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论文类型：期刊论文

发表时间：2010-05-06

发表刊物：JOURNAL OF PHYSICAL CHEMISTRY C

收录刊物：SCIE、EI、Scopus

卷号：114

期号：17

页面范围：7986-7994

ISSN号：1932-7447

摘要：Dimethylmethylphosphonate (DMMP) is a simulant for the highly toxic organophosphate nerve agent Sarin (GB). The influence of DMMP on the ionic conductivity of zeolite Y is investigated by impedance spectroscopy. In the presence of 20-100 ppm of DMMP, the ionic conductivity of the sodium exchanged form of the zeolite showed an increase. The interaction between DMMP and the zeolite was elucidated by examining different cation-exchanged zeolites as well as external surface modification with ceria to deactivate acidic groups. A mechanism involving the binding of the sodium cation with the phosphonate group of DMMP that results in facilitated inter cage motion of the cation is proposed. The change in impedance measured at a single frequency of 3000 Hz allows for the use of Na(+)-exchanged zeolite Y as a sensor for detecting ppm level of DMMP. Sensing data were obtained over a temperature range of 300-350 degrees C, with best results at 320 degrees C. This device exhibited minimal response to CO, NH(3), methane, and propane, possible interferents in the ambient air.