Tuning the Magnetic Properties of MoS2 Single Nanolayers by 3d Metals Edge Doping

MoS2 nanolayers are versatile systems for new energy technologies such as spintronics and optoelectronic or (electro)catalytic materials, and for current industrial catalytic processes. Using spin-polarized density functional theory (DFT) calculations, we show that the magnetic moment value at edges of 2H MoS2 single nanolayers follows a periodic trend as a function of the 3d metal (Me) dopants (Me = V, Cr, Mn, Fe, Co). The magnetic moment and ordering depend on the Me dopant and also on its location at the M- or S-edge with higher values at M-edge. The maximum values of the magnetic moments are obtained for Me = Mn. In the case of Co-MoS2 single nanolayers, Co atoms located on the M-edge exhibits a weak magnetic moment (0.6-0.7 mu(B)) which may also be considered as a fingerprint of the catalytically active sites located on this given edge. A detailed electronic and structural analysis reveals that a superexchange interaction involves the Me-dopant, S-bridging ligands, and Mo atoms at subedge, particularly on the M-edge. In perspectives, we propose to combine these magnetic edge effects with the two-dimensional morphology of Me-MoS2 single nanolayers for optimizing 2D-MoS2-based nanomagnets.