Nanotube solution treated with molecular additive, nanotube film having enhanced adhesion property, and methods for forming the nanotube solution and the nanotube film
The present disclosure provides a nanotube solution being treated with a molecular additive, a nanotube film having enhanced adhesion property due to the treatment of the molecular additive, and methods for forming the nanotube solution and the nanotube film. The nanotube solution includes a liquid medium, nanotubes in the liquid medium, and a molecular additive in the liquid medium, wherein the molecular additive includes molecules that provide source elements for forming a group IV oxide within the nanotube solution. The molecular additive can introduce silicon (Si) and/or germanium (Ge) in the liquid medium, such that nominal silicon and/or germanium concentrations of the nanotube solution ranges from about 5 ppm to about 60 ppm.
1. A method for forming a nanotube application solution, comprising:
dispersing functionalized nanotubes in a liquid medium to form an initial nanotube solution;
dispersing molecular silica into said initial nanotube solution; and
adding a selected concentration of molecular additive to said initial nanotube solution to obtain a nanotube application solution, wherein said selected molecular additive concentration promotes the formation of molecular silica while inhibiting the formation of colloidal silica particles within said nanotube application solution;
wherein said molecular additive is a compound containing at least one group IV component;
wherein said molecular silica has a concentration of less than 60 parts per million (ppm) of silicon within said nanotube application solution; and
wherein said nanotube application solution is free of surfactants.
2. The method of claim 1 wherein said selected concentration of molecular additive is below the critical concentration where particulates begin to form.
3. The method of claim 2 wherein said nanotube application solution is free of molecular additive particulates greater than 10 nanometers.
4. The method of claim 2 wherein said nanotube application solution is free of molecular additive particulates greater than 5 nanometers.
5. The method of claim 2 wherein said nanotube application solution is free of molecular additive particulates greater than 3 nanometers.
6. The method of claim 1 wherein said molecular additive is a silicon-based molecular additive.
7. The method of claim 6 wherein said silicon-based molecular additive is molecular silica.
8. The method of claim 6 wherein said silicon-based molecular additive comprises a silicon oxide compound.
9. The method of claim 1 wherein said molecular additive is a germanium compound.
10. The method of claim 9 wherein said germanium compound contains at least one of germanium isopropoxide, bis(2-carboxyethylgermanium) sesquioxide, and polygermsesquioxanes.
11. The method of claim 1 wherein said molecular additive is one of tin oxide and lead oxide.
12. The method of claim 1 wherein said at least one group IV based component is selected from the list consisting of Si, Ge, Sn, and Pb.
13. The method of claim 1 wherein said molecular additive comprises a water soluble silsesquioxane cage molecule.
14. The method of claim 1 wherein said molecular additive is one of Octakis(tetramethylammonium)-T8-Silsesquioxane and PSS hydrate-Octakis(tetramethylammonium).
15. The method of claim 1 wherein said nanotube application solution is free of polymers.
16. The method of claim 1 wherein said step of adding a selected concentration comprises adding a predetermined amount of molecular additive to said initial nanotube solution.
17. The method of claim 1 wherein said initial nanotube solution is purified prior to said step of adding a selected concentration of molecular additive.
18. The method of claim 17 wherein said purified nanotube solution has trace metal concentrations below 25 parts per billion (ppb).
19. The method of claim 18 said purified nanotube solution having trace metal concentrations below 1 parts per billion (ppb).
20. The method of claim 18 wherein said trace metals include at least one of Na, Mg, Al, K, Ca, Ti, Cr, Mn, Fe, Co, Ni, Cu, Zn, and all ionic species thereof.
21. The method of claim 1 wherein said liquid medium is water.
22. The method of claim 1 wherein said liquid medium is an organic solvent.
23. The method of claim 1 wherein said selected concentration level is below the saturation concentration of said molecular additive.