LAUSR

Abstract Two-dimensional (2D) intrinsic ferromagnetic materials with high Curie temperature have attracted increasing research interest because of their potential applications in spintronics. Here, on the basis of first principles calculations combined with Monte Carlo simulation, we report a new 2D pentagon-based monolayer, penta-MnN2, which is not only dynamically, mechanically and thermally stable, but also exhibits half-metallicity with a band-gap of 1.12 eV in spin-down channel. More interestingly, penta-MnN2 displays a high Curie temperature TC of 913 K that can be further improved to 956 K when the biaxial tensile strain of 3% is applied. Compared to the reported hexagonal MnN monolayer, the exchange interaction between the Mn atoms is significantly enhanced in the penta-MnN2 sheet due to its unique geometric configuration composed solely of the pentagons containing N2 dimers.