Hydrogen sulfide
Sensing targets can be expanded through adding materials to the polyaniline nanofibers. One study proposes polyaniline nanofiber composites with metal salts for the detection of hydrogen sulfide. Hydrogen sulfide is a weak acid that is dangerous at low ppm, but polyaniline nanofibers can only give a robust response to strong acids. Metal salts can react with hydrogen sulfate to form a metal sulfide precipitate and a strong acid. By combining metal salts and polyaniline nanofibers, detection of hydrogen sulfide can be performed.