MoSi2N4/WO2 van der Waals heterostructure: Theoretical prediction of an effective strategy to boost MoSi2N4′s nanoelectronic and optoelectronic applications

Recently, MoSi2N4 layer, a new species of two-dimensional (2D) materials, has attracted considerable attention. Nanoelectronic and optoelectronic applications are two of the most promising applications of 2D materials. Herein, via density functional theory (DFT) calculations, we proposed a MoSi2N4/WO2 van der Waals heterostructure (vdWH) to boost 2D MoSi2N4′s nanoelectronic and optoelectronic applications. Primary results are listed below. (a) The MoSi2N4/WO2 vdWH has a good dynamical stability, and its formation is an exothermic process. (b) Interestingly, MoSi2N4/WO2 vdWH displays a typical type-II band alignment, which is beneficial for the separation of photogenerated electron-hole pairs, but it was missed in MoSi2N4 layer. (c) In particular, its type-II band alignment is independent of its stacking model. (d) In contrast with the electron mobility of 1330 cm2 V−1 s−1 of MoSi2N4 layer, the value of MoSi2N4/WO2 vdWH can reach up to 2370 cm2 V−1 s−1. (e) In addition, we also observed that, compared with MoSi2N4 layer, MoSi2N4/WO2 vdWH can display enhanced absorption abilities for both visible and ultraviolet lights. These findings manifest that construction of MoSi2N4/WO2 vdWH is an effective method to improve MoSi2N4 layer’s nanoelectronic and optoelectronic applications.