Effect of water on the electrical properties of carbon nanotubes.

In this work we present the electrical characterization of carbon nanotubes synthesized by a thermal chemical deposition method, using carbon disulfide as the precursor of carbon and iron as the catalyst. We found a broad maximum in the electrical resistance as a function of temperature between 275-300 K and a hysteretic behavior when the measurements were made in a humid environment. We propose that the water molecules act as traps for charge carriers, and the overall behavior of the observed phenomenon is discussed in terms of the confinement of water inside the carbon nanotubes.