“…These ternary compounds have a general chemical formula of M n+1 AX n , where M represents early transition metals, n = 1, 2, or 3, A indicates the general group of IIIA or IVA elements, and X represents either nitrogen or carbon. Similar to binary carbide rock salt structures, for every unit cell of these one-layered hexagonal lattice structures, A layers exist between the close-packed M layers, X atoms fill in M octahedral interstitial sites, and M 6 X octahedra share edges with others [ 4 , 5 , 6 , 7 ].…”