Intercalation-Induced Disintegrated Layer-By-Layer Growth of Ultrathin Ternary Mo(Te_1-S)₂ Plates

Nanometer-thick transition-metal dichalcogenides (TMDs) have attracted increasing research interest because of their exotic physical properties, but their high-yield and large-scale synthesis remains a challenge for their practical device applications. In this study, we realize the high-yield synthesis of nanometer-thick single-crystalline Mo(Te_1-S)₂ plates by a facile chemical vapor deposition method. Adding S powders in the precursors can result in the products varying from well-faceted MoTe₂ hexagonal plates to irregular Mo(Te_1-S)₂ plates with randomly stacked nanometer-thick layer steps. Moreover, their lateral dimension increases from several μm for binary MoTe₂ to several tens of μm for ternary Mo(Te_1-S)₂. More interestingly, such irregular Mo(Te_1-S)₂ plates can form few layers by ultrasonic exfoliation. Our detailed electron microscopy analyses show that three kinds of S forms influence the ternary growth. In particular, elemental S₈ intercalations play an important role in the growth and exfoliation of ultrathin Mo(Te_1-S)₂ plates. This study enriches the fundamental understanding of zero-valent intercalation in TMDs and provides a new insight into secure high-yield nanometer-thick TMDs, which is critical for practical applications.