Modeling and Experimental Analysis of Vertical and Lateral Growth of 2D Mo2C Crystals via Chemical Vapor Deposition

This study investigates the growth of Mo2C crystals through Chemical Vapor Deposition (CVD) on Cu substrates. The research combines theoretical and experimental approaches to examine both the vertical and lateral growth of Mo2C crystals. A physico-mathematical model is developed, incorporating bulk and surface diffusivities, as well as solubility gradients for Mo2C crystal growth. Nonlinear flow equations are used to predict Mo2C crystal growth rates in vertical and lateral directions within the Mo-, Cu-, Mo2C layer framework. The model correlates the height and diameter of the Mo2C crystals with the thickness of the copper layer and time, which is then validated through experiments and imaging techniques such as SEM and AFM. The results highlight the significant influence of the copper layer thickness on the height of Mo2C crystals, while its impact on the lateral dimensions is less critical. The study goes beyond enhancing Mo2C crystal growth and explores the synthesis of tailored Mo2C crystals for specific applications. The developed forward model provides a platform for further advancements and exploration of related material analogs.<br/>(This material is based on the work supported by the Air Force Office of Scientific Research (award numbers: FA9550-19-1-7048, FA9550-22-1-0358).