Improving Selectivity of Ce_0.1Mn_0.9Ox/Pt–SnO₂ Laminated MOS Sensor for Soman Under Temperature Dynamic Modulation

Metal oxide semiconductor sensors have a great potential for application in the field of chemical warfare agent sensors by virtue of their performance advantages;，however，the lack of selectivity to chemical warfare agents is the main technical bottleneck restricting the development of such sensors. The sensing materials of traditional metal oxide semiconductor sensors usually adopted a single layer of gas sensitive film, on the basis of which this paper constructed a catalytic film/gas sensitive film laminated structure of sensing materials and adopted the method of temperature dynamic modulation to obtain the sensor's resistance response to soman accordingly. The experimental results showed that the Ce<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0.1</sub>Mn<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0.9</sub>Ox/Pt-SnO<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> laminated sensor exhibited obvious peak signals under certain temperature dynamic modulation conditions, with a peak height of 0.11. However, no peak signals were detected in the resistance of 12 interfering gases, such as methane, and the height of the peaks were lower than 0. The research confirmed that the catalytic film/gas sensitive film laminated metal oxide semiconductor sensor could achieve high selectivity for soman under certain temperature dynamic modulation conditions, and at the same time, it also possessed good response time, stability, and anti-interference ability.