Moiré Superlattice Characteristics in Bilayer MoS₂ with Wide-Range Twist Angles Enabled by Hydrogen-Driven Kinetic Modulation.

Abstract

Twisted bilayer two-dimensional materials offer a compelling platform for exploring strongly correlated physics and developing next-generation quantum devices, yet their controllable synthesis remains a formidable challenge. Here, we report a hydrogen-perturbation-assisted chemical vapor deposition strategy for the scalable and probabilistic regulation of twisted bilayer MoS₂ (TB-MoS₂) with tunable twist angles ranging from 0° to 120°. By precisely modulating hydrogen introduction kinetics supported by gas-flow and thermal-field simulations, we reveal that H₂ perturbation effectively disrupts thermodynamic equilibrium. This alters microenvironmental kinetics, enabling twisted nucleation and significantly improving the yield of TB-MoS₂ with incommensurate twist angles. Electrical characterization of the field-effect transistors (FETs) uncovers a distinct correlation between Moiré superlattice configurations and charge transport dynamics. Specifically, devices with intermediate twist angles (near 30°) exhibit quasi-Ohmic behavior and superior carrier mobilities compared to their counterparts at thermodynamically preferred 0° and 60° orientations. This enhancement is attributed to weakened interlayer coupling in near 30° Moiré superlattices, which minimizes interlayer scattering and facilitates efficient carrier transport. These findings not only demonstrate a reliable approach for growing high-quality TB-MoS₂ but also unveil the tunability of its electrical properties via twist-angle engineering, offering a promising pathway for advancing the design of 2D-material-based electronic and quantum devices.