Asymmetric XMoSiN[formula omitted] (X=S, Se, Te) monolayers as novel promising 2D materials for nanoelectronics and photovoltaics

Abstract

In this paper, we study asymmetric 2D materials XMoSiN2 constructed and optimized from MoSi2N4 by deleting SiN from one side and replacing remaining N atoms from the same side with chalcogen X atoms (sulfur, selenium, or tellurium). The new structure is a hybrid of a transition metal dichalcogenide and a 2D material from the MoSi2N4 family. We justify the dynamical stability of novel 2D materials. High binding energy (>7.5 eV/atom) is typical for the monolayers under study. Estimated built-in electric field (∼1.3−2 eV/Å) can serve to separate effectively photogenerated charge carriers in the single monolayer. Demonstrated high mechanical strength (2D Young modulus E∼300 N/m, in-plane stress limit >17 N/m), noticeable sensitivity of the electronic and optical properties to deformations of monolayers, and weak sensitivity to an external transverse electric field indicate that the proposed 2D materials are of great promise for applications in flexible opto- and nanoelectronics.