A theoretical study on the electronic property of a new two-dimensional material molybdenum dinitride

• The 2D MoN2 behaves as an indirect band gap semiconductor with the energy gap of ∼0.12 eV.
• The energy gap can be efficiently tuned from 0 to 0.70 eV by small strain.
• The band gap would transfer from an indirect to a direct one when the strain is beyond 5% or −3%.

Motivated by the recent synthesis of bulk MoN2 which exhibits the layered structure just like the bulk MoS2, the monolayered MoN2 exfoliated from the bulk counterpart is investigated systematically by using density-functional calculations in this work. The result shows that the ground-state two-dimensional monolayered MoN2 behaves as an indirect band gap semiconductor with the energy gap of ∼0.12 eV. Subsequently, the external strain from −6% to 6% is employed to engineer the band structure, and the energy gap can be efficiently tuned from 0 to 0.70 eV. Notably, when the strain is beyond 5% or −3%, the two-dimensional monolayered MoN2 would transfer from an indirect band gap to a direct band gap semiconductor. This work introduces a new member of two-dimensional transition-metal family, which is important for industry applications, especially for the utilization in the long-wavelength infrared field.