All-aerosol-jet-printed Fe3+ modified bilayers polyaniline flexible room temperature sensor with enhanced ammonia sensing properties

The rapid advancement of human-machine interaction (HMI), the Internet of Things (IoTs), and artificial intelligence (AI) has imposed greater demands on the ambient temperature wearable performance of sensors. In this study, the Fe 3+ modified bilayers polyaniline (PANI) flexible room temperature ammonia sensor is prepared by all-aerosol-jet-printed. The increased protonation degree of the PANI film produced by this method was elucidated through analysis of aerosol microdroplet evaporation behavior, while the improved ammonia sensing performance of the PANI/Fe 3+ dendritic structure was explained using soft and hard acid-base theory. Gas sensing tests demonstrated that the PANI/Fe 3+ sensor exhibited high sensitivity to ammonia (776 % at 55 ppm), a wide detection range (547 ppb-547 ppm), as well as excellent selectivity, flexibility, and cyclic stability. These results underscore its potential for application in ambient temperature wearable fields.