利用基于密度泛函理论的第一性原理计算研究了不同层数MoS2和VS2堆垛形成的范德瓦耳斯异质结的电子结构和光学性能。通过从头算分子动力学验证了两种异质结在室温下的稳定性。此外, 两种异质结均显示p型肖特基接触, 但相较于单层MoS2构成的异质结, 在双层MoS2和VS2堆垛形成的异质结中, 势垒高度从0.36 eV显著降低到0.08 eV, 有效地形成了低接触电阻, 有助于降低载流子输运损失的能量。光吸收光谱的计算表明, 双层MoS2构成的异质结具有更高的吸收峰值。研究成果对基于MoS2的异质结设计以及在高性能光电器件方面的应用提供了理论依据。

The electronic structure and optical properties of van der Waals heterostructures with different layers of MoS2 and VS2 stacks were studied by first-principles calculations based on density functional theory. The stability of two heterojunctions at room temperature was verified through ab initio molecular dynamics. In addition, both heterojunctions exhibit p-type Schottky contact. But compared to the heterojunction composed of monolayer MoS2, the barrier height in the heterojunction formed by the stacking of bilayer MoS2 and VS2 significantly decreases from 0.36 eV to 0.08 eV, effectively forming a low contact resistance and reducing the energy loss of carrier transport. The calculation of the light absorption spectrum indicates that the heterojunction composed of bilayer MoS2 has higher absorption peaks. The research results provide a theoretical basis for the design of heterojunctions based on MoS2 and their applications in high-performance optoelectronic devices.