STACKED TWO-DIMENSIONAL MATERIALS AND METHODS FOR PRODUCING STRUCTURES INCORPORATING SAME
Structures comprising a first sheet of perforated two-dimensional material and a first plurality of spacer elements disposed between a surface of the first sheet of perforated two-dimensional material and at least one of a surface of a structural substrate and a surface of a second sheet of perforated two-dimensional material are disclosed, as well as related methods. The structures may further comprise a structural substrate, a second plurality of spacer elements, additional sheets of perforated two-dimensional material in direct contact with the first and/or said second sheet of perforated two-dimensional material and/or relief features in the surface of the structural substrate.
1 . A structure comprising a first sheet of perforated two-dimensional material and a first plurality of spacer elements disposed between a surface of said first sheet of perforated two-dimensional material and at least one of a surface of a structural substrate and a surface of a second sheet of perforated two-dimensional material.
2 . The structure of claim 1 , wherein said first plurality of spacer elements is disposed between said surface of said first sheet of perforated two-dimensional material and said surface of said second sheet of perforated two-dimensional material, said structure further comprising a structural substrate disposed on an alternate surface of the first or second sheet of perforated two-dimensional material.
3 . The structure of claim 2 , wherein said first plurality of spacer elements is disposed between said surface of said first sheet of perforated two-dimensional material and said surface of said second sheet of perforated two-dimensional material and a second plurality of spacer elements is disposed between said surface of said structural substrate and said alternate surface of said first or second sheet of perforated two-dimensional material.
4 . The structure of claim 1 further comprising one or more additional sheets of perforated two-dimensional material in direct contact with said first and/or said second sheet of perforated two-dimensional material.
5 . The structure of claim 1 , wherein said first or second sheet of perforated two-dimensional material comprises a graphene or graphene-based film, a transition metal dichalcogenide, α-boron nitride, silicene, germanene, MXene or a combination thereof.
6 . The structure of claim 1 , wherein said first or second sheet of perforated two-dimensional material has an average pore size less than or equal to 4000 angstroms.
7 . The structure of claim 1 , wherein said first or second sheet of perforated two dimensional material comprises randomly distributed pores.
8 . The structure of claim 1 , wherein pores of said first or second sheet of perforated two-dimensional material are chemically functionalized at peripheries of the pores.
9 . The structure of claim 1 , wherein said spacer elements are randomly oriented and positioned.
10 . The structure of claim 1 , wherein a layer of said spacer elements has a thickness selected from a range of 5 angstroms to 10000 angstroms.
11 . The structure of claim 1 , wherein a layer of said spacer element has a substantially uniform thickness.
12 . The structure of claim 1 , wherein a layer of said spacer elements has a non-uniform thickness.
13 . The structure of claim 1 , wherein said spacer elements have average dimensions from 0.5 nm to 200 nm.
14 . The structure of claim 1 , wherein an average areal density of the spacer elements is from 2000 per μm 2 to 1 per μm 2 .
15 . The structure of claim 1 , wherein the spacer elements adhere to the first and/or second sheet of perforated two-dimensional material.
16 . The structure of claim 1 , wherein said spacer elements comprise nanoparticles, nanotubes, nanofibers, nanorods, nanostructures or combinations thereof.
17 . The structure of claim 1 , wherein said spacer elements are selected from the group consisting of single walled carbon nanotubes, multiwalled carbon nanotubes, carbon nanostructures, fullerenes, carbon nanohorns and combinations thereof.
18 . The structure of claim 1 , wherein a layer of said spacer elements has an average surface roughness less than or equal to 50 nm.
19 . The structure of claim 1 , wherein the structural substrate comprises a porous polymer or a porous ceramic.
20 . (canceled)
21 . The structure of claim 1 , wherein the structural substrate has a thickness between 1 μm to 500 μm.
22 . The structure of claim 1 , wherein the structural substrate has a porosity greater than or equal to 3%.
23 . (canceled)
24 . The structure of claim 1 , wherein pores in the first or second sheet of perforated two-dimensional material are at least 10-fold smaller than pores in the structural substrate.
25 . A method for forming a structure comprising:
disposing a first plurality of spacer elements between a first sheet of perforated two-dimensional material and at least one of a surface of a structural substrate and a surface of a second sheet of perforated two-dimensional material.
26 . The method of claim 25 , wherein said first plurality of spacer elements is disposed between said surface of said first sheet of perforated two-dimensional material and said surface of said second sheet of perforated two-dimensional material, said method further comprising:
providing a structural substrate on an alternate surface of the first or second sheet of perforated two-dimensional material.
27 . The method of claim 25 , wherein said first plurality of spacer elements is disposed between said surface of said first sheet of perforated two-dimensional material and said surface of said second sheet of perforated two-dimensional material, said method further comprising:
providing a second plurality of spacer elements on an alternate surface of the first or second sheet of perforated two-dimensional material; and
providing a structural substrate on said second plurality of spacer elements.
28 . The method of claim 25 , wherein
the spacer elements are applied to the structural substrate and the first or second sheet of perforated two-dimensional material is then applied to the spacer elements.
29 . The method of claim 25 , wherein the spacer elements are applied to the first or second sheet of two-dimensional material to form a composite material and the composite material is then applied to the structural substrate.
30 . (canceled)
31 . (canceled)
32 . A filtration membrane comprising a plurality of spacer elements disposed between a sheet of perforated two-dimensional material and a supporting substrate, the filtration membrane prepared by the method of claim 30 .
33 . A structure comprising:
a structural substrate having at least one relief feature at a surface of the structural substrate; and a first sheet of perforated two-dimensional material disposed upon the structural substrate such that said first sheet of perforated two-dimensional material substantially encloses the at least one relief feature.
34 . The structure of claim 33 further comprising a plurality of spacer elements disposed upon said first sheet of perforated two-dimensional material and a second sheet of perforated two-dimensional material disposed upon said plurality of spacer elements such that said spacer elements are between said first and second sheets of two-dimensional material.
35 . A method for forming a structure comprising:
providing a first sheet of a perforated two-dimensional material and a structural substrate;
forming at least one relief feature at a surface of the structural substrate; and
disposing the first sheet of perforated two-dimensional material upon the structural substrate.
36 . A filtration membrane to selectively separate components in a medium, comprising:
at least two sheets of perforated two-dimensional materials, each sheet having a plurality of selective pores and a plurality of non-selective pores,
wherein said plurality of selective pores are sized to allow a specified component in the medium to pass therethrough and said plurality of non-selective pores allow said specified component and components larger than said specified component to pass therethrough; and
wherein said plurality of selective pores and said plurality of non-selective pores are randomly distributed about each said sheet of perforated two-dimensional material; and
wherein said sheets of perforated two-dimensional materials are positioned adjacent one another with said plurality of selective pores of one of said sheets of perforated two-dimensional material randomly aligned with respect to said plurality of selective pores of said adjacent sheet of perforated two-dimensional material and said plurality of non-selective pores are randomly aligned with respect to said plurality of non-selective pores of said adjacent sheet of perforated two-dimensional material.
37 . The filtration membrane according to claim 36 , wherein said sheets of perforated two-dimensional material are positioned so as to provide flow paths only through aligned pores.
38 . The filtration membrane according to claim 36 , wherein said sheets of perforated two-dimensional material are positioned so as to provide a selective flow path in between said sheets.
39 . The filtration membrane according to claim 36 , wherein said sheets of perforate two-dimensional material are positioned so as to provide a non-selective flow path.
40 . The filtration membrane according to claim 36 further comprising a housing configured for reverse osmosis, nanofiltration, ultrafiltration, microfiltration, forward osmosis or pervaporative separation.