基于纳米分子筛敏感膜类神经毒气传感器

研究了ZSM5分子筛膜对神经类毒剂沙林的相似物甲基磷酸二甲脂的敏感特性,并结合高灵敏的石英谐振微天平(QCM)研制了甲基磷酸二甲脂气体传感器。测试甲基磷酸二甲脂气体的体积分数分别为10-6,5×10-6,20×10-6的气体。研究表明:基于ZSM5纳米分子筛膜的传感器的检测灵敏度高,对气体体积分数为10-6甲基磷酸二甲脂气体的检测灵敏度为60Hz/10-6,比半致死浓时积低;传感器的响应与脱附时间较快,对气体体积分数为10-6甲基磷酸二甲脂气体的响应与脱附时间均为100s;对同体积分数丙酮气体进行了频率响应测试,对传感器的选择性进行验证。还研究了ZSM5分子筛对甲基磷酸二甲脂气体的脱附再生条件,发现经过200℃脱附,分子筛的再生能力可以得到较好的恢复.

Nerve agent gas sensor based on nano-zeolite films

First using ZSM-5 zeolite films to detect the nerve agent similant Dimethylmethylphosphonate,which is regarded as the simulant for sarin.By combining the high sensitivity of QCM,the gas sensor is developed,and the gas volume fractions of 10~(-6),5×10~(-6),20×10~(-6) gases are detected.The result shows the sensitivity to 10~(-6) DMMP is 60Hz,which is lower than EC_(50) (The value of volume fraction times the time,which causes half of the people dead).The velocities of the absorption and desorption are very quick.The response time of absorption and desorption is 100s respectively.The selectivity is also tested with other gases such as acetone at the same volume fraction.The renewablecondition of the ZSM-5 films is also discussed.It is shown that at the desorption temperature of 200℃,the zeolite is thermally stable and shows reproducible response during DMMP gas detection.