Interfacial work-function engineering for giant tunneling electroresistance in a Sc(2)CO(2)/Y(2)CO(2)van der Waals ferroelectric tunnel junction.

Van der Waals ferroelectric tunnel junctions (FTJs) based on two-dimensional (2D) materials offer a promising platform for next-generation nonvolatile memory, yet achieving ultrahigh tunneling electroresistance (TER) remains a critical challenge. This work demonstrates a giant TER effect of 5.83 × 10% in a vertically stacked FTJ comprising out-of-plane ferroelectric monolayers ScCOand YCO. First-principles calculations and quantum transport simulations reveal that the TER originates from interfacial work-function engineering. In thestate, a substantial work-function difference Δ= 2.35 eV drives significant charge transfer and yielding high conductance. Conversely, theconfiguration exhibits a smaller Δ(0.85 eV), insufficient to overcome the ScCOband gap. These findings not only propose ScCO/YCOas an exceptional candidate for high-performance memory devices but also establish a general interfacial design strategy for achieving colossal TER in low-dimensional ferroelectric systems.