MIM‐Diode‐Like Rectification in Lateral 1T/1H/1T‐MoS ₂ Homojunctions via Interfacial Dipole Engineering

ABSTRACT Lateral 2D tunnel diodes that reproduce metal‐insulator‐metal (MIM)‐diode‐like rectification without using dissimilar contacts are attractive for scalable nanoelectronics. MoS 2 can exist in both the semiconducting 1H phase and the metallic 1T phase, enabling phase‐engineered homojunctions within a single material. First‐principles electronic structure and quantum transport calculations show that phase‐engineered 1T/1H/1T–MoS 2 homojunctions exhibit pronounced MIM‐diode‐like rectification originating from interfacial charge transfer at asymmetric 1T/1H interfaces. The charge transfer establishes interface dipole steps that impose a built‐in potential drop across the 1H barrier, thereby generating a trapezoidal tunnel barrier at zero bias. In contrast, symmetric 1T/1H interfaces do not form an interface dipoles and show no rectification. To clarify the microscopic origin, a lateral graphene/hexagonal‐boron‐nitride/graphene junction is analyzed as a minimal MIM diode analogue with a simple interface and well‐defined barrier, confirming that interface‐induced dipoles, rather than work‐function difference, enable the effect. The mechanism operates entirely within a single monolayer material system and does not rely on out‐of‐plane stacking, highlighting compatibility with phase patterning in 2D semiconductors. These results establish lateral 1T/1H/1TMoS 2 as a fully 2D, single‐material platform for MIM‐diode‐like rectification and identify the interface‐dipole engineering as a general strategy for designing ultrathin lateral tunnel diodes that can serve as building blocks for high‐frequency detectors and energy‐harvesting devices.