Effect of Fe-O ReaxFF on Liquid Iron Oxide Properties Derived from Reactive Molecular Dynamics

Leon C. Thijs, Efstratios M. Kritikos, Andrea Giusti, Marie Aline van Ende, Adri C.T. van Duin, Xiao Cheng Mi

Research output: Contribution to journalArticlepeer-review

Abstract

As iron powder nowadays attracts research attention as a carbon-free, circular energy carrier, molecular dynamics (MD) simulations can be used to better understand the mechanisms of liquid iron oxidation at elevated temperatures. However, prudence must be practiced in the selection of a reactive force field. This work investigates the influence of currently available reactive force fields (ReaxFFs) on a number of properties of the liquid iron-oxygen (Fe-O) system derived (or resulting) from MD simulations. Liquid Fe-O systems are considered over a range of oxidation degrees ZO, which represents the molar ratio of O/(O + Fe), with 0 < ZO < 0.6 and at a constant temperature of 2000 K, which is representative of the combustion temperature of micrometric iron particles burning in air. The investigated properties include the minimum energy path, system structure, (im)miscibility, transport properties, and the mass and thermal accommodation coefficients. The properties are compared to experimental values and thermodynamic calculation results if available. Results show that there are significant differences in the properties obtained with MD using the various ReaxFF parameter sets. Based on the available experimental data and equilibrium calculation results, an improved ReaxFF is required to better capture the properties of a liquid Fe-O system.

Original languageEnglish (US)
Pages (from-to)10339-10355
Number of pages17
JournalJournal of Physical Chemistry A
Volume127
Issue number48
DOIs
StatePublished - Dec 7 2023

All Science Journal Classification (ASJC) codes

  • Physical and Theoretical Chemistry

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