MoSi 2 N 4 single-layer: a novel two-dimensional material with outstanding mechanical, thermal, electronic and optical properties

Very recently, the 2D form of MoSi 2 N 4 has been successfully fabricated (Hong et al 2020 Science 369 670). Motivated by these recent experimental results, we investigate the structural, mechanical, thermal, electronic and optical properties of the MoSi 2 N 4 monolayer. The mechanical study confirms the stability of the MoSi 2 N 4 monolayer. The Young’s modulus decreases by ∼30%, while the Poisson’s ratio increases by ∼30% compared to the corresponding values of graphene. In addition, the MoSi 2 N 4 monolayer’s work function is very similar to that of phosphorene and MoS 2 monolayers. The electronic structure shows that the MoSi 2 N 4 monolayer is an indirect semiconductor with a band gaps of 1.79 (2.35) eV using the GGA (HSE06) functional. The thermoelectric performance of the MoSi 2 N 4 monolayer has been revealed and a figure of merit slightly larger than unity at high temperatures is calculated. The optical analysis shows that the first absorption peak for in-plane polarization is located in the visible range of the spectrum, therefore, the MoSi 2 N 4 monolayer is a promising candidate for advanced optoelectronic nanodevices. In summary, the fascinating MoSi 2 N 4 monoloayer is a promising 2D material for many applications due to its unique physical properties.