Electrode materials for magnesium batteries

A magnesium battery electrode comprising:

• a current collector, and
• an electroactive compound in electronic communication with the current collector, the electroactive compound having the formula of Ab′MgaMbXy, and a layered structure,
• wherein
• A is one or more dopants selected from the group consisting of Al, Na, K, Zn, Ag, Cu, and mixtures thereof;
• M is one or more transition metals selected from the group consisting of V, Cr, Mn, Fe, Co, Ni, Cu, Ag, Zr, and mixtures thereof;
• X is one or more anions selected from the group consisting of O, S, Se, F, and mixtures thereof;
• 0≦b′≦2.9;
• 0<a≦2.1;
• 0.5≦b≦2.9;
• 1.5≦y≦5.9;
• and
• the layered structure comprises close-packed anion X lattice, layers of octahedrally-coordinated transition metal M, and layers of fully or partially occupied magnesium sites, wherein the layers of metal M and the layers of magnesium sites alternate;
• provided that the compound is not layered MgaVS2 or layered MgaZrS2.