The effect of different environments on the oxidation of Ti3C2MXene structures is investigated using ReaxFF molecular dynamics simulations and experimental techniques.

This article reviews recent advances in the development of reactive empirical force fields or potentials. In particular, we compare two widely used reactive potentials with variable-charge schemes that are desirable for multicomponent or multifunctional systems: the ReaxFF (reactive force field) and charge-optimized many-body (COMB) potentials. Several applications of these approaches in atomistic simulations that involve metal-based heterogeneous systems are also discussed.

Developing strategies for atomic-scale controlled synthesis of new two-dimensional (2D) functional materials will directly impact their applications. Here, using in situ aberration-corrected scanning transmission electron microscopy, we obtain direct insight into the homoepitaxial Frank–van der Merwe atomic layer growth mechanism of TiC single adlayers synthesized on surfaces of Ti3C2 MXene substrates with the substrate being the source material. Activated by thermal exposure and electron-beam irradiation, hexagonal TiC single adlayers form on defunctionalized surfaces of Ti3C2 MXene at temperatures above 500 °C, generating new 2D materials Ti4C3 and Ti5C4. The growth mechanism for a single TiC adlayer and the energies that govern atom migration and diffusion are elucidated by comprehensive density functional theory and force-bias Monte Carlo/molecular dynamics simulations. This work could lead to the development of bottom-up synthesis methods using substrates terminated with similar hexagonal-metal surfaces, for controllable synthesis of larger-scale and higher quality single-layer transition metal carbides.