Tunable Electronic Properties and Contact Performance of Type-II HfS2/MoS2 Van der Waals Heterostructure

Recently, the assembly of van der Waals heterostructures (vdWH) has proved to be an effective strategy to alter the properties and enhance the functionality of multifunctional devices based on 2D materials. Herein, first-principles calculations are employed to construct the (Formula presented.) / (Formula presented.) vdWH, exploring its electronic properties, contact characteristics, and the impact of electric gating. The (Formula presented.) / (Formula presented.) vdWH is predicted to be structurally, thermally, and mechanically stable. The (Formula presented.) / (Formula presented.) vdWH leads to a reduction in the bandgap compared to the constituent components, potentially enhancing optical absorption. Furthermore, the (Formula presented.) / (Formula presented.) heterostructure forms the type-II band alignment, localizing electrons and holes predominantly in the (Formula presented.) and (Formula presented.) layers, respectively. Such type-II (Formula presented.) / (Formula presented.) heterostructure makes it promising candidate for the optoelectronic devices, benefiting from the spatial separation of photogenerated electron-hole pairs. Notably, the electronic properties and contact characteristics of the (Formula presented.) / (Formula presented.) vdWH are controllable under electric gating. The negative electric gating facilitates to a transformation from type-II to type-I band alignment, while the positive electric field induces a shift from semiconductor to metal in the (Formula presented.) / (Formula presented.) vdWH. This findings can provide valuable insights into the fundamental aspects that contribute to the exceptional performance observed in (Formula presented.) / (Formula presented.) vdWH toward high-performance multifunctional devices. © 2024 Wiley-VCH GmbH.