Aqueous carbon nanotube applicator liquids and methods for producing applicator liquids thereof

A method for making an applicator liquid, the method comprising:

• purifying a plurality of nanotubes to obtain purified nanotubes, wherein said step of purifying is accomplished by:
• contacting said plurality of nanotubes with an acid to create a nanotube-acid solution and dissolve metal impurities,
• separating the dissolved metal impurities from said nanotube-acid solution to obtain said purified nanotubes in said nanotube-acid solution, and
• contacting said plurality of nanotubes in the nanotube-acid solution with a base to return the pH level of the nanotube-acid solution to approximately neutral to obtain purified nanotubes;
• and
• contacting said purified nanotubes with water;
• wherein
• said applicator liquid contains said purified nanotubes distributed in said water without substantial precipitation for at least one hour after said contacting;
• said applicator liquid is free of polymers and surfactants;
• and
• said applicator liquid has a group I metal impurities content of less than 100 ppb.