The present disclosure is directed to compositions comprising at least one layer having first and second surfaces, each layer comprising:

a substantially two-dimensional array of crystal cells,

each crystal cell having an empirical formula of M’2M”nXn+1, such that each X is positioned within an octahedral array of M’ and M”;

wherein M’ and M” each comprise different Group IIIB, IVB, VB, or VIB metals;

each X is C, N, or a combination thereof;

n = 1 or 2; and wherein

the M’ atoms are substantially present as two-dimensional outer arrays of atoms within the two-dimensional array of crystal cells;

the M” atoms are substantially present as two-dimensional inner arrays of atoms within the two-dimensional array of crystal cells; and

the two dimensional inner arrays of M” atoms are sandwiched between the two-dimensional outer arrays of M’ atoms within the two-dimensional array of crystal cells.