Temperature dependence of the oxidation resistance of the monolayer h-BN：A ReaxFF molecular dynamics study

Hexagonal boron nitride (h-BN) still fails by oxidative decomposition at high temperatures, but the mechanism remains unclear at the atomic scale. In this work, the kinetic behavior of high-temperature oxidation of h-BN was simulated using Reactive Force Field Molecular Dynamics (ReaxFF-MD, RMD), and the decomposition law and products, charge transfer law, etc. were systematically investigated. The simulations reveal that temperature regulates the oxidation pathway, with increase in temperature promotes the adsorption-intercalation of O₂ at the B site, induces a heptagonal intermediate configuration, and triggers the asymmetric consumption of B/N atoms. After O atoms replace B and N atoms, the original hexagonal structure is restored and chain-like BN is formed. The adsorption and insertion of O atoms result in discontinuous O charge distribution, proposing the phenomenon of oxygen atom charge stratification. The transfer of effective charges increases with the increase in B/N-O coordination numbers, and the rise in temperature promotes the transition to higher charge states. This discovery provides a new atomic-level perspective for understanding the charge transfer mechanism of h-BN in an oxidative environment.