Intercalation-Induced Disintegrated Layer-By-Layer Growth of Ultrathin Ternary Mo(TeS) 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(TeS) plates by a facile chemical vapor deposition method. Adding S powders in the precursors can result in the products varying from well-faceted MoTe hexagonal plates to irregular Mo(TeS) plates with randomly stacked nanometer-thick layer steps. Moreover, their lateral dimension increases from several μm for binary MoTe to several tens of μm for ternary Mo(TeS). More interestingly, such irregular Mo(TeS) 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 S intercalations play an important role in the growth and exfoliation of ultrathin Mo(TeS) 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.