First-principles investigation of the influence of rare earth element doping on the corrosion characteristics of Mg (0001) surface

This study investigates the impact of doping with Al and rare earth elements (REEs) such as Y, La, Ce, Nd, Sm, and Gd on the Mg (0001) surface. Utilizing first-principles calculations, we dissect the alterations in electronic structure, chemical bonding, and adsorption characteristics induced by doping. Our findings reveal that REE doping, characterized by larger atomic radii and lower electronegativity, leads to significant lattice dilation. This dilation strengthens covalent Mg bonds and raises the energy barrier for vacancy formation, enhancing surface stability and reducing vacancy propensity. Moreover, doping markedly affects surface energy and work function, thereby inhibiting anodic dissolution and slowing the hydrogen evolution reaction. Notably, La doping is correlated with a significant improvement in corrosion resistance, a key finding of our research. These results are instrumental for the strategic advancement of Mg alloys with superior stability and corrosion resistance.