1991 Volume 40 Issue 4 Pages T77-T81
An Au-poly(ethylene oxide)4.5AgCF3SO3-Ag galvanic gas detector, consisting of a disc (13mm in diameter×1.1mm thick) has been developed by utilizing a polymeric electrolyte film (30μm thick). The polymeric films were made by mixing acetonitrile solution with both AgCF3SO3 and polyethylene oxide. The mixture was cast on the disc and the solvent was permitted to evaporate. The working electrode (25nm thick) was made by coating it with vaporized gold. The maximum response appeared within 3 s after the sample (2.6ml) was injected into the nitrogen carrier stream. The flow rate was 40ml min-1. The longest time to return to the base line was 3 min. The maximum current flowing in the external circuit increased linearly relating to the concentration of NO2 in the range 0.28ppm at ambient temperature. Twenty samples could be analyzed per hour. The relative standard deviation of the response for 1.0ppm of NO2 using 2.6ml sample was about 3%. After 200 samples (1ppm of NO2-2.6ml) had been analyzed, the response decreased by about 15% of its original value.
