QCM Gas Sensor Based on Modified Silicate-1 Zeolite for the Nerve Agent Simulant DMMP Detection

A new quartz crystal microbalance(QCM)gas sensor based on the silicate-1 zeolite film is introduced.The sensitive characteristics to the nerveagent sarin stimulant dimethylmethylphosphonate(DMMP)of the gas sensor have been systematically studied.Different concentration DMMP are detected by the sensor.As the concentration of DMMP increases,the respone time increases,and the absorbed capability of QCMsensor increases.The delta frequency of QCMis 50 Hz to 50×10-6 DMMP.In order to test the selectivity of the gas sensor,water vapor,300×10-6 CO2 and 500×10-6 NH3 are used as interfering gases.The delta frequencies of QCMto these gases are 178 Hz,28 Hz and 15 Hz.In 60 seconds the gas sensor obtained 85% desorption ratio by alternating field with 99.999% N2 blow-washing in this experiment.