Selectivity enhancement of metal oxide gas sensors using a micromachined gas chromatographic column
Selectivity enhancement of metal oxide gas sensors using a micromachined gas chromatographic column
复制标题
DOI：
10.1016/j.snb.2004.06.036
复制
发表时间：
2005-03-28
影响因子：
8.4
通讯作者：
Cardinali, C
中科院分区：
文献类型：
--
作者：
Zampolli, S;Elmi, I;Cardinali, C
室内空气质量监测应用需要高灵敏度和高选择性，这是固态气体传感器难以达到的。虽然对于一些气体种类，例如CO和NO2，使用优化的操作条件允许达到必要的选择性，但是单个挥发性有机化合物（VOC）之间的区分通常不可能使用独立的气体传感器阵列。本文提出了一种基于类气相色谱（GC）方法的高选择性混合微系统。该系统以固态气体传感器为检测器，采用硅微机械填充气相色谱柱、零级空气装置、微型泵和微型阀。利用该原型，可以可靠地检测和测量合成或真实的室内空气中洗脱的苯、甲苯和间二甲苯，浓度低至5 ppb。色谱单元与固态气体传感器一起使用，两者都集成在硅中，允许开发具有优异选择性和再现性的低成本手持便携式设备。这些性能的潜在应用包括安全控制、空气质量监测以及食品质量控制。(c)2004 Elsevier B.V.保留所有权利。
Indoor air quality monitoring applications require both high sensitivity and selectivity, which are difficult to reach with solid state gas sensors. While for some gas species like, e.g. CO and NO2, the use of optimized operating conditions allows to reach the necessary selectivity, the discrimination between single volatile organic compounds (VOC) is generally not possible with stand-alone arrays of gas sensors. This limitation represents a major drawback, since not all indoor VOC are equally harmful for the health of the human beings living in the polluted environment.For this reason, a highly selective hybrid microsystem based on a gas chromatographic-like (GC) approach is proposed. In this miniaturized gas chromatographic system a solid state gas sensor is used as detector, together with a Silicon micromachined packed GC column, a zero grade air unit, a commercial minipump and a minivalve. With this prototype, Benzene, Toluene and m-Xylene eluted in synthetic or real indoor air were reliably detected and measured at concentrations as low as 5 ppb. The use of chromatographic units together with solid state gas sensors both integrated in silicon allows to develop low-cost, handheld portable devices having exceptional selectivity and reproducibility. Possible applications which could benefit of these performances include security control, air quality monitoring as well as food quality control. (c) 2004 Elsevier B.V. All rights reserved.