Substitutional transition metal doping in MoSi2N4 monolayer: structural, electronic and magnetic properties

Abstract

Monolayer MoSi₂N₄ (MoSiN) was successfully synthesized last year [Hong et al., Science369, 670 (2020)]. The MoSiN monolayer exhibited semiconducting characteristics and exceptional ambient stability, calling for more studies of its properties. Here, we conduct first-principle calculations to examine the structural, magnetic, and electronic properties of substitutional doping of MoSiN monolayers with transition metals (TM) at the Mo site (TM–MoSiN). We find that the Sc-, Y-, Ti-, and Zr–MoSiN are metallic systems, while Mn-, Tc-, and Ru–MoSiN are n-type conducting. The Fe–MoSiN is a dilute magnetic semiconductor, and the Ni–MoSiN is a metal (or half-metal). The inclusion of spin–orbit coupling turns them into a half-metal and a semimetal, respectively. We also find that the work function of TM–MoSiN and the bond lengths between the TM and neighbor atoms increase as the atomic radius and electronegativity of the TM atom increase, respectively. The Fe-, Co-, and Ni–MoSiN may be used in spintronic devices, while Mn-, Rh- and Pd–MoSiN could be utilized for spin filter applications.