Absorption and desorption characteristic of zeolites in gas sensor system

Nanosized zeolites as a novel absorbent were investigated targeting for the nerve agent sarin stimulant gas DMMP. Quartz crystal microbalance (QCM) gas sensors modified with Silicalite-1 or Cu-ZSM-5 zeolites synthesized as micro-porous absorbents were fabricated and their gas response characteristics were examined to study the absorption capability of zeolites. The results indicated that Cu-ZSM-5 zeolite has stronger absorption capacity than Silicalite-1 due to the affinity between Cu²⁺ and DMMP. Within our experimental conditions, when desorption temperature is 523 K and desorption time is 30 minutes, the Cu-ZSM-5 zeolite not only have optimum desorption properties, also have good repeatability. Compared with Silicalite-1, Cu-ZSM-5 zeolite is a preferable absorption material for chemical warfare agent detection and it also can present a good selective and repeating ability.