Tunable band gap and magnetism of the two-dimensional nickel hydroxide

The electronic structures and magnetic properties of two dimensional (2D) hexagonal Ni(OH) 2 are explored based on first-principles calculations. The results reveal that the ground state of the pristine Ni(OH) 2 is a direct semiconductor with antiferromagnetic (AFM) coupling between two nearest Ni atoms. Interestingly, the monolayer Ni(OH) 2 becomes a ferromagnetic (FM) semiconductor under a biaxial compressive strain of 4%. Furthermore, the band gap of monolayer Ni(OH) 2 can be modulated by the different biaxial strains. These tunable electronic structures and magnetic properties of the Ni(OH) 2 monolayer make it a promising candidate for applications in 2D spin-devices. The electronic structures and magnetic properties of two dimensional (2D) hexagonal Ni(OH) 2 are explored based on first-principles calculations.