Department of Health Sciences, University "Magna Græcia" of Catanzaro, Viale Europa, 88100 Catanzaro, Italy.
Sensors (Basel). 2020 Apr 10;20(7):2143. doi: 10.3390/s20072143.
The development of even more compact, inexpensive, and highly sensitive gas sensors is widespread, even though their performances are still limited and technological improvements are in continuous evolution. Zeolite is a class of material which has received particular attention in different applications due to its interesting adsorption/desorption capabilities. The behavior of a zeolite 4A modified capacitor has been investigated for the adsorption of nitrogen (N), nitric oxide (NO) and 1,1-Difluoroethane (CHF), which are of interest in the field of chemical, biological, radiological, and nuclear threats. Sample measurements were carried out in different environmental conditions, and the variation of the sensor electric capacitance was investigated. The dielectric properties were influenced by the type and concentration of gas species in the environment. Higher changes in capacitance were shown during the adsorption of dry air (+4.2%) and fluorinated gas (+7.3%), while lower dielectric variations were found upon exposure to N (-0.4%) and NO (-0.5%). The proposed approach pointed-out that a simple fabrication process may provide a convenient and affordable fabrication of reusable capacitive gas sensor.
尽管其性能仍然有限，技术改进也在不断发展，但更紧凑、更廉价、更高灵敏度的气体传感器的开发已经非常广泛。沸石是一类材料，由于其有趣的吸附/解吸能力，在不同的应用中受到了特别关注。已经研究了改性沸石 4A 电容器对氮气（N）、一氧化氮（NO）和 1,1-二氟乙烷（CHF）的吸附行为，这些气体在化学、生物、放射性和核威胁领域具有重要意义。在不同的环境条件下进行了样品测量，并研究了传感器电容的变化。介电性能受到环境中气体种类的类型和浓度的影响。在吸附干燥空气时（+4.2%）和氟代气体时（+7.3%）电容变化较大，而在暴露于 N（-0.4%）和 NO（-0.5%）时介电变化较小。该方法表明，简单的制造工艺可以为可重复使用的电容式气体传感器提供方便且经济实惠的制造方法。
