Topochemical synthesis of phase-pure Mo2AlB2 through staging mechanism.

Phase-pure Mo2AlB2 with a single Al layer, a possible precursor for MBenes, was synthesized topochemically by the removal of an Al layer from MoAlB. Ab initio calculations predicted the sequential staging transformation from MoAlB through Mo4Al3B4 (stage II) to Mo2AlB2 (stage I).