Innovative Ethanol Sensors Utilizing Organic Material Patterned Surface Acoustic Wave Detection

In this paper, sensor based on surface acoustic waves for ethanol vapors detection, was fabricated and studied. For room temperature detection of the volatile compound, a novel carbyne nanofilm was deposited on the surface of a SAW transducer. The conventional electrodes were replaced by conductive polymeric coting of poly(3,4-ethylenedioxythiophene):poly (styrenesulfonate) (PEDOT:PSS) to minimize the microstructural and elemental difference between the electrode and gas sensitive material. The experimental results showed that the sensors had a good response to ethanol at room temperature. The maximum response of the sensors was at 600 ppm, where the time delay between the output and the input signals of the transducer was ~ 160 μs. The parasitic contact resistance and interface capacitance were found insufficient to affect the accuracy of the measurement, although their values are higher as compared to the sensors with metal electrodes.