Strong ferromagnetism in hydrogenated monolayer MoS2 tuned by strain

The electronic and magnetic properties of hydrogenated monolayer MoS2 subject to equibiaxial tensile strain are systematically investigated using first-principles calculations. It is shown that at the strain-free state, the hydrogenated MoS2 is an n-type semiconductor with no spontaneous magnetism. As the tensile strain increases, however, a ground-state transition from nonmagnetism to ferromagnetism (FM) occurs with simultaneously enhanced magnetic moment and stability. The maximum FM state is achieved at a strain of 6.6%, which corresponds to Curie temperature T-c of 232 K. As the strain increases further, both strength and stability of the ferromagnetic state weaken and eventually vanish due to the enhanced ionic character in Mo-S bonds and the resulting delocalization of Mo d orbitals. Similar behavior is also predicted in hydrogenated monolayer MoSe2. The present work by combining chemical functionalization and strain engineering provides a route to harness the magnetic properties of two-dimensional transition metal dichalcogenides for spintronic applications.