Abstract: Provided are methods for etching MAX-phase materials to produce MXenes, the etching being accomplished by a salt, one or both of a polar and a non-polar solvent, and optionally a crown ether, the etching also being optionally performed in a water-free or essentially water-free manner. Also provided are related systems and methods.

Abstract: Provided are methods to convert—through a bottom-up approach—binary and ternary titanium carbides, nitrides, borides, phosphides, aluminides, and silicides into lepidocrocitic nanofilaments that in some cases self-assemble into 2D flakes by immersing them in a quaternary ammonium solution at moderate temperatures. The resulting flakes can comprise nanofilaments in cross-section, some of which nanofilaments can be few microns long in some instances.

Abstract: The present disclosure describes a crumpled form of Mxene materials, and methods of making and using these novel compositions.

Abstract: The present disclosure describes a crumpled form of Mxene materials, and methods of making and using these novel compositions.

Abstract: Provided are methods of effecting cation exchange in MXene materials so as to stabilize the materials. Also provided are compositions, comprising layered MXene materials that comprise an organic cation between layers. Also provided are MXene compositions comprising a chalcogen disposed thereon, the MXene composition further optionally comprising a quaternary ammonium halide disposed thereon.

Abstract: The present disclosure describes a crumpled form of MXene materials, and methods of making and using these novel compositions.

Abstract: A paste that includes particles of a layered material in an ammonia aqueous solution. The particles include one or plural layers, the layers having a layer body represented by MmXn, wherein M is at least one metal of Group 3, 4, 5, 6, or 7, X is a carbon atom, a nitrogen atom, or a combination thereof, n is not less than 1 and not more than 4, and m is more than n but not more than 5, and a modifier or terminal T exists on a surface of the layer body, wherein T is at least one selected from the group consisting of a hydroxyl group, a fluorine atom, a chlorine atom, an oxygen atom, and a hydrogen atom, wherein the paste has a viscosity of 1 Pa·s or more at a shear velocity of 1/s when the paste has a solid content concentration of 1.0% by mass.

Abstract: 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 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.

Abstract: 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 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.

Abstract: The present invention(s) is directed to novel conductive Mn+1Xn(Ts) compositions exhibiting high volumetric capacitances, and methods of making the same. The present invention(s) is also directed to novel conductive Mn+1Xn(Ts) compositions, methods of preparing transparent conductors using these materials, and products derived from these methods.

Abstract: The present invention(s) is directed to novel conductive Mn+1Xn(Ts) compositions exhibiting high volumetric capacitances, and methods of making the same. The present invention(s) is also directed to novel conductive Mn+1Xn(Ts) compositions, methods of preparing transparent conductors using these materials, and products derived from these methods.

Abstract: Provided herein are MXene-containing photodetectors and related methods. Also provided are MXene-containing THz polarizers as well as MXene-containing MOSFETs, MESFETs, and HEMFETs.

Abstract: The present disclosure describes a crumpled form of MXene materials, and methods of making and using these novel compositions.

Abstract: 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 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,

Abstract: 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.

Abstract: The present invention(s) is directed to novel conductive Mn+1Xn(Ts) compositions exhibiting high volumetric capacitances, and methods of making the same. The present invention(s) is also directed to novel conductive Mn+1Xn(Ts) compositions, methods of preparing transparent conductors using these materials, and products derived from these methods.

Abstract: The present invention(s) is directed to novel conductive Mn+1Xn(Ts) compositions exhibiting high volumetric capacitances, and methods of making the same. The present invention(s) is also directed to novel conductive Mn+1Xn(Ts) compositions, methods of preparing transparent conductors using these materials, and products derived from these methods.

Abstract: The present invention is directed to crystalline solids having an empirical formula of M2A2X, wherein M is at least one Group IIIB, IVB, VB, or VIB metal, preferably Cr, Hf, Sc, Ti, Mo, Nb, Ta, V, Zr, or a combination thereof; wherein A is Al, Ga, Ge, In, Pb, or Sn, or a combination thereof; and each X is CxNy, where x+y=1. In some particular embodiments, the crystalline composition has a unit cell stoichiometry of Mo2Ga2C.

Abstract: The present invention is directed to compositions comprising at least one layer or at least two layers, each layer comprising a substantially two-dimensional array of crystal cells, having first and second surfaces, each crystal cell having the empirical formula of Mn+1Xn, where M, X, and n are described in the specification, and devices incorporating these compositions.

Abstract: 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.