Chemical Vapor Deposition Growth of Highly Stable Layered Antiferromagnetic Oxyhalide "CrOCl"

Layered oxyhalide magnetic materials have recently emerged as one of the most promising material systems in the field of spintronics and quantum devices because of their large optical anisotropy, magnetic phase transition associated with structural changes, strong antiferromagnetism coupled with weak interlayer bonding and high environmental stability. Despite their attractive magnetic properties and outstanding environmental stability, bottom-up approaches for scalable growth remain limited due to presence of coexisting phases with different stoichiometry in their phase diagram.This work presents the first synthesis of environmentally stable ultra-thin flakes of oxyhalide magnetic CrOCl on Mica and Sapphire substrates using CrCl¬3 and KMnO4 as precursor materials through Atmospheric-Pressure Chemical Vapor Deposition (APCVD) technique in the presence of Argon carrier gas. Comprehensive characterization techniques such as Scanning Electron Microscopy (SEM), Energy Dispersive Spectroscopy (EDS) and X-ray Diffraction (XRD) were employed to confirm the stoichiometry and crystallinity of the grown CrOCl flakes. The findings of the work revealed that the quality of the CrOCl flakes depends on the concentration of the oxygen radicals provided by KMnO4 precursor and substrate temperature. Moreover, morphology and the phase of the material are strongly affected by a variety of factors such as the carrier gas flow rate, the growth time, and the growth temperature. Overall, this work expands the fundamental understanding of the bottom-up growth mechanisms involved in synthesizing such materials thereby contributing to the expansion of the library of stable magnetic oxides with potential applications in advanced technological devices.