temperature plasma.…”