Two-dimensional, ordered, double transition metals carbides having a nominal unit cell composition M′2M″NXN+1
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′ 2 M″nX n+1 , such that each X is positioned within an octahedral array of M′ and M″; wherein M′ and M″ each comprise different Group 11113, WE, 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 army of crystal cells.
1. A composite, comprising:
a matrix material; and
a crystalline filler composition dispersed within the matrix material,
the crystalline filler composition 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′ 2 M″ n X n+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.
2. The composite of claim 1 , wherein the matrix material comprises a polymer or a glass.
3. The composite of claim 2 , wherein the polymer comprises a liquid crystal polymer.
4. The composite of claim 2 , wherein the glass comprises a silicate glass.
5. The composite of claim 1 , wherein the composite has a flexural strength that is independently at least 5% higher than the flexural strength than that exhibited by an otherwise equivalent, but unfilled material.
6. The composite of claim 1 , wherein the composite exhibits an optical transparency at at least one wavelength in a range of about 250 nm to about 850 nm in a range of from about 0% to at least about 95%.
7. The composite of claim 6 , wherein the composite exhibits an optical transparency at at least one wavelength in a range of about 250 nm to about 850 nm in a range of from about 50% to at least about 95%.
8. The composite of claim 1 , wherein the crystalline filler composition comprises between amounts in the range of about 0.1 wt % to about 90 wt %, relative to the combined weight of the matrix and the crystalline filler.
9. The composite of claim 2 , wherein the polymer comprises an organic polymer.
10. The composite of claim 1 , wherein the composite is in the form of a film, sheet, or ribbon.
11. A method, comprising:
removing substantially all of the A atoms from a compositionally consistent MAX-phase composition having an empirical formula of M′ 2 M″ n AlX n+1 M n+1 AX n ;
wherein M′ and M″ each comprise different Group IIIB, IVB, VB, or VIB metals;
wherein each X is C, N, or a combination thereof,
wherein n=1 or 2, and
wherein the removing effects formation of a crystalline composition 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′ 2 M″ n X n+1 , such that each X is positioned within an octahedral array of M′ and M″;
wherein the M′ atoms are substantially present as two-dimensional outer arrays of atoms within the two-dimensional array of crystal cells; where in the M″ atoms are substantially present as two-dimensional inner arrays of atoms within the two-dimensional array of crystal cells; and wherein 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.
12. The method of claim 11 , wherein at least 50 atomic % of the A atoms are removed from a finally recovered sample, relative to the original MAX phase composition.
13. The method of claim 12 , wherein more than about 70 atomic % of the A atoms are removed from a finally recovered sample, relative to the original MAX phase composition.
14. The method of claim 11 , wherein the removing is effected by an acid.
15. A crystalline composition 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′ 2 M″ n X n+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; 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; and wherein the two-dimensional outer arrays of atoms contain less than 95 atom % M′ atoms, the balance to 100 atom % being M″ atoms and wherein the two-dimensional inner arrays of atoms contain less than 95 atom % M″ atoms, the balance to 100 atom % being M′ atoms.
16. The composition of claim 15 , wherein the two-dimensional outer arrays of atoms contain less than 98 atom % M′ atoms, the balance to 100 atom % being M″ atoms and wherein the two-dimensional inner arrays of atoms contain less than 98 atom % M″ atoms, the balance to 100 atom % being M′ atoms.
17. The composition of claim 15 , wherein the two-dimensional outer arrays of atoms contain less than 90 atom % M′ atoms, the balance to 100 atom % being M″ atoms and wherein the two-dimensional inner arrays of atoms contain less than 90 atom % M″ atoms, the balance to 100 atom % being M′ atoms.
18. The composition of claim 15 , wherein the two-dimensional outer arrays of atoms contain less than 85 atom % M′ atoms, the balance to 100 atom % being M″ atoms and wherein the two-dimensional inner arrays of atoms contain less than 85 atom % M″ atoms, the balance to 100 atom % being M′ atoms.
19. The composition of claim 15 , wherein M′ is Nb, M″ is V, and X is C, wherein M′ is Ta, M″ is Ti, and X is C, wherein M′ is Ta, M″ is V, and X is C, or wherein M′ is Nb, M″ is Ti, and X is C.