Full Article URL:
In this work, we analyzed the CVD growth mechanism of 2D MoSe2. Samples were quenched halfway through a typical CVD growth process and compared to those that were slowly cooled to completion. The intermediate phases in the quenched samples were then analyzed. Based on the co-existence of MoSe2, aligned nanoparticles (APs) at the crystalline edges of MoSe2, and randomly distributed nanoparticles (RPs), as well as evidence of an in-plane “feedstock” and MoSe2 nucleation from the RPs, we developed a three-step growth model and proposed chemical reactions for each step, which were corroborated by molecular dynamics simulations. The first model of the CVD growth process of TMDCs has thus been developed. Furthermore, the growth of MoSe2 was shown to be a reversible reaction, where the MoSe2 edges recede during the slow cooling process.