Capacitive Ammonia Sensor Based on Graphene Oxide/Polyaniline Nanocomposites

Abstract Toxic and irritant gases such as ammonia in enclosure space could destroy the respiratory system with an unobtrusive way. Monitoring high‐risk gases are imperative when humans expose in a vulnerable environment with unpredictable gases. Capacitive sensors are supposed to be an ideal choice applying to contactless gas sensing in enclosed space. This research develops an innovative model based on barrier capacitance theory for capacitive ammonia sensor. A capacitive ammonia sensor based on graphene oxide/polyaniline (GO/PANI) nanocomposites, which can be attached to enclosure space (pipes, storage tanks, etc.), is manufactured and exhibits high sensitivity (49.3 × 10 –5 ppm) and fast response (≈200 s) in the ammonia concentration range of 0–100 ppm. In particular, GO/PANI nanocomposites are modeled as barrier…