Electrically switchable carbon nanotubes hydrophobic surfaces

The influence of the electric field on the IR spectrum of water adsorbed on self assembled p-type carbon nanotubes (CNTs) has been investigated. The IR transmittance show that in the absence of an externally applied electric field a negligible amount of water molecules adsorbs on the tubes. In sharp contrast, under the electric field, the water stabilize on the CNTs. The physisorption of H2O at room temperature does cause activation of carriers, as monitored by the loss of transparency in the IR. When the electrical field is removed the original transparency is restored. A possible interaction of the H2O dipole with CNTs is proposed.