Effects of organic solvent vapours on resistance and noise of a drop-coated poly(vinyl butyral)\carbon black nanocomposite

Presented are the results of investigations of the effects of organic solvent vapours and excess noise measurements on drop-coated poly(vinyl butyral)\carbon black nanocomposite gas sensitive resistors. The devices were shown to exhibit significant resistance changes upon exposure to methanol, propanol and particularly hexanol vapours in the concentration range 1000 to 5000 ppm. The effects of the organic solvent vapours on the noise power spectra of the PVB\CB sensors were also investigated, but results were found to yield no information surplus to that of the DC sensor signal. The large values of 1/f noise observed were attributed to inhomogeneity and discontinuity of the deposited sensing layer. The discontinuity of the drop-coated layer was subsequently confirmed by SEM micrographs of the samples.