Response model for thermally modulated tin oxide-based microhotplate gas sensors
Response model for thermally modulated tin oxide-based microhotplate gas sensors
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DOI：
10.1016/s0925-4005(03)00420-9
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发表时间：
2003-10-15
影响因子：
8.4
通讯作者：
Correig, X
中科院分区：
文献类型：
--
作者：
Ionescu, R;Llobet, E;Correig, X
为了深入了解温度调制金属氧化物气体传感器的电导响应，我们引入了传感操作中涉及的物理化学过程的模型。为此，我们考虑了在还原性和氧化性物质存在的情况下传感器表面发生的相互作用。然后，我们根据空气中CO和NO2 ppm水平存在的实验响应验证了模型。正弦电压驱动电阻铂加热器并调制微机械氧化锡气体传感器的温度；分析了由此产生的电导变化。在理论和实验响应之间取得了很好的一致性。所建立的模型用于计算温度调制传感器在不同浓度CO和NO2存在下的电导响应。利用离散小波变换提取仿真响应的瞬态特征，并利用主成分分析进行分类。得到了CO和NO2的线性分离，这与我们之前的实验结果很好地吻合。(C) 2003 Elsevier B.V.版权所有
To gain some insight into the conductance response of temperature-modulated metal oxide gas sensors, we introduce a model for the physicochemical processes involved in the sensing operation. For this, we consider the interactions that take place at the sensor surface in the presence of reducing and oxidising species. Then we validate the model against experimental responses in the presence of ppm levels of CO and NO2 in air. A sinusoidal voltage drives a resistive platinum heater and modulates the temperature of a micromachined tin oxide gas sensor; the resulting variation in conductance is analysed. Excellent agreement between theoretical and experimental responses is achieved. The model developed was used to compute the conductance response of a temperature-modulated sensor in the presence of different concentrations of CO and NO2. Features from the simulated response transients were extracted using the discrete wavelet transform and classified using a principal component analysis. A linear separation between CO and NO2 was obtained, which is in good agreement with our previous experimental results. (C) 2003 Elsevier B.V. All rights reserved.