Oxygen‐Mediated Topological Growth of MoS ₂ for Symmetry‐Anisotropy Coengineered Ultrafast Electronic Switching

Abstract

Abstract Anisotropic 2D materials offer transformative potential for directionally programmable electronics, but the fundamental trade‐off between structural symmetry and electronic anisotropy has limited their device applications. Herein, a topological engineering breakthrough is reported that simultaneously achieves pseudo‐ C 6 symmetry and high in‐plane anisotropy in a star‐like monolayer MoS 2 domain. Structural characterization identifies two distinct lattice alignment modes corresponding to the armchair (AC) and zigzag (ZZ) crystallographic orientations, differing by 30° azimuthal rotation, thus enabling angle‐resolved anisotropic transistors with exceptional electron mobilities ( µA C  = 84.06 cm 2  V −1  s −1 , µ ZZ  = 57.80 cm 2  V −1 s −1 ) and widely tunable electronic anisotropy ratios ( I AC / I ZZ ) of up to 10.91. Leveraging this dual symmetry‐anisotropy control, an ultrafast square‐wave generators are demonstrated with orientation‐programmable switching characteristics that achieve only 39 aJ per event energy efficiency. This work provides new insights into symmetry‐anisotropy coengineering in 2D materials, providing a novel platform for designing energy‐efficient, high‐speed switching electronics.