MSene: A large family of two-dimensional transition metal sulfides with MXene structure

Abstract

In this Letter, we theoretically report a large family of two-dimensional (2D) transition metal sulfides ${M}_{2}\mathrm{S}$ with a MXene structure in the $2H$ and $1T$ phases, which we refer to as MSene. Twenty-four out of fifty-eight MSenes are proved to be stable. Notably, this family includes twelve superconducting (SC) materials, seven SC topological metals (SCTMs), four charge density wave (CDW) materials, and five magnetic materials including one ferromagnetic (FM) and four $A$-type antiferromagnetic (AFM) materials. For example, $2H\ensuremath{-}{\mathrm{Mo}}_{2}\mathrm{S}$ is a SCTM which exhibits a SC critical temperature (${T}_{c}$) of 10.2 K and nontrivial topological properties; $1T\ensuremath{-}{\mathrm{Hf}}_{2}\mathrm{S}$ is a CDW material with the CDW originating from electron-phonon coupling. The CDW can be suppressed by compressive strain, leading to the emergence of superconductivity; $2H\ensuremath{-}{\mathrm{Cr}}_{2}\mathrm{S}$ and $1T\ensuremath{-}{\mathrm{Mn}}_{2}\mathrm{S}$ show FM and $A$-type AFM properties, respectively. Thus, the large family we predicted shows rich physical properties and significantly expands the repertoire of 2D materials. It serves as a platform for investigating the competition or coexistence of multiple orders such as SC, CDW, FM, AFM, and topological orders in 2D materials.

Topics & Concepts