Impact of solvent on ammonia detection performance of polyaniline-based sensors
Résumé
Ammonia constitutes a polluting gas in the atmosphere. Chemiresistive sensors based on the polyaniline (PAni) can be used to monitor it. In this technology, the doped PAni is dispersed in a solvent like m-cresol, n-methyl-2-pyrrolidone or dichloroacetic acid, as reported in the literature. However, these solvents cause environmental and toxicity issues. This study aims to identify a safer solvent for PAni formulation displaying efficient gas sensing performances. Several alternative organic solvents were selected and tested in the formulation of PAni doped with camphorsulfonic acid. PAni-films morphology was characterized using SEM. Sensing performances of those materials formulated with various solvents have been evaluated at different ammonia concentrations. The role of the active layer morphology on the sensing performance has been specially discussed.