TiO2 nanofibrous chemoresistors coated with PEDOT and PANi blends for high performance gas sensors

Hybrid sensors consisting of nanofibrous scaffolds of TiO2 coated with thin films of self-assembled conductive polymer (CPs) blends have been recently tested in their capability of detecting traces of some gaseous markers of metabolic diseases, treated meat or spoiled food and explosives, and the resulting sensors have been compared in their sensing properties. In the present study, fibresimilar chemoresistors, based on the integration of a nanosized TiO2 and different blends of organic polymers (PEDOT:PSS and PANi:PS) were designed and set up. The resulting sensors showed an overall enhancement of sensing performances (sensitivity, selectivity, rapid responses, etc.) and greater lifetimes, and decrease in drawbacks of each polymer. Sensing characteristics towards NO2 and NH3 were tested at both the equilibrium and within a shorter time upon the rapid sensor responses, and results were discussed. Since the reaction between sensors and analytes was assumed to occur at the interface between CPs and TiO2, the resulting film structures were also investigated through scanning and transmission electron microscopy.