Gas sensing improvement of carbon nanotubes by NH4OH–flash treatment: a nondestructive purification technique

Abstract
Surface carbonaceous impurities are removed from carbon nanotubes by NH4OH–flash treatment and microscope analyses reveal that the carbon walls retain integrity and the tube resistance is reduced by 17% of the initial value. Clean tubes exhibit a significant improvement on gas sensitivity and O2 adsorption–desorption becomes reversible.