Room-temperature dosimeter-type gas sensors with periodic reset

摘要: Abstract NO 2 sensing tests have been performed on room-temperature-operated SnO gas sensors. Due to elongated response and recovery time constants these sensors exhibited a dosimeter rather than conventional concentration-dependent response. In order enable continuous monitoring such need be subjected periodically repeated sense & reset operations. Reset procedures which proved effective in restoring baseline conductance again are low-temperature annealing (T ∼ 120 °C), ultraviolet (UV) light exposure, exposure humidified synthetic air (T ∼ 300 K, r.h. ∼ 80%). Unlike high-temperature sensors, room-temperature operated exhibit very little intrinsic sensor drift. Severe levels of drift, however, can arise from contamination-induced effects the periphery. It is demonstrated that drifts effectively compensated by exploiting knowledge about timing