Dirac State in the FeB₂ Monolayer with Graphene-Like Boron Sheet

By introducing the commonly utilized Fe atoms into a two-dimensional (2D) honeycomb boron network, we theoretically designed a new Dirac material of FeB₂ monolayer with a Fermi velocity in the same order of graphene. The electron transfer from Fe atoms to B networks not only effectively stabilizes the FeB₂ networks but also leads to the strong interaction between the Fe and B atoms. The Dirac state in FeB₂ system primarily arises from the Fe d orbitals and hybridized orbital from Fe-d and B-p states. The newly predicted FeB₂ monolayer has excellent dynamic and thermal stabilities and is also the global minimum of 2D FeB₂ system, implying its experimental feasibility. Our results are beneficial to further uncovering the mechanism of the Dirac cones and providing a feasible strategy for Dirac materials design.