Method for assembling nano objects
AssigneeThe University of North Carolina at Chapel Hill
InventorsOtto Z. Zhou, Hideo Shimoda, Soojin Oh
Life of this patent
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Abstract
A method for the self assembly of a macroscopic structure with a pre-formed nano object is provided. The method includes processing a nano object to a desired aspect ratio and chemical functionality and mixing the processed nano object with a solvent to form a suspension. Upon formation of the suspension, a substrate is inserted into the suspension. By evaporation of the solvent, changing the pH value of the suspension, or changing the temperature of the suspension, the nano objects within the suspension deposit onto the substrate in an orientational order. In addition, a seed crystal may be used in place of the substrate thereby forming single-crystals and free-standing membranes of the nano-objects.
Claims49
A method for assembling nano objects onto a macroscopic structure, the method comprising:
- (a) processing nano objects to a desired aspect ratio and chemical functionality;
- (b) admixing the processed nano objects with a solvent to form a suspension, the suspension having a concentration, a temperature and a pH level;
- (c) submersing a substrate into the suspension;
- and
- (d) changing the concentration to control deposition of the nano objects onto the substrate, thereby assembling the macroscopic structure onto the substrate.
A method for assembling pre-formed nano objects into a macroscopic structure, the method comprising:
- (a) processing the nano objects, wherein the processing of the nano object comprises:
- (i) synthesizing the pre-formed nano objects, where the pre-formed nano objects are single wall carbon nanotube (SWNT) bundles;
- (ii) purifying the SWNT bundles by reflux in a hydrogen peroxide solution and filtering the SWNT bundles;
- and
- (iii) cutting the purified SWNT bundles by reacting the SWNTs with HNO3 and/or H2SO4, and with ultra-sonication;
- (b) forming a suspension by admixture of the nano objects with a solution;
- (c) inserting a substrate into the suspension;
- and
- (d) gradually removing the substrate from the suspension during which the nano objects from the suspension deposit on the surface of the substrate.
A method for assembling pre-formed nano objects into a macroscopic structure, the method comprising:
- (a) processing the nano objects;
- (b) forming a suspension by admixture of the nano objects with a solution;
- (c) inserting a substrate into the suspension;
- and
- (d) gradually removing the substrate from the suspension during which the nano objects from the suspension deposit on the surface of the substrate, wherein the nano objects form on an air/liquid/substrate triple line of the substrate.
A method for assembling nano objects into a free-standing macroscopic structure, the method comprising:
- (a) processing the nano objects such that the nano objects disperse or dissolve in a solvent;
- (b) admixing the processed nano objects with the solvent to form a stable suspension or a solution in a container that does not attract the processed nano objects;
- (c) submersing a seed-crystal into the suspension;
- and
- (d) changing a concentration of the suspension to bring the suspension into super-saturation such that the processed nano objects assemble into a free-standing macroscopic structure.
A method for fabricating electron field emission cathodes by self-assembly of pre-formed nano objects, the method comprising:
- (a) processing the nano objects such that the nano objects disperse or dissolve in a solvent;
- (b) admixing the processed nano objects with the solvent to form a suspension;
- (c) submersing a substrate into the suspension;
- and
- (d) changing a concentration of the suspension to assemble the processed nano objects on certain regions of the substrate surface thereby fabricating the electron field emission cathode,
- wherein the substrate comprises a region A and a region B where the region A attracts the processed nano objects and the region B does not attract the processed nano objects where the nano objects deposit on the region A upon changing the concentration of the suspension.
A method for assembling nano objects onto a macroscopic structure, the method comprising:
- (a) processing nano objects to a desired aspect ratio and chemical functionality;
- (b) admixing the processed nano objects with a solvent to form a suspension, the suspension having a concentration, a temperature and a pH level;
- and
- (c) coating the suspension onto a substrate thereby assembling the macroscopic structure onto the substrate.
Dependencies are inferred from the claim text.