Effect of Surface Modification of CNTs on Response Behavior of Conductive Polymer Composite Vapor Sensors

A novel vapour sensor was fabricated by multi-walled carbon nanotube porous composite. In this study poly (methyl methacrylate) (PMMA) was used as matrix. Porous sensing films were obtained by dry-cast non-solvent induced phase separation (NIPS) method. The effect of surface modification of CNT by nitric acid on response of porous sensors was evaluated. The resistance responsiveness of sensors against various organic vapours was investigated. It was observed that functionalized CNT/PMMA composite sensors showed a higher response in comparison with composite with pristine nanotube. Their response was approximately ten times greater than the response of similar sensors without modification of CNT. It is explained on the basis of polar interaction of vapours on the surface of CNT and better dispersion of nanotubes in polymer matrix.

Keywords:

Conductive Composite , Phase Separation , Carbon Nanotube , Vapours Sensor , Surface Modification