Selectivity of Multi-wall Carbon Nanotube Network Sensoric Units to Ethanol Vapors Achieved by Carbon Nanotube Oxidation

Two kinds of multiwall carbon nanotubes (MWCNT) networks “Buckypaper” were made by the vacuum filtration method of MWCNT aqueous suspension. The first one was prepared from pure CNT and the second from its oxidized form. The CNT oxidation increase content of oxygen bonded to the surface of CNT. The sensitivity of MWCNT networks to organic solvent vapors (ethanol and heptane) has been investigated by resistance measurements. The solvents had different polarities given by Hansen solubility parameters and nearly the same volume fractions of saturated vapors at the condition of experiment. CNT oxidation significantly increases the sensitivity of CNT resistive sensoric unit to vapors of ethanol and decrease response to heptane vapors.