Robust half-metallic ferromagnetism in Cr3C2 MXene

Herein we report an intrinsic ferromagnetism in two-dimensional layered Cr3C2 material. The calculations based on the density-functional theory reveal that in a single Cr3C2 unit three Cr atoms are ferrimagnetically coupled, while the coupling between Cr3C2 units are ferromagnetic with a magnetic moment of 3.9μB/unit. The energy difference between the ferromagnetic and antiferromagnetic configurations is larger than 344 meV per unit, indicating the observed ferromagnetic ordering is robust. Additionally, this ferromagnetic coupling can be enhanced under the external tensile strain. At the strain rising to 0.03, the Cr3C2 converts from metallic ferromagnet to half-metallic ferromagnet with the magnetic moment saturating to an integer value of 4.0μB/unit, and this half-metallic behavior can be maintained for larger strains. Our results highlight a new promising graphene-like half-metallic ferromagnetic material for nanoscale spintronic applications.