Capacitance and conductance of single-walled carbon nanotubes in the presence of chemical vapors

Simultaneous conductance and capacitance measurements on a single-walled carbon nanotube (SWNT) network are used to extract an intrinsic property of molecular adsorbates. Adsorbates from dilute chemical vapors produce a rapid response in both the capacitance and the conductance of the SWNT network. These responses are caused by a combination of two distinct physiochemical properties of the adsorbates: charge transfer and polarizability. We find that the ratio of the conductance response to the capacitance response is a concentration-independent intrinsic property of a chemical vapor that can assist in its identification.