Excess noise in a drop-coated poly(vinyl butyral)\carbon black nanocomposite gas sensitive resistor

Presented are the results of excess noise measurements on poly(vinyl butyral)\carbon black nanocomposite gas sensitive resistors. The devices were prepared by a drop-coating technique in which a microlitre syringe was used to deposit the materials onto Cu thin-film parallel electrodes. Noise power spectra of the devices under bias currents ranging from 80 to 150 μA were obtained. The detection limits were found to be 6.3 ppm, 5.2 ppm and 68 ppb for methanol, propanol and hexanol vapour, respectively. The noise index was also evaluated for the devices, with a value of approximately 29 dB being measured.