Room Temperature Operated PEDOT: PSS Based Flexible and Disposable NO2 Gas Sensor

This work presents a flexible and disposable nitrogen dioxide (NO2) gas sensor based on Poly(3,4ethylenedioxythiophene): poly(styrenesulfonate) (PEDOT:PSS), operating at room temperature (RT). The gas sensing layer, composed of PEDOT:PSS, is deposited on interdigitated electrodes (IDEs) made from graphene-carbon ink, which are screen printed onto a paper substrate using the drop casting method. The Fourier-transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) analyses are carried out to understand the successful deposition and surface morphology analysis of the sensing layer. The NO2 sensing properties are explored in the range 0.5-50 ppm at RT (27 degrees C +/- 2 degrees C). The sensor displays significant % response viz., 0.79%-12.97% in the measured range 0.5-50 ppm. Other important sensing characteristics, such as response and recovery times (210 s / 60 s at 0.5 ppm), repeatability, and reproducibility along with sensing mechanism are also presented. The findings of this letter suggest that the developed sensor holds promise for various application areas.