Gate-Tunable Schottky Diodes in MoS2/TiSe2 van der Waals Heterostructures

The integration of two-dimensional (2D) van der Waals (vdW) metals with semiconductors offers unprecedented opportunities to engineer atomically sharp heterointerfaces with tailored electronic properties. Here, we demonstrate a high-performance Schottky junction by integrating TiSe 2 ─a high-work-function 2D metal (φ ≈ 5.4 eV)─with MoS 2 to form a metal–semiconductor vdW heterostructure. This interfacial design creates a substantial Schottky barrier height (SBH ≈ 240 meV) at the metal–semiconductor interface, enabling robust diode-like rectification with a high rectification ratio (>10 7 ) and ultralow reverse leakage current (∼10 –13 A) at room temperature. The device exhibits exceptional gate controllability, achieving near-ideal thermionic emission characteristics (ideality factor n ≈ 1.4) and dynamic switching between rectifying and Ohmic regimes via electrostatic doping. Our work advances the fundamental understanding of 2D vdW Schottky physics, demonstrating their potential for adaptive nanoelectronics such as reconfigurable logic circuits and energy-efficient rectifiers.