Compositions comprising a plurality of discrete nanostructures and related articles and methods
Embodiments described herein generally relate to compositions including discrete nanostructures (e.g., nanostructures including a functionalized graphene layer and a core species bound to the functionalized graphene layer), and related articles and methods. A composition may have a coefficient of friction of less than or equal to 0.02. Discrete nanostructures may have a substantially non-planar configuration. A core species may reversibly covalently bind a first portion of a functionalized graphene layer to a second portion of the functionalized graphene layer. Articles, e.g., articles including a plurality of discrete nanostructures and a means for depositing the plurality of discrete nanostructures on a surface, are also provided. Methods (e.g., methods of forming a layer) are also provided, including depositing a composition onto a substrate surface and/or applying a mechanical force to the composition, e.g., such that the composition exhibits a coefficient of friction of less than or equal to 0.02.
1. A composition, comprising:
a plurality of discrete nanostructures, each nanostructure comprising a functionalized graphene layer and a core species bound to the functionalized graphene layer;
wherein the composition has a coefficient of friction of less than or equal to 0.02, as determined using a linear tribometer equipped with a diamond-like carbon coated stainless steel ball, and
wherein the functionalized graphene layer has an average surface area of greater than or equal to 0.01 microns 2 and less than or equal to 40 microns 2 .
2. A composition, comprising:
a plurality of discrete nanostructures, each nanostructure comprising a functionalized graphene layer and a core species bound to the functionalized graphene layer;
wherein the plurality of discrete nanostructures have a substantially non-planar configuration, and
wherein the functionalized graphene layer has an average surface area of greater than or equal to 0.01 microns 2 and less than or equal to 40 microns 2 .
3. A composition, comprising:
a plurality of discrete nanostructures, each nanostructure comprising a functionalized graphene layer and a core species bound to the functionalized graphene layer;
wherein the core species reversibly covalently binds a first portion of the functionalized graphene layer to a second portion of the functionalized graphene layer, and
wherein the functionalized graphene layer has an average surface area of greater than or equal to 0.01 microns 2 and less than or equal to 40 microns 2 .
4. A composition as in claim 1 , wherein the plurality of discrete nanostructures have a crumpled configuration.
5. A composition as in claim 1 , wherein at least some of the plurality of discrete nanostructures comprise a chemically reversible linkage.
6. A composition as in claim 1 , wherein at least some of the plurality of discrete nanostructures has a chemical bond for mechanical energy dissipation.
7. A composition as in claim 1 , wherein at least some of the plurality of discrete nanostructures form and/or are formed from a molecular bearing.
8. A composition as in claim 1 , wherein the composition has a fluid-like property.
9. A composition as in claim 1 , wherein the composition is configured, upon application of a mechanical force to the composition, to maintain a coefficient of friction of less than or equal to 0.02.
10. A composition as in claim 1 , wherein the plurality of discrete nanostructures is configured such that, under the application of mechanical force, at least a portion of the plurality of discrete nanostructures obtain a substantially non-planar configuration.
11. A composition as in claim 1 , wherein the core species is configured to maintain the plurality of discrete nanostructures in a substantially non-planar configuration.
12. A composition as in claim 1 , wherein the composition exhibits superlubricity.
13. A composition as in claim 1 , wherein the composition is configured for use as a tribo-layer.
14. A composition as in claim 1 , wherein the composition is bound to a surface comprising a metal, diamond-like carbon, an alloy, a mineral, a glass, a ceramic, a diamond, a form of carbon, and/or a plastic.
15. A composition as in claim 1 , wherein the functionalized graphene layers are functionalized with 3,5-dinitrophenyl groups.
16. A composition as in claim 1 , wherein the functionalized graphene layers comprise graphene oxide.
17. A composition as in claim 1 , wherein the core species is configured to bind to a metal surface.
18. A composition as in claim 1 , wherein the core species comprises an amine.
19. A composition as in claim 1 , wherein the core species comprises a triptycene.
20. A composition as in claim 1 , wherein the core species comprises an alcohol.
21. A composition as in claim 1 , wherein the core species comprises a phosphorus compound.
22. A composition as in claim 1 , wherein the functionalized graphene layer is at least partially wrapped around the core species.
23. A composition as in claim 1 , wherein the composition has a coefficient of friction of less than or equal to 0.015.